AI Trajectory

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Seq	Timestamp	Type	Name	Duration
0/0	2026/09/20 21:56	flow	patch-triage	2m Args: null Results: { "EnableConfigs": [ "NETFILTER", "NF_CONNTRACK", "NF_TABLES", "NFT_CT", "NF_CONNTRACK_TIMEOUT", "OPENVSWITCH", "NET_ACT_CT" ], "FocusSymbols": [ "nf_ct_get_careful", "nf_conntrack_in", "nf_ct_call_helper", "nf_confirm_get_protoff", "nf_confirm", "nf_ct_helper", "nft_ct_get_safe", "nft_ct_helper_obj_eval", "nft_ct_timeout_obj_eval", "nft_ct_expect_helper_alloc" ], "KMSANReasoning": "The patch series addresses protocol revalidation in netfilter conntrack (adding `nf_ct_get_careful`, `nf_confirm_get_protoff`, and safe helpers) to prevent mismatched conntrack state when packets are mangled earlier in the network pipeline (e.g., via TC pedit).\n\nNone of the changes introduce uninitialized memory risks:\n1. No kernel structures or data are copied to userspace (no `copy_to_user`, netlink attributes, socket options, or ioctl responses modified).\n2. All local stack variables and tuples (`tuple`, `inverse`, `pnum`, `protonum`, `ctinfo`) are either explicitly initialized, zeroed with `memset` (e.g. within `nf_ct_get_tuple` and `nf_ct_invert_tuple`), or populated by their respective accessor functions before being read in conditional logic.\n3. Heap allocations modified (`kzalloc_obj` in `nft_ct_expect_helper_alloc`) already use zero-initialization, and the added field `l4proto` is explicitly set.\n4. The added bounds and header checks (e.g., verifying `protoff` and TCP header `doff` bounds in `nf_confirm_get_protoff`) prevent out-of-bounds reads and protocol misinterpretations, which are handled by KASAN rather than KMSAN.\n\nTherefore, standard KASAN fuzzing is fully sufficient and a dedicated KMSAN session is not justified.", "NeedsKMSAN": false, "Reasoning": "The patch series modifies core netfilter and conntrack packet processing logic. It introduces protocol revalidation in nf_ct_get_careful() to detect mangled packets and drop invalid conntrack references, refactors conntrack helper invocation via nf_ct_call_helper() with strict header/proto verification (nf_confirm_get_protoff()), and adds nft_ct_get_safe() to enforce L4 protocol consistency before evaluating nftables conntrack timeout and helper objects. These reachable networking paths process untrusted packets and benefit from targeted fuzzing.", "WorthFuzzing": true }
1/1	2026/09/20 21:56	action	read-patch-diff	0m Args: null Results: { "PatchDiff": "commit 333bae72c14536cb20a3870b168802381646e895\nAuthor: syz-cluster \u003ctriage@syzkaller.com\u003e\nDate: Sun Sep 20 21:56:54 2026 +0000\n\n syz-cluster: applied patch under review\n\ndiff --git a/include/net/netfilter/nf_conntrack_helper.h b/include/net/netfilter/nf_conntrack_helper.h\nindex 335b8c43694f8..4b5ee758cff36 100644\n--- a/include/net/netfilter/nf_conntrack_helper.h\n+++ b/include/net/netfilter/nf_conntrack_helper.h\n@@ -124,6 +124,8 @@ int __nf_ct_try_assign_helper(struct nf_conn ct, struct nf_conn tmpl,\n \n int nf_ct_helper(struct sk_buff skb, struct nf_conn ct,\n \t\t enum ip_conntrack_info ctinfo, u16 proto);\n+int nf_ct_call_helper(struct sk_buff skb, struct nf_conn ct,\n+\t\t enum ip_conntrack_info ctinfo);\n int nf_ct_add_helper(struct nf_conn ct, const char name, u8 family,\n \t\t u8 proto, bool nat, struct nf_conntrack_helper *hp);\n \ndiff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c\nindex d0d9e5ea84a09..cd543c7b66a34 100644\n--- a/net/netfilter/nf_conntrack_core.c\n+++ b/net/netfilter/nf_conntrack_core.c\n@@ -2000,6 +2000,100 @@ static int nf_conntrack_handle_packet(struct nf_conn ct,\n \treturn generic_packet(ct, skb, ctinfo);\n }\n \n+\n+static bool nf_ct_check_icmp_inner(const struct sk_buff skb,\n+\t\t\t\t const struct nf_hook_state state,\n+\t\t\t\t unsigned int dataoff,\n+\t\t\t\t struct nf_conn ct,\n+\t\t\t\t enum ip_conntrack_dir dir)\n+{\n+\tstatic const unsigned int icmp_hdrsz = 8;\n+\tstruct nf_conntrack_tuple tuple;\n+\n+\tif (!nf_ct_get_tuplepr(skb, dataoff + icmp_hdrsz, state-\u003epf,\n+\t\t\t state-\u003enet, \u0026tuple))\n+\t\treturn false;\n+\n+\treturn nf_ct_tuple_equal(\u0026tuple, nf_ct_tuple(ct, !dir));\n+}\n+\n+/\n+ nf_ct_get_careful - Get connection tracking entry with protocol revalidation\n+ \n+ @skb: Socket buffer whose conntrack entry is to be retrieved\n+ * @state: Netfilter hook state\n+ * @dataoff: Offset to the layer-4 header within @skb\n+ * @protonum: protocol number (e.g., IPPROTO_TCP)\n+ * @ctinfo: Pointer to store ip_conntrack_info\n+ \n+ This function retrieves the connection tracking entry associated with @skb.\n+ * Performs revalidation of packet header, unlike nf_ct_get().\n+ \n+ If earlier in-kernel mangling (e.g., via TC pedit or clsact) altered packet\n+ * contents (e.g. changing TCP to UDP), this function will drop the conntrack\n+ * reference and returns NULL. skbs coming in via NF_INET_LOCAL_OUT are\n+ * trusted and never revalidated.\n+ \n+ Returns:\n+ * %NULL - No valid conntrack entry exists or revalidation failed.\n+ * Pointer to \u0026struct nf_conn associated with skb, may be a template.\n+ /\n+static struct nf_conn \n+nf_ct_get_careful(struct sk_buff skb,\n+\t\t const struct nf_hook_state state,\n+\t\t unsigned int dataoff, u8 protonum,\n+\t\t enum ip_conntrack_info ctinfo)\n+{\n+\tstruct nf_conn tmpl = nf_ct_get(skb, ctinfo);\n+\tstruct nf_conntrack_tuple inverse;\n+\tstruct nf_conntrack_tuple tuple;\n+\tenum ip_conntrack_dir dir;\n+\n+\t/* LOCAL_OUT is trusted: in case stack sends ICMP error, skb gets\n+\t * the conntrack assigned via nf_ct_attach().\n+\t \n+\t Such conntrack may not even be in hashtable yet, so\n+\t * nf_conntrack_handle_icmp() cannot find a connection matching\n+\t * the inner header.\n+\t /\n+\tif (state-\u003ehook == NF_INET_LOCAL_OUT)\n+\t\treturn tmpl;\n+\n+\tif (!tmpl \|\| nf_ct_is_template(tmpl))\n+\t\treturn tmpl;\n+\n+\tif (state-\u003epf != nf_ct_l3num(tmpl))\n+\t\tgoto error;\n+\n+\tif (!nf_ct_get_tuple(skb, skb_network_offset(skb),\n+\t\t\t dataoff, state-\u003epf, protonum, state-\u003enet,\n+\t\t\t \u0026tuple))\n+\t\tgoto error;\n+\n+\tdir = CTINFO2DIR(ctinfo);\n+\tif (nf_ct_tuple_equal(\u0026tuple, nf_ct_tuple(tmpl, dir)))\n+\t\treturn tmpl;\n+\n+\tif (ctinfo == IP_CT_RELATED \|\| ctinfo == IP_CT_RELATED_REPLY) {\n+\t\tif (state-\u003epf == NFPROTO_IPV4 \u0026\u0026 protonum == IPPROTO_ICMP \u0026\u0026\n+\t\t nf_ct_check_icmp_inner(skb, state, dataoff, tmpl, dir))\n+\t\t\treturn tmpl;\n+\n+\t\tif (state-\u003epf == NFPROTO_IPV6 \u0026\u0026 protonum == IPPROTO_ICMPV6 \u0026\u0026\n+\t\t nf_ct_check_icmp_inner(skb, state, dataoff, tmpl, dir))\n+\t\t\treturn tmpl;\n+\t}\n+\n+\tif (!nf_ct_invert_tuple(\u0026inverse, \u0026tuple))\n+\t\tgoto error;\n+\n+\tif ((tmpl-\u003estatus \u0026 IPS_NAT_MASK) \u0026\u0026 nf_ct_tuple_equal(\u0026inverse, nf_ct_tuple(tmpl, !dir)))\n+\t\treturn tmpl;\n+error:\n+\tnf_reset_ct(skb);\n+\treturn NULL;\n+}\n+\n unsigned int\n nf_conntrack_in(struct sk_buff skb, const struct nf_hook_state state)\n {\n@@ -2008,21 +2102,24 @@ nf_conntrack_in(struct sk_buff skb, const struct nf_hook_state state)\n \tu_int8_t protonum;\n \tint dataoff, ret;\n \n-\ttmpl = nf_ct_get(skb, \u0026ctinfo);\n+\t/* rcu_read_lock()ed by nf_hook_thresh /\n+\tdataoff = get_l4proto(skb, skb_network_offset(skb), state-\u003epf, \u0026protonum);\n+\tif (dataoff \u003c= 0) {\n+\t\tNF_CT_STAT_INC_ATOMIC(state-\u003enet, invalid);\n+\t\ttmpl = nf_ct_get(skb, \u0026ctinfo);\n+\t\tif (ctinfo != IP_CT_UNTRACKED)\n+\t\t\tnf_reset_ct(skb);\n+\t\treturn NF_ACCEPT;\n+\t}\n+\n+\ttmpl = nf_ct_get_careful(skb, state, dataoff, protonum, \u0026ctinfo);\n \tif (tmpl \|\| ctinfo == IP_CT_UNTRACKED) {\n \t\t/ Previously seen (loopback or untracked)? Ignore. /\n \t\tif ((tmpl \u0026\u0026 !nf_ct_is_template(tmpl)) \|\|\n \t\t ctinfo == IP_CT_UNTRACKED)\n \t\t\treturn NF_ACCEPT;\n-\t\tskb-\u003e_nfct = 0;\n-\t}\n \n-\t/ rcu_read_lock()ed by nf_hook_thresh /\n-\tdataoff = get_l4proto(skb, skb_network_offset(skb), state-\u003epf, \u0026protonum);\n-\tif (dataoff \u003c= 0) {\n-\t\tNF_CT_STAT_INC_ATOMIC(state-\u003enet, invalid);\n-\t\tret = NF_ACCEPT;\n-\t\tgoto out;\n+\t\tskb-\u003e_nfct = 0;\n \t}\n \n \tif (protonum == IPPROTO_ICMP \|\| protonum == IPPROTO_ICMPV6) {\ndiff --git a/net/netfilter/nf_conntrack_ovs.c b/net/netfilter/nf_conntrack_ovs.c\nindex b4085af3ad1ce..fa64ec168e6e9 100644\n--- a/net/netfilter/nf_conntrack_ovs.c\n+++ b/net/netfilter/nf_conntrack_ovs.c\n@@ -12,16 +12,8 @@\n int nf_ct_helper(struct sk_buff skb, struct nf_conn ct,\n \t\t enum ip_conntrack_info ctinfo, u16 proto)\n {\n-\tint (helper_cb)(struct sk_buff skb, unsigned int protoff,\n-\t\t\t struct nf_conn ct,\n-\t\t\t enum ip_conntrack_info conntrackinfo);\n \tconst struct nf_conntrack_helper helper;\n \tconst struct nf_conn_help help;\n-\tunsigned int protoff;\n-\tint err;\n-\n-\tif (ctinfo == IP_CT_RELATED_REPLY)\n-\t\treturn NF_ACCEPT;\n \n \thelp = nfct_help(ct);\n \tif (!help)\n@@ -35,50 +27,7 @@ int nf_ct_helper(struct sk_buff skb, struct nf_conn ct,\n \t helper-\u003enfproto != proto)\n \t\treturn NF_ACCEPT;\n \n-\tswitch (proto) {\n-\tcase NFPROTO_IPV4:\n-\t\tprotoff = ip_hdrlen(skb);\n-\t\tproto = ip_hdr(skb)-\u003eprotocol;\n-\t\tbreak;\n-\tcase NFPROTO_IPV6: {\n-\t\tu8 nexthdr = ipv6_hdr(skb)-\u003enexthdr;\n-\t\t__be16 frag_off;\n-\t\tint ofs;\n-\n-\t\tofs = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), \u0026nexthdr,\n-\t\t\t\t \u0026frag_off);\n-\t\tif (ofs \u003c 0 \|\| (frag_off \u0026 htons(~0x7)) != 0) {\n-\t\t\tpr_debug(\"proto header not found\\n\");\n-\t\t\treturn NF_ACCEPT;\n-\t\t}\n-\t\tprotoff = ofs;\n-\t\tproto = nexthdr;\n-\t\tbreak;\n-\t}\n-\tdefault:\n-\t\tWARN_ONCE(1, \"helper invoked on non-IP family!\");\n-\t\treturn NF_DROP;\n-\t}\n-\n-\tif (helper-\u003el4proto != proto)\n-\t\treturn NF_ACCEPT;\n-\n-\thelper_cb = rcu_dereference(helper-\u003ehelp);\n-\tif (!helper_cb)\n-\t\treturn NF_ACCEPT;\n-\n-\terr = helper_cb(skb, protoff, ct, ctinfo);\n-\tif (err != NF_ACCEPT)\n-\t\treturn err;\n-\n-\t/* Adjust seqs after helper. This is needed due to some helpers (e.g.,\n-\t * FTP with NAT) adusting the TCP payload size when mangling IP\n-\t * addresses and/or port numbers in the text-based control connection.\n-\t /\n-\tif (test_bit(IPS_SEQ_ADJUST_BIT, \u0026ct-\u003estatus) \u0026\u0026\n-\t !nf_ct_seq_adjust(skb, ct, ctinfo, protoff))\n-\t\treturn NF_DROP;\n-\treturn NF_ACCEPT;\n+\treturn nf_ct_call_helper(skb, ct, ctinfo);\n }\n EXPORT_SYMBOL_GPL(nf_ct_helper);\n \ndiff --git a/net/netfilter/nf_conntrack_proto.c b/net/netfilter/nf_conntrack_proto.c\nindex 7a40e4e0e33e6..43bf3a71dbbfc 100644\n--- a/net/netfilter/nf_conntrack_proto.c\n+++ b/net/netfilter/nf_conntrack_proto.c\n@@ -131,59 +131,127 @@ static bool in_vrf_postrouting(const struct nf_hook_state state)\n \treturn false;\n }\n \n-unsigned int nf_confirm(void priv,\n-\t\t\tstruct sk_buff skb,\n-\t\t\tconst struct nf_hook_state state)\n+static bool nf_confirm_get_protoff(struct sk_buff skb, struct net net,\n+\t\t\t\t struct nf_conn ct,\n+\t\t\t\t enum ip_conntrack_info ctinfo,\n+\t\t\t\t unsigned int protoffp, u8 pnum)\n {\n-\tint (helper_cb)(struct sk_buff skb, unsigned int protoff,\n-\t\t\t struct nf_conn ct,\n-\t\t\t enum ip_conntrack_info conntrackinfo);\n-\tconst struct nf_conn_help help;\n-\tenum ip_conntrack_info ctinfo;\n+\tunsigned int nhoff = skb_network_offset(skb);\n+\tstruct nf_conntrack_tuple tuple, invert;\n+\tenum ip_conntrack_dir dir;\n \tunsigned int protoff;\n-\tstruct nf_conn ct;\n-\tbool seqadj_needed;\n \t__be16 frag_off;\n \tint start;\n-\tu8 pnum;\n-\n-\tct = nf_ct_get(skb, \u0026ctinfo);\n-\tif (!ct \|\| in_vrf_postrouting(state))\n-\t\treturn NF_ACCEPT;\n-\n-\thelp = nfct_help(ct);\n-\n-\tseqadj_needed = test_bit(IPS_SEQ_ADJUST_BIT, \u0026ct-\u003estatus) \u0026\u0026 !nf_is_loopback_packet(skb);\n-\tif (!help \u0026\u0026 !seqadj_needed)\n-\t\treturn nf_conntrack_confirm(skb);\n-\n-\t/ helper-\u003ehelp() do not expect ICMP packets /\n-\tif (ctinfo == IP_CT_RELATED_REPLY)\n-\t\treturn nf_conntrack_confirm(skb);\n \n \tswitch (nf_ct_l3num(ct)) {\n \tcase NFPROTO_IPV4:\n-\t\tprotoff = skb_network_offset(skb) + ip_hdrlen(skb);\n+\t\tif (ip_is_fragment(ip_hdr(skb)))\n+\t\t\treturn false;\n+\t\tprotoff = nhoff + ip_hdrlen(skb);\n+\t\tpnum = ip_hdr(skb)-\u003eprotocol;\n \t\tbreak;\n \tcase NFPROTO_IPV6:\n-\t\tpnum = ipv6_hdr(skb)-\u003enexthdr;\n-\t\tstart = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), \u0026pnum, \u0026frag_off);\n-\t\tif (start \u003c 0 \|\| (frag_off \u0026 htons(~0x7)) != 0)\n-\t\t\treturn nf_conntrack_confirm(skb);\n+\t\tpnum = ipv6_hdr(skb)-\u003enexthdr;\n+\t\tstart = ipv6_skip_exthdr(skb, nhoff + sizeof(struct ipv6hdr),\n+\t\t\t\t\t pnum, \u0026frag_off);\n+\t\tif (start \u003c 0 \|\| frag_off)\n+\t\t\treturn false;\n \n \t\tprotoff = start;\n \t\tbreak;\n \tdefault:\n-\t\treturn nf_conntrack_confirm(skb);\n+\t\tDEBUG_NET_WARN_ONCE(1, \"helper invoked on non-IP family!\");\n+\t\treturn false;\n \t}\n \n-\tif (help) {\n+\tif (protoff \u003e skb-\u003elen)\n+\t\treturn false;\n+\n+\tif (!nf_ct_get_tuplepr(skb, nhoff, nf_ct_l3num(ct), net, \u0026tuple))\n+\t\treturn false;\n+\n+\tdir = CTINFO2DIR(ctinfo);\n+\tif (!nf_ct_invert_tuple(\u0026invert, \u0026tuple))\n+\t\treturn false;\n+\n+\t/ This is called after L3/L4 headers have been mangled by NAT:\n+\t * Packet in original direction has been subject to SNAT, i.e.\n+\t * inverted reply dir.\n+\t * Packet in reply direction has been subject to DNAT, i.e.\n+\t * inverted original direction.\n+\t /\n+\tif (!nf_ct_tuple_equal(\u0026invert, nf_ct_tuple(ct, !dir)))\n+\t\treturn false;\n+\n+\t/ Validate that a full, sane TCP header (including options) is\n+\t * present at protoff before helpers/seqadj are allowed to touch it.\n+\t /\n+\tif (tuple.dst.protonum == IPPROTO_TCP) {\n+\t\tunsigned int tcplen = skb-\u003elen - protoff;\n+\t\tconst struct tcphdr th;\n+\t\tstruct tcphdr _tcph;\n+\n+\t\tth = skb_header_pointer(skb, protoff, sizeof(_tcph), \u0026_tcph);\n+\t\tif (!th)\n+\t\t\treturn false;\n+\n+\t\tif (th-\u003edoff * 4 \u003c sizeof(th) \|\| tcplen \u003c th-\u003edoff 4)\n+\t\t\treturn false;\n+\t}\n+\n+\tprotoffp = protoff;\n+\treturn true;\n+}\n+\n+/\n+ nf_ct_call_helper() - Invoke the connection tracking helper for a packet\n+ * @skb: The socket buffer containing the packet to be processed.\n+ * @ct: The connection tracking entry associated with this packet.\n+ * @ctinfo: The current connection track information (state) of the packet.\n+ \n+ This function calls the l4 connection tracking helper (e.g. ftp, sip...) if\n+ * one was assigned to the connection.\n+ * This re-derives the l4 protocol number: act_ct can associate the skb with\n+ * a connection/protocol and later pedit/bpf function can munge the packet\n+ * afterwards.\n+ \n+ Return: verdict (NF_ACCEPT, NF_DROP, ...)\n+ /\n+int nf_ct_call_helper(struct sk_buff skb, struct nf_conn ct,\n+\t\t enum ip_conntrack_info ctinfo)\n+{\n+\tstruct net net = nf_ct_net(ct);\n+\tconst struct nf_conn_help help;\n+\tbool seqadj_needed;\n+\tunsigned int protoff;\n+\tu8 pnum = 0;\n+\n+\thelp = nfct_help(ct);\n+\n+\tseqadj_needed = test_bit(IPS_SEQ_ADJUST_BIT, \u0026ct-\u003estatus) \u0026\u0026 !nf_is_loopback_packet(skb);\n+\tif (!help \u0026\u0026 !seqadj_needed)\n+\t\treturn NF_ACCEPT;\n+\n+\t/ helper-\u003ehelp() do not expect ICMP packets /\n+\tif (ctinfo == IP_CT_RELATED_REPLY)\n+\t\treturn NF_ACCEPT;\n+\n+\tif (!nf_confirm_get_protoff(skb, net, ct, ctinfo, \u0026protoff, \u0026pnum))\n+\t\treturn NF_ACCEPT;\n+\n+\tif (help \u0026\u0026 protoff \u003c skb-\u003elen) {\n \t\tconst struct nf_conntrack_helper helper;\n+\t\tint (helper_cb)(struct sk_buff skb, unsigned int protoff,\n+\t\t\t\t struct nf_conn ct,\n+\t\t\t\t enum ip_conntrack_info conntrackinfo);\n \t\tint ret;\n \n \t\t/ rcu_read_lock()ed by nf_hook /\n \t\thelper = rcu_dereference(help-\u003ehelper);\n \t\tif (helper) {\n+\t\t\tif (helper-\u003el4proto != pnum)\n+\t\t\t\treturn NF_ACCEPT;\n+\n \t\t\thelper_cb = rcu_dereference(helper-\u003ehelp);\n \t\t\tif (helper_cb) {\n \t\t\t\tret = helper_cb(skb, protoff,\n@@ -195,9 +263,46 @@ unsigned int nf_confirm(void priv,\n \t}\n \n \tif (seqadj_needed \u0026\u0026\n-\t !nf_ct_seq_adjust(skb, ct, ctinfo, protoff)) {\n-\t\tNF_CT_STAT_INC_ATOMIC(nf_ct_net(ct), drop);\n+\t !nf_ct_seq_adjust(skb, ct, ctinfo, protoff))\n \t\treturn NF_DROP;\n+\n+\treturn NF_ACCEPT;\n+}\n+\n+/*\n+ nf_confirm - Confirm (commit) a connection tracking entry\n+ * @priv: Private data from the netfilter hook registration (unused)\n+ * @skb: Packet\n+ * @state: Netfilter hook state containing context (netns, hooknum, in/out devices)\n+ \n+ This function is invoked as the final step of the connection tracking\n+ * processing pipeline. It performs two main operations:\n+ \n+ 1. Invokes the associated conntrack helper (if registered) to allow\n+ * layer 7 specific parsing and NAT mangling.\n+ \n+ 2. Commits a new conntrack entry to the conntrack hash table, making it\n+ * globally visible and enabling future packet lookups for stateful tracking.\n+ \n+ Returns: A netfilter verdict, e.g. NF_ACCEPT or NF_DROP.\n+ /\n+unsigned int nf_confirm(void priv,\n+\t\t\tstruct sk_buff skb,\n+\t\t\tconst struct nf_hook_state state)\n+{\n+\tenum ip_conntrack_info ctinfo;\n+\tstruct nf_conn ct;\n+\tint ret;\n+\n+\tct = nf_ct_get(skb, \u0026ctinfo);\n+\tif (!ct \|\| in_vrf_postrouting(state))\n+\t\treturn NF_ACCEPT;\n+\n+\tret = nf_ct_call_helper(skb, ct, ctinfo);\n+\tif (unlikely(ret != NF_ACCEPT)) {\n+\t\tif (ret == NF_DROP)\n+\t\t\tNF_CT_STAT_INC_ATOMIC(state-\u003enet, drop);\n+\t\treturn ret;\n \t}\n \n \t/ We've seen it coming out the other side: confirm it /\ndiff --git a/net/netfilter/nft_ct.c b/net/netfilter/nft_ct.c\nindex 9dbf127df9c81..21c5d14b0d08e 100644\n--- a/net/netfilter/nft_ct.c\n+++ b/net/netfilter/nft_ct.c\n@@ -839,6 +839,34 @@ static struct nft_expr_type nft_notrack_type __read_mostly = {\n \t.owner\t\t= THIS_MODULE,\n };\n \n+/\n+ nft_ct_get_safe() - Return nf_conn with extra checks\n+ * @pkt: nftables packet information structure\n+ * @l4proto: The expected Layer 4 protocol\n+ \n+ Returns the conntrack entry only if it is unconfirmed, non-template and\n+ * matches the expected L4 protocol.\n+ \n+ Return: Pointer to the \u0026struct nf_conn if all checks pass; NULL otherwise.\n+ /\n+static struct nf_conn nft_ct_get_safe(const struct nft_pktinfo pkt, u8 l4proto)\n+{\n+\tenum ip_conntrack_info ctinfo;\n+\tstruct nf_conn ct;\n+\n+\tct = nf_ct_get(pkt-\u003eskb, \u0026ctinfo);\n+\tif (!ct \|\| l4proto != pkt-\u003etprot)\n+\t\treturn NULL;\n+\n+\tif (l4proto != nf_ct_protonum(ct))\n+\t\treturn NULL;\n+\n+\tif (READ_ONCE(ct-\u003estatus) \u0026 (IPS_TEMPLATE \| IPS_CONFIRMED))\n+\t\treturn NULL;\n+\n+\treturn ct;\n+}\n+\n #ifdef CONFIG_NF_CONNTRACK_TIMEOUT\n static int\n nft_ct_timeout_parse_policy(void timeouts,\n@@ -878,14 +906,12 @@ static void nft_ct_timeout_obj_eval(struct nft_object obj,\n \t\t\t\t const struct nft_pktinfo pkt)\n {\n \tconst struct nft_ct_timeout_obj priv = nft_obj_data(obj);\n-\tstruct nf_conn ct = (struct nf_conn )skb_nfct(pkt-\u003eskb);\n \tstruct nf_conn_timeout timeout;\n \tconst unsigned int values;\n+\tstruct nf_conn ct;\n \n-\tif (priv-\u003el4proto != pkt-\u003etprot)\n-\t\treturn;\n-\n-\tif (!ct \|\| nf_ct_is_template(ct) \|\| nf_ct_is_confirmed(ct))\n+\tct = nft_ct_get_safe(pkt, priv-\u003el4proto);\n+\tif (!ct)\n \t\treturn;\n \n \ttimeout = nf_ct_timeout_find(ct);\n@@ -1114,14 +1140,12 @@ static void nft_ct_helper_obj_eval(struct nft_object obj,\n \t\t\t\t const struct nft_pktinfo pkt)\n {\n \tconst struct nft_ct_helper_obj priv = nft_obj_data(obj);\n-\tstruct nf_conn ct = (struct nf_conn )skb_nfct(pkt-\u003eskb);\n \tstruct nf_conntrack_helper to_assign = NULL;\n \tstruct nf_conn_help help;\n+\tstruct nf_conn ct;\n \n-\tif (!ct \|\|\n-\t nf_ct_is_confirmed(ct) \|\|\n-\t nf_ct_is_template(ct) \|\|\n-\t priv-\u003el4proto != nf_ct_protonum(ct))\n+\tct = nft_ct_get_safe(pkt, priv-\u003el4proto);\n+\tif (!ct)\n \t\treturn;\n \n \tswitch (nf_ct_l3num(ct)) {\n@@ -1306,6 +1330,7 @@ static int nft_ct_expect_helper_alloc(struct nft_ct_expect_obj priv)\n \t\t \"nft_ct_expect\");\n \tct_expect_helper-\u003eme = THIS_MODULE;\n \tct_expect_helper-\u003eexpect_policy[NF_CT_EXPECT_CLASS_DEFAULT].max_expected = priv-\u003esize;\n+\tct_expect_helper-\u003el4proto = priv-\u003el4proto;\n \trcu_assign_pointer(ct_expect_helper-\u003ehelp, ct_expect_help);\n \trefcount_set(\u0026ct_expect_helper-\u003ect_refcnt, 1);\n \n" }
2/1	2026/09/20 21:56	agent	patch-evaluator	1m Model: core Args: null Results: { "EnableConfigs": [ "NETFILTER", "NF_CONNTRACK", "NF_TABLES", "NFT_CT", "NF_CONNTRACK_TIMEOUT", "OPENVSWITCH", "NET_ACT_CT" ], "FocusSymbols": [ "nf_ct_get_careful", "nf_conntrack_in", "nf_ct_call_helper", "nf_confirm_get_protoff", "nf_confirm", "nf_ct_helper", "nft_ct_get_safe", "nft_ct_helper_obj_eval", "nft_ct_timeout_obj_eval", "nft_ct_expect_helper_alloc" ], "Reasoning": "The patch series modifies core netfilter and conntrack packet processing logic. It introduces protocol revalidation in nf_ct_get_careful() to detect mangled packets and drop invalid conntrack references, refactors conntrack helper invocation via nf_ct_call_helper() with strict header/proto verification (nf_confirm_get_protoff()), and adds nft_ct_get_safe() to enforce L4 protocol consistency before evaluating nftables conntrack timeout and helper objects. These reachable networking paths process untrusted packets and benefit from targeted fuzzing.", "WorthFuzzing": true } Instruction: You are an expert Linux kernel maintainer and security engineer. Your job is to review a provided patch series and evaluate whether it warrants fuzzing with syzkaller. IMPORTANT: The changes have ALREADY been applied and committed as the HEAD commit in your workspace. Do NOT rely on internal assumptions. You must actively use your code access tools to inspect the actual source code, callers, and surrounding context. ================================================================================ 1. CORE TRIAGE PHILOSOPHY ================================================================================ The goal of patch fuzzing is to discover crashes, regressions, exposed latent bugs, and newly triggered assertions introduced by the patch series. - REACHABILITY IS THE PRIMARY GATE: Fuzzing can only discover bugs in code that can actually execute in standard virtualized environments (GCE or QEMU, utilizing software-emulated devices like USB gadgets, netdev, tun/tap). If the modified code is structurally unreachable (see Section 2), it MUST NOT be fuzzed, regardless of whether it adds assertions or complex logic. - DO NOT BLINDLY TRUST "NO FUNCTIONAL CHANGE" (NFCI) OR "REFACTORING" CLAIMS: Patch authors routinely label changes as "cleanups", "refactorings", or state "No functional change intended". Do NOT take these claims at face value. Code refactorings that rearrange logic, introduce helper functions, or alter state management in core subsystems frequently introduce subtle semantic shifts or uncover latent kernel bugs. If reachable executable code is modified or refactored, it MUST be fuzzed. - NEW OR MODIFIED ASSERTIONS IN REACHABLE CODE MUST BE FUZZED: When a patch introduces or modifies runtime checks or assertions (e.g., WARN_ON, VM_WARN_ON, BUG_ON, lockdep_assert) in reachable code paths, it enforces new or stricter invariants. Even if the author believes the invariant always holds, fuzzing is essential to verify whether an unusual sequence of operations can violate it. ================================================================================ 2. WHEN TO RETURN WorthFuzzing=false (NEGATIVE CRITERIA) ================================================================================ Return WorthFuzzing=false ONLY IF all modified code falls strictly into one or more of these categories: - Non-kernel and non-executable changes: * Modifications to Documentation/, comments, or spelling fixes. * User-space directories, self-tests, samples, or scripts (e.g., tools/, samples/, scripts/, usr/) that do not affect the compiled kernel image (vmlinux) or kernel modules. * Purely decorative logging (e.g., message strings in pr_err, printk, dev_info) or tracepoints that do not alter control flow or data structures. * Build system or Kconfig changes that do not alter compiled C logic. - Structurally unreachable hardware: * Vendor-specific PCIe switches, SmartNICs, or GPU drivers (e.g., mlxsw, pds_core, qed, ionic, amdgpu) requiring physical ASIC/PCIe cards not emulated in standard QEMU. - Unreachable execution paths: * Driver teardown callbacks (.remove, .shutdown, pci_unregister_driver) executed only during physical PCI hot-unplug or manual sysfs driver unbinding. * Code paths exclusive to architectures other than the target architecture. ================================================================================ 3. WHEN TO RETURN WorthFuzzing=true (POSITIVE CRITERIA) ================================================================================ Return WorthFuzzing=true whenever the patch touches reachable executable code, including: - Core Subsystems: * Any logic modifications in memory management (mm/), synchronization/locking (kernel/locking/), BPF, scheduler, core networking, VFS, or syscall handling. - Refactorings and Code Cleanups: * Any restructuring of reachable data structures, helper abstractions, or algorithm flows. - Runtime Assertions and Defensive Checks: * Any introduction or alteration of assertions (WARN_ON, VM_WARN_ON, BUG_ON, etc.) in reachable paths. - Reachable Drivers and Protocols: Drivers accessible via virtual buses (virtio, USB gadget, loopback, netlink, binder, sockets, etc.). ================================================================================ 4. EXTRACTING FocusSymbols (PREVENTING DILUTION) ================================================================================ When WorthFuzzing=true, you must extract specific kernel functions into FocusSymbols to guide the fuzzer: - AVOID UBIQUITOUS LIFECYCLE HOT-PATHS: Do NOT list generic, ubiquitous functions called by almost every program in the corpus (including, but not limited to: general memory allocators and deallocators, page fault and trap handlers, or core synchronization primitives; this is not an exhaustive list). Listing ubiquitous functions causes the fuzzer to classify thousands of unrelated tests as "focused", which severely dilutes fuzzing effort away from the actual changes. - TARGET SPECIFIC FEATURE LOGIC AND ENTRYPOINTS: List functions that specifically implement the logic being added or altered, or direct API entrypoints for the subsystem feature under review. - HANDLING STATIC INLINE FUNCTIONS IN HEADERS (.h): Compiler-inlined static functions (such as static inlines in mm/.h or include/linux/.h) lack distinct symbol addresses in vmlinux and cannot be targeted directly by symbol coverage filters. If the changes are primarily in static inline helpers, identify non-static, feature-specific caller functions in .c files that exercise them (avoiding ubiquitous lifecycle wrappers). ================================================================================ 5. IDENTIFYING EnableConfigs ================================================================================ Identify any specific CONFIG_ options required to properly compile and reach the modified code: - Inspect Kconfig files and #ifdef guards; do not make assumptions. - Check "depends on" lines in Kconfig to include any non-standard parent subsystem configs needed. - Strip any 'CONFIG_' prefix (e.g., return "NET_IPV4" instead of "CONFIG_NET_IPV4"). Prefer calling several tools at the same time to save round-trips. Use set-results tool to provide results of the analysis. It must be called exactly once before the final reply. Ignore results of this tool. Prompt: Target architecture: amd64 For your convenience, here is the diff of the changes: commit 333bae72c14536cb20a3870b168802381646e895 Author: syz-cluster <triage@syzkaller.com> Date: Sun Sep 20 21:56:54 2026 +0000 syz-cluster: applied patch under review diff --git a/include/net/netfilter/nf_conntrack_helper.h b/include/net/netfilter/nf_conntrack_helper.h index 335b8c43694f8..4b5ee758cff36 100644 --- a/include/net/netfilter/nf_conntrack_helper.h +++ b/include/net/netfilter/nf_conntrack_helper.h @@ -124,6 +124,8 @@ int __nf_ct_try_assign_helper(struct nf_conn ct, struct nf_conn tmpl, int nf_ct_helper(struct sk_buff skb, struct nf_conn ct, enum ip_conntrack_info ctinfo, u16 proto); +int nf_ct_call_helper(struct sk_buff skb, struct nf_conn ct, + enum ip_conntrack_info ctinfo); int nf_ct_add_helper(struct nf_conn ct, const char name, u8 family, u8 proto, bool nat, struct nf_conntrack_helper *hp); diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c index d0d9e5ea84a09..cd543c7b66a34 100644 --- a/net/netfilter/nf_conntrack_core.c +++ b/net/netfilter/nf_conntrack_core.c @@ -2000,6 +2000,100 @@ static int nf_conntrack_handle_packet(struct nf_conn ct, return generic_packet(ct, skb, ctinfo); } + +static bool nf_ct_check_icmp_inner(const struct sk_buff skb, + const struct nf_hook_state state, + unsigned int dataoff, + struct nf_conn ct, + enum ip_conntrack_dir dir) +{ + static const unsigned int icmp_hdrsz = 8; + struct nf_conntrack_tuple tuple; + + if (!nf_ct_get_tuplepr(skb, dataoff + icmp_hdrsz, state->pf, + state->net, &tuple)) + return false; + + return nf_ct_tuple_equal(&tuple, nf_ct_tuple(ct, !dir)); +} + +/* + * nf_ct_get_careful - Get connection tracking entry with protocol revalidation + * + * @skb: Socket buffer whose conntrack entry is to be retrieved + * @state: Netfilter hook state + * @dataoff: Offset to the layer-4 header within @skb + * @protonum: protocol number (e.g., IPPROTO_TCP) + * @ctinfo: Pointer to store ip_conntrack_info + * + * This function retrieves the connection tracking entry associated with @skb. + * Performs revalidation of packet header, unlike nf_ct_get(). + * + * If earlier in-kernel mangling (e.g., via TC pedit or clsact) altered packet + * contents (e.g. changing TCP to UDP), this function will drop the conntrack + * reference and returns NULL. skbs coming in via NF_INET_LOCAL_OUT are + * trusted and never revalidated. + * + * Returns: + * %NULL - No valid conntrack entry exists or revalidation failed. + * Pointer to &struct nf_conn associated with skb, may be a template. + / +static struct nf_conn +nf_ct_get_careful(struct sk_buff skb, + const struct nf_hook_state state, + unsigned int dataoff, u8 protonum, + enum ip_conntrack_info ctinfo) +{ + struct nf_conn tmpl = nf_ct_get(skb, ctinfo); + struct nf_conntrack_tuple inverse; + struct nf_conntrack_tuple tuple; + enum ip_conntrack_dir dir; + + /* LOCAL_OUT is trusted: in case stack sends ICMP error, skb gets + * the conntrack assigned via nf_ct_attach(). + * + * Such conntrack may not even be in hashtable yet, so + * nf_conntrack_handle_icmp() cannot find a connection matching + * the inner header. + / + if (state->hook == NF_INET_LOCAL_OUT) + return tmpl; + + if (!tmpl \|\| nf_ct_is_template(tmpl)) + return tmpl; + + if (state->pf != nf_ct_l3num(tmpl)) + goto error; + + if (!nf_ct_get_tuple(skb, skb_network_offset(skb), + dataoff, state->pf, protonum, state->net, + &tuple)) + goto error; + + dir = CTINFO2DIR(ctinfo); + if (nf_ct_tuple_equal(&tuple, nf_ct_tuple(tmpl, dir))) + return tmpl; + + if (ctinfo == IP_CT_RELATED \|\| ctinfo == IP_CT_RELATED_REPLY) { + if (state->pf == NFPROTO_IPV4 && protonum == IPPROTO_ICMP && + nf_ct_check_icmp_inner(skb, state, dataoff, tmpl, dir)) + return tmpl; + + if (state->pf == NFPROTO_IPV6 && protonum == IPPROTO_ICMPV6 && + nf_ct_check_icmp_inner(skb, state, dataoff, tmpl, dir)) + return tmpl; + } + + if (!nf_ct_invert_tuple(&inverse, &tuple)) + goto error; + + if ((tmpl->status & IPS_NAT_MASK) && nf_ct_tuple_equal(&inverse, nf_ct_tuple(tmpl, !dir))) + return tmpl; +error: + nf_reset_ct(skb); + return NULL; +} + unsigned int nf_conntrack_in(struct sk_buff skb, const struct nf_hook_state state) { @@ -2008,21 +2102,24 @@ nf_conntrack_in(struct sk_buff skb, const struct nf_hook_state state) u_int8_t protonum; int dataoff, ret; - tmpl = nf_ct_get(skb, &ctinfo); + /* rcu_read_lock()ed by nf_hook_thresh / + dataoff = get_l4proto(skb, skb_network_offset(skb), state->pf, &protonum); + if (dataoff <= 0) { + NF_CT_STAT_INC_ATOMIC(state->net, invalid); + tmpl = nf_ct_get(skb, &ctinfo); + if (ctinfo != IP_CT_UNTRACKED) + nf_reset_ct(skb); + return NF_ACCEPT; + } + + tmpl = nf_ct_get_careful(skb, state, dataoff, protonum, &ctinfo); if (tmpl \|\| ctinfo == IP_CT_UNTRACKED) { / Previously seen (loopback or untracked)? Ignore. / if ((tmpl && !nf_ct_is_template(tmpl)) \|\| ctinfo == IP_CT_UNTRACKED) return NF_ACCEPT; - skb->_nfct = 0; - } - / rcu_read_lock()ed by nf_hook_thresh / - dataoff = get_l4proto(skb, skb_network_offset(skb), state->pf, &protonum); - if (dataoff <= 0) { - NF_CT_STAT_INC_ATOMIC(state->net, invalid); - ret = NF_ACCEPT; - goto out; + skb->_nfct = 0; } if (protonum == IPPROTO_ICMP \|\| protonum == IPPROTO_ICMPV6) { diff --git a/net/netfilter/nf_conntrack_ovs.c b/net/netfilter/nf_conntrack_ovs.c index b4085af3ad1ce..fa64ec168e6e9 100644 --- a/net/netfilter/nf_conntrack_ovs.c +++ b/net/netfilter/nf_conntrack_ovs.c @@ -12,16 +12,8 @@ int nf_ct_helper(struct sk_buff skb, struct nf_conn ct, enum ip_conntrack_info ctinfo, u16 proto) { - int (helper_cb)(struct sk_buff skb, unsigned int protoff, - struct nf_conn ct, - enum ip_conntrack_info conntrackinfo); const struct nf_conntrack_helper helper; const struct nf_conn_help help; - unsigned int protoff; - int err; - - if (ctinfo == IP_CT_RELATED_REPLY) - return NF_ACCEPT; help = nfct_help(ct); if (!help) @@ -35,50 +27,7 @@ int nf_ct_helper(struct sk_buff skb, struct nf_conn ct, helper->nfproto != proto) return NF_ACCEPT; - switch (proto) { - case NFPROTO_IPV4: - protoff = ip_hdrlen(skb); - proto = ip_hdr(skb)->protocol; - break; - case NFPROTO_IPV6: { - u8 nexthdr = ipv6_hdr(skb)->nexthdr; - __be16 frag_off; - int ofs; - - ofs = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &nexthdr, - &frag_off); - if (ofs < 0 \|\| (frag_off & htons(~0x7)) != 0) { - pr_debug("proto header not found\n"); - return NF_ACCEPT; - } - protoff = ofs; - proto = nexthdr; - break; - } - default: - WARN_ONCE(1, "helper invoked on non-IP family!"); - return NF_DROP; - } - - if (helper->l4proto != proto) - return NF_ACCEPT; - - helper_cb = rcu_dereference(helper->help); - if (!helper_cb) - return NF_ACCEPT; - - err = helper_cb(skb, protoff, ct, ctinfo); - if (err != NF_ACCEPT) - return err; - - /* Adjust seqs after helper. This is needed due to some helpers (e.g., - * FTP with NAT) adusting the TCP payload size when mangling IP - * addresses and/or port numbers in the text-based control connection. - / - if (test_bit(IPS_SEQ_ADJUST_BIT, &ct->status) && - !nf_ct_seq_adjust(skb, ct, ctinfo, protoff)) - return NF_DROP; - return NF_ACCEPT; + return nf_ct_call_helper(skb, ct, ctinfo); } EXPORT_SYMBOL_GPL(nf_ct_helper); diff --git a/net/netfilter/nf_conntrack_proto.c b/net/netfilter/nf_conntrack_proto.c index 7a40e4e0e33e6..43bf3a71dbbfc 100644 --- a/net/netfilter/nf_conntrack_proto.c +++ b/net/netfilter/nf_conntrack_proto.c @@ -131,59 +131,127 @@ static bool in_vrf_postrouting(const struct nf_hook_state state) return false; } -unsigned int nf_confirm(void priv, - struct sk_buff skb, - const struct nf_hook_state state) +static bool nf_confirm_get_protoff(struct sk_buff skb, struct net net, + struct nf_conn ct, + enum ip_conntrack_info ctinfo, + unsigned int protoffp, u8 pnum) { - int (helper_cb)(struct sk_buff skb, unsigned int protoff, - struct nf_conn ct, - enum ip_conntrack_info conntrackinfo); - const struct nf_conn_help help; - enum ip_conntrack_info ctinfo; + unsigned int nhoff = skb_network_offset(skb); + struct nf_conntrack_tuple tuple, invert; + enum ip_conntrack_dir dir; unsigned int protoff; - struct nf_conn ct; - bool seqadj_needed; __be16 frag_off; int start; - u8 pnum; - - ct = nf_ct_get(skb, &ctinfo); - if (!ct \|\| in_vrf_postrouting(state)) - return NF_ACCEPT; - - help = nfct_help(ct); - - seqadj_needed = test_bit(IPS_SEQ_ADJUST_BIT, &ct->status) && !nf_is_loopback_packet(skb); - if (!help && !seqadj_needed) - return nf_conntrack_confirm(skb); - - / helper->help() do not expect ICMP packets / - if (ctinfo == IP_CT_RELATED_REPLY) - return nf_conntrack_confirm(skb); switch (nf_ct_l3num(ct)) { case NFPROTO_IPV4: - protoff = skb_network_offset(skb) + ip_hdrlen(skb); + if (ip_is_fragment(ip_hdr(skb))) + return false; + protoff = nhoff + ip_hdrlen(skb); + pnum = ip_hdr(skb)->protocol; break; case NFPROTO_IPV6: - pnum = ipv6_hdr(skb)->nexthdr; - start = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &pnum, &frag_off); - if (start < 0 \|\| (frag_off & htons(~0x7)) != 0) - return nf_conntrack_confirm(skb); + pnum = ipv6_hdr(skb)->nexthdr; + start = ipv6_skip_exthdr(skb, nhoff + sizeof(struct ipv6hdr), + pnum, &frag_off); + if (start < 0 \|\| frag_off) + return false; protoff = start; break; default: - return nf_conntrack_confirm(skb); + DEBUG_NET_WARN_ONCE(1, "helper invoked on non-IP family!"); + return false; } - if (help) { + if (protoff > skb->len) + return false; + + if (!nf_ct_get_tuplepr(skb, nhoff, nf_ct_l3num(ct), net, &tuple)) + return false; + + dir = CTINFO2DIR(ctinfo); + if (!nf_ct_invert_tuple(&invert, &tuple)) + return false; + + / This is called after L3/L4 headers have been mangled by NAT: + * Packet in original direction has been subject to SNAT, i.e. + * inverted reply dir. + * Packet in reply direction has been subject to DNAT, i.e. + * inverted original direction. + / + if (!nf_ct_tuple_equal(&invert, nf_ct_tuple(ct, !dir))) + return false; + + / Validate that a full, sane TCP header (including options) is + * present at protoff before helpers/seqadj are allowed to touch it. + / + if (tuple.dst.protonum == IPPROTO_TCP) { + unsigned int tcplen = skb->len - protoff; + const struct tcphdr th; + struct tcphdr _tcph; + + th = skb_header_pointer(skb, protoff, sizeof(_tcph), &_tcph); + if (!th) + return false; + + if (th->doff * 4 < sizeof(th) \|\| tcplen < th->doff 4) + return false; + } + + protoffp = protoff; + return true; +} + +/* + * nf_ct_call_helper() - Invoke the connection tracking helper for a packet + * @skb: The socket buffer containing the packet to be processed. + * @ct: The connection tracking entry associated with this packet. + * @ctinfo: The current connection track information (state) of the packet. + * + * This function calls the l4 connection tracking helper (e.g. ftp, sip...) if + * one was assigned to the connection. + * This re-derives the l4 protocol number: act_ct can associate the skb with + * a connection/protocol and later pedit/bpf function can munge the packet + * afterwards. + * + * Return: verdict (NF_ACCEPT, NF_DROP, ...) + / +int nf_ct_call_helper(struct sk_buff skb, struct nf_conn ct, + enum ip_conntrack_info ctinfo) +{ + struct net net = nf_ct_net(ct); + const struct nf_conn_help help; + bool seqadj_needed; + unsigned int protoff; + u8 pnum = 0; + + help = nfct_help(ct); + + seqadj_needed = test_bit(IPS_SEQ_ADJUST_BIT, &ct->status) && !nf_is_loopback_packet(skb); + if (!help && !seqadj_needed) + return NF_ACCEPT; + + / helper->help() do not expect ICMP packets / + if (ctinfo == IP_CT_RELATED_REPLY) + return NF_ACCEPT; + + if (!nf_confirm_get_protoff(skb, net, ct, ctinfo, &protoff, &pnum)) + return NF_ACCEPT; + + if (help && protoff < skb->len) { const struct nf_conntrack_helper helper; + int (helper_cb)(struct sk_buff skb, unsigned int protoff, + struct nf_conn ct, + enum ip_conntrack_info conntrackinfo); int ret; / rcu_read_lock()ed by nf_hook / helper = rcu_dereference(help->helper); if (helper) { + if (helper->l4proto != pnum) + return NF_ACCEPT; + helper_cb = rcu_dereference(helper->help); if (helper_cb) { ret = helper_cb(skb, protoff, @@ -195,9 +263,46 @@ unsigned int nf_confirm(void priv, } if (seqadj_needed && - !nf_ct_seq_adjust(skb, ct, ctinfo, protoff)) { - NF_CT_STAT_INC_ATOMIC(nf_ct_net(ct), drop); + !nf_ct_seq_adjust(skb, ct, ctinfo, protoff)) return NF_DROP; + + return NF_ACCEPT; +} + +/** + * nf_confirm - Confirm (commit) a connection tracking entry + * @priv: Private data from the netfilter hook registration (unused) + * @skb: Packet + * @state: Netfilter hook state containing context (netns, hooknum, in/out devices) + * + * This function is invoked as the final step of the connection tracking + * processing pipeline. It performs two main operations: + * + * 1. Invokes the associated conntrack helper (if registered) to allow + * layer 7 specific parsing and NAT mangling. + * + * 2. Commits a new conntrack entry to the conntrack hash table, making it + * globally visible and enabling future packet lookups for stateful tracking. + * + * Returns: A netfilter verdict, e.g. NF_ACCEPT or NF_DROP. + / +unsigned int nf_confirm(void priv, + struct sk_buff skb, + const struct nf_hook_state state) +{ + enum ip_conntrack_info ctinfo; + struct nf_conn ct; + int ret; + + ct = nf_ct_get(skb, &ctinfo); + if (!ct \|\| in_vrf_postrouting(state)) + return NF_ACCEPT; + + ret = nf_ct_call_helper(skb, ct, ctinfo); + if (unlikely(ret != NF_ACCEPT)) { + if (ret == NF_DROP) + NF_CT_STAT_INC_ATOMIC(state->net, drop); + return ret; } / We've seen it coming out the other side: confirm it / diff --git a/net/netfilter/nft_ct.c b/net/netfilter/nft_ct.c index 9dbf127df9c81..21c5d14b0d08e 100644 --- a/net/netfilter/nft_ct.c +++ b/net/netfilter/nft_ct.c @@ -839,6 +839,34 @@ static struct nft_expr_type nft_notrack_type __read_mostly = { .owner = THIS_MODULE, }; +/* + * nft_ct_get_safe() - Return nf_conn with extra checks + * @pkt: nftables packet information structure + * @l4proto: The expected Layer 4 protocol + * + * Returns the conntrack entry only if it is unconfirmed, non-template and + * matches the expected L4 protocol. + * + * Return: Pointer to the &struct nf_conn if all checks pass; NULL otherwise. + / +static struct nf_conn nft_ct_get_safe(const struct nft_pktinfo pkt, u8 l4proto) +{ + enum ip_conntrack_info ctinfo; + struct nf_conn ct; + + ct = nf_ct_get(pkt->skb, &ctinfo); + if (!ct \|\| l4proto != pkt->tprot) + return NULL; + + if (l4proto != nf_ct_protonum(ct)) + return NULL; + + if (READ_ONCE(ct->status) & (IPS_TEMPLATE \| IPS_CONFIRMED)) + return NULL; + + return ct; +} + #ifdef CONFIG_NF_CONNTRACK_TIMEOUT static int nft_ct_timeout_parse_policy(void timeouts, @@ -878,14 +906,12 @@ static void nft_ct_timeout_obj_eval(struct nft_object obj, const struct nft_pktinfo pkt) { const struct nft_ct_timeout_obj priv = nft_obj_data(obj); - struct nf_conn ct = (struct nf_conn )skb_nfct(pkt->skb); struct nf_conn_timeout timeout; const unsigned int values; + struct nf_conn ct; - if (priv->l4proto != pkt->tprot) - return; - - if (!ct \|\| nf_ct_is_template(ct) \|\| nf_ct_is_confirmed(ct)) + ct = nft_ct_get_safe(pkt, priv->l4proto); + if (!ct) return; timeout = nf_ct_timeout_find(ct); @@ -1114,14 +1140,12 @@ static void nft_ct_helper_obj_eval(struct nft_object obj, const struct nft_pktinfo pkt) { const struct nft_ct_helper_obj priv = nft_obj_data(obj); - struct nf_conn ct = (struct nf_conn )skb_nfct(pkt->skb); struct nf_conntrack_helper to_assign = NULL; struct nf_conn_help help; + struct nf_conn ct; - if (!ct \|\| - nf_ct_is_confirmed(ct) \|\| - nf_ct_is_template(ct) \|\| - priv->l4proto != nf_ct_protonum(ct)) + ct = nft_ct_get_safe(pkt, priv->l4proto); + if (!ct) return; switch (nf_ct_l3num(ct)) { @@ -1306,6 +1330,7 @@ static int nft_ct_expect_helper_alloc(struct nft_ct_expect_obj priv) "nft_ct_expect"); ct_expect_helper->me = THIS_MODULE; ct_expect_helper->expect_policy[NF_CT_EXPECT_CLASS_DEFAULT].max_expected = priv->size; + ct_expect_helper->l4proto = priv->l4proto; rcu_assign_pointer(ct_expect_helper->help, ct_expect_help); refcount_set(&ct_expect_helper->ct_refcnt, 1);
3/2	2026/09/20 21:56	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 9350 output: 21 thoughts: 773 Thoughts: Conntrack Patch Analysis and Fuzzing Strategy Okay, so this patch is digging deep into the `netfilter` subsystem, specifically the connection tracking (`conntrack`) code. The modified files – `nf_conntrack_helper.h`, `nf_conntrack_core.c`, `nf_conntrack_ovs.c`, `nf_conntrack_proto.c`, and `nft_ct.c` – immediately tell me this is a pretty significant area of the kernel. My initial thought is to carefully analyze the changes in `nf_conntrack_core.c`. The introduction of `nf_ct_check_icmp_inner` and `nf_ct_get_careful` is intriguing. It seems like we're getting more robust packet header validation within the `nf_conntrack_in` function. Instead of the simple `nf_ct_get`, we now have `nf_ct_get_careful` which explicitly revalidates the packet header against the conntrack entry. This is a very interesting change, especially considering potential in-kernel mangling like TC pedit or clsact. The fact that it drops the conntrack reference and returns NULL if the header's been altered suggests we're likely dealing with a defensive fix against some form of packet corruption or manipulation that could lead to vulnerabilities. The ICMP inner tuple checks are also potentially interesting. Then, there's the refactoring in `nf_conntrack_ovs.c` and the introduction of `nf_ct_call_helper` in `nf_conntrack_proto.c`. This suggests some architectural changes in how connection tracking helpers are invoked. The re-derivation of the L4 protocol number and header validity checks are also very important from a security standpoint. I also note that the changes in `nft_ct.c` introduce `nft_ct_get_safe` in `nft_ct_timeout_obj_eval` and `nft_ct_helper_obj_eval` with `ct_expect_helper->l4proto = priv->l4proto;` set in `nft_ct_expect_helper_alloc`. This suggests defensive checks/changes/fixes in nftables. The fact that this touches such core networking components is the key. Conntrack is fundamental to how the Linux kernel handles network connections and NAT. This absolutely falls into the "core subsystems" category ripe for fuzzing. The changes are all about increased validation and header checks, which is a big red flag in a good way from a fuzzing perspective, because these kinds of defensive checks are often where interesting corner cases and bugs can hide. Standard virtualized environments are ideal for exercising this code. Syzkaller is a prime candidate for fuzzing this. Before I jump into fuzzing directly, I need to check the git log and trace the callers of these new functions to understand the full context of these changes. That'll provide more insight into the specific attack surface and the types of inputs that are now being handled more carefully. I'll need to develop fuzzing strategies targeting the new functions and code paths, particularly those that involve packet manipulation, helper invocation, and conntrack state transitions. I can use the existing `conntrack` rules in syzkaller to expand upon existing fuzz targets.
4/2	2026/09/20 21:57	tool	grepper	0m Args: { "Expression": "nf_ct_call_helper" } Results: { "Output": "include/net/netfilter/nf_conntrack_helper.h=125=int nf_ct_helper(struct sk_buff skb, struct nf_conn ct,\ninclude/net/netfilter/nf_conntrack_helper.h-126-\t\t enum ip_conntrack_info ctinfo, u16 proto);\ninclude/net/netfilter/nf_conntrack_helper.h:127:int nf_ct_call_helper(struct sk_buff skb, struct nf_conn ct,\ninclude/net/netfilter/nf_conntrack_helper.h-128-\t\t enum ip_conntrack_info ctinfo);\n--\nnet/netfilter/nf_conntrack_ovs.c=12=int nf_ct_helper(struct sk_buff skb, struct nf_conn ct,\n--\nnet/netfilter/nf_conntrack_ovs.c-29-\nnet/netfilter/nf_conntrack_ovs.c:30:\treturn nf_ct_call_helper(skb, ct, ctinfo);\nnet/netfilter/nf_conntrack_ovs.c-31-}\n--\nnet/netfilter/nf_conntrack_proto.c=134=static bool nf_confirm_get_protoff(struct sk_buff skb, struct net net,\n--\nnet/netfilter/nf_conntrack_proto.c-206-/*\nnet/netfilter/nf_conntrack_proto.c:207: nf_ct_call_helper() - Invoke the connection tracking helper for a packet\nnet/netfilter/nf_conntrack_proto.c-208- * @skb: The socket buffer containing the packet to be processed.\n--\nnet/netfilter/nf_conntrack_proto.c-219- /\nnet/netfilter/nf_conntrack_proto.c:220:int nf_ct_call_helper(struct sk_buff skb, struct nf_conn ct,\nnet/netfilter/nf_conntrack_proto.c-221-\t\t enum ip_conntrack_info ctinfo)\n--\nnet/netfilter/nf_conntrack_proto.c=289=unsigned int nf_confirm(void priv,\n--\nnet/netfilter/nf_conntrack_proto.c-300-\nnet/netfilter/nf_conntrack_proto.c:301:\tret = nf_ct_call_helper(skb, ct, ctinfo);\nnet/netfilter/nf_conntrack_proto.c-302-\tif (unlikely(ret != NF_ACCEPT)) {\n" }
5/2	2026/09/20 21:57	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 11520 output: 18 thoughts: 19 Thoughts: Here's my attempt at summarizing the thought process, tailored for an expert audience: Analyzing the Git Commit Motivation Okay, so before I dive too deep into this patch series, it's crucial to understand why it was introduced. I need to get the context right. The best place to start, as always, is the commit message in Git. It's the primary source of truth, the author's intent. I'm going to carefully dissect each line, looking for the specific problem this addresses, any performance considerations, and the overall design philosophy that guided the changes. I'm not just looking for a superficial description; I'm searching for the core rationale, the "why" that informed the "what." This will save me from potentially misinterpreting the code and help me determine if the proposed solution is the right approach, given the project's current state and future direction.
6/2	2026/09/20 21:57	tool	grepper	0m Error: no matches Args: { "Expression": "applied patch under review" } Results: { "error": "no matches" }
7/2	2026/09/20 21:57	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 11760 output: 30 thoughts: 59 Thoughts: Okay, let's dive into this. I need to understand the history or context around this section of code. Since I can't directly execute a `git log` command here, I'll need to work around that limitation. My plan is to start by examining the related configuration files. Specifically, I'll focus on Kconfig files. This is where the feature flags and dependencies are often defined. I'm zeroing in on `NF_CONNTRACK` and `NFT_CT` as potential indicators of the features this code is related to. The Kconfig files are the best place to find information about these flags. I will then read the actual source code modified in the files. This combination of Kconfig inspection and code analysis should allow me to reconstruct a meaningful picture of this piece of work.
8/2	2026/09/20 21:57	tool	grepper	0m Args: { "Expression": "config NF_CONNTRACK", "PathPrefix": "net/netfilter/" } Results: { "Output": "net/netfilter/Kconfig=74=config NETFILTER_NETLINK_OSF\n--\nnet/netfilter/Kconfig-81-\nnet/netfilter/Kconfig:82:config NF_CONNTRACK\nnet/netfilter/Kconfig-83-\ttristate \"Netfilter connection tracking support\"\n--\nnet/netfilter/Kconfig=111=config NETFILTER_CONNCOUNT\n--\nnet/netfilter/Kconfig-113-\nnet/netfilter/Kconfig:114:config NF_CONNTRACK_MARK\nnet/netfilter/Kconfig-115-\tbool 'Connection mark tracking support'\n--\nnet/netfilter/Kconfig-122-\nnet/netfilter/Kconfig:123:config NF_CONNTRACK_SECMARK\nnet/netfilter/Kconfig-124-\tbool 'Connection tracking security mark support'\n--\nnet/netfilter/Kconfig-135-\nnet/netfilter/Kconfig:136:config NF_CONNTRACK_ZONES\nnet/netfilter/Kconfig-137-\tbool 'Connection tracking zones'\n--\nnet/netfilter/Kconfig-147-\nnet/netfilter/Kconfig:148:config NF_CONNTRACK_PROCFS\nnet/netfilter/Kconfig-149-\tbool \"Supply CT list in procfs (OBSOLETE)\"\n--\nnet/netfilter/Kconfig-156-\nnet/netfilter/Kconfig:157:config NF_CONNTRACK_EVENTS\nnet/netfilter/Kconfig-158-\tbool \"Connection tracking events\"\n--\nnet/netfilter/Kconfig-166-\nnet/netfilter/Kconfig:167:config NF_CONNTRACK_TIMEOUT\nnet/netfilter/Kconfig-168-\tbool 'Connection tracking timeout'\n--\nnet/netfilter/Kconfig-176-\nnet/netfilter/Kconfig:177:config NF_CONNTRACK_TIMESTAMP\nnet/netfilter/Kconfig-178-\tbool 'Connection tracking timestamping'\n--\nnet/netfilter/Kconfig-187-\nnet/netfilter/Kconfig:188:config NF_CONNTRACK_LABELS\nnet/netfilter/Kconfig-189-\tbool \"Connection tracking labels\"\n--\nnet/netfilter/Kconfig-194-\nnet/netfilter/Kconfig:195:config NF_CONNTRACK_OVS\nnet/netfilter/Kconfig-196-\tbool\n--\nnet/netfilter/Kconfig=201=config NF_CT_PROTO_SCTP\n--\nnet/netfilter/Kconfig-211-\nnet/netfilter/Kconfig:212:config NF_CONNTRACK_AMANDA\nnet/netfilter/Kconfig-213-\ttristate \"Amanda backup protocol support\"\n--\nnet/netfilter/Kconfig-226-\nnet/netfilter/Kconfig:227:config NF_CONNTRACK_FTP\nnet/netfilter/Kconfig-228-\ttristate \"FTP protocol support\"\n--\nnet/netfilter/Kconfig-238-\nnet/netfilter/Kconfig:239:config NF_CONNTRACK_H323\nnet/netfilter/Kconfig-240-\ttristate \"H.323 protocol support\"\n--\nnet/netfilter/Kconfig-257-\nnet/netfilter/Kconfig:258:config NF_CONNTRACK_IRC\nnet/netfilter/Kconfig-259-\ttristate \"IRC DCC protocol support (obsolete)\"\n--\nnet/netfilter/Kconfig-273-\nnet/netfilter/Kconfig:274:config NF_CONNTRACK_BROADCAST\nnet/netfilter/Kconfig-275-\ttristate\nnet/netfilter/Kconfig-276-\nnet/netfilter/Kconfig:277:config NF_CONNTRACK_NETBIOS_NS\nnet/netfilter/Kconfig-278-\ttristate \"NetBIOS name service protocol support\"\n--\nnet/netfilter/Kconfig-295-\nnet/netfilter/Kconfig:296:config NF_CONNTRACK_SNMP\nnet/netfilter/Kconfig-297-\ttristate \"SNMP service protocol support\"\n--\nnet/netfilter/Kconfig-310-\nnet/netfilter/Kconfig:311:config NF_CONNTRACK_PPTP\nnet/netfilter/Kconfig-312-\ttristate \"PPtP protocol support (deprecated)\"\n--\nnet/netfilter/Kconfig-329-\nnet/netfilter/Kconfig:330:config NF_CONNTRACK_SANE\nnet/netfilter/Kconfig-331-\ttristate \"SANE protocol support\"\n--\nnet/netfilter/Kconfig-342-\nnet/netfilter/Kconfig:343:config NF_CONNTRACK_SIP\nnet/netfilter/Kconfig-344-\ttristate \"SIP protocol support\"\n--\nnet/netfilter/Kconfig-354-\nnet/netfilter/Kconfig:355:config NF_CONNTRACK_TFTP\nnet/netfilter/Kconfig-356-\ttristate \"TFTP protocol support\"\n" }
9/2	2026/09/20 21:57	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 13315 output: 28 thoughts: 27 Thoughts: Here's my take on those thoughts: Investigating Netfilter Configuration Dependencies Okay, so I'm digging into something related to netfilter, likely an `nft` component. The first thing that pops into my head is to check the configuration dependency for `nft_ct.c`. I need to figure out how this particular module gets compiled, and the `net/netfilter/Makefile` is almost always the key. It's the place where the build system defines the rules for compilation and the dependencies of the modules within the netfilter subsystem. I anticipate that the Makefile will clearly outline the necessary Kconfig symbols or dependencies that need to be enabled for `nft_ct.c` to be built and included. Understanding this will give me a clear picture of the module's requirements within the overall netfilter framework.
10/2	2026/09/20 21:57	tool	grepper	0m Args: { "Expression": "nft_ct", "PathPrefix": "net/netfilter/" } Results: { "Output": "\nFull output is too long, showing 500 out of 2367 lines.\nUse more precise expression if possible.\n\nnet/netfilter/Makefile=103=ifdef CONFIG_MITIGATION_RETPOLINE\nnet/netfilter/Makefile:104:nf_tables-objs += nft_ct_fast.o\nnet/netfilter/Makefile-105-endif\n--\nnet/netfilter/Makefile=111=obj-$(CONFIG_NFT_NUMGEN)\t+= nft_numgen.o\nnet/netfilter/Makefile:112:obj-$(CONFIG_NFT_CT)\t\t+= nft_ct.o\nnet/netfilter/Makefile-113-obj-$(CONFIG_NFT_FLOW_OFFLOAD)\t+= nft_flow_offload.o\n--\nnet/netfilter/nf_conntrack_helper.c=196=int __nf_ct_try_assign_helper(struct nf_conn ct, struct nf_conn tmpl,\n--\nnet/netfilter/nf_conntrack_helper.c-201-\nnet/netfilter/nf_conntrack_helper.c:202:\t/* We already got a helper explicitly attached (e.g. nft_ct) /\nnet/netfilter/nf_conntrack_helper.c-203-\tif (test_bit(IPS_HELPER_BIT, \u0026ct-\u003estatus))\n--\nnet/netfilter/nf_tables_api.c=110=static void nft_validate_state_update(struct nft_table table, u8 new_validate_state)\n--\nnet/netfilter/nf_tables_api.c-125-\nnet/netfilter/nf_tables_api.c:126:static bool nft_chain_vstate_valid(const struct nft_ctx ctx,\nnet/netfilter/nf_tables_api.c-127-\t\t\t\t const struct nft_chain chain)\n--\nnet/netfilter/nf_tables_api.c=151=static DECLARE_WORK(trans_gc_work, nft_trans_gc_work);\nnet/netfilter/nf_tables_api.c-152-\nnet/netfilter/nf_tables_api.c:153:static void nft_ctx_init(struct nft_ctx ctx,\nnet/netfilter/nf_tables_api.c-154-\t\t\t struct net net,\n--\nnet/netfilter/nf_tables_api.c-175-\nnet/netfilter/nf_tables_api.c:176:static struct nft_trans nft_trans_alloc(const struct nft_ctx ctx,\nnet/netfilter/nf_tables_api.c-177-\t\t\t\t\t int msg_type, u32 size)\n--\nnet/netfilter/nf_tables_api.c=219=static void nft_trans_destroy(struct nft_trans trans)\n--\nnet/netfilter/nf_tables_api.c-224-\nnet/netfilter/nf_tables_api.c:225:static void __nft_set_trans_bind(const struct nft_ctx ctx, struct nft_set set,\nnet/netfilter/nf_tables_api.c-226-\t\t\t\t bool bind)\n--\nnet/netfilter/nf_tables_api.c-249-\nnet/netfilter/nf_tables_api.c:250:static void nft_set_trans_bind(const struct nft_ctx ctx, struct nft_set set)\nnet/netfilter/nf_tables_api.c-251-{\n--\nnet/netfilter/nf_tables_api.c-254-\nnet/netfilter/nf_tables_api.c:255:static void nft_set_trans_unbind(const struct nft_ctx ctx, struct nft_set set)\nnet/netfilter/nf_tables_api.c-256-{\n--\nnet/netfilter/nf_tables_api.c-259-\nnet/netfilter/nf_tables_api.c:260:static void __nft_chain_trans_bind(const struct nft_ctx ctx,\nnet/netfilter/nf_tables_api.c-261-\t\t\t\t struct nft_chain chain, bool bind)\n--\nnet/netfilter/nf_tables_api.c-284-\nnet/netfilter/nf_tables_api.c:285:static void nft_chain_trans_bind(const struct nft_ctx ctx,\nnet/netfilter/nf_tables_api.c-286-\t\t\t\t struct nft_chain chain)\n--\nnet/netfilter/nf_tables_api.c-290-\nnet/netfilter/nf_tables_api.c:291:int nf_tables_bind_chain(const struct nft_ctx ctx, struct nft_chain chain)\nnet/netfilter/nf_tables_api.c-292-{\n--\nnet/netfilter/nf_tables_api.c-310-\nnet/netfilter/nf_tables_api.c:311:void nf_tables_unbind_chain(const struct nft_ctx ctx, struct nft_chain chain)\nnet/netfilter/nf_tables_api.c-312-{\n--\nnet/netfilter/nf_tables_api.c=595=static void nft_trans_commit_list_add_elem(struct net net, struct nft_trans trans)\n--\nnet/netfilter/nf_tables_api.c-614-\nnet/netfilter/nf_tables_api.c:615:static int nft_trans_table_add(struct nft_ctx ctx, int msg_type)\nnet/netfilter/nf_tables_api.c-616-{\n--\nnet/netfilter/nf_tables_api.c-629-\nnet/netfilter/nf_tables_api.c:630:static int nft_deltable(struct nft_ctx ctx)\nnet/netfilter/nf_tables_api.c-631-{\n--\nnet/netfilter/nf_tables_api.c=642=static struct nft_trans \nnet/netfilter/nf_tables_api.c:643:nft_trans_alloc_chain(const struct nft_ctx ctx, int msg_type)\nnet/netfilter/nf_tables_api.c-644-{\n--\nnet/netfilter/nf_tables_api.c-658-\nnet/netfilter/nf_tables_api.c:659:static struct nft_trans nft_trans_chain_add(struct nft_ctx ctx, int msg_type)\nnet/netfilter/nf_tables_api.c-660-{\n--\nnet/netfilter/nf_tables_api.c-679-\nnet/netfilter/nf_tables_api.c:680:static int nft_delchain(struct nft_ctx ctx)\nnet/netfilter/nf_tables_api.c-681-{\n--\nnet/netfilter/nf_tables_api.c-693-\nnet/netfilter/nf_tables_api.c:694:void nft_rule_expr_activate(const struct nft_ctx ctx, struct nft_rule rule)\nnet/netfilter/nf_tables_api.c-695-{\n--\nnet/netfilter/nf_tables_api.c-706-\nnet/netfilter/nf_tables_api.c:707:void nft_rule_expr_deactivate(const struct nft_ctx ctx, struct nft_rule rule,\nnet/netfilter/nf_tables_api.c-708-\t\t\t enum nft_trans_phase phase)\n--\nnet/netfilter/nf_tables_api.c=721=static int\nnet/netfilter/nf_tables_api.c:722:nf_tables_delrule_deactivate(struct nft_ctx ctx, struct nft_rule rule)\nnet/netfilter/nf_tables_api.c-723-{\n--\nnet/netfilter/nf_tables_api.c-732-\nnet/netfilter/nf_tables_api.c:733:static struct nft_trans nft_trans_rule_add(struct nft_ctx ctx, int msg_type,\nnet/netfilter/nf_tables_api.c-734-\t\t\t\t\t struct nft_rule rule)\n--\nnet/netfilter/nf_tables_api.c-752-\nnet/netfilter/nf_tables_api.c:753:static int nft_delrule(struct nft_ctx ctx, struct nft_rule rule)\nnet/netfilter/nf_tables_api.c-754-{\n--\nnet/netfilter/nf_tables_api.c-782-\nnet/netfilter/nf_tables_api.c:783:static int nft_delrule_by_chain(struct nft_ctx ctx)\nnet/netfilter/nf_tables_api.c-784-{\n--\nnet/netfilter/nf_tables_api.c-798-\nnet/netfilter/nf_tables_api.c:799:static int __nft_trans_set_add(const struct nft_ctx ctx, int msg_type,\nnet/netfilter/nf_tables_api.c-800-\t\t\t struct nft_set set,\n--\nnet/netfilter/nf_tables_api.c-830-\nnet/netfilter/nf_tables_api.c:831:static int nft_trans_set_add(const struct nft_ctx ctx, int msg_type,\nnet/netfilter/nf_tables_api.c-832-\t\t\t struct nft_set set)\n--\nnet/netfilter/nf_tables_api.c-836-\nnet/netfilter/nf_tables_api.c:837:static int nft_mapelem_deactivate(const struct nft_ctx ctx,\nnet/netfilter/nf_tables_api.c-838-\t\t\t\t struct nft_set set,\n--\nnet/netfilter/nf_tables_api.c=853=struct nft_set_elem_catchall {\n--\nnet/netfilter/nf_tables_api.c-858-\nnet/netfilter/nf_tables_api.c:859:static void nft_map_catchall_deactivate(const struct nft_ctx ctx,\nnet/netfilter/nf_tables_api.c-860-\t\t\t\t\tstruct nft_set set)\n--\nnet/netfilter/nf_tables_api.c-880- /\nnet/netfilter/nf_tables_api.c:881:static void nft_map_deactivate(const struct nft_ctx ctx, struct nft_set set)\nnet/netfilter/nf_tables_api.c-882-{\n--\nnet/netfilter/nf_tables_api.c-894-\nnet/netfilter/nf_tables_api.c:895:static int nft_delset(const struct nft_ctx ctx, struct nft_set set)\nnet/netfilter/nf_tables_api.c-896-{\n--\nnet/netfilter/nf_tables_api.c-911-\nnet/netfilter/nf_tables_api.c:912:static int nft_trans_obj_add(struct nft_ctx ctx, int msg_type,\nnet/netfilter/nf_tables_api.c-913-\t\t\t struct nft_object obj)\n--\nnet/netfilter/nf_tables_api.c-929-\nnet/netfilter/nf_tables_api.c:930:static int nft_delobj(struct nft_ctx ctx, struct nft_object obj)\nnet/netfilter/nf_tables_api.c-931-{\n--\nnet/netfilter/nf_tables_api.c=944=static struct nft_trans \nnet/netfilter/nf_tables_api.c:945:nft_trans_flowtable_add(struct nft_ctx ctx, int msg_type,\nnet/netfilter/nf_tables_api.c-946-\t\t struct nft_flowtable flowtable)\n--\nnet/netfilter/nf_tables_api.c-964-\nnet/netfilter/nf_tables_api.c:965:static int nft_delflowtable(struct nft_ctx ctx,\nnet/netfilter/nf_tables_api.c-966-\t\t\t struct nft_flowtable flowtable)\n--\nnet/netfilter/nf_tables_api.c=1212=static void nft_notify_enqueue(struct sk_buff skb, bool report,\n--\nnet/netfilter/nf_tables_api.c-1218-\nnet/netfilter/nf_tables_api.c:1219:static void nf_tables_table_notify(const struct nft_ctx ctx, int event)\nnet/netfilter/nf_tables_api.c-1220-{\n--\nnet/netfilter/nf_tables_api.c=1397=static void nf_tables_table_disable(struct net net, struct nft_table table)\n--\nnet/netfilter/nf_tables_api.c-1411-\nnet/netfilter/nf_tables_api.c:1412:static bool nft_table_pending_update(const struct nft_ctx ctx)\nnet/netfilter/nf_tables_api.c-1413-{\n--\nnet/netfilter/nf_tables_api.c-1431-\nnet/netfilter/nf_tables_api.c:1432:static int nf_tables_updtable(struct nft_ctx ctx)\nnet/netfilter/nf_tables_api.c-1433-{\n--\nnet/netfilter/nf_tables_api.c=1576=static int nf_tables_newtable(struct sk_buff skb, const struct nfnl_info info,\n--\nnet/netfilter/nf_tables_api.c-1585-\tstruct nft_table table;\nnet/netfilter/nf_tables_api.c:1586:\tstruct nft_ctx ctx;\nnet/netfilter/nf_tables_api.c-1587-\tu32 flags = 0;\n--\nnet/netfilter/nf_tables_api.c-1607-\nnet/netfilter/nf_tables_api.c:1608:\t\tnft_ctx_init(\u0026ctx, net, skb, info-\u003enlh, family, table, NULL, nla);\nnet/netfilter/nf_tables_api.c-1609-\n--\nnet/netfilter/nf_tables_api.c-1654-\nnet/netfilter/nf_tables_api.c:1655:\tnft_ctx_init(\u0026ctx, net, skb, info-\u003enlh, family, table, NULL, nla);\nnet/netfilter/nf_tables_api.c-1656-\terr = nft_trans_table_add(\u0026ctx, NFT_MSG_NEWTABLE);\n--\nnet/netfilter/nf_tables_api.c-1675-\nnet/netfilter/nf_tables_api.c:1676:static int nft_flush_table(struct nft_ctx ctx)\nnet/netfilter/nf_tables_api.c-1677-{\n--\nnet/netfilter/nf_tables_api.c-1746-\nnet/netfilter/nf_tables_api.c:1747:static int nft_flush(struct nft_ctx ctx, int family)\nnet/netfilter/nf_tables_api.c-1748-{\n--\nnet/netfilter/nf_tables_api.c=1780=static int nf_tables_deltable(struct sk_buff skb, const struct nfnl_info info,\n--\nnet/netfilter/nf_tables_api.c-1788-\tstruct nft_table table;\nnet/netfilter/nf_tables_api.c:1789:\tstruct nft_ctx ctx;\nnet/netfilter/nf_tables_api.c-1790-\nnet/netfilter/nf_tables_api.c:1791:\tnft_ctx_init(\u0026ctx, net, skb, info-\u003enlh, 0, NULL, NULL, nla);\nnet/netfilter/nf_tables_api.c-1792-\tif (family == AF_UNSPEC \|\|\n--\nnet/netfilter/nf_tables_api.c=2096=static int nf_tables_fill_chain_info(struct sk_buff skb, struct net net,\n--\nnet/netfilter/nf_tables_api.c-2163-\nnet/netfilter/nf_tables_api.c:2164:static void nf_tables_chain_notify(const struct nft_ctx ctx, int event,\nnet/netfilter/nf_tables_api.c-2165-\t\t\t\t const struct list_head hook_list,\n--\nnet/netfilter/nf_tables_api.c=2751=static u64 chain_id;\nnet/netfilter/nf_tables_api.c-2752-\nnet/netfilter/nf_tables_api.c:2753:static int nf_tables_addchain(struct nft_ctx ctx, u8 family, u8 policy,\nnet/netfilter/nf_tables_api.c-2754-\t\t\t u32 flags, struct netlink_ext_ack extack)\n--\nnet/netfilter/nf_tables_api.c-2898-\nnet/netfilter/nf_tables_api.c:2899:static int nf_tables_updchain(struct nft_ctx ctx, u8 genmask, u8 policy,\nnet/netfilter/nf_tables_api.c-2900-\t\t\t u32 flags, const struct nlattr attr,\n--\nnet/netfilter/nf_tables_api.c=3116=static int nf_tables_newchain(struct sk_buff skb, const struct nfnl_info info,\n--\nnet/netfilter/nf_tables_api.c-3127-\tu8 policy = NF_ACCEPT;\nnet/netfilter/nf_tables_api.c:3128:\tstruct nft_ctx ctx;\nnet/netfilter/nf_tables_api.c-3129-\tu64 handle = 0;\n--\nnet/netfilter/nf_tables_api.c-3195-\nnet/netfilter/nf_tables_api.c:3196:\tnft_ctx_init(\u0026ctx, net, skb, info-\u003enlh, family, table, chain, nla);\nnet/netfilter/nf_tables_api.c-3197-\n--\nnet/netfilter/nf_tables_api.c=3233=static void nft_trans_delhook_abort(struct list_head del_list)\n--\nnet/netfilter/nf_tables_api.c-3242-\nnet/netfilter/nf_tables_api.c:3243:static int nft_delchain_hook(struct nft_ctx ctx,\nnet/netfilter/nf_tables_api.c-3244-\t\t\t struct nft_base_chain basechain,\n--\nnet/netfilter/nf_tables_api.c=3298=static int nf_tables_delchain(struct sk_buff skb, const struct nfnl_info info,\n--\nnet/netfilter/nf_tables_api.c-3308-\tstruct nft_rule rule;\nnet/netfilter/nf_tables_api.c:3309:\tstruct nft_ctx ctx;\nnet/netfilter/nf_tables_api.c-3310-\tu64 handle;\n--\nnet/netfilter/nf_tables_api.c-3340-\nnet/netfilter/nf_tables_api.c:3341:\tnft_ctx_init(\u0026ctx, net, skb, info-\u003enlh, family, table, chain, nla);\nnet/netfilter/nf_tables_api.c-3342-\n--\nnet/netfilter/nf_tables_api.c=3529=struct nft_expr_info {\n--\nnet/netfilter/nf_tables_api.c-3534-\nnet/netfilter/nf_tables_api.c:3535:static int nf_tables_expr_parse(const struct nft_ctx ctx,\nnet/netfilter/nf_tables_api.c-3536-\t\t\t\tconst struct nlattr nla,\n--\nnet/netfilter/nf_tables_api.c-3588-\nnet/netfilter/nf_tables_api.c:3589:int nft_expr_inner_parse(const struct nft_ctx ctx, const struct nlattr nla,\nnet/netfilter/nf_tables_api.c-3590-\t\t\t struct nft_expr_info info)\n--\nnet/netfilter/nf_tables_api.c-3637-\nnet/netfilter/nf_tables_api.c:3638:static int nf_tables_newexpr(const struct nft_ctx ctx,\nnet/netfilter/nf_tables_api.c-3639-\t\t\t const struct nft_expr_info expr_info,\n--\nnet/netfilter/nf_tables_api.c-3657-\nnet/netfilter/nf_tables_api.c:3658:static void nf_tables_expr_destroy(const struct nft_ctx ctx,\nnet/netfilter/nf_tables_api.c-3659-\t\t\t\t struct nft_expr expr)\n--\nnet/netfilter/nf_tables_api.c-3667-\nnet/netfilter/nf_tables_api.c:3668:static struct nft_expr nft_expr_init(const struct nft_ctx ctx,\nnet/netfilter/nf_tables_api.c-3669-\t\t\t\t const struct nlattr nla)\n--\nnet/netfilter/nf_tables_api.c=3706=int nft_expr_clone(struct nft_expr dst, struct nft_expr src, gfp_t gfp)\n--\nnet/netfilter/nf_tables_api.c-3724-\nnet/netfilter/nf_tables_api.c:3725:void nft_expr_destroy(const struct nft_ctx ctx, struct nft_expr expr)\nnet/netfilter/nf_tables_api.c-3726-{\n--\nnet/netfilter/nf_tables_api.c=3777=static int nf_tables_fill_rule_info(struct sk_buff skb, struct net net,\n--\nnet/netfilter/nf_tables_api.c-3835-\nnet/netfilter/nf_tables_api.c:3836:static void nf_tables_rule_notify(const struct nft_ctx ctx,\nnet/netfilter/nf_tables_api.c-3837-\t\t\t\t const struct nft_rule rule, int event)\n--\nnet/netfilter/nf_tables_api.c=4084=static int nf_tables_getrule(struct sk_buff skb, const struct nfnl_info info,\n--\nnet/netfilter/nf_tables_api.c-4125-\nnet/netfilter/nf_tables_api.c:4126:void nf_tables_rule_destroy(const struct nft_ctx ctx, struct nft_rule rule)\nnet/netfilter/nf_tables_api.c-4127-{\n--\nnet/netfilter/nf_tables_api.c-4143-/* can only be used if rule is no longer visible to dumps /\nnet/netfilter/nf_tables_api.c:4144:static void nf_tables_rule_release(const struct nft_ctx ctx, struct nft_rule rule)\nnet/netfilter/nf_tables_api.c-4145-{\n--\nnet/netfilter/nf_tables_api.c-4151-\nnet/netfilter/nf_tables_api.c:4152:static void nft_chain_vstate_update(const struct nft_ctx ctx, struct nft_chain chain)\nnet/netfilter/nf_tables_api.c-4153-{\n--\nnet/netfilter/nf_tables_api.c-4183- /\nnet/netfilter/nf_tables_api.c:4184:int nft_chain_validate(const struct nft_ctx ctx, struct nft_chain chain)\nnet/netfilter/nf_tables_api.c-4185-{\n--\nnet/netfilter/nf_tables_api.c=4229=static int nft_table_validate(struct net net, const struct nft_table table)\n--\nnet/netfilter/nf_tables_api.c-4231-\tstruct nft_chain chain;\nnet/netfilter/nf_tables_api.c:4232:\tstruct nft_ctx ctx = {\nnet/netfilter/nf_tables_api.c-4233-\t\t.net\t= net,\n--\nnet/netfilter/nf_tables_api.c-4255-\nnet/netfilter/nf_tables_api.c:4256:int nft_setelem_validate(const struct nft_ctx ctx, struct nft_set set,\nnet/netfilter/nf_tables_api.c-4257-\t\t\t const struct nft_set_iter iter,\n--\nnet/netfilter/nf_tables_api.c-4260-\tconst struct nft_set_ext ext = nft_set_elem_ext(set, elem_priv);\nnet/netfilter/nf_tables_api.c:4261:\tstruct nft_ctx pctx = (struct nft_ctx )ctx;\nnet/netfilter/nf_tables_api.c-4262-\tconst struct nft_data data;\n--\nnet/netfilter/nf_tables_api.c-4288-\nnet/netfilter/nf_tables_api.c:4289:int nft_set_catchall_validate(const struct nft_ctx ctx, struct nft_set set)\nnet/netfilter/nf_tables_api.c-4290-{\n--\nnet/netfilter/nf_tables_api.c=4319=static int nf_tables_newrule(struct sk_buff skb, const struct nfnl_info info,\n--\nnet/netfilter/nf_tables_api.c-4336-\tstruct nft_expr expr;\nnet/netfilter/nf_tables_api.c:4337:\tstruct nft_ctx ctx;\nnet/netfilter/nf_tables_api.c-4338-\tstruct nlattr tmp;\n--\nnet/netfilter/nf_tables_api.c-4409-\nnet/netfilter/nf_tables_api.c:4410:\tnft_ctx_init(\u0026ctx, net, skb, info-\u003enlh, family, table, chain, nla);\nnet/netfilter/nf_tables_api.c-4411-\n--\nnet/netfilter/nf_tables_api.c=4574=static int nf_tables_delrule(struct sk_buff skb, const struct nfnl_info info,\n--\nnet/netfilter/nf_tables_api.c-4583-\tstruct nft_rule rule;\nnet/netfilter/nf_tables_api.c:4584:\tstruct nft_ctx ctx;\nnet/netfilter/nf_tables_api.c-4585-\tint err = 0;\n--\nnet/netfilter/nf_tables_api.c-4608-\nnet/netfilter/nf_tables_api.c:4609:\tnft_ctx_init(\u0026ctx, net, skb, info-\u003enlh, family, table, chain, nla);\nnet/netfilter/nf_tables_api.c-4610-\n--\nnet/netfilter/nf_tables_api.c=4681=static const struct nft_set_ops \nnet/netfilter/nf_tables_api.c:4682:nft_select_set_ops(const struct nft_ctx ctx, u32 flags,\nnet/netfilter/nf_tables_api.c-4683-\t\t const struct nft_set_desc desc)\n--\nnet/netfilter/nf_tables_api.c=4836=struct nft_set nft_set_lookup_global(const struct net net,\n--\nnet/netfilter/nf_tables_api.c-4853-\nnet/netfilter/nf_tables_api.c:4854:static int nf_tables_set_alloc_name(struct nft_ctx ctx, struct nft_set set,\nnet/netfilter/nf_tables_api.c-4855-\t\t\t\t const char name)\n--\nnet/netfilter/nf_tables_api.c=4967=nf_tables_fill_set_info(struct sk_buff skb, const struct nft_set set)\n--\nnet/netfilter/nf_tables_api.c-4986-\nnet/netfilter/nf_tables_api.c:4987:static int nf_tables_fill_set(struct sk_buff skb, const struct nft_ctx ctx,\nnet/netfilter/nf_tables_api.c-4988-\t\t\t const struct nft_set set, u16 event, u16 flags)\n--\nnet/netfilter/nf_tables_api.c-5098-\nnet/netfilter/nf_tables_api.c:5099:static void nf_tables_set_notify(const struct nft_ctx ctx,\nnet/netfilter/nf_tables_api.c-5100-\t\t\t\t const struct nft_set set, int event,\n--\nnet/netfilter/nf_tables_api.c=5132=static int nf_tables_dump_sets(struct sk_buff skb, struct netlink_callback cb)\n--\nnet/netfilter/nf_tables_api.c-5137-\tstruct net net = sock_net(skb-\u003esk);\nnet/netfilter/nf_tables_api.c:5138:\tstruct nft_ctx ctx = cb-\u003edata, ctx_set;\nnet/netfilter/nf_tables_api.c-5139-\tstruct nftables_pernet nft_net;\n--\nnet/netfilter/nf_tables_api.c=5193=static int nf_tables_dump_sets_start(struct netlink_callback cb)\nnet/netfilter/nf_tables_api.c-5194-{\nnet/netfilter/nf_tables_api.c:5195:\tstruct nft_ctx ctx_dump = NULL;\nnet/netfilter/nf_tables_api.c-5196-\n--\nnet/netfilter/nf_tables_api.c=5212=static int nf_tables_getset(struct sk_buff skb, const struct nfnl_info info,\n--\nnet/netfilter/nf_tables_api.c-5221-\tstruct sk_buff skb2;\nnet/netfilter/nf_tables_api.c:5222:\tstruct nft_ctx ctx;\nnet/netfilter/nf_tables_api.c-5223-\tint err;\n--\nnet/netfilter/nf_tables_api.c-5233-\nnet/netfilter/nf_tables_api.c:5234:\tnft_ctx_init(\u0026ctx, net, skb, info-\u003enlh, family, table, NULL, nla);\nnet/netfilter/nf_tables_api.c-5235-\n--\nnet/netfilter/nf_tables_api.c=5331=static int nf_tables_set_desc_parse(struct nft_set_desc desc,\n--\nnet/netfilter/nf_tables_api.c-5349-\nnet/netfilter/nf_tables_api.c:5350:static int nft_set_expr_alloc(struct nft_ctx ctx, struct nft_set set,\nnet/netfilter/nf_tables_api.c-5351-\t\t\t const struct nlattr const nla,\n--\nnet/netfilter/nf_tables_api.c=5440=static int nf_tables_newset(struct sk_buff skb, const struct nfnl_info info,\n--\nnet/netfilter/nf_tables_api.c-5451-\tstruct nft_set set;\nnet/netfilter/nf_tables_api.c:5452:\tstruct nft_ctx ctx;\nnet/netfilter/nf_tables_api.c-5453-\tsize_t alloc_size;\n--\nnet/netfilter/nf_tables_api.c-5596-\nnet/netfilter/nf_tables_api.c:5597:\tnft_ctx_init(\u0026ctx, net, skb, info-\u003enlh, family, table, NULL, nla);\nnet/netfilter/nf_tables_api.c-5598-\n--\nnet/netfilter/nf_tables_api.c-5744-\nnet/netfilter/nf_tables_api.c:5745:static void nft_set_catchall_destroy(const struct nft_ctx ctx,\nnet/netfilter/nf_tables_api.c-5746-\t\t\t\t struct nft_set set)\n--\nnet/netfilter/nf_tables_api.c=5757=static void nft_set_put(struct nft_set set)\n--\nnet/netfilter/nf_tables_api.c-5764-\nnet/netfilter/nf_tables_api.c:5765:static void nft_set_destroy(const struct nft_ctx ctx, struct nft_set set)\nnet/netfilter/nf_tables_api.c-5766-{\n--\nnet/netfilter/nf_tables_api.c=5780=static int nf_tables_delset(struct sk_buff skb, const struct nfnl_info info,\n--\nnet/netfilter/nf_tables_api.c-5789-\tstruct nft_set set;\nnet/netfilter/nf_tables_api.c:5790:\tstruct nft_ctx ctx;\nnet/netfilter/nf_tables_api.c-5791-\n--\nnet/netfilter/nf_tables_api.c-5824-\nnet/netfilter/nf_tables_api.c:5825:\tnft_ctx_init(\u0026ctx, net, skb, info-\u003enlh, family, table, NULL, nla);\nnet/netfilter/nf_tables_api.c-5826-\n--\nnet/netfilter/nf_tables_api.c-5829-\nnet/netfilter/nf_tables_api.c:5830:static int nft_validate_register_store(const struct nft_ctx ctx,\nnet/netfilter/nf_tables_api.c-5831-\t\t\t\t enum nft_registers reg,\n--\nnet/netfilter/nf_tables_api.c-5835-\nnet/netfilter/nf_tables_api.c:5836:static int nft_setelem_data_validate(const struct nft_ctx ctx,\nnet/netfilter/nf_tables_api.c-5837-\t\t\t\t struct nft_set set,\n--\nnet/netfilter/nf_tables_api.c-5849-\nnet/netfilter/nf_tables_api.c:5850:static int nf_tables_bind_check_setelem(const struct nft_ctx ctx,\nnet/netfilter/nf_tables_api.c-5851-\t\t\t\t\tstruct nft_set set,\n--\nnet/netfilter/nf_tables_api.c-5862-\nnet/netfilter/nf_tables_api.c:5863:static int nft_set_catchall_bind_check(const struct nft_ctx ctx,\nnet/netfilter/nf_tables_api.c-5864-\t\t\t\t struct nft_set set)\n--\nnet/netfilter/nf_tables_api.c-5884-\nnet/netfilter/nf_tables_api.c:5885:int nf_tables_bind_set(const struct nft_ctx ctx, struct nft_set set,\nnet/netfilter/nf_tables_api.c-5886-\t\t struct nft_set_binding binding)\n--\nnet/netfilter/nf_tables_api.c-5925-\nnet/netfilter/nf_tables_api.c:5926:static void nf_tables_unbind_set(const struct nft_ctx ctx, struct nft_set set,\nnet/netfilter/nf_tables_api.c-5927-\t\t\t\t struct nft_set_binding binding, bool event)\n--\nnet/netfilter/nf_tables_api.c=5940=static void nft_setelem_data_activate(const struct net net,\n--\nnet/netfilter/nf_tables_api.c-5943-\nnet/netfilter/nf_tables_api.c:5944:static int nft_mapelem_activate(const struct nft_ctx ctx,\nnet/netfilter/nf_tables_api.c-5945-\t\t\t\tstruct nft_set set,\n--\nnet/netfilter/nf_tables_api.c-5960-\nnet/netfilter/nf_tables_api.c:5961:static void nft_map_catchall_activate(const struct nft_ctx ctx,\nnet/netfilter/nf_tables_api.c-5962-\t\t\t\t struct nft_set set)\n--\nnet/netfilter/nf_tables_api.c-5977-\nnet/netfilter/nf_tables_api.c:5978:static void nft_map_activate(const struct nft_ctx ctx, struct nft_set set)\nnet/netfilter/nf_tables_api.c-5979-{\n--\nnet/netfilter/nf_tables_api.c-5991-\nnet/netfilter/nf_tables_api.c:5992:void nf_tables_activate_set(const struct nft_ctx ctx, struct nft_set set)\nnet/netfilter/nf_tables_api.c-5993-{\n--\nnet/netfilter/nf_tables_api.c-6003-\nnet/netfilter/nf_tables_api.c:6004:void nf_tables_deactivate_set(const struct nft_ctx ctx, struct nft_set set,\nnet/netfilter/nf_tables_api.c-6005-\t\t\t struct nft_set_binding binding,\n--\nnet/netfilter/nf_tables_api.c-6042-\nnet/netfilter/nf_tables_api.c:6043:void nf_tables_destroy_set(const struct nft_ctx ctx, struct nft_set set)\nnet/netfilter/nf_tables_api.c-6044-{\n--\nnet/netfilter/nf_tables_api.c=6234=struct nft_set_dump_args {\n--\nnet/netfilter/nf_tables_api.c-6240-\nnet/netfilter/nf_tables_api.c:6241:static int nf_tables_dump_setelem(const struct nft_ctx ctx,\nnet/netfilter/nf_tables_api.c-6242-\t\t\t\t struct nft_set set,\n--\nnet/netfilter/nf_tables_api.c=6270=struct nft_set_dump_ctx {\nnet/netfilter/nf_tables_api.c-6271-\tconst struct nft_set\tset;\nnet/netfilter/nf_tables_api.c:6272:\tstruct nft_ctx\t\tctx;\nnet/netfilter/nf_tables_api.c-6273-\tbool\t\t\treset;\n--\nnet/netfilter/nf_tables_api.c=6410=static int nf_tables_fill_setelem_info(struct sk_buff skb,\nnet/netfilter/nf_tables_api.c:6411:\t\t\t\t const struct nft_ctx ctx, u32 seq,\nnet/netfilter/nf_tables_api.c-6412-\t\t\t\t u32 portid, int event, u16 flags,\n--\nnet/netfilter/nf_tables_api.c=6450=static int nft_setelem_parse_flags(const struct nft_set set,\n--\nnet/netfilter/nf_tables_api.c-6468-\nnet/netfilter/nf_tables_api.c:6469:static int nft_setelem_parse_key(struct nft_ctx ctx, const struct nft_set set,\nnet/netfilter/nf_tables_api.c-6470-\t\t\t\t struct nft_data key, struct nlattr attr)\n--\nnet/netfilter/nf_tables_api.c-6480-\nnet/netfilter/nf_tables_api.c:6481:static int nft_setelem_parse_data(struct nft_ctx ctx, struct nft_set set,\nnet/netfilter/nf_tables_api.c-6482-\t\t\t\t struct nft_data_desc desc,\n--\nnet/netfilter/nf_tables_api.c=6501=static void nft_setelem_catchall_get(const struct net net,\n--\nnet/netfilter/nf_tables_api.c-6521-\nnet/netfilter/nf_tables_api.c:6522:static int nft_setelem_get(struct nft_ctx ctx, const struct nft_set set,\nnet/netfilter/nf_tables_api.c-6523-\t\t\t struct nft_set_elem elem, u32 flags)\n--\nnet/netfilter/nf_tables_api.c-6540-\nnet/netfilter/nf_tables_api.c:6541:static int nft_get_set_elem(struct nft_ctx ctx, const struct nft_set set,\nnet/netfilter/nf_tables_api.c-6542-\t\t\t const struct nlattr attr, bool reset)\n--\nnet/netfilter/nf_tables_api.c=6601=static int nft_set_dump_ctx_init(struct nft_set_dump_ctx dump_ctx,\n--\nnet/netfilter/nf_tables_api.c-6626-\nnet/netfilter/nf_tables_api.c:6627:\tnft_ctx_init(\u0026dump_ctx-\u003ectx, net, skb,\nnet/netfilter/nf_tables_api.c-6628-\t\t info-\u003enlh, family, table, NULL, nla);\n--\nnet/netfilter/nf_tables_api.c=6635=static int nf_tables_getsetelem(struct sk_buff skb,\n--\nnet/netfilter/nf_tables_api.c-6686-\nnet/netfilter/nf_tables_api.c:6687:static void nf_tables_setelem_notify(const struct nft_ctx ctx,\nnet/netfilter/nf_tables_api.c-6688-\t\t\t\t const struct nft_set set,\n--\nnet/netfilter/nf_tables_api.c-6722-\nnet/netfilter/nf_tables_api.c:6723:static struct nft_trans nft_trans_elem_alloc(const struct nft_ctx ctx,\n\n" }
11/2	2026/09/20 21:57	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 24467 output: 29 thoughts: 16 Thoughts: Okay, here's my interpretation of those thoughts, summarized in the first person, assuming an expert-level understanding: Diving into Kconfig: NFTables Connection Tracking Right, let's get down to brass tacks. I need to refresh my memory, or maybe even dig into some new aspects, of the Kconfig options for `NFT_CT` (NFTables connection tracking) and `NF_CONNTRACK` (Netfilter connection tracking). Seems like I might be looking at some integration or compatibility issues, or perhaps I'm trying to optimize a configuration. It's time to navigate those menus, understand the dependencies, and see what the build system is allowing or disallowing in relation to these crucial networking components. My goal is to understand how these modules are configured and how they work in conjunction.
12/2	2026/09/20 21:57	tool	grepper	0m Args: { "Expression": "config NFT_CT", "PathPrefix": "net/netfilter/" } Results: { "Output": "net/netfilter/Kconfig=485=config NFT_NUMGEN\n--\nnet/netfilter/Kconfig-490-\nnet/netfilter/Kconfig:491:config NFT_CT\nnet/netfilter/Kconfig-492-\tdepends on NF_CONNTRACK\n" }
13/2	2026/09/20 21:57	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 24764 output: 35 thoughts: 21 Thoughts: Here's my summary, as though I'm reading and processing the provided information: Analyzing `net/netfilter/Kconfig` - Line 490 Area Okay, I'm diving into the `net/netfilter/Kconfig` file. I'm focusing specifically on the lines around line 490. That area usually holds information about… what? Based on the typical Kconfig structure, it's likely defining a configuration option, or perhaps a section heading related to Netfilter, which, as we know, is the Linux kernel's packet filtering framework. I need to understand what's being configured or described there, the dependencies, and the default settings. It's likely related to either a specific module, feature, or subsystem within Netfilter. I'll be looking for keywords like "config," "tristate," "bool," "depends on," "default," and any help text that might shed light on its function. My immediate goal is to understand the context of that specific section. Depending on the specifics, I'll assess its significance, potential implications, and whether any changes would be relevant given my specific understanding of the surrounding Netfilter architecture.
14/2	2026/09/20 21:57	tool	read-file	0m Args: { "File": "net/netfilter/Kconfig", "FirstLine": 488, "LineCount": 25 } Results: { "Contents": " 488:\t\t This option adds the number generator expression used to perform\n 489:\t\t incremental counting and random numbers bound to a upper limit.\n 490:\t\n 491:\tconfig NFT_CT\n 492:\t\tdepends on NF_CONNTRACK\n 493:\t\ttristate \"Netfilter nf_tables conntrack module\"\n 494:\t\thelp\n 495:\t\t This option adds the \"ct\" expression that you can use to match\n 496:\t\t connection tracking information such as the flow state.\n 497:\t\n 498:\tconfig NFT_EXTHDR_DCCP\n 499:\t\tbool \"Netfilter nf_tables exthdr DCCP support (DEPRECATED)\"\n 500:\t\tdefault n\n 501:\t\thelp\n 502:\t\t This option adds support for matching on DCCP extension headers.\n 503:\t\n 504:\tconfig NFT_FLOW_OFFLOAD\n 505:\t\tdepends on NF_CONNTRACK \u0026\u0026 NF_FLOW_TABLE\n 506:\t\ttristate \"Netfilter nf_tables hardware flow offload module\"\n 507:\t\thelp\n 508:\t\t This option adds the \"flow_offload\" expression that you can use to\n 509:\t\t choose what flows are placed into the hardware.\n 510:\t\n 511:\tconfig NFT_CONNLIMIT\n 512:\t\ttristate \"Netfilter nf_tables connlimit module\"\n" }
15/2	2026/09/20 21:57	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 25454 output: 49 thoughts: 54 Thoughts: Okay, let's see, I need to get a handle on how these conntrack modules are built. My intuition says to look at the `netfilter` Makefile, but I need to be more specific. I want to know exactly what's responsible for generating `nf_conntrack_proto.o`, `nf_conntrack_core.o`, and `nf_conntrack_ovs.o`. I'll start with the Makefile in `net/netfilter/` directory and see what I can find. That's the most likely place to start, and should give me the build dependencies or rules.
16/2	2026/09/20 21:57	tool	grepper	0m Args: { "Expression": "nf_conntrack_proto\|nf_conntrack_core\|nf_conntrack_ovs", "PathPrefix": "net/netfilter/" } Results: { "Output": "net/netfilter/Makefile=3=netfilter-$(CONFIG_NETFILTER_NETLINK) += nfnetlink.o\nnet/netfilter/Makefile-4-\nnet/netfilter/Makefile:5:nf_conntrack-y\t:= nf_conntrack_core.o nf_conntrack_standalone.o nf_conntrack_expect.o nf_conntrack_helper.o \\\nnet/netfilter/Makefile:6:\t\t nf_conntrack_proto.o nf_conntrack_proto_generic.o nf_conntrack_proto_tcp.o nf_conntrack_proto_udp.o \\\nnet/netfilter/Makefile:7:\t\t nf_conntrack_proto_icmp.o \\\nnet/netfilter/Makefile-8-\t\t nf_conntrack_extend.o nf_conntrack_acct.o nf_conntrack_seqadj.o\nnet/netfilter/Makefile-9-\nnet/netfilter/Makefile:10:nf_conntrack-$(subst m,y,$(CONFIG_IPV6)) += nf_conntrack_proto_icmpv6.o\nnet/netfilter/Makefile-11-nf_conntrack-$(CONFIG_NF_CONNTRACK_TIMEOUT) += nf_conntrack_timeout.o\n--\nnet/netfilter/Makefile=14=nf_conntrack-$(CONFIG_NF_CONNTRACK_LABELS) += nf_conntrack_labels.o\nnet/netfilter/Makefile:15:nf_conntrack-$(CONFIG_NF_CONNTRACK_OVS) += nf_conntrack_ovs.o\nnet/netfilter/Makefile:16:nf_conntrack-$(CONFIG_NF_CT_PROTO_SCTP) += nf_conntrack_proto_sctp.o\nnet/netfilter/Makefile:17:nf_conntrack-$(CONFIG_NF_CT_PROTO_GRE) += nf_conntrack_proto_gre.o\nnet/netfilter/Makefile-18-ifeq ($(CONFIG_NF_CONNTRACK),m)\n--\nnet/netfilter/ipvs/ip_vs_nfct.c-45-#include \u003cnet/ip_vs.h\u003e\nnet/netfilter/ipvs/ip_vs_nfct.c:46:#include \u003cnet/netfilter/nf_conntrack_core.h\u003e\nnet/netfilter/ipvs/ip_vs_nfct.c-47-#include \u003cnet/netfilter/nf_conntrack_expect.h\u003e\n--\nnet/netfilter/nf_conncount.c-30-#include \u003cnet/netfilter/nf_conntrack_count.h\u003e\nnet/netfilter/nf_conncount.c:31:#include \u003cnet/netfilter/nf_conntrack_core.h\u003e\nnet/netfilter/nf_conncount.c-32-#include \u003cnet/netfilter/nf_conntrack_tuple.h\u003e\n--\nnet/netfilter/nf_conntrack_bpf.c-19-#include \u003cnet/netfilter/nf_conntrack_bpf.h\u003e\nnet/netfilter/nf_conntrack_bpf.c:20:#include \u003cnet/netfilter/nf_conntrack_core.h\u003e\nnet/netfilter/nf_conntrack_bpf.c-21-\n--\nnet/netfilter/nf_conntrack_core.c-40-#include \u003cnet/netfilter/nf_conntrack_helper.h\u003e\nnet/netfilter/nf_conntrack_core.c:41:#include \u003cnet/netfilter/nf_conntrack_core.h\u003e\nnet/netfilter/nf_conntrack_core.c-42-#include \u003cnet/netfilter/nf_conntrack_extend.h\u003e\n--\nnet/netfilter/nf_conntrack_core.c=2552=void nf_conntrack_cleanup_end(void)\n--\nnet/netfilter/nf_conntrack_core.c-2557-\nnet/netfilter/nf_conntrack_core.c:2558:\tnf_conntrack_proto_fini();\nnet/netfilter/nf_conntrack_core.c-2559-\tnf_conntrack_helper_fini();\n--\nnet/netfilter/nf_conntrack_core.c=2722=int nf_conntrack_init_start(void)\n--\nnet/netfilter/nf_conntrack_core.c-2776-\nnet/netfilter/nf_conntrack_core.c:2777:\tret = nf_conntrack_proto_init();\nnet/netfilter/nf_conntrack_core.c-2778-\tif (ret \u003c 0)\n--\nnet/netfilter/nf_conntrack_core.c-2791-\tcancel_delayed_work_sync(\u0026conntrack_gc_work.dwork);\nnet/netfilter/nf_conntrack_core.c:2792:\tnf_conntrack_proto_fini();\nnet/netfilter/nf_conntrack_core.c-2793-err_proto:\n--\nnet/netfilter/nf_conntrack_core.c=2835=int nf_conntrack_init_net(struct net net)\n--\nnet/netfilter/nf_conntrack_core.c-2854-\tnf_conntrack_ecache_pernet_init(net);\nnet/netfilter/nf_conntrack_core.c:2855:\tnf_conntrack_proto_pernet_init(net);\nnet/netfilter/nf_conntrack_core.c-2856-\n--\nnet/netfilter/nf_conntrack_ecache.c-24-#include \u003cnet/netfilter/nf_conntrack.h\u003e\nnet/netfilter/nf_conntrack_ecache.c:25:#include \u003cnet/netfilter/nf_conntrack_core.h\u003e\nnet/netfilter/nf_conntrack_ecache.c-26-#include \u003cnet/netfilter/nf_conntrack_ecache.h\u003e\n--\nnet/netfilter/nf_conntrack_expect.c-26-#include \u003cnet/netfilter/nf_conntrack.h\u003e\nnet/netfilter/nf_conntrack_expect.c:27:#include \u003cnet/netfilter/nf_conntrack_core.h\u003e\nnet/netfilter/nf_conntrack_expect.c-28-#include \u003cnet/netfilter/nf_conntrack_ecache.h\u003e\n--\nnet/netfilter/nf_conntrack_h323_main.c-29-#include \u003cnet/netfilter/nf_conntrack.h\u003e\nnet/netfilter/nf_conntrack_h323_main.c:30:#include \u003cnet/netfilter/nf_conntrack_core.h\u003e\nnet/netfilter/nf_conntrack_h323_main.c-31-#include \u003cnet/netfilter/nf_conntrack_tuple.h\u003e\n--\nnet/netfilter/nf_conntrack_helper.c-23-#include \u003cnet/netfilter/nf_conntrack.h\u003e\nnet/netfilter/nf_conntrack_helper.c:24:#include \u003cnet/netfilter/nf_conntrack_core.h\u003e\nnet/netfilter/nf_conntrack_helper.c-25-#include \u003cnet/netfilter/nf_conntrack_ecache.h\u003e\n--\nnet/netfilter/nf_conntrack_netlink.c-36-#include \u003cnet/netfilter/nf_conntrack.h\u003e\nnet/netfilter/nf_conntrack_netlink.c:37:#include \u003cnet/netfilter/nf_conntrack_core.h\u003e\nnet/netfilter/nf_conntrack_netlink.c-38-#include \u003cnet/netfilter/nf_conntrack_expect.h\u003e\n--\nnet/netfilter/nf_conntrack_pptp.c-31-#include \u003cnet/netfilter/nf_conntrack.h\u003e\nnet/netfilter/nf_conntrack_pptp.c:32:#include \u003cnet/netfilter/nf_conntrack_core.h\u003e\nnet/netfilter/nf_conntrack_pptp.c-33-#include \u003cnet/netfilter/nf_conntrack_helper.h\u003e\nnet/netfilter/nf_conntrack_pptp.c-34-#include \u003cnet/netfilter/nf_conntrack_zones.h\u003e\nnet/netfilter/nf_conntrack_pptp.c:35:#include \u003clinux/netfilter/nf_conntrack_proto_gre.h\u003e\nnet/netfilter/nf_conntrack_pptp.c-36-#include \u003clinux/netfilter/nf_conntrack_pptp.h\u003e\n--\nnet/netfilter/nf_conntrack_proto.c-17-#include \u003cnet/netfilter/nf_conntrack_l4proto.h\u003e\nnet/netfilter/nf_conntrack_proto.c:18:#include \u003cnet/netfilter/nf_conntrack_core.h\u003e\nnet/netfilter/nf_conntrack_proto.c-19-#include \u003cnet/netfilter/nf_conntrack_bridge.h\u003e\n--\nnet/netfilter/nf_conntrack_proto.c=752=EXPORT_SYMBOL_GPL(nf_ct_bridge_unregister);\nnet/netfilter/nf_conntrack_proto.c-753-\nnet/netfilter/nf_conntrack_proto.c:754:int nf_conntrack_proto_init(void)\nnet/netfilter/nf_conntrack_proto.c-755-{\n--\nnet/netfilter/nf_conntrack_proto.c-776-\nnet/netfilter/nf_conntrack_proto.c:777:void nf_conntrack_proto_fini(void)\nnet/netfilter/nf_conntrack_proto.c-778-{\n--\nnet/netfilter/nf_conntrack_proto.c-784-\nnet/netfilter/nf_conntrack_proto.c:785:void nf_conntrack_proto_pernet_init(struct net net)\nnet/netfilter/nf_conntrack_proto.c-786-{\n--\nnet/netfilter/nf_conntrack_proto_gre.c-40-#include \u003cnet/netfilter/nf_conntrack_helper.h\u003e\nnet/netfilter/nf_conntrack_proto_gre.c:41:#include \u003cnet/netfilter/nf_conntrack_core.h\u003e\nnet/netfilter/nf_conntrack_proto_gre.c-42-#include \u003cnet/netfilter/nf_conntrack_timeout.h\u003e\nnet/netfilter/nf_conntrack_proto_gre.c-43-#include \u003cnet/pptp.h\u003e\nnet/netfilter/nf_conntrack_proto_gre.c:44:#include \u003clinux/netfilter/nf_conntrack_proto_gre.h\u003e\nnet/netfilter/nf_conntrack_proto_gre.c-45-#include \u003clinux/netfilter/nf_conntrack_pptp.h\u003e\n--\nnet/netfilter/nf_conntrack_proto_gre.c=215=bool gre_pkt_to_tuple(const struct sk_buff skb, unsigned int dataoff,\n--\nnet/netfilter/nf_conntrack_proto_gre.c-226-\tif (!grehdr \|\| (grehdr-\u003eflags \u0026 GRE_VERSION) != GRE_VERSION_1) {\nnet/netfilter/nf_conntrack_proto_gre.c:227:\t\t/ try to behave like \"nf_conntrack_proto_generic\" /\nnet/netfilter/nf_conntrack_proto_gre.c-228-\t\ttuple-\u003esrc.u.all = 0;\n--\nnet/netfilter/nf_conntrack_proto_icmp.c-17-#include \u003cnet/netfilter/nf_conntrack_l4proto.h\u003e\nnet/netfilter/nf_conntrack_proto_icmp.c:18:#include \u003cnet/netfilter/nf_conntrack_core.h\u003e\nnet/netfilter/nf_conntrack_proto_icmp.c-19-#include \u003cnet/netfilter/nf_conntrack_timeout.h\u003e\n--\nnet/netfilter/nf_conntrack_proto_icmp.c=204=int nf_conntrack_icmpv4_error(struct nf_conn tmpl,\n--\nnet/netfilter/nf_conntrack_proto_icmp.c-218-\nnet/netfilter/nf_conntrack_proto_icmp.c:219:\t/* See nf_conntrack_proto_tcp.c */\nnet/netfilter/nf_conntrack_proto_icmp.c-220-\tif (state-\u003enet-\u003ect.sysctl_checksum \u0026\u0026\n--\nnet/netfilter/nf_conntrack_proto_icmpv6.c-21-#include \u003cnet/netfilter/nf_conntrack_l4proto.h\u003e\nnet/netfilter/nf_conntrack_proto_icmpv6.c:22:#include \u003cnet/netfilter/nf_conntrack_core.h\u003e\nnet/netfilter/nf_conntrack_proto_icmpv6.c-23-#include \u003cnet/netfilter/nf_conntrack_timeout.h\u003e\n--\nnet/netfilter/nf_conntrack_sip.c-23-#include \u003cnet/netfilter/nf_conntrack.h\u003e\nnet/netfilter/nf_conntrack_sip.c:24:#include \u003cnet/netfilter/nf_conntrack_core.h\u003e\nnet/netfilter/nf_conntrack_sip.c-25-#include \u003cnet/netfilter/nf_conntrack_expect.h\u003e\n--\nnet/netfilter/nf_conntrack_standalone.c-18-#include \u003cnet/netfilter/nf_conntrack.h\u003e\nnet/netfilter/nf_conntrack_standalone.c:19:#include \u003cnet/netfilter/nf_conntrack_core.h\u003e\nnet/netfilter/nf_conntrack_standalone.c-20-#include \u003cnet/netfilter/nf_conntrack_l4proto.h\u003e\n--\nnet/netfilter/nf_conntrack_timeout.c-19-#include \u003cnet/netfilter/nf_conntrack.h\u003e\nnet/netfilter/nf_conntrack_timeout.c:20:#include \u003cnet/netfilter/nf_conntrack_core.h\u003e\nnet/netfilter/nf_conntrack_timeout.c-21-#include \u003cnet/netfilter/nf_conntrack_extend.h\u003e\n--\nnet/netfilter/nf_flow_table_core.c-12-#include \u003cnet/netfilter/nf_conntrack.h\u003e\nnet/netfilter/nf_flow_table_core.c:13:#include \u003cnet/netfilter/nf_conntrack_core.h\u003e\nnet/netfilter/nf_flow_table_core.c-14-#include \u003cnet/netfilter/nf_conntrack_l4proto.h\u003e\n--\nnet/netfilter/nf_flow_table_offload.c-14-#include \u003cnet/netfilter/nf_conntrack_acct.h\u003e\nnet/netfilter/nf_flow_table_offload.c:15:#include \u003cnet/netfilter/nf_conntrack_core.h\u003e\nnet/netfilter/nf_flow_table_offload.c-16-#include \u003cnet/netfilter/nf_conntrack_tuple.h\u003e\n--\nnet/netfilter/nf_flow_table_path.c-14-#include \u003cnet/netfilter/nf_tables_core.h\u003e\nnet/netfilter/nf_flow_table_path.c:15:#include \u003cnet/netfilter/nf_conntrack_core.h\u003e\nnet/netfilter/nf_flow_table_path.c-16-#include \u003cnet/netfilter/nf_conntrack_extend.h\u003e\n--\nnet/netfilter/nf_nat_bpf.c-11-#include \u003cnet/netfilter/nf_conntrack_bpf.h\u003e\nnet/netfilter/nf_nat_bpf.c:12:#include \u003cnet/netfilter/nf_conntrack_core.h\u003e\nnet/netfilter/nf_nat_bpf.c-13-#include \u003cnet/netfilter/nf_nat.h\u003e\n--\nnet/netfilter/nf_nat_core.c-19-#include \u003cnet/netfilter/nf_conntrack_bpf.h\u003e\nnet/netfilter/nf_nat_core.c:20:#include \u003cnet/netfilter/nf_conntrack_core.h\u003e\nnet/netfilter/nf_nat_core.c-21-#include \u003cnet/netfilter/nf_conntrack_helper.h\u003e\n--\nnet/netfilter/nf_nat_proto.c-29-\nnet/netfilter/nf_nat_proto.c:30:#include \u003cnet/netfilter/nf_conntrack_core.h\u003e\nnet/netfilter/nf_nat_proto.c-31-#include \u003cnet/netfilter/nf_conntrack.h\u003e\n--\nnet/netfilter/nf_nat_sip.c-17-#include \u003cnet/netfilter/nf_nat_helper.h\u003e\nnet/netfilter/nf_nat_sip.c:18:#include \u003cnet/netfilter/nf_conntrack_core.h\u003e\nnet/netfilter/nf_nat_sip.c-19-#include \u003cnet/netfilter/nf_conntrack_helper.h\u003e\n--\nnet/netfilter/nfnetlink_cttimeout.c-25-#include \u003cnet/netfilter/nf_conntrack.h\u003e\nnet/netfilter/nfnetlink_cttimeout.c:26:#include \u003cnet/netfilter/nf_conntrack_core.h\u003e\nnet/netfilter/nfnetlink_cttimeout.c-27-#include \u003cnet/netfilter/nf_conntrack_l4proto.h\u003e\n--\nnet/netfilter/nft_connlimit.c-11-#include \u003cnet/netfilter/nf_conntrack_count.h\u003e\nnet/netfilter/nft_connlimit.c:12:#include \u003cnet/netfilter/nf_conntrack_core.h\u003e\nnet/netfilter/nft_connlimit.c-13-#include \u003cnet/netfilter/nf_conntrack_tuple.h\u003e\n--\nnet/netfilter/nft_flow_offload.c-15-#include \u003cnet/netfilter/nf_tables_core.h\u003e\nnet/netfilter/nft_flow_offload.c:16:#include \u003cnet/netfilter/nf_conntrack_core.h\u003e\nnet/netfilter/nft_flow_offload.c-17-#include \u003cnet/netfilter/nf_conntrack_extend.h\u003e\n--\nnet/netfilter/xt_connlimit.c-24-#include \u003cnet/netfilter/nf_conntrack.h\u003e\nnet/netfilter/xt_connlimit.c:25:#include \u003cnet/netfilter/nf_conntrack_core.h\u003e\nnet/netfilter/xt_connlimit.c-26-#include \u003cnet/netfilter/nf_conntrack_tuple.h\u003e\n--\nnet/netfilter/xt_helper.c-10-#include \u003cnet/netfilter/nf_conntrack.h\u003e\nnet/netfilter/xt_helper.c:11:#include \u003cnet/netfilter/nf_conntrack_core.h\u003e\nnet/netfilter/xt_helper.c-12-#include \u003cnet/netfilter/nf_conntrack_helper.h\u003e\n" }
17/2	2026/09/20 21:57	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 30599 output: 30 thoughts: 148 Thoughts: Analyzing the nf_conntrack Build Process Okay, so I'm looking at this build configuration. It seems like `nf_conntrack-y` is defined as a collection of object files: `nf_conntrack_core.o`, `nf_conntrack_standalone.o`, and so on. That makes sense; it's the core module. Also, `obj-$(CONFIG_NF_CONNTRACK) += nf_conntrack.o`. This tells me that if `CONFIG_NF_CONNTRACK` is enabled, then `nf_conntrack.o` is included in the build. We also have `obj-$(CONFIG_NFT_CT) += nft_ct.o`, so if the `NFT_CT` config is enabled, it includes `nft_ct.o`. Now, things are getting interesting... `nf_conntrack-$(CONFIG_NF_CONNTRACK_OVS) += nf_conntrack_ovs.o`. Ah, this is where it ties into Open vSwitch. I need to check the Kconfig definition of `CONFIG_NF_CONNTRACK_OVS` to fully understand the dependencies and how this module integrates with the Open vSwitch-specific features. Let's see how that's defined in the configuration files.
18/2	2026/09/20 21:57	tool	grepper	0m Args: { "Expression": "config NF_CONNTRACK_OVS", "PathPrefix": "net/" } Results: { "Output": "net/netfilter/Kconfig=188=config NF_CONNTRACK_LABELS\n--\nnet/netfilter/Kconfig-194-\nnet/netfilter/Kconfig:195:config NF_CONNTRACK_OVS\nnet/netfilter/Kconfig-196-\tbool\n" }
19/2	2026/09/20 21:57	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 31142 output: 21 thoughts: 15 Thoughts: Okay, here's my interpretation of that thought process, tailored for an expert audience, and written in the first person: Analyzing the Selection of `NF_CONNTRACK_OVS` Alright, so the question is, who's choosing to activate `NF_CONNTRACK_OVS`? That's the real crux of this. We're looking at a specific instantiation of connection tracking, likely within an Open vSwitch environment. My initial thought process here is to determine why it's being selected and what the implications are. I immediately start mentally cataloging the likely candidates: * Networking Stack Configuration: Is this being explicitly enabled in the kernel config? Is it part of a default set of modules that's loaded by the chosen distribution? What's the complete configuration? * Open vSwitch Integration: Is OVS specifically configured to use conntrack? This suggests something more complex, perhaps leveraging specific features. How are the OVS bridges or tunnels configured? Are they requiring tracking in certain ways? * Containerization/Orchestration: Is this happening within a containerized environment (e.g., Docker, Kubernetes, etc.)? Are they using network policies that rely on connection tracking at the OVS level? Is it an environment where the network is managed programmatically. * Security Policies: Are firewall rules or security policies implemented that depend on connection tracking for stateful inspection? Are they relying on it for things like Network Address Translation (NAT) or other functions? * Performance Considerations: Could someone be experimenting with offloading connection tracking to hardware? Are there any indications that it's being used for a specific performance tuning purpose? * Kernel Version: I'd probably start poking around the kernel configuration files for the system, and checking the system version. Was it selected directly or via dependencies on other components? I'll need to dig deeper into the system's setup to understand the driving force behind this selection. My immediate next steps would be to examine the configuration files, any automation scripts involved, and probably start tracing how this specific module is integrated into the larger networking picture. This requires a systematic approach to uncover the 'why' behind this module selection, as there is a number of possibilities.
20/2	2026/09/20 21:57	tool	grepper	0m Args: { "Expression": "NF_CONNTRACK_OVS" } Results: { "Output": "net/netfilter/Kconfig=188=config NF_CONNTRACK_LABELS\n--\nnet/netfilter/Kconfig-194-\nnet/netfilter/Kconfig:195:config NF_CONNTRACK_OVS\nnet/netfilter/Kconfig-196-\tbool\n--\nnet/netfilter/Makefile=14=nf_conntrack-$(CONFIG_NF_CONNTRACK_LABELS) += nf_conntrack_labels.o\nnet/netfilter/Makefile:15:nf_conntrack-$(CONFIG_NF_CONNTRACK_OVS) += nf_conntrack_ovs.o\nnet/netfilter/Makefile-16-nf_conntrack-$(CONFIG_NF_CT_PROTO_SCTP) += nf_conntrack_proto_sctp.o\n--\nnet/openvswitch/Kconfig=6=config OPENVSWITCH\n--\nnet/openvswitch/Kconfig-18-\tselect NET_NSH\nnet/openvswitch/Kconfig:19:\tselect NF_CONNTRACK_OVS if NF_CONNTRACK\nnet/openvswitch/Kconfig-20-\tselect NF_NAT_OVS if NF_NAT\n--\nnet/sched/Kconfig=917=config NET_ACT_CT\n--\nnet/sched/Kconfig-919-\tdepends on NET_CLS_ACT \u0026\u0026 NF_CONNTRACK \u0026\u0026 (!NF_NAT \|\| NF_NAT) \u0026\u0026 NF_FLOW_TABLE\nnet/sched/Kconfig:920:\tselect NF_CONNTRACK_OVS\nnet/sched/Kconfig-921-\tselect NF_NAT_OVS if NF_NAT\n--\ntools/testing/selftests/net/config=109=CONFIG_NF_CONNTRACK=m\ntools/testing/selftests/net/config:110:CONFIG_NF_CONNTRACK_OVS=y\ntools/testing/selftests/net/config-111-CONFIG_NF_FLOW_TABLE=m\n--\ntools/testing/selftests/net/openvswitch/config=8=CONFIG_NF_CONNTRACK=m\ntools/testing/selftests/net/openvswitch/config:9:CONFIG_NF_CONNTRACK_OVS=y\ntools/testing/selftests/net/openvswitch/config-10-CONFIG_OPENVSWITCH=m\n" }
21/2	2026/09/20 21:57	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 32233 output: 35 thoughts: 138 Thoughts: My Conntrack Configuration Investigation Okay, so `OPENVSWITCH` and `NET_ACT_CT` both rely on `NF_CONNTRACK_OVS`. Right. But then `NFT_CT` – the Netfilter nf_tables conntrack module – needs `NF_CONNTRACK`. Makes sense, of course, as you'd expect conntrack functionality. Now, I should make sure about the dependencies of `NFT_CT` itself. Let's dig into `net/netfilter/Kconfig` and verify its dependencies. Aha! Line 491 of `Kconfig` confirms that `NFT_CT` does depend on `NF_CONNTRACK`. But, hang on... does it also rely on `NF_TABLES`? Let me double-check the Kconfig file for the `NF_TABLES` dependency specifically and confirm.
22/2	2026/09/20 21:57	tool	read-file	0m Args: { "File": "net/netfilter/Kconfig", "FirstLine": 460, "LineCount": 35 } Results: { "Contents": " 460:\t\t nftables is the new packet classification framework that intends to\n 461:\t\t replace the existing {ip,ip6,arp,eb}_tables infrastructure. It\n 462:\t\t provides a pseudo-state machine with an extensible instruction-set\n 463:\t\t (also known as expressions) that the userspace 'nft' utility\n 464:\t\t (https://www.netfilter.org/projects/nftables) uses to build the\n 465:\t\t rule-set. It also comes with the generic set infrastructure that\n 466:\t\t allows you to construct mappings between matchings and actions\n 467:\t\t for performance lookups.\n 468:\t\n 469:\t\t To compile it as a module, choose M here.\n 470:\t\n 471:\tif NF_TABLES\n 472:\tconfig NF_TABLES_INET\n 473:\t\tdepends on IPV6\n 474:\t\tselect NF_TABLES_IPV4\n 475:\t\tselect NF_TABLES_IPV6\n 476:\t\tbool \"Netfilter nf_tables mixed IPv4/IPv6 tables support\"\n 477:\t\thelp\n 478:\t\t This option enables support for a mixed IPv4/IPv6 \"inet\" table.\n 479:\t\n 480:\tconfig NF_TABLES_NETDEV\n 481:\t\tbool \"Netfilter nf_tables netdev tables support\"\n 482:\t\thelp\n 483:\t\t This option enables support for the \"netdev\" table.\n 484:\t\n 485:\tconfig NFT_NUMGEN\n 486:\t\ttristate \"Netfilter nf_tables number generator module\"\n 487:\t\thelp\n 488:\t\t This option adds the number generator expression used to perform\n 489:\t\t incremental counting and random numbers bound to a upper limit.\n 490:\t\n 491:\tconfig NFT_CT\n 492:\t\tdepends on NF_CONNTRACK\n 493:\t\ttristate \"Netfilter nf_tables conntrack module\"\n 494:\t\thelp\n" }
23/2	2026/09/20 21:57	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 33142 output: 59 thoughts: 1036 Thoughts: Analyzing Netfilter Conntrack Changes Okay, so we're dealing with code changes within `if NF_TABLES`, which means `NFT_CT` relies on both `NF_TABLES` and `NF_CONNTRACK`. And of course, `CONFIG_NETFILTER` is the overarching parent config. Now, let's break down the functions added or modified. I've got a list here: 1. `nf_ct_check_icmp_inner`: static in `net/netfilter/nf_conntrack_core.c` 2. `nf_ct_get_careful`: static in `net/netfilter/nf_conntrack_core.c` 3. `nf_conntrack_in`: non-static in `net/netfilter/nf_conntrack_core.c` 4. `nf_ct_helper`: in `net/netfilter/nf_conntrack_ovs.c` 5. `nf_confirm_get_protoff`: static in `net/netfilter/nf_conntrack_proto.c` 6. `nf_ct_call_helper`: non-static in `net/netfilter/nf_conntrack_proto.c` 7. `nf_confirm`: non-static in `net/netfilter/nf_conntrack_proto.c` 8. `nft_ct_get_safe`: static in `net/netfilter/nft_ct.c` 9. `nft_ct_timeout_obj_eval`: in `net/netfilter/nft_ct.c` 10. `nft_ct_helper_obj_eval`: in `net/netfilter/nft_ct.c` 11. `nft_ct_expect_helper_alloc`: in `net/netfilter/nft_ct.c` My initial thought was to quickly check the ubiquity of `nf_conntrack_in` and `nf_confirm`, but wait, hold on. Section 4 from the documentation is flashing a red light. We need to avoid listing overly generic functions that are called everywhere. It'll dilute the fuzzing effort. We want the specific feature logic entrypoints. Okay, so the .c static functions - `nf_ct_get_careful`, `nf_ct_check_icmp_inner`, `nf_confirm_get_protoff`, and `nft_ct_get_safe` - are they actually distinct symbols or inlined? In the kernel vmlinux context, static .c functions might be distinct symbols, it depends on the compiler's inlining. Non-static functions, that's what we want to target for the most part. Now, let's nail this down. `nf_ct_call_helper`? I know that one's declared in `include/net/netfilter/nf_conntrack_helper.h` as `int nf_ct_call_helper(struct sk_buff skb, struct nf_conn ct, enum ip_conntrack_info ctinfo)`. That's non-static! And `nf_confirm` and `nf_ct_helper`, both non-static. But the `nft_ct` ones look like they have ops or are static. We must investigate `nft_ct.c`!
24/2	2026/09/20 21:57	tool	grepper	0m Args: { "Expression": "nft_ct_timeout_obj_eval\|nft_ct_helper_obj_eval\|nft_ct_expect_helper_alloc", "PathPrefix": "net/netfilter/nft_ct.c" } Results: { "Output": "net/netfilter/nft_ct.c=899=struct nft_ct_timeout_obj {\n--\nnet/netfilter/nft_ct.c-903-\nnet/netfilter/nft_ct.c:904:static void nft_ct_timeout_obj_eval(struct nft_object obj,\nnet/netfilter/nft_ct.c-905-\t\t\t\t struct nft_regs regs,\n--\nnet/netfilter/nft_ct.c=1034=static const struct nft_object_ops nft_ct_timeout_obj_ops = {\n--\nnet/netfilter/nft_ct.c-1036-\t.size\t\t= sizeof(struct nft_ct_timeout_obj),\nnet/netfilter/nft_ct.c:1037:\t.eval\t\t= nft_ct_timeout_obj_eval,\nnet/netfilter/nft_ct.c-1038-\t.init\t\t= nft_ct_timeout_obj_init,\n--\nnet/netfilter/nft_ct.c=1125=static void nft_ct_helper_obj_destroy(const struct nft_ctx ctx,\n--\nnet/netfilter/nft_ct.c-1137-\nnet/netfilter/nft_ct.c:1138:static void nft_ct_helper_obj_eval(struct nft_object obj,\nnet/netfilter/nft_ct.c-1139-\t\t\t\t struct nft_regs regs,\n--\nnet/netfilter/nft_ct.c=1217=static const struct nft_object_ops nft_ct_helper_obj_ops = {\n--\nnet/netfilter/nft_ct.c-1219-\t.size\t\t= sizeof(struct nft_ct_helper_obj),\nnet/netfilter/nft_ct.c:1220:\t.eval\t\t= nft_ct_helper_obj_eval,\nnet/netfilter/nft_ct.c-1221-\t.init\t\t= nft_ct_helper_obj_init,\n--\nnet/netfilter/nft_ct.c=1271=static int ct_expect_help(struct sk_buff skb, unsigned int protoff,\n--\nnet/netfilter/nft_ct.c-1319-\nnet/netfilter/nft_ct.c:1320:static int nft_ct_expect_helper_alloc(struct nft_ct_expect_obj priv)\nnet/netfilter/nft_ct.c-1321-{\n--\nnet/netfilter/nft_ct.c=1343=static int nft_ct_expect_obj_init(const struct nft_ctx ctx,\n--\nnet/netfilter/nft_ct.c-1397-\nnet/netfilter/nft_ct.c:1398:\terr = nft_ct_expect_helper_alloc(priv);\nnet/netfilter/nft_ct.c-1399-\tif (err \u003c 0) {\n" }
25/2	2026/09/20 21:57	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 35727 output: 20 thoughts: 28 Thoughts: Here's my attempt at summarizing the thought process, as if I were thinking it: Tracing `nf_ct_helper` Calls in `nf_conntrack_ovs.c` Okay, so I need to understand how the `nf_ct_helper` function is being used within the `nf_conntrack_ovs.c` module. I know this module is related to Open vSwitch and conntrack, so there's probably some interesting interplay going on here. First, let's just get a handle on the function's callers. I need to figure out what functions are directly calling `nf_ct_helper` within that specific file. It could be some custom connection tracking logic OVS is adding or some other helper-related work. I'm hoping to understand the complete picture of its context to see the impact of that function. I'll need to use some tooling, probably `grep` or `cscope` or maybe even just a quick search within the source code directory to identify those direct calls. Let's start with that and then I'll figure out what I'm looking at.
26/2	2026/09/20 21:58	tool	grepper	0m Args: { "Expression": "nf_ct_helper\\(" } Results: { "Output": "include/net/netfilter/nf_conntrack_helper.h=122=int __nf_ct_try_assign_helper(struct nf_conn ct, struct nf_conn tmpl,\n--\ninclude/net/netfilter/nf_conntrack_helper.h-124-\ninclude/net/netfilter/nf_conntrack_helper.h:125:int nf_ct_helper(struct sk_buff skb, struct nf_conn ct,\ninclude/net/netfilter/nf_conntrack_helper.h-126-\t\t enum ip_conntrack_info ctinfo, u16 proto);\n--\nnet/netfilter/nf_conntrack_ovs.c-11-/* 'skb' should already be pulled to nh_ofs. /\nnet/netfilter/nf_conntrack_ovs.c:12:int nf_ct_helper(struct sk_buff skb, struct nf_conn ct,\nnet/netfilter/nf_conntrack_ovs.c-13-\t\t enum ip_conntrack_info ctinfo, u16 proto)\n--\nnet/openvswitch/conntrack.c=724=static int __ovs_ct_lookup(struct net net, struct sw_flow_key key,\n--\nnet/openvswitch/conntrack.c-818-\t\t\t\t\t info-\u003ecommit)) {\nnet/openvswitch/conntrack.c:819:\t\t\tint err = nf_ct_helper(skb, ct, ctinfo, info-\u003efamily);\nnet/openvswitch/conntrack.c-820-\n--\nnet/sched/act_ct.c=979=TC_INDIRECT_SCOPE int tcf_ct_act(struct sk_buff skb, const struct tc_action *a,\n--\nnet/sched/act_ct.c-1093-\tif (nf_ct_is_confirmed(ct) ? ((!cached \u0026\u0026 !skip_add) \|\| add_helper) : commit) {\nnet/sched/act_ct.c:1094:\t\terr = nf_ct_helper(skb, ct, ctinfo, family);\nnet/sched/act_ct.c-1095-\t\tif (err != NF_ACCEPT)\n" }
27/2	2026/09/20 21:58	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 36582 output: 38 thoughts: 1409 Thoughts: Conntrack Integrity and Protocol Validation: A Deep Dive Okay, so I'm looking at how `openvswitch` (`__ovs_ct_lookup`) and `act_ct` (`tcf_ct_act`) hook into `nf_ct_helper`, which itself is called by `nf_ct_call_helper` within `nf_ct_helper` and `nf_confirm`. The core conntrack hook, `nf_conntrack_in`, calls `nf_ct_get_careful`. That raises a question, is `nf_conntrack_in` specific to conntrack or is it a ubiquitous function? Ah, it's the central hook for conntrack within netfilter (`NF_INET_PRE_ROUTING`, `NF_INET_LOCAL_OUT`). It seems specific to conntrack, but it might be invoked for IP packets. Good, then `nf_ct_get_careful` is the crucial point, that's where the new revalidation logic was introduced within `nf_conntrack_core.c`. Let me quickly recap the functions involved: `nf_ct_get_careful`, `nf_ct_check_icmp_inner`, `nf_confirm_get_protoff`, `nf_ct_call_helper`, `nf_confirm`, `nf_ct_helper`, `nft_ct_get_safe`, `nft_ct_timeout_obj_eval`, `nft_ct_helper_obj_eval`, and `nft_ct_expect_helper_alloc`. Now, that `DEBUG_NET_WARN_ONCE` within `nf_confirm_get_protoff` replaced a `WARN_ONCE` in `nf_ct_helper`, that's key. It indicates a potential issue with helpers being invoked on non-IP families. Alright, let's circle back to the patch's context. The comments are pretty clear. The patch series is about handling mangled packets (e.g., modified by TC pedit/clsact, BPF or malformed packets) or mismatched L4 protocols. Specifically scenarios that can lead to conntrack helpers, confirmation or `nft_ct` misinterpreting packet data, leading to problems like out-of-bounds access, incorrect helper parsing, or state corruption. It's really about hardening conntrack's security and integrity. To reach these functions, I need certain configurations. `NF_CONNTRACK` is essential (for building `nf_conntrack_core.c` and `nf_conntrack_proto.c`), `NF_CONNTRACK_OVS` (building `nf_conntrack_ovs.c`, selectable by `OPENVSWITCH` or `NET_ACT_CT`), `NFT_CT` (for `nft_ct.c`), and `NF_TABLES` (a dependency of `NFT_CT`) and of course `NETFILTER`. Interesting, I see that `NF_CONNTRACK_OVS` can only be selected by `OPENVSWITCH` or `NET_ACT_CT`. So, the minimal configurations are, in short: * `NF_CONNTRACK` * `NF_TABLES` * `NFT_CT` * `OPENVSWITCH` * `NET_ACT_CT` I should also check if `NF_CONNTRACK_TIMEOUT` is needed, looking at the code, in `net/netfilter/nft_ct.c` around line 870, `nft_ct_timeout_obj_eval` is included under `#ifdef CONFIG_NF_CONNTRACK_TIMEOUT`. So there's potentially one more configuration.
28/2	2026/09/20 21:58	tool	read-file	0m Args: { "File": "net/netfilter/nft_ct.c", "FirstLine": 865, "LineCount": 45 } Results: { "Contents": " 865:\t\t\treturn NULL;\n 866:\t\n 867:\t\treturn ct;\n 868:\t}\n 869:\t\n 870:\t#ifdef CONFIG_NF_CONNTRACK_TIMEOUT\n 871:\tstatic int\n 872:\tnft_ct_timeout_parse_policy(void timeouts,\n 873:\t\t\t\t const struct nf_conntrack_l4proto l4proto,\n 874:\t\t\t\t struct net net, const struct nlattr attr)\n 875:\t{\n 876:\t\tstruct nlattr *tb;\n 877:\t\tint ret = 0;\n 878:\t\n 879:\t\ttb = kzalloc_objs(tb, l4proto-\u003ectnl_timeout.nlattr_max + 1);\n 880:\t\n 881:\t\tif (!tb)\n 882:\t\t\treturn -ENOMEM;\n 883:\t\n 884:\t\tret = nla_parse_nested_deprecated(tb,\n 885:\t\t\t\t\t\t l4proto-\u003ectnl_timeout.nlattr_max,\n 886:\t\t\t\t\t\t attr,\n 887:\t\t\t\t\t\t l4proto-\u003ectnl_timeout.nla_policy,\n 888:\t\t\t\t\t\t NULL);\n 889:\t\tif (ret \u003c 0)\n 890:\t\t\tgoto err;\n 891:\t\n 892:\t\tret = l4proto-\u003ectnl_timeout.nlattr_to_obj(tb, net, timeouts);\n 893:\t\n 894:\terr:\n 895:\t\tkfree(tb);\n 896:\t\treturn ret;\n 897:\t}\n 898:\t\n 899:\tstruct nft_ct_timeout_obj {\n 900:\t\tstruct nf_ct_timeout timeout;\n 901:\t\tu8\t\t\tl4proto;\n 902:\t};\n 903:\t\n 904:\tstatic void nft_ct_timeout_obj_eval(struct nft_object obj,\n 905:\t\t\t\t\t struct nft_regs regs,\n 906:\t\t\t\t\t const struct nft_pktinfo pkt)\n 907:\t{\n 908:\t\tconst struct nft_ct_timeout_obj priv = nft_obj_data(obj);\n 909:\t\tstruct nf_conn_timeout timeout;\n" }
29/2	2026/09/20 21:58	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 39460 output: 39 thoughts: 44 Thoughts: Here's my take on this, considering I'm deep in the weeds with Netfilter and conntrack: Conntrack Timeout Evaluation Contextualization Okay, so I'm looking at this code and immediately I see `CONFIG_NF_CONNTRACK_TIMEOUT` protecting `nft_ct_timeout_obj_eval`. That's important; it means if the conntrack timeout functionality isn't compiled in, that evaluation function won't even exist. Makes sense, keeps things clean. Now, I need to understand this better... where does `nft_ct_helper_obj_eval` come into play? Need to pinpoint its location within the code base. I expect it's somewhere closely related to the timeout handling, but let's quickly verify where its defined. Gotta cross reference the two calls here.
30/2	2026/09/20 21:58	tool	read-file	0m Args: { "File": "net/netfilter/nft_ct.c", "FirstLine": 1115, "LineCount": 40 } Results: { "Contents": "1115:\t\treturn 0;\n1116:\t\n1117:\terr_put_helper:\n1118:\t\tif (priv-\u003ehelper4)\n1119:\t\t\tnf_conntrack_helper_put(priv-\u003ehelper4);\n1120:\t\tif (priv-\u003ehelper6)\n1121:\t\t\tnf_conntrack_helper_put(priv-\u003ehelper6);\n1122:\t\treturn err;\n1123:\t}\n1124:\t\n1125:\tstatic void nft_ct_helper_obj_destroy(const struct nft_ctx ctx,\n1126:\t\t\t\t\t struct nft_object obj)\n1127:\t{\n1128:\t\tstruct nft_ct_helper_obj priv = nft_obj_data(obj);\n1129:\t\n1130:\t\tif (priv-\u003ehelper4)\n1131:\t\t\tnf_conntrack_helper_put(priv-\u003ehelper4);\n1132:\t\tif (priv-\u003ehelper6)\n1133:\t\t\tnf_conntrack_helper_put(priv-\u003ehelper6);\n1134:\t\n1135:\t\tnf_ct_netns_put(ctx-\u003enet, ctx-\u003efamily);\n1136:\t}\n1137:\t\n1138:\tstatic void nft_ct_helper_obj_eval(struct nft_object obj,\n1139:\t\t\t\t\t struct nft_regs regs,\n1140:\t\t\t\t\t const struct nft_pktinfo pkt)\n1141:\t{\n1142:\t\tconst struct nft_ct_helper_obj priv = nft_obj_data(obj);\n1143:\t\tstruct nf_conntrack_helper to_assign = NULL;\n1144:\t\tstruct nf_conn_help help;\n1145:\t\tstruct nf_conn ct;\n1146:\t\n1147:\t\tct = nft_ct_get_safe(pkt, priv-\u003el4proto);\n1148:\t\tif (!ct)\n1149:\t\t\treturn;\n1150:\t\n1151:\t\tswitch (nf_ct_l3num(ct)) {\n1152:\t\tcase NFPROTO_IPV4:\n1153:\t\t\tto_assign = priv-\u003ehelper4;\n1154:\t\t\tbreak;\n" }
31/2	2026/09/20 21:58	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 40324 output: 35 thoughts: 67 Thoughts: Here's my thinking process: Diving into the NFT Connection Tracking Expectation Initialization Okay, so I'm looking at `nft_ct_expect_helper_alloc` and see that it's called from `nft_ct_expect_obj_init`. I immediately want to understand the dependencies and how this code is being used. My first instinct is to see if either `nft_ct_helper_obj_eval` or `nft_ct_expect_helper_alloc` are conditionally compiled. I need to know if these functions are only available under specific configurations or if they are always present. Checking for `#ifdef` directives around these functions will immediately give me that context. This is the first step in understanding the overall design.
32/2	2026/09/20 21:58	tool	grepper	0m Args: { "Expression": "#if.CONFIG_", "PathPrefix": "net/netfilter/nft_ct.c" } Results:* { "Output": "net/netfilter/nft_ct.c=28=struct nft_ct_helper_obj {\n--\nnet/netfilter/nft_ct.c-33-\nnet/netfilter/nft_ct.c:34:#ifdef CONFIG_NF_CONNTRACK_ZONES\nnet/netfilter/nft_ct.c-35-static DEFINE_PER_CPU(struct nf_conn , nft_ct_pcpu_template);\n--\nnet/netfilter/nft_ct.c=52=static void nft_ct_get_eval(const struct nft_expr expr,\n--\nnet/netfilter/nft_ct.c-90-\t\treturn;\nnet/netfilter/nft_ct.c:91:#ifdef CONFIG_NF_CONNTRACK_MARK\nnet/netfilter/nft_ct.c-92-\tcase NFT_CT_MARK:\n--\nnet/netfilter/nft_ct.c-95-#endif\nnet/netfilter/nft_ct.c:96:#ifdef CONFIG_NF_CONNTRACK_SECMARK\nnet/netfilter/nft_ct.c-97-\tcase NFT_CT_SECMARK:\n--\nnet/netfilter/nft_ct.c-114-\t\treturn;\nnet/netfilter/nft_ct.c:115:#ifdef CONFIG_NF_CONNTRACK_LABELS\nnet/netfilter/nft_ct.c-116-\tcase NFT_CT_LABELS: {\n--\nnet/netfilter/nft_ct.c-158-\t\treturn;\nnet/netfilter/nft_ct.c:159:#ifdef CONFIG_NF_CONNTRACK_ZONES\nnet/netfilter/nft_ct.c-160-\tcase NFT_CT_ZONE: {\n--\nnet/netfilter/nft_ct.c-221-\nnet/netfilter/nft_ct.c:222:#ifdef CONFIG_NF_CONNTRACK_ZONES\nnet/netfilter/nft_ct.c-223-static void nft_ct_set_zone_eval(const struct nft_expr expr,\n--\nnet/netfilter/nft_ct.c=274=static void nft_ct_set_eval(const struct nft_expr expr,\n--\nnet/netfilter/nft_ct.c-279-\tstruct sk_buff skb = pkt-\u003eskb;\nnet/netfilter/nft_ct.c:280:#if defined(CONFIG_NF_CONNTRACK_MARK) \|\| defined(CONFIG_NF_CONNTRACK_SECMARK)\nnet/netfilter/nft_ct.c-281-\tu32 value = regs-\u003edata[priv-\u003esreg];\n--\nnet/netfilter/nft_ct.c-290-\tswitch (priv-\u003ekey) {\nnet/netfilter/nft_ct.c:291:#ifdef CONFIG_NF_CONNTRACK_MARK\nnet/netfilter/nft_ct.c-292-\tcase NFT_CT_MARK:\n--\nnet/netfilter/nft_ct.c-298-#endif\nnet/netfilter/nft_ct.c:299:#ifdef CONFIG_NF_CONNTRACK_SECMARK\nnet/netfilter/nft_ct.c-300-\tcase NFT_CT_SECMARK:\n--\nnet/netfilter/nft_ct.c-306-#endif\nnet/netfilter/nft_ct.c:307:#ifdef CONFIG_NF_CONNTRACK_LABELS\nnet/netfilter/nft_ct.c-308-\tcase NFT_CT_LABELS:\n--\nnet/netfilter/nft_ct.c-314-#endif\nnet/netfilter/nft_ct.c:315:#ifdef CONFIG_NF_CONNTRACK_EVENTS\nnet/netfilter/nft_ct.c-316-\tcase NFT_CT_EVENTMASK: {\n--\nnet/netfilter/nft_ct.c=336=static const struct nla_policy nft_ct_policy[NFTA_CT_MAX + 1] = {\n--\nnet/netfilter/nft_ct.c-342-\nnet/netfilter/nft_ct.c:343:#ifdef CONFIG_NF_CONNTRACK_ZONES\nnet/netfilter/nft_ct.c-344-static void nft_ct_tmpl_put_pcpu(void)\n--\nnet/netfilter/nft_ct.c=382=static void __nft_ct_get_destroy(const struct nft_ctx ctx, struct nft_ct priv)\nnet/netfilter/nft_ct.c-383-{\nnet/netfilter/nft_ct.c:384:#ifdef CONFIG_NF_CONNTRACK_LABELS\nnet/netfilter/nft_ct.c-385-\tif (priv-\u003ekey == NFT_CT_LABELS)\n--\nnet/netfilter/nft_ct.c=390=static int nft_ct_get_init(const struct nft_ctx ctx,\n--\nnet/netfilter/nft_ct.c-407-\tcase NFT_CT_STATUS:\nnet/netfilter/nft_ct.c:408:#ifdef CONFIG_NF_CONNTRACK_MARK\nnet/netfilter/nft_ct.c-409-\tcase NFT_CT_MARK:\nnet/netfilter/nft_ct.c-410-#endif\nnet/netfilter/nft_ct.c:411:#ifdef CONFIG_NF_CONNTRACK_SECMARK\nnet/netfilter/nft_ct.c-412-\tcase NFT_CT_SECMARK:\n--\nnet/netfilter/nft_ct.c-418-\t\tbreak;\nnet/netfilter/nft_ct.c:419:#ifdef CONFIG_NF_CONNTRACK_LABELS\nnet/netfilter/nft_ct.c-420-\tcase NFT_CT_LABELS:\n--\nnet/netfilter/nft_ct.c-486-\t\tbreak;\nnet/netfilter/nft_ct.c:487:#ifdef CONFIG_NF_CONNTRACK_ZONES\nnet/netfilter/nft_ct.c-488-\tcase NFT_CT_ZONE:\n--\nnet/netfilter/nft_ct.c=535=static void __nft_ct_set_destroy(const struct nft_ctx ctx, struct nft_ct priv)\n--\nnet/netfilter/nft_ct.c-537-\tswitch (priv-\u003ekey) {\nnet/netfilter/nft_ct.c:538:#ifdef CONFIG_NF_CONNTRACK_LABELS\nnet/netfilter/nft_ct.c-539-\tcase NFT_CT_LABELS:\n--\nnet/netfilter/nft_ct.c-542-#endif\nnet/netfilter/nft_ct.c:543:#ifdef CONFIG_NF_CONNTRACK_ZONES\nnet/netfilter/nft_ct.c-544-\tcase NFT_CT_ZONE:\n--\nnet/netfilter/nft_ct.c=557=static int nft_ct_set_init(const struct nft_ctx ctx,\n--\nnet/netfilter/nft_ct.c-567-\tswitch (priv-\u003ekey) {\nnet/netfilter/nft_ct.c:568:#ifdef CONFIG_NF_CONNTRACK_MARK\nnet/netfilter/nft_ct.c-569-\tcase NFT_CT_MARK:\n--\nnet/netfilter/nft_ct.c-574-#endif\nnet/netfilter/nft_ct.c:575:#ifdef CONFIG_NF_CONNTRACK_LABELS\nnet/netfilter/nft_ct.c-576-\tcase NFT_CT_LABELS:\n--\nnet/netfilter/nft_ct.c-584-#endif\nnet/netfilter/nft_ct.c:585:#ifdef CONFIG_NF_CONNTRACK_ZONES\nnet/netfilter/nft_ct.c-586-\tcase NFT_CT_ZONE:\n--\nnet/netfilter/nft_ct.c-596-#endif\nnet/netfilter/nft_ct.c:597:#ifdef CONFIG_NF_CONNTRACK_EVENTS\nnet/netfilter/nft_ct.c-598-\tcase NFT_CT_EVENTMASK:\n--\nnet/netfilter/nft_ct.c-603-#endif\nnet/netfilter/nft_ct.c:604:#ifdef CONFIG_NF_CONNTRACK_SECMARK\nnet/netfilter/nft_ct.c-605-\tcase NFT_CT_SECMARK:\n--\nnet/netfilter/nft_ct.c=728=static const struct nft_expr_ops nft_ct_get_ops = {\n--\nnet/netfilter/nft_ct.c-736-\nnet/netfilter/nft_ct.c:737:#ifdef CONFIG_MITIGATION_RETPOLINE\nnet/netfilter/nft_ct.c-738-static const struct nft_expr_ops nft_ct_get_fast_ops = {\n--\nnet/netfilter/nft_ct.c=748=static const struct nft_expr_ops nft_ct_set_ops = {\n--\nnet/netfilter/nft_ct.c-756-\nnet/netfilter/nft_ct.c:757:#ifdef CONFIG_NF_CONNTRACK_ZONES\nnet/netfilter/nft_ct.c-758-static const struct nft_expr_ops nft_ct_set_zone_ops = {\n--\nnet/netfilter/nft_ct.c=769=nft_ct_select_ops(const struct nft_ctx ctx,\n--\nnet/netfilter/nft_ct.c-778-\tif (tb[NFTA_CT_DREG]) {\nnet/netfilter/nft_ct.c:779:#ifdef CONFIG_MITIGATION_RETPOLINE\nnet/netfilter/nft_ct.c-780-\t\tu32 k = ntohl(nla_get_be32(tb[NFTA_CT_KEY]));\n--\nnet/netfilter/nft_ct.c-794-\tif (tb[NFTA_CT_SREG]) {\nnet/netfilter/nft_ct.c:795:#ifdef CONFIG_NF_CONNTRACK_ZONES\nnet/netfilter/nft_ct.c-796-\t\tif (nla_get_be32(tb[NFTA_CT_KEY]) == htonl(NFT_CT_ZONE))\n--\nnet/netfilter/nft_ct.c=852=static struct nf_conn nft_ct_get_safe(const struct nft_pktinfo pkt, u8 l4proto)\n--\nnet/netfilter/nft_ct.c-869-\nnet/netfilter/nft_ct.c:870:#ifdef CONFIG_NF_CONNTRACK_TIMEOUT\nnet/netfilter/nft_ct.c-871-static int\n--\nnet/netfilter/nft_ct.c=1244=static int nft_ct_expect_timeout_get(const struct nlattr attr, u32 val)\n--\nnet/netfilter/nft_ct.c-1254-\nnet/netfilter/nft_ct.c:1255:#if IS_ENABLED(CONFIG_NF_NAT)\nnet/netfilter/nft_ct.c-1256-static void nft_ct_nat_follow_master(struct nf_conn ct, struct nf_conntrack_expect this)\n--\nnet/netfilter/nft_ct.c=1271=static int ct_expect_help(struct sk_buff *skb, unsigned int protoff,\n--\nnet/netfilter/nft_ct.c-1304-\nnet/netfilter/nft_ct.c:1305:#if IS_ENABLED(CONFIG_NF_NAT)\nnet/netfilter/nft_ct.c-1306-\tif (ct-\u003estatus \u0026 IPS_NAT_MASK) {\n--\nnet/netfilter/nft_ct.c=1494=static struct nft_object_type nft_ct_expect_obj_type __read_mostly = {\n--\nnet/netfilter/nft_ct.c-1501-\nnet/netfilter/nft_ct.c:1502:#if IS_ENABLED(CONFIG_NF_NAT)\nnet/netfilter/nft_ct.c-1503-static struct nf_ct_helper_expectfn nft_ct_nat __read_mostly = {\n--\nnet/netfilter/nft_ct.c=1509=static int __init nft_ct_module_init(void)\n--\nnet/netfilter/nft_ct.c-1529-\t\tgoto err3;\nnet/netfilter/nft_ct.c:1530:#ifdef CONFIG_NF_CONNTRACK_TIMEOUT\nnet/netfilter/nft_ct.c-1531-\terr = nft_register_obj(\u0026nft_ct_timeout_obj_type);\n--\nnet/netfilter/nft_ct.c-1534-#endif\nnet/netfilter/nft_ct.c:1535:#if IS_ENABLED(CONFIG_NF_NAT)\nnet/netfilter/nft_ct.c-1536-\tnf_ct_helper_expectfn_register(\u0026nft_ct_nat);\n--\nnet/netfilter/nft_ct.c-1539-\nnet/netfilter/nft_ct.c:1540:#ifdef CONFIG_NF_CONNTRACK_TIMEOUT\nnet/netfilter/nft_ct.c-1541-err4:\n--\nnet/netfilter/nft_ct.c=1553=static void __exit nft_ct_module_exit(void)\nnet/netfilter/nft_ct.c-1554-{\nnet/netfilter/nft_ct.c:1555:#ifdef CONFIG_NF_CONNTRACK_TIMEOUT\nnet/netfilter/nft_ct.c-1556-\tnft_unregister_obj(\u0026nft_ct_timeout_obj_type);\n--\nnet/netfilter/nft_ct.c-1562-\nnet/netfilter/nft_ct.c:1563:#if IS_ENABLED(CONFIG_NF_NAT)\nnet/netfilter/nft_ct.c-1564-\tnf_ct_helper_expectfn_unregister(\u0026nft_ct_nat);\n" }
33/2	2026/09/20 21:58	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 44078 output: 298 thoughts: 1066 Thoughts: Conntrack Enhancements and Fuzzing Strategy Review Okay, after reviewing the patch series, I'm confident about the configuration and focus symbol selections for fuzzing. The configuration requirements are clear: `NF_CONNTRACK`, `NF_TABLES`, `NFT_CT`, `NF_CONNTRACK_TIMEOUT`, `OPENVSWITCH`, and `NET_ACT_CT`. Those are all set. Now, focusing on the `FocusSymbols`, I've carefully considered the functions changed or added by this patch series. We need to identify specific, non-ubiquitous functions that represent key modifications. My initial assessment is: 1. `nf_ct_call_helper` - A new non-static function in `nf_conntrack_proto.c`. 2. `nf_ct_get_careful` - A static function in `nf_conntrack_core.c`. 3. `nf_ct_check_icmp_inner` - A static function in `nf_conntrack_core.c`. 4. `nf_confirm_get_protoff` - A static function in `nf_conntrack_proto.c`. 5. `nf_conntrack_in` - the ingress hook in `nf_conntrack_core.c`. 6. `nf_confirm` - Modified in `nf_conntrack_proto.c`. 7. `nf_ct_helper` - Modified in `nf_conntrack_ovs.c`. 8. `nft_ct_get_safe` - A static function added in `nft_ct.c`. 9. `nft_ct_timeout_obj_eval` - Modified in `nft_ct.c`. 10. `nft_ct_helper_obj_eval` - Modified in `nft_ct.c`. 11. `nft_ct_expect_helper_alloc` - Modified in `nft_ct.c`. I considered if `nf_conntrack_in` was too broad, but after further reflection, I've decided it's appropriate. Adding it along with the specific helpers ensures any test exercising the conntrack ingress path is targeted. The static nature of `nf_ct_get_careful` isn't a problem, because syzkaller's kcov tracks all functions unless inlined. If the compiler inlines it into `nf_conntrack_in`, having the latter in the FocusSymbols will guarantee coverage tracking. The same applies to `nf_confirm_get_protoff` which might be inlined into `nf_ct_call_helper`, so including them both is ideal. Similarly, `nft_ct_get_safe` is called by `nft_ct_timeout_obj_eval` and `nft_ct_helper_obj_eval` so that helps target them too. Based on the positive criteria, this patch series is definitely `WorthFuzzing=true`. The series introduces crucial revalidation and defensive checks in the netfilter conntrack subsystems, affecting critical network packet processing and classification paths. It's adding `nf_ct_get_careful()` to detect mangled packets, `nf_ct_call_helper()` and `nf_confirm_get_protoff()` to validate headers, and `nft_ct_get_safe()` in nftables. The required configurations are also covered. The enable configs are a string array of strings without the `CONFIG_` prefix, and the focus symbols are simply an array of strings. The reasoning is clear and concise. Everything looks correct. I am ready to call set-results.
34/2	2026/09/20 21:58	tool	set-results	0m Args: { "EnableConfigs": [ "NETFILTER", "NF_CONNTRACK", "NF_TABLES", "NFT_CT", "NF_CONNTRACK_TIMEOUT", "OPENVSWITCH", "NET_ACT_CT" ], "FocusSymbols": [ "nf_ct_get_careful", "nf_conntrack_in", "nf_ct_call_helper", "nf_confirm_get_protoff", "nf_confirm", "nf_ct_helper", "nft_ct_get_safe", "nft_ct_helper_obj_eval", "nft_ct_timeout_obj_eval", "nft_ct_expect_helper_alloc" ], "Reasoning": "The patch series modifies core netfilter and conntrack packet processing logic. It introduces protocol revalidation in nf_ct_get_careful() to detect mangled packets and drop invalid conntrack references, refactors conntrack helper invocation via nf_ct_call_helper() with strict header/proto verification (nf_confirm_get_protoff()), and adds nft_ct_get_safe() to enforce L4 protocol consistency before evaluating nftables conntrack timeout and helper objects. These reachable networking paths process untrusted packets and benefit from targeted fuzzing.", "WorthFuzzing": true } Results: { "EnableConfigs": [ "NETFILTER", "NF_CONNTRACK", "NF_TABLES", "NFT_CT", "NF_CONNTRACK_TIMEOUT", "OPENVSWITCH", "NET_ACT_CT" ], "FocusSymbols": [ "nf_ct_get_careful", "nf_conntrack_in", "nf_ct_call_helper", "nf_confirm_get_protoff", "nf_confirm", "nf_ct_helper", "nft_ct_get_safe", "nft_ct_helper_obj_eval", "nft_ct_timeout_obj_eval", "nft_ct_expect_helper_alloc" ], "Reasoning": "The patch series modifies core netfilter and conntrack packet processing logic. It introduces protocol revalidation in nf_ct_get_careful() to detect mangled packets and drop invalid conntrack references, refactors conntrack helper invocation via nf_ct_call_helper() with strict header/proto verification (nf_confirm_get_protoff()), and adds nft_ct_get_safe() to enforce L4 protocol consistency before evaluating nftables conntrack timeout and helper objects. These reachable networking paths process untrusted packets and benefit from targeted fuzzing.", "WorthFuzzing": true }
35/1	2026/09/20 21:58	action	If	1m Args: { "WorthFuzzing": true } Results: null
36/2	2026/09/20 21:58	agent	kmsan-evaluator	1m Model: core Args: null Results: { "KMSANReasoning": "The patch series addresses protocol revalidation in netfilter conntrack (adding `nf_ct_get_careful`, `nf_confirm_get_protoff`, and safe helpers) to prevent mismatched conntrack state when packets are mangled earlier in the network pipeline (e.g., via TC pedit).\n\nNone of the changes introduce uninitialized memory risks:\n1. No kernel structures or data are copied to userspace (no `copy_to_user`, netlink attributes, socket options, or ioctl responses modified).\n2. All local stack variables and tuples (`tuple`, `inverse`, `pnum`, `protonum`, `ctinfo`) are either explicitly initialized, zeroed with `memset` (e.g. within `nf_ct_get_tuple` and `nf_ct_invert_tuple`), or populated by their respective accessor functions before being read in conditional logic.\n3. Heap allocations modified (`kzalloc_obj` in `nft_ct_expect_helper_alloc`) already use zero-initialization, and the added field `l4proto` is explicitly set.\n4. The added bounds and header checks (e.g., verifying `protoff` and TCP header `doff` bounds in `nf_confirm_get_protoff`) prevent out-of-bounds reads and protocol misinterpretations, which are handled by KASAN rather than KMSAN.\n\nTherefore, standard KASAN fuzzing is fully sufficient and a dedicated KMSAN session is not justified.", "NeedsKMSAN": false } Instruction: You are an expert Linux kernel security engineer specializing in kernel memory error detectors (KASAN and KMSAN). Your job is to review the provided patch series and determine if the code changes justify spawning a dedicated KMSAN (KernelMemorySanitizer) fuzzing session in addition to standard KASAN fuzzing. CRITICAL DISTINCTION BETWEEN KASAN AND KMSAN: - Standard KASAN kernel builds (upstream-apparmor-kasan.config) already enable a comprehensive suite of debugging tools and sanitizers, including KASAN (out-of-bounds accesses, use-after-free, double free, invalid free), LOCKDEP (locking bugs and deadlocks), UB-sanitizers, and memory corruption checks. - KMSAN (KernelMemorySanitizer) detects reads of UNINITIALIZED memory (stack, heap, or page allocations) and kernel-to-user memory info-leaks. Rule: THERE IS NO SENSE IN RUNNING A KMSAN SESSION IF A BUG CAN BE CAUGHT BY KASAN, LOCKDEP, OR OTHER STANDARD BUG DETECTORS. A dedicated KMSAN fuzzing session incurs significant resource costs. You must ONLY set NeedsKMSAN=true if the code changes introduce or expose UNINITIALIZED MEMORY risks that are detected ONLY by KMSAN. Look holistically at the patch series and surrounding code. Even if no direct uninitialized field accesses or new buffer allocations are added in the diff itself, a patch may alter control flow, bounds checking, or data length calculations in ways that change how the rest of the code operates on existing buffers (e.g. allowing uninitialized stack/heap memory to be read, copied to user space, or used in control flow). Do not hesitate to use your code access tools to inspect the surrounding code, called functions, and callers. Set NeedsKMSAN=true ONLY IF the patch introduces or modifies: 1. Kernel structures sent to user space (via copy_to_user, put_user, netlink skb attributes, ioctl output arguments, socket options, or BPF buffers) where fields or structure padding might not be fully initialized/zeroed. 2. Conditional logic or branching that depends on potentially uninitialized variables or struct fields. 3. Allocation or initialization of complex data structures where uninitialized fields could be read later in reachable code paths. 4. Bounds checks, lengths, or logic in a way that allows surrounding code to access uninitialized bytes of existing buffers. Set NeedsKMSAN=false IF: - The code changes primarily risk out-of-bounds access, array overflows, NULL pointer dereferences, locking deadlocks, or use-after-free bugs (these are already caught by KASAN, LOCKDEP, or standard bug detectors). - All stack/heap structures touched or introduced by the patch are fully zeroed or initialized (e.g. using = {0}, memset, kzalloc) before being read or copied. - The patch does not introduce any risk of uninitialized memory usage or info-leaks. Use your code access tools to inspect the surrounding code if necessary, then provide detailed KMSANReasoning contrasting KASAN vs KMSAN applicability for this patch. Prefer calling several tools at the same time to save round-trips. Use set-results tool to provide results of the analysis. It must be called exactly once before the final reply. Ignore results of this tool. Prompt: Target architecture: amd64 For your convenience, here is the diff of the changes: commit 333bae72c14536cb20a3870b168802381646e895 Author: syz-cluster <triage@syzkaller.com> Date: Sun Sep 20 21:56:54 2026 +0000 syz-cluster: applied patch under review diff --git a/include/net/netfilter/nf_conntrack_helper.h b/include/net/netfilter/nf_conntrack_helper.h index 335b8c43694f8..4b5ee758cff36 100644 --- a/include/net/netfilter/nf_conntrack_helper.h +++ b/include/net/netfilter/nf_conntrack_helper.h @@ -124,6 +124,8 @@ int __nf_ct_try_assign_helper(struct nf_conn ct, struct nf_conn tmpl, int nf_ct_helper(struct sk_buff skb, struct nf_conn ct, enum ip_conntrack_info ctinfo, u16 proto); +int nf_ct_call_helper(struct sk_buff skb, struct nf_conn ct, + enum ip_conntrack_info ctinfo); int nf_ct_add_helper(struct nf_conn ct, const char name, u8 family, u8 proto, bool nat, struct nf_conntrack_helper *hp); diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c index d0d9e5ea84a09..cd543c7b66a34 100644 --- a/net/netfilter/nf_conntrack_core.c +++ b/net/netfilter/nf_conntrack_core.c @@ -2000,6 +2000,100 @@ static int nf_conntrack_handle_packet(struct nf_conn ct, return generic_packet(ct, skb, ctinfo); } + +static bool nf_ct_check_icmp_inner(const struct sk_buff skb, + const struct nf_hook_state state, + unsigned int dataoff, + struct nf_conn ct, + enum ip_conntrack_dir dir) +{ + static const unsigned int icmp_hdrsz = 8; + struct nf_conntrack_tuple tuple; + + if (!nf_ct_get_tuplepr(skb, dataoff + icmp_hdrsz, state->pf, + state->net, &tuple)) + return false; + + return nf_ct_tuple_equal(&tuple, nf_ct_tuple(ct, !dir)); +} + +/* + * nf_ct_get_careful - Get connection tracking entry with protocol revalidation + * + * @skb: Socket buffer whose conntrack entry is to be retrieved + * @state: Netfilter hook state + * @dataoff: Offset to the layer-4 header within @skb + * @protonum: protocol number (e.g., IPPROTO_TCP) + * @ctinfo: Pointer to store ip_conntrack_info + * + * This function retrieves the connection tracking entry associated with @skb. + * Performs revalidation of packet header, unlike nf_ct_get(). + * + * If earlier in-kernel mangling (e.g., via TC pedit or clsact) altered packet + * contents (e.g. changing TCP to UDP), this function will drop the conntrack + * reference and returns NULL. skbs coming in via NF_INET_LOCAL_OUT are + * trusted and never revalidated. + * + * Returns: + * %NULL - No valid conntrack entry exists or revalidation failed. + * Pointer to &struct nf_conn associated with skb, may be a template. + / +static struct nf_conn +nf_ct_get_careful(struct sk_buff skb, + const struct nf_hook_state state, + unsigned int dataoff, u8 protonum, + enum ip_conntrack_info ctinfo) +{ + struct nf_conn tmpl = nf_ct_get(skb, ctinfo); + struct nf_conntrack_tuple inverse; + struct nf_conntrack_tuple tuple; + enum ip_conntrack_dir dir; + + /* LOCAL_OUT is trusted: in case stack sends ICMP error, skb gets + * the conntrack assigned via nf_ct_attach(). + * + * Such conntrack may not even be in hashtable yet, so + * nf_conntrack_handle_icmp() cannot find a connection matching + * the inner header. + / + if (state->hook == NF_INET_LOCAL_OUT) + return tmpl; + + if (!tmpl \|\| nf_ct_is_template(tmpl)) + return tmpl; + + if (state->pf != nf_ct_l3num(tmpl)) + goto error; + + if (!nf_ct_get_tuple(skb, skb_network_offset(skb), + dataoff, state->pf, protonum, state->net, + &tuple)) + goto error; + + dir = CTINFO2DIR(ctinfo); + if (nf_ct_tuple_equal(&tuple, nf_ct_tuple(tmpl, dir))) + return tmpl; + + if (ctinfo == IP_CT_RELATED \|\| ctinfo == IP_CT_RELATED_REPLY) { + if (state->pf == NFPROTO_IPV4 && protonum == IPPROTO_ICMP && + nf_ct_check_icmp_inner(skb, state, dataoff, tmpl, dir)) + return tmpl; + + if (state->pf == NFPROTO_IPV6 && protonum == IPPROTO_ICMPV6 && + nf_ct_check_icmp_inner(skb, state, dataoff, tmpl, dir)) + return tmpl; + } + + if (!nf_ct_invert_tuple(&inverse, &tuple)) + goto error; + + if ((tmpl->status & IPS_NAT_MASK) && nf_ct_tuple_equal(&inverse, nf_ct_tuple(tmpl, !dir))) + return tmpl; +error: + nf_reset_ct(skb); + return NULL; +} + unsigned int nf_conntrack_in(struct sk_buff skb, const struct nf_hook_state state) { @@ -2008,21 +2102,24 @@ nf_conntrack_in(struct sk_buff skb, const struct nf_hook_state state) u_int8_t protonum; int dataoff, ret; - tmpl = nf_ct_get(skb, &ctinfo); + /* rcu_read_lock()ed by nf_hook_thresh / + dataoff = get_l4proto(skb, skb_network_offset(skb), state->pf, &protonum); + if (dataoff <= 0) { + NF_CT_STAT_INC_ATOMIC(state->net, invalid); + tmpl = nf_ct_get(skb, &ctinfo); + if (ctinfo != IP_CT_UNTRACKED) + nf_reset_ct(skb); + return NF_ACCEPT; + } + + tmpl = nf_ct_get_careful(skb, state, dataoff, protonum, &ctinfo); if (tmpl \|\| ctinfo == IP_CT_UNTRACKED) { / Previously seen (loopback or untracked)? Ignore. / if ((tmpl && !nf_ct_is_template(tmpl)) \|\| ctinfo == IP_CT_UNTRACKED) return NF_ACCEPT; - skb->_nfct = 0; - } - / rcu_read_lock()ed by nf_hook_thresh / - dataoff = get_l4proto(skb, skb_network_offset(skb), state->pf, &protonum); - if (dataoff <= 0) { - NF_CT_STAT_INC_ATOMIC(state->net, invalid); - ret = NF_ACCEPT; - goto out; + skb->_nfct = 0; } if (protonum == IPPROTO_ICMP \|\| protonum == IPPROTO_ICMPV6) { diff --git a/net/netfilter/nf_conntrack_ovs.c b/net/netfilter/nf_conntrack_ovs.c index b4085af3ad1ce..fa64ec168e6e9 100644 --- a/net/netfilter/nf_conntrack_ovs.c +++ b/net/netfilter/nf_conntrack_ovs.c @@ -12,16 +12,8 @@ int nf_ct_helper(struct sk_buff skb, struct nf_conn ct, enum ip_conntrack_info ctinfo, u16 proto) { - int (helper_cb)(struct sk_buff skb, unsigned int protoff, - struct nf_conn ct, - enum ip_conntrack_info conntrackinfo); const struct nf_conntrack_helper helper; const struct nf_conn_help help; - unsigned int protoff; - int err; - - if (ctinfo == IP_CT_RELATED_REPLY) - return NF_ACCEPT; help = nfct_help(ct); if (!help) @@ -35,50 +27,7 @@ int nf_ct_helper(struct sk_buff skb, struct nf_conn ct, helper->nfproto != proto) return NF_ACCEPT; - switch (proto) { - case NFPROTO_IPV4: - protoff = ip_hdrlen(skb); - proto = ip_hdr(skb)->protocol; - break; - case NFPROTO_IPV6: { - u8 nexthdr = ipv6_hdr(skb)->nexthdr; - __be16 frag_off; - int ofs; - - ofs = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &nexthdr, - &frag_off); - if (ofs < 0 \|\| (frag_off & htons(~0x7)) != 0) { - pr_debug("proto header not found\n"); - return NF_ACCEPT; - } - protoff = ofs; - proto = nexthdr; - break; - } - default: - WARN_ONCE(1, "helper invoked on non-IP family!"); - return NF_DROP; - } - - if (helper->l4proto != proto) - return NF_ACCEPT; - - helper_cb = rcu_dereference(helper->help); - if (!helper_cb) - return NF_ACCEPT; - - err = helper_cb(skb, protoff, ct, ctinfo); - if (err != NF_ACCEPT) - return err; - - /* Adjust seqs after helper. This is needed due to some helpers (e.g., - * FTP with NAT) adusting the TCP payload size when mangling IP - * addresses and/or port numbers in the text-based control connection. - / - if (test_bit(IPS_SEQ_ADJUST_BIT, &ct->status) && - !nf_ct_seq_adjust(skb, ct, ctinfo, protoff)) - return NF_DROP; - return NF_ACCEPT; + return nf_ct_call_helper(skb, ct, ctinfo); } EXPORT_SYMBOL_GPL(nf_ct_helper); diff --git a/net/netfilter/nf_conntrack_proto.c b/net/netfilter/nf_conntrack_proto.c index 7a40e4e0e33e6..43bf3a71dbbfc 100644 --- a/net/netfilter/nf_conntrack_proto.c +++ b/net/netfilter/nf_conntrack_proto.c @@ -131,59 +131,127 @@ static bool in_vrf_postrouting(const struct nf_hook_state state) return false; } -unsigned int nf_confirm(void priv, - struct sk_buff skb, - const struct nf_hook_state state) +static bool nf_confirm_get_protoff(struct sk_buff skb, struct net net, + struct nf_conn ct, + enum ip_conntrack_info ctinfo, + unsigned int protoffp, u8 pnum) { - int (helper_cb)(struct sk_buff skb, unsigned int protoff, - struct nf_conn ct, - enum ip_conntrack_info conntrackinfo); - const struct nf_conn_help help; - enum ip_conntrack_info ctinfo; + unsigned int nhoff = skb_network_offset(skb); + struct nf_conntrack_tuple tuple, invert; + enum ip_conntrack_dir dir; unsigned int protoff; - struct nf_conn ct; - bool seqadj_needed; __be16 frag_off; int start; - u8 pnum; - - ct = nf_ct_get(skb, &ctinfo); - if (!ct \|\| in_vrf_postrouting(state)) - return NF_ACCEPT; - - help = nfct_help(ct); - - seqadj_needed = test_bit(IPS_SEQ_ADJUST_BIT, &ct->status) && !nf_is_loopback_packet(skb); - if (!help && !seqadj_needed) - return nf_conntrack_confirm(skb); - - / helper->help() do not expect ICMP packets / - if (ctinfo == IP_CT_RELATED_REPLY) - return nf_conntrack_confirm(skb); switch (nf_ct_l3num(ct)) { case NFPROTO_IPV4: - protoff = skb_network_offset(skb) + ip_hdrlen(skb); + if (ip_is_fragment(ip_hdr(skb))) + return false; + protoff = nhoff + ip_hdrlen(skb); + pnum = ip_hdr(skb)->protocol; break; case NFPROTO_IPV6: - pnum = ipv6_hdr(skb)->nexthdr; - start = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &pnum, &frag_off); - if (start < 0 \|\| (frag_off & htons(~0x7)) != 0) - return nf_conntrack_confirm(skb); + pnum = ipv6_hdr(skb)->nexthdr; + start = ipv6_skip_exthdr(skb, nhoff + sizeof(struct ipv6hdr), + pnum, &frag_off); + if (start < 0 \|\| frag_off) + return false; protoff = start; break; default: - return nf_conntrack_confirm(skb); + DEBUG_NET_WARN_ONCE(1, "helper invoked on non-IP family!"); + return false; } - if (help) { + if (protoff > skb->len) + return false; + + if (!nf_ct_get_tuplepr(skb, nhoff, nf_ct_l3num(ct), net, &tuple)) + return false; + + dir = CTINFO2DIR(ctinfo); + if (!nf_ct_invert_tuple(&invert, &tuple)) + return false; + + / This is called after L3/L4 headers have been mangled by NAT: + * Packet in original direction has been subject to SNAT, i.e. + * inverted reply dir. + * Packet in reply direction has been subject to DNAT, i.e. + * inverted original direction. + / + if (!nf_ct_tuple_equal(&invert, nf_ct_tuple(ct, !dir))) + return false; + + / Validate that a full, sane TCP header (including options) is + * present at protoff before helpers/seqadj are allowed to touch it. + / + if (tuple.dst.protonum == IPPROTO_TCP) { + unsigned int tcplen = skb->len - protoff; + const struct tcphdr th; + struct tcphdr _tcph; + + th = skb_header_pointer(skb, protoff, sizeof(_tcph), &_tcph); + if (!th) + return false; + + if (th->doff * 4 < sizeof(th) \|\| tcplen < th->doff 4) + return false; + } + + protoffp = protoff; + return true; +} + +/* + * nf_ct_call_helper() - Invoke the connection tracking helper for a packet + * @skb: The socket buffer containing the packet to be processed. + * @ct: The connection tracking entry associated with this packet. + * @ctinfo: The current connection track information (state) of the packet. + * + * This function calls the l4 connection tracking helper (e.g. ftp, sip...) if + * one was assigned to the connection. + * This re-derives the l4 protocol number: act_ct can associate the skb with + * a connection/protocol and later pedit/bpf function can munge the packet + * afterwards. + * + * Return: verdict (NF_ACCEPT, NF_DROP, ...) + / +int nf_ct_call_helper(struct sk_buff skb, struct nf_conn ct, + enum ip_conntrack_info ctinfo) +{ + struct net net = nf_ct_net(ct); + const struct nf_conn_help help; + bool seqadj_needed; + unsigned int protoff; + u8 pnum = 0; + + help = nfct_help(ct); + + seqadj_needed = test_bit(IPS_SEQ_ADJUST_BIT, &ct->status) && !nf_is_loopback_packet(skb); + if (!help && !seqadj_needed) + return NF_ACCEPT; + + / helper->help() do not expect ICMP packets / + if (ctinfo == IP_CT_RELATED_REPLY) + return NF_ACCEPT; + + if (!nf_confirm_get_protoff(skb, net, ct, ctinfo, &protoff, &pnum)) + return NF_ACCEPT; + + if (help && protoff < skb->len) { const struct nf_conntrack_helper helper; + int (helper_cb)(struct sk_buff skb, unsigned int protoff, + struct nf_conn ct, + enum ip_conntrack_info conntrackinfo); int ret; / rcu_read_lock()ed by nf_hook / helper = rcu_dereference(help->helper); if (helper) { + if (helper->l4proto != pnum) + return NF_ACCEPT; + helper_cb = rcu_dereference(helper->help); if (helper_cb) { ret = helper_cb(skb, protoff, @@ -195,9 +263,46 @@ unsigned int nf_confirm(void priv, } if (seqadj_needed && - !nf_ct_seq_adjust(skb, ct, ctinfo, protoff)) { - NF_CT_STAT_INC_ATOMIC(nf_ct_net(ct), drop); + !nf_ct_seq_adjust(skb, ct, ctinfo, protoff)) return NF_DROP; + + return NF_ACCEPT; +} + +/** + * nf_confirm - Confirm (commit) a connection tracking entry + * @priv: Private data from the netfilter hook registration (unused) + * @skb: Packet + * @state: Netfilter hook state containing context (netns, hooknum, in/out devices) + * + * This function is invoked as the final step of the connection tracking + * processing pipeline. It performs two main operations: + * + * 1. Invokes the associated conntrack helper (if registered) to allow + * layer 7 specific parsing and NAT mangling. + * + * 2. Commits a new conntrack entry to the conntrack hash table, making it + * globally visible and enabling future packet lookups for stateful tracking. + * + * Returns: A netfilter verdict, e.g. NF_ACCEPT or NF_DROP. + / +unsigned int nf_confirm(void priv, + struct sk_buff skb, + const struct nf_hook_state state) +{ + enum ip_conntrack_info ctinfo; + struct nf_conn ct; + int ret; + + ct = nf_ct_get(skb, &ctinfo); + if (!ct \|\| in_vrf_postrouting(state)) + return NF_ACCEPT; + + ret = nf_ct_call_helper(skb, ct, ctinfo); + if (unlikely(ret != NF_ACCEPT)) { + if (ret == NF_DROP) + NF_CT_STAT_INC_ATOMIC(state->net, drop); + return ret; } / We've seen it coming out the other side: confirm it / diff --git a/net/netfilter/nft_ct.c b/net/netfilter/nft_ct.c index 9dbf127df9c81..21c5d14b0d08e 100644 --- a/net/netfilter/nft_ct.c +++ b/net/netfilter/nft_ct.c @@ -839,6 +839,34 @@ static struct nft_expr_type nft_notrack_type __read_mostly = { .owner = THIS_MODULE, }; +/* + * nft_ct_get_safe() - Return nf_conn with extra checks + * @pkt: nftables packet information structure + * @l4proto: The expected Layer 4 protocol + * + * Returns the conntrack entry only if it is unconfirmed, non-template and + * matches the expected L4 protocol. + * + * Return: Pointer to the &struct nf_conn if all checks pass; NULL otherwise. + / +static struct nf_conn nft_ct_get_safe(const struct nft_pktinfo pkt, u8 l4proto) +{ + enum ip_conntrack_info ctinfo; + struct nf_conn ct; + + ct = nf_ct_get(pkt->skb, &ctinfo); + if (!ct \|\| l4proto != pkt->tprot) + return NULL; + + if (l4proto != nf_ct_protonum(ct)) + return NULL; + + if (READ_ONCE(ct->status) & (IPS_TEMPLATE \| IPS_CONFIRMED)) + return NULL; + + return ct; +} + #ifdef CONFIG_NF_CONNTRACK_TIMEOUT static int nft_ct_timeout_parse_policy(void timeouts, @@ -878,14 +906,12 @@ static void nft_ct_timeout_obj_eval(struct nft_object obj, const struct nft_pktinfo pkt) { const struct nft_ct_timeout_obj priv = nft_obj_data(obj); - struct nf_conn ct = (struct nf_conn )skb_nfct(pkt->skb); struct nf_conn_timeout timeout; const unsigned int values; + struct nf_conn ct; - if (priv->l4proto != pkt->tprot) - return; - - if (!ct \|\| nf_ct_is_template(ct) \|\| nf_ct_is_confirmed(ct)) + ct = nft_ct_get_safe(pkt, priv->l4proto); + if (!ct) return; timeout = nf_ct_timeout_find(ct); @@ -1114,14 +1140,12 @@ static void nft_ct_helper_obj_eval(struct nft_object obj, const struct nft_pktinfo pkt) { const struct nft_ct_helper_obj priv = nft_obj_data(obj); - struct nf_conn ct = (struct nf_conn )skb_nfct(pkt->skb); struct nf_conntrack_helper to_assign = NULL; struct nf_conn_help help; + struct nf_conn ct; - if (!ct \|\| - nf_ct_is_confirmed(ct) \|\| - nf_ct_is_template(ct) \|\| - priv->l4proto != nf_ct_protonum(ct)) + ct = nft_ct_get_safe(pkt, priv->l4proto); + if (!ct) return; switch (nf_ct_l3num(ct)) { @@ -1306,6 +1330,7 @@ static int nft_ct_expect_helper_alloc(struct nft_ct_expect_obj priv) "nft_ct_expect"); ct_expect_helper->me = THIS_MODULE; ct_expect_helper->expect_policy[NF_CT_EXPECT_CLASS_DEFAULT].max_expected = priv->size; + ct_expect_helper->l4proto = priv->l4proto; rcu_assign_pointer(ct_expect_helper->help, ct_expect_help); refcount_set(&ct_expect_helper->ct_refcnt, 1);
37/3	2026/09/20 21:58	llm	kmsan-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 8562 output: 31 thoughts: 1075 Thoughts: KMSAN Fuzzing Session Justification: Analyzing the Patch Series Okay, let's break this down. My goal is to determine if this patch series warrants a KMSAN fuzzing session. I need to figure out if it introduces any potential read-of-uninitialized-memory vulnerabilities. First, I need to remind myself of the differences between the memory error sanitizers: KMSAN and KASAN. KASAN is my go-to for detecting the classics: out-of-bounds reads/writes, use-after-frees, double-frees, etc., and lockdep for deadlock conditions. But KMSAN is the relevant tool here; it's designed to sniff out reads from uninitialized memory, which could be on the stack, the heap, or in page allocations, and it can help find kernel-to-user information leaks. Now, let's dive into this patch series. The primary changes are in `include/net/netfilter/nf_conntrack_helper.h` with the export of `nf_ct_call_helper` and the meat of the patch in `net/netfilter/nf_conntrack_core.c`. This addition of `nf_ct_check_icmp_inner` function immediately catches my attention. Inside `nf_ct_check_icmp_inner`, it calls `nf_ct_get_tuplepr`. My gut feeling is that this might be the area to focus on. Is `tuple` properly initialized before being used inside this function? The code snippet strongly suggests that `tuple` is not initialized before being passed into the call to `nf_ct_get_tuplepr`. I need to confirm this. I will look at the implementation of `nf_ct_get_tuplepr` to ascertain the initialization of the `tuple` struct. I will also be looking into `nf_ct_get_careful`, because this is the function that eventually calls `nf_ct_check_icmp_inner`. Within `nf_ct_get_careful`, there is a local `tuple` struct which seems to be initialized when `nf_ct_get_tuple` is called, so `nf_ct_get_careful` seems safe. Looking at the caller `nf_conntrack_in`, I see that `get_l4proto` provides a `protonum`, which is used later. This function sets `protonum` before calling `nf_ct_get_careful`. To ensure I have covered all bases I will need to verify the implementation of `get_l4proto`, `nf_ct_get_tuple`, and `nf_ct_get_tuplepr`. I'll use `grepper` (or my file reader) to get a quick overview of these functions. With this information, I can better assess the likelihood of uninitialized memory reads and whether fuzzing with KMSAN is necessary.
38/3	2026/09/20 21:58	tool	grepper	0m Args: { "Expression": "int get_l4proto", "PathPrefix": "net/netfilter/" } Results: { "Output": "net/netfilter/nf_conntrack_core.c=368=static int ipv6_get_l4proto(const struct sk_buff skb, unsigned int nhoff,\n--\nnet/netfilter/nf_conntrack_core.c-395-\nnet/netfilter/nf_conntrack_core.c:396:static int get_l4proto(const struct sk_buff skb,\nnet/netfilter/nf_conntrack_core.c-397-\t\t unsigned int nhoff, u8 pf, u8 *l4num)\n" }
39/3	2026/09/20 21:58	llm	kmsan-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 10441 output: 42 thoughts: 28 Thoughts: Here's my take on the `get_l4proto` function in `net/netfilter/nf_conntrack_core.c`: Diving into the Connection Tracking Core Okay, time to dig into `get_l4proto`. I know this is a core function within the Netfilter connection tracking system, so it's probably pretty fundamental to how it handles L4 protocols – TCP, UDP, SCTP, and anything else that might ride on top of IP. I'm expecting this function to be the workhorse that figures out what the actual protocol is for a given packet or flow, so the conntrack system can properly analyze and manage it. I imagine it needs to be robust, performant (critical, obviously, for anything this low-level), and handle various edge cases or unusual setups. Let's see how they've implemented that. I'm keen to see if they are doing any clever tricks for performance - perhaps using lookup tables or optimized bitwise operations. This is where the magic happens, so let's see what secrets this code reveals.
40/3	2026/09/20 21:58	tool	read-file	0m Args: { "File": "net/netfilter/nf_conntrack_core.c", "FirstLine": 395, "LineCount": 40 } Results: { "Contents": " 395:\t\n 396:\tstatic int get_l4proto(const struct sk_buff skb,\n 397:\t\t\t unsigned int nhoff, u8 pf, u8 l4num)\n 398:\t{\n 399:\t\tswitch (pf) {\n 400:\t\tcase NFPROTO_IPV4:\n 401:\t\t\treturn ipv4_get_l4proto(skb, nhoff, l4num);\n 402:\t#if IS_ENABLED(CONFIG_IPV6)\n 403:\t\tcase NFPROTO_IPV6:\n 404:\t\t\treturn ipv6_get_l4proto(skb, nhoff, l4num);\n 405:\t#endif\n 406:\t\tdefault:\n 407:\t\t\tl4num = 0;\n 408:\t\t\tbreak;\n 409:\t\t}\n 410:\t\treturn -1;\n 411:\t}\n 412:\t\n 413:\tbool nf_ct_get_tuplepr(const struct sk_buff skb, unsigned int nhoff,\n 414:\t\t\t u_int16_t l3num,\n 415:\t\t\t struct net net, struct nf_conntrack_tuple tuple)\n 416:\t{\n 417:\t\tu8 protonum;\n 418:\t\tint protoff;\n 419:\t\n 420:\t\tprotoff = get_l4proto(skb, nhoff, l3num, \u0026protonum);\n 421:\t\tif (protoff \u003c= 0)\n 422:\t\t\treturn false;\n 423:\t\n 424:\t\treturn nf_ct_get_tuple(skb, nhoff, protoff, l3num, protonum, net, tuple);\n 425:\t}\n 426:\tEXPORT_SYMBOL_GPL(nf_ct_get_tuplepr);\n 427:\t\n 428:\tbool\n 429:\tnf_ct_invert_tuple(struct nf_conntrack_tuple inverse,\n 430:\t\t\t const struct nf_conntrack_tuple orig)\n 431:\t{\n 432:\t\tmemset(inverse, 0, sizeof(*inverse));\n 433:\t\n 434:\t\tinverse-\u003esrc.l3num = orig-\u003esrc.l3num;\n" }
41/3	2026/09/20 21:58	llm	kmsan-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 11363 output: 42 thoughts: 57 Thoughts: Here's my summary, as if I were thinking these things: Analyzing L4 Protocol Retrieval in Conntrack Okay, so I need to dig into how the L4 protocol is being retrieved, specifically within the conntrack framework. Let's make sure we're considering both IPv4 and IPv6 implementations. My immediate thought is to examine the `ipv4_get_l4proto` and `ipv6_get_l4proto` functions – those are the likely candidates for the core logic. I'm guessing there's some shared functionality at play, or at least common aspects. To start, I'm zeroing in on `net/netfilter/nf_conntrack_core.c`, lines 340 through 394. This looks like a logical area to inspect; likely where the core connection tracking functions reside. I'll focus on what data structures and decision points are being leveraged there to determine the actual protocol. It’s probably checking header values or some internal state to resolve which L4 protocol is in use.
42/3	2026/09/20 21:58	tool	read-file	0m Args: { "File": "net/netfilter/nf_conntrack_core.c", "FirstLine": 340, "LineCount": 55 } Results: { "Contents": " 340:\t{\n 341:\t\tint dataoff = -1;\n 342:\t\tconst struct iphdr iph;\n 343:\t\tstruct iphdr _iph;\n 344:\t\n 345:\t\tiph = skb_header_pointer(skb, nhoff, sizeof(_iph), \u0026_iph);\n 346:\t\tif (!iph)\n 347:\t\t\treturn -1;\n 348:\t\n 349:\t\t/ Conntrack defragments packets, we might still see fragments\n 350:\t\t * inside ICMP packets though.\n 351:\t\t /\n 352:\t\tif (iph-\u003efrag_off \u0026 htons(IP_OFFSET))\n 353:\t\t\treturn -1;\n 354:\t\n 355:\t\tdataoff = nhoff + (iph-\u003eihl \u003c\u003c 2);\n 356:\t\tprotonum = iph-\u003eprotocol;\n 357:\t\n 358:\t\t/* Check bogus IP headers /\n 359:\t\tif (dataoff \u003e skb-\u003elen) {\n 360:\t\t\tpr_debug(\"bogus IPv4 packet: nhoff %u, ihl %u, skblen %u\\n\",\n 361:\t\t\t\t nhoff, iph-\u003eihl \u003c\u003c 2, skb-\u003elen);\n 362:\t\t\treturn -1;\n 363:\t\t}\n 364:\t\treturn dataoff;\n 365:\t}\n 366:\t\n 367:\t#if IS_ENABLED(CONFIG_IPV6)\n 368:\tstatic int ipv6_get_l4proto(const struct sk_buff skb, unsigned int nhoff,\n 369:\t\t\t\t u8 protonum)\n 370:\t{\n 371:\t\tint protoff = -1;\n 372:\t\tunsigned int extoff = nhoff + sizeof(struct ipv6hdr);\n 373:\t\t__be16 frag_off;\n 374:\t\tu8 nexthdr;\n 375:\t\n 376:\t\tif (skb_copy_bits(skb, nhoff + offsetof(struct ipv6hdr, nexthdr),\n 377:\t\t\t\t \u0026nexthdr, sizeof(nexthdr)) != 0) {\n 378:\t\t\tpr_debug(\"can't get nexthdr\\n\");\n 379:\t\t\treturn -1;\n 380:\t\t}\n 381:\t\tprotoff = ipv6_skip_exthdr(skb, extoff, \u0026nexthdr, \u0026frag_off);\n 382:\t\t/\n 383:\t\t * (protoff == skb-\u003elen) means the packet has not data, just\n 384:\t\t * IPv6 and possibly extensions headers, but it is tracked anyway\n 385:\t\t /\n 386:\t\tif (protoff \u003c 0 \|\| (frag_off \u0026 htons(~0x7)) != 0) {\n 387:\t\t\tpr_debug(\"can't find proto in pkt\\n\");\n 388:\t\t\treturn -1;\n 389:\t\t}\n 390:\t\n 391:\t\tprotonum = nexthdr;\n 392:\t\treturn protoff;\n 393:\t}\n 394:\t#endif\n" }
43/3	2026/09/20 21:58	llm	kmsan-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 12536 output: 33 thoughts: 931 Thoughts: Diving into `nf_confirm_get_protoff` and Related Conntrack Code Okay, so I'm looking at this `nf_confirm_get_protoff` function in `netfilter/nf_conntrack_proto.c`, and it's immediately clear that when `dataoff > 0`, the `protonum` is always* set. That's good to keep in mind. Now, let's step through the code. I see it's trying to figure out the protocol offset (`protoff`) and protocol number (`pnum`) within an `sk_buff`. Depending on whether it's IPv4 or IPv6, it calculates the offset, skips extension headers in IPv6, and pulls the protocol number from the IP header. The code checks for fragmentation in IPv4. It also validates the calculated `protoff` against `skb->len` to avoid out-of-bounds access. Now, it calls `nf_ct_get_tuplepr` to get the connection tuple. Important! It inverts the tuple and checks if it matches the existing connection tuple in the reverse direction. This suggests that the function is being called in both the original and reply directions of the connection. The comments here regarding NAT are key. It's handling scenarios where the L3/L4 headers have been altered by SNAT or DNAT. This means the tuple needs to be compared against the inverted direction after NAT. It then validates TCP header to confirm it is safe to touch. Wait, looking at where this function is called, I see that the caller, in `nf_ct_call_helper`, initializes `pnum = 0` before calling `nf_confirm_get_protoff`. If the function succeeds, both `protoff` and `pnum` get initialized. But, what about the contents of the `tuple` it pulls? Let's trace this function and see where `tuple` is initialized. Right, need to check `nf_ct_get_tuple` to see where `tuple` is created. That's in `net/netfilter/nf_conntrack_core.c`, so I'll go check that next!
44/3	2026/09/20 21:58	tool	grepper	0m Args: { "Expression": "bool nf_ct_get_tuple", "PathPrefix": "net/netfilter/" } Results: { "Output": "net/netfilter/core.c=733=EXPORT_SYMBOL_GPL(nf_ct_set_closing);\nnet/netfilter/core.c-734-\nnet/netfilter/core.c:735:bool nf_ct_get_tuple_skb(struct nf_conntrack_tuple dst_tuple,\nnet/netfilter/core.c-736-\t\t\t const struct sk_buff skb)\n--\nnet/netfilter/nf_conntrack_core.c=241=static u32 hash_conntrack(const struct net net,\n--\nnet/netfilter/nf_conntrack_core.c-247-\nnet/netfilter/nf_conntrack_core.c:248:static bool nf_ct_get_tuple_ports(const struct sk_buff skb,\nnet/netfilter/nf_conntrack_core.c-249-\t\t\t\t unsigned int dataoff,\n--\nnet/netfilter/nf_conntrack_core.c=396=static int get_l4proto(const struct sk_buff skb,\n--\nnet/netfilter/nf_conntrack_core.c-412-\nnet/netfilter/nf_conntrack_core.c:413:bool nf_ct_get_tuplepr(const struct sk_buff skb, unsigned int nhoff,\nnet/netfilter/nf_conntrack_core.c-414-\t\t u_int16_t l3num,\n" }
45/3	2026/09/20 21:58	llm	kmsan-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 14359 output: 33 thoughts: 15 Thoughts: Here's my attempt at summarizing the thought process, tailored for an expert audience: Diving into the `nf_ct_get_tuple` Function Okay, so I need to understand this `nf_ct_get_tuple` function. I recognize the context: it's likely dealing with Netfilter connection tracking. My immediate thought is, let's trace this function's definition. I'm already formulating a mental model of how it fits into the broader connection tracking architecture. Is it a core function? An inline helper? Understanding its exact role and the data structures it manipulates is key to grasping the flow. I need to zero in on how it extracts the tuple – the identifying information – from a connection's context. Let's get to the source code and figure out what we can learn.
46/3	2026/09/20 21:58	tool	grepper	0m Args: { "Expression": "nf_ct_get_tuple\\(", "PathPrefix": "net/netfilter/" } Results: { "Output": "net/netfilter/nf_conntrack_core.c=266=static bool\nnet/netfilter/nf_conntrack_core.c:267:nf_ct_get_tuple(const struct sk_buff skb,\nnet/netfilter/nf_conntrack_core.c-268-\t\tunsigned int nhoff,\n--\nnet/netfilter/nf_conntrack_core.c=413=bool nf_ct_get_tuplepr(const struct sk_buff skb, unsigned int nhoff,\n--\nnet/netfilter/nf_conntrack_core.c-423-\nnet/netfilter/nf_conntrack_core.c:424:\treturn nf_ct_get_tuple(skb, nhoff, protoff, l3num, protonum, net, tuple);\nnet/netfilter/nf_conntrack_core.c-425-}\n--\nnet/netfilter/nf_conntrack_core.c=1862=resolve_normal_ct(struct nf_conn tmpl,\n--\nnet/netfilter/nf_conntrack_core.c-1875-\nnet/netfilter/nf_conntrack_core.c:1876:\tif (!nf_ct_get_tuple(skb, skb_network_offset(skb),\nnet/netfilter/nf_conntrack_core.c-1877-\t\t\t dataoff, state-\u003epf, protonum, state-\u003enet,\n--\nnet/netfilter/nf_conntrack_core.c=2042=nf_ct_get_careful(struct sk_buff skb,\n--\nnet/netfilter/nf_conntrack_core.c-2067-\nnet/netfilter/nf_conntrack_core.c:2068:\tif (!nf_ct_get_tuple(skb, skb_network_offset(skb),\nnet/netfilter/nf_conntrack_core.c-2069-\t\t\t dataoff, state-\u003epf, protonum, state-\u003enet,\n" }
47/3	2026/09/20 21:58	llm	kmsan-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 15100 output: 42 thoughts: 36 Thoughts: Here's my summary, as though I were thinking through the process: Diving into the Conntrack Core Alright, time to dig into `nf_ct_get_tuple`. Let's see what's going on at line 266 in `net/netfilter/nf_conntrack_core.c`. I need to refresh my memory on how the core conntrack functions are structured, especially how tuples are handled. Knowing the tuple data structures is critical to understanding connection tracking, and how packets are matched to existing connections. Hopefully, this routine gives me the necessary context. Time to trace this.
48/3	2026/09/20 21:58	tool	read-file	0m Args: { "File": "net/netfilter/nf_conntrack_core.c", "FirstLine": 266, "LineCount": 45 } Results: { "Contents": " 266:\tstatic bool\n 267:\tnf_ct_get_tuple(const struct sk_buff skb,\n 268:\t\t\tunsigned int nhoff,\n 269:\t\t\tunsigned int dataoff,\n 270:\t\t\tu_int16_t l3num,\n 271:\t\t\tu_int8_t protonum,\n 272:\t\t\tstruct net net,\n 273:\t\t\tstruct nf_conntrack_tuple tuple)\n 274:\t{\n 275:\t\tunsigned int size;\n 276:\t\tconst __be32 ap;\n 277:\t\t__be32 _addrs[8];\n 278:\t\n 279:\t\tmemset(tuple, 0, sizeof(tuple));\n 280:\t\n 281:\t\ttuple-\u003esrc.l3num = l3num;\n 282:\t\tswitch (l3num) {\n 283:\t\tcase NFPROTO_IPV4:\n 284:\t\t\tnhoff += offsetof(struct iphdr, saddr);\n 285:\t\t\tsize = 2 sizeof(__be32);\n 286:\t\t\tbreak;\n 287:\t\tcase NFPROTO_IPV6:\n 288:\t\t\tnhoff += offsetof(struct ipv6hdr, saddr);\n 289:\t\t\tsize = sizeof(_addrs);\n 290:\t\t\tbreak;\n 291:\t\tdefault:\n 292:\t\t\treturn true;\n 293:\t\t}\n 294:\t\n 295:\t\tap = skb_header_pointer(skb, nhoff, size, _addrs);\n 296:\t\tif (!ap)\n 297:\t\t\treturn false;\n 298:\t\n 299:\t\tswitch (l3num) {\n 300:\t\tcase NFPROTO_IPV4:\n 301:\t\t\ttuple-\u003esrc.u3.ip = ap[0];\n 302:\t\t\ttuple-\u003edst.u3.ip = ap[1];\n 303:\t\t\tbreak;\n 304:\t\tcase NFPROTO_IPV6:\n 305:\t\t\tmemcpy(tuple-\u003esrc.u3.ip6, ap, sizeof(tuple-\u003esrc.u3.ip6));\n 306:\t\t\tmemcpy(tuple-\u003edst.u3.ip6, ap + 4, sizeof(tuple-\u003edst.u3.ip6));\n 307:\t\t\tbreak;\n 308:\t\t}\n 309:\t\n 310:\t\ttuple-\u003edst.protonum = protonum;\n" }
49/3	2026/09/20 21:58	llm	kmsan-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 15973 output: 34 thoughts: 406 Thoughts: My Initial Thoughts on Zero-Initialization and Connection Tracking Okay, here's what's running through my head. I'm seeing `memset(tuple, 0, sizeof(*tuple));` right at the start of `nf_ct_get_tuple`. That's interesting, the zero-initialization. And, let's see, `nf_ct_invert_tuple` also calls `memset` on its `inverse` tuple. Noted. Now, let's look at `nft_ct.c`. This `nft_ct_get_safe` function is grabbing the connection and doing some sanity checks. It calls `nf_ct_get` and makes sure the L4 protocol matches what it expects. The checks for `IPS_TEMPLATE` and `IPS_CONFIRMED` are expected too. Looks good so far, standard connection tracking stuff. But wait a minute... I'm really curious about `nft_ct_expect_helper_alloc`. Specifically, I see `ct_expect_helper->l4proto = priv->l4proto;`. Before this commit, what would the value of `ct_expect_helper->l4proto` have been? Zero? Or uninitialized garbage? We need to go further to figure this out. I'm going to look into where `ct_expect_helper` is actually allocated! That's the key. I need to understand if the caller is responsible for setting `l4proto`, or if it was implicitly relying on the `memset` I saw earlier. We've got a potential initialization issue here that could lead to unexpected behavior.
50/3	2026/09/20 21:58	tool	grepper	0m Args: { "Expression": "nft_ct_expect_helper_alloc", "PathPrefix": "net/netfilter/" } Results: { "Output": "net/netfilter/nft_ct.c=1271=static int ct_expect_help(struct sk_buff skb, unsigned int protoff,\n--\nnet/netfilter/nft_ct.c-1319-\nnet/netfilter/nft_ct.c:1320:static int nft_ct_expect_helper_alloc(struct nft_ct_expect_obj priv)\nnet/netfilter/nft_ct.c-1321-{\n--\nnet/netfilter/nft_ct.c=1343=static int nft_ct_expect_obj_init(const struct nft_ctx *ctx,\n--\nnet/netfilter/nft_ct.c-1397-\nnet/netfilter/nft_ct.c:1398:\terr = nft_ct_expect_helper_alloc(priv);\nnet/netfilter/nft_ct.c-1399-\tif (err \u003c 0) {\n" }
51/3	2026/09/20 21:58	llm	kmsan-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 16999 output: 39 thoughts: 28 Thoughts: Here's my take on the process, playing the role you've specified: Diving into nft_ct_expect_helper_alloc Alright, let's get into the details of `nft_ct_expect_helper_alloc`, which lives right there in `net/netfilter/nft_ct.c`. I need to understand how this helper function allocates and manages resources, especially within the context of connection tracking in Netfilter. I'm already anticipating some of the nuances; I want to see how it handles memory allocation, error checking, and potential race conditions, especially given the kernel context. I expect this function is critical for managing state related to connection expectations, and I hope it's well-optimized for performance. I need to figure out exactly how it interfaces with other Netfilter components. Let's see what the code actually shows rather than what I assume.
52/3	2026/09/20 21:58	tool	read-file	0m Args: { "File": "net/netfilter/nft_ct.c", "FirstLine": 1315, "LineCount": 35 } Results: { "Contents": "1315:\t\tnf_ct_expect_put(exp);\n1316:\t\n1317:\t\treturn ret;\n1318:\t}\n1319:\t\n1320:\tstatic int nft_ct_expect_helper_alloc(struct nft_ct_expect_obj priv)\n1321:\t{\n1322:\t\tstruct nf_conntrack_helper ct_expect_helper;\n1323:\t\n1324:\t\tct_expect_helper = kzalloc_obj(struct nf_conntrack_helper,\n1325:\t\t\t\t\t GFP_KERNEL_ACCOUNT);\n1326:\t\tif (!ct_expect_helper)\n1327:\t\t\treturn -ENOMEM;\n1328:\t\n1329:\t\tsnprintf(ct_expect_helper-\u003ename, sizeof(ct_expect_helper-\u003ename), \"%s\",\n1330:\t\t\t \"nft_ct_expect\");\n1331:\t\tct_expect_helper-\u003eme = THIS_MODULE;\n1332:\t\tct_expect_helper-\u003eexpect_policy[NF_CT_EXPECT_CLASS_DEFAULT].max_expected = priv-\u003esize;\n1333:\t\tct_expect_helper-\u003el4proto = priv-\u003el4proto;\n1334:\t\trcu_assign_pointer(ct_expect_helper-\u003ehelp, ct_expect_help);\n1335:\t\trefcount_set(\u0026ct_expect_helper-\u003ect_refcnt, 1);\n1336:\t\n1337:\t\t/* No need to register this helper, this is internal. /\n1338:\t\tpriv-\u003ehelper = ct_expect_helper;\n1339:\t\n1340:\t\treturn 0;\n1341:\t}\n1342:\t\n1343:\tstatic int nft_ct_expect_obj_init(const struct nft_ctx ctx,\n1344:\t\t\t\t\t const struct nlattr * const tb[],\n1345:\t\t\t\t\t struct nft_object obj)\n1346:\t{\n1347:\t\tstruct nft_ct_expect_obj priv = nft_obj_data(obj);\n1348:\t\tint err;\n1349:\t\n" }
53/3	2026/09/20 21:58	llm	kmsan-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 17822 output: 31 thoughts: 1675 Thoughts: Analyzing Connection Tracking Data Structures Okay, so I'm digging into this connection tracking code. First, `kzalloc_obj` was used, which means the memory was zeroed initially. Then, `l4proto` is explicitly set, so that's handled. Now, let's look at `nf_ct_check_icmp_inner`. It's straightforward. It calls `nf_ct_get_tuplepr`. If that returns `false`, `tuple` isn't used, so no worries. If it returns `true`, we know `tuple` has been initialized because the function calls `nf_ct_get_tuple` which zero initializes it. So, `tuple` is always initialized. Got it. Next up, `nf_ct_get_careful`. Here, `tuple` is initialized by `nf_ct_get_tuple`. The `inverse` tuple is initialized using `nf_ct_invert_tuple`, and `dir` comes from `*ctinfo`. So, all of those are explicitly initialized before they're used. Everything's accounted for. Now, let's investigate `nf_confirm_get_protoff`. I see a couple of things here that are worth extra attention. In the IPv4 case, we're checking for fragmentation. In the IPv6 case, we have `start = ipv6_skip_exthdr(skb, nhoff + sizeof(struct ipv6hdr), pnum, &frag_off);`. I need to review how that `ipv6_skip_exthdr` works to make sure there are no issues. It seems like it may play a critical role here.
54/3	2026/09/20 21:59	tool	grepper	0m Args: { "Expression": "ipv6_skip_exthdr\\(", "PathPrefix": "net/" } Results: { "Output": "net/bridge/netfilter/ebt_ip6.c=38=ebt_ip6_mt(const struct sk_buff skb, struct xt_action_param par)\n--\nnet/bridge/netfilter/ebt_ip6.c-66-\nnet/bridge/netfilter/ebt_ip6.c:67:\t\toffset_ph = ipv6_skip_exthdr(skb, sizeof(_ip6h), \u0026nexthdr, \u0026frag_off);\nnet/bridge/netfilter/ebt_ip6.c-68-\t\tif (offset_ph == -1)\n--\nnet/bridge/netfilter/ebt_log.c=74=ebt_log_packet(struct net net, u_int8_t pf, unsigned int hooknum,\n--\nnet/bridge/netfilter/ebt_log.c-129-\t\tnexthdr = ih-\u003enexthdr;\nnet/bridge/netfilter/ebt_log.c:130:\t\toffset_ph = ipv6_skip_exthdr(skb, sizeof(_iph), \u0026nexthdr, \u0026frag_off);\nnet/bridge/netfilter/ebt_log.c-131-\t\tif (offset_ph == -1)\n--\nnet/ipv4/esp4_offload.c=149=static struct sk_buff xfrm4_beet_gso_segment(struct xfrm_state x,\n--\nnet/ipv4/esp4_offload.c-173-\t\tskb-\u003etransport_header +=\nnet/ipv4/esp4_offload.c:174:\t\t\tipv6_skip_exthdr(skb, 0, \u0026proto, \u0026frag);\nnet/ipv4/esp4_offload.c-175-\t\tif (proto == IPPROTO_TCP)\n--\nnet/ipv4/ip_tunnel_core.c=390=static int iptunnel_pmtud_check_icmpv6(struct sk_buff skb, int mtu)\n--\nnet/ipv4/ip_tunnel_core.c-404-\nnet/ipv4/ip_tunnel_core.c:405:\toffset = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), \u0026proto,\nnet/ipv4/ip_tunnel_core.c-406-\t\t\t\t \u0026frag_off);\n--\nnet/ipv6/esp6.c=746=int esp6_input_done2(struct sk_buff skb, int err)\n--\nnet/ipv6/esp6.c-772-\nnet/ipv6/esp6.c:773:\t\toffset = ipv6_skip_exthdr(skb, offset, \u0026nexthdr, \u0026frag_off);\nnet/ipv6/esp6.c-774-\t\tif (offset == -1) {\n--\nnet/ipv6/esp6_offload.c=133=static void esp6_gso_encap(struct xfrm_state x, struct sk_buff skb)\n--\nnet/ipv6/esp6_offload.c-144-\nnet/ipv6/esp6_offload.c:145:\t\tipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), \u0026proto, \u0026frag);\nnet/ipv6/esp6_offload.c-146-\t}\n--\nnet/ipv6/esp6_offload.c=185=static struct sk_buff xfrm6_beet_gso_segment(struct xfrm_state x,\n--\nnet/ipv6/esp6_offload.c-215-\t\tskb-\u003etransport_header +=\nnet/ipv6/esp6_offload.c:216:\t\t\tipv6_skip_exthdr(skb, 0, \u0026proto, \u0026frag);\nnet/ipv6/esp6_offload.c-217-\t}\n--\nnet/ipv6/exthdrs_core.c=25=EXPORT_SYMBOL(ipv6_ext_hdr);\n--\nnet/ipv6/exthdrs_core.c-71-\nnet/ipv6/exthdrs_core.c:72:int ipv6_skip_exthdr(const struct sk_buff skb, int start, u8 nexthdrp,\nnet/ipv6/exthdrs_core.c-73-\t\t __be16 frag_offp)\n--\nnet/ipv6/icmp.c=136=static bool is_ineligible(const struct sk_buff skb)\n--\nnet/ipv6/icmp.c-145-\nnet/ipv6/icmp.c:146:\tptr = ipv6_skip_exthdr(skb, ptr, \u0026nexthdr, \u0026frag_off);\nnet/ipv6/icmp.c-147-\tif (ptr \u003c 0)\n--\nnet/ipv6/icmp.c=1037=enum skb_drop_reason icmpv6_notify(struct sk_buff skb, u8 type,\n--\nnet/ipv6/icmp.c-1056-\t\t/* now skip over extension headers /\nnet/ipv6/icmp.c:1057:\t\tinner_offset = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr),\nnet/ipv6/icmp.c-1058-\t\t\t\t\t\t\u0026nexthdr, \u0026frag_off);\n--\nnet/ipv6/ip6_input.c=554=int ip6_mc_input(struct sk_buff skb)\n--\nnet/ipv6/ip6_input.c-608-\t\t\t\t}\nnet/ipv6/ip6_input.c:609:\t\t\t\toffset = ipv6_skip_exthdr(skb, sizeof(hdr),\nnet/ipv6/ip6_input.c-610-\t\t\t\t\t\t\t \u0026nexthdr, \u0026frag_off);\n--\nnet/ipv6/ip6_output.c=436=static int ip6_forward_proxy_check(struct sk_buff skb)\n--\nnet/ipv6/ip6_output.c-443-\tif (ipv6_ext_hdr(nexthdr)) {\nnet/ipv6/ip6_output.c:444:\t\toffset = ipv6_skip_exthdr(skb, sizeof(hdr), \u0026nexthdr, \u0026frag_off);\nnet/ipv6/ip6_output.c-445-\t\tif (offset \u003c 0)\n--\nnet/ipv6/mcast_snoop.c=37=static int ipv6_mc_check_exthdrs(struct sk_buff skb)\n--\nnet/ipv6/mcast_snoop.c-50-\toffset = skb_network_offset(skb) + sizeof(ip6h);\nnet/ipv6/mcast_snoop.c:51:\toffset = ipv6_skip_exthdr(skb, offset, \u0026nexthdr, \u0026frag_off);\nnet/ipv6/mcast_snoop.c-52-\n--\nnet/ipv6/netfilter/nf_reject_ipv6.c=29=static bool nf_reject_v6_csum_ok(struct sk_buff skb, int hook)\n--\nnet/ipv6/netfilter/nf_reject_ipv6.c-43-\tip6h = ipv6_hdr(skb);\nnet/ipv6/netfilter/nf_reject_ipv6.c:44:\tthoff = ipv6_skip_exthdr(skb, ((u8)(ip6h+1) - skb-\u003edata), \u0026proto, \u0026fo);\nnet/ipv6/netfilter/nf_reject_ipv6.c-45-\tif (thoff \u003c 0 \|\| thoff \u003e= skb-\u003elen \|\| (fo \u0026 htons(~0x7)) != 0)\n--\nnet/ipv6/netfilter/nf_reject_ipv6.c=108=static bool nf_skb_is_icmp6_unreach(const struct sk_buff skb)\n--\nnet/ipv6/netfilter/nf_reject_ipv6.c-115-\nnet/ipv6/netfilter/nf_reject_ipv6.c:116:\tthoff = ipv6_skip_exthdr(skb, ((u8 )(ip6h + 1) - skb-\u003edata), \u0026proto, \u0026fo);\nnet/ipv6/netfilter/nf_reject_ipv6.c-117-\n--\nnet/ipv6/netfilter/nf_reject_ipv6.c=194=nf_reject_ip6_tcphdr_get(struct sk_buff oldskb,\n--\nnet/ipv6/netfilter/nf_reject_ipv6.c-203-\tproto = oip6h-\u003enexthdr;\nnet/ipv6/netfilter/nf_reject_ipv6.c:204:\ttcphoff = ipv6_skip_exthdr(oldskb, ((u8 )(oip6h + 1) - oldskb-\u003edata),\nnet/ipv6/netfilter/nf_reject_ipv6.c-205-\t\t\t\t \u0026proto, \u0026frag_off);\n--\nnet/ipv6/netfilter/nf_reject_ipv6.c=416=static bool reject6_csum_ok(struct sk_buff skb, int hook)\n--\nnet/ipv6/netfilter/nf_reject_ipv6.c-426-\tproto = ip6h-\u003enexthdr;\nnet/ipv6/netfilter/nf_reject_ipv6.c:427:\tthoff = ipv6_skip_exthdr(skb, ((u8 )(ip6h + 1) - skb-\u003edata), \u0026proto, \u0026fo);\nnet/ipv6/netfilter/nf_reject_ipv6.c-428-\n--\nnet/ipv6/netfilter/nf_socket_ipv6.c=21=extract_icmp6_fields(const struct sk_buff skb,\n--\nnet/ipv6/netfilter/nf_socket_ipv6.c-50-\nnet/ipv6/netfilter/nf_socket_ipv6.c:51:\tinside_hdrlen = ipv6_skip_exthdr(skb, outside_hdrlen + sizeof(_icmph) +\nnet/ipv6/netfilter/nf_socket_ipv6.c-52-\t\t\t\t\t sizeof(ipv6_var),\n--\nnet/netfilter/ipset/ip_set_getport.c=132=ip_set_get_ip6_port(const struct sk_buff skb, bool src,\n--\nnet/netfilter/ipset/ip_set_getport.c-139-\tnexthdr = ipv6_hdr(skb)-\u003enexthdr;\nnet/netfilter/ipset/ip_set_getport.c:140:\tprotoff = ipv6_skip_exthdr(skb,\nnet/netfilter/ipset/ip_set_getport.c-141-\t\t\t\t skb_network_offset(skb) +\n--\nnet/netfilter/nf_conntrack_core.c=368=static int ipv6_get_l4proto(const struct sk_buff skb, unsigned int nhoff,\n--\nnet/netfilter/nf_conntrack_core.c-380-\t}\nnet/netfilter/nf_conntrack_core.c:381:\tprotoff = ipv6_skip_exthdr(skb, extoff, \u0026nexthdr, \u0026frag_off);\nnet/netfilter/nf_conntrack_core.c-382-\t/\n--\nnet/netfilter/nf_conntrack_core.c=2299=static int nf_confirm_cthelper(struct sk_buff skb, struct nf_conn ct,\n--\nnet/netfilter/nf_conntrack_core.c-2328-\t\tpnum = ipv6_hdr(skb)-\u003enexthdr;\nnet/netfilter/nf_conntrack_core.c:2329:\t\tprotoff = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), \u0026pnum,\nnet/netfilter/nf_conntrack_core.c-2330-\t\t\t\t\t \u0026frag_off);\n--\nnet/netfilter/nf_conntrack_proto.c=134=static bool nf_confirm_get_protoff(struct sk_buff skb, struct net net,\n--\nnet/netfilter/nf_conntrack_proto.c-154-\t\tpnum = ipv6_hdr(skb)-\u003enexthdr;\nnet/netfilter/nf_conntrack_proto.c:155:\t\tstart = ipv6_skip_exthdr(skb, nhoff + sizeof(struct ipv6hdr),\nnet/netfilter/nf_conntrack_proto.c-156-\t\t\t\t\t pnum, \u0026frag_off);\n--\nnet/netfilter/nf_nat_ovs.c=13=static int nf_ct_nat_execute(struct sk_buff skb, struct nf_conn ct,\n--\nnet/netfilter/nf_nat_ovs.c-38-\t\t\tu8 nexthdr = ipv6_hdr(skb)-\u003enexthdr;\nnet/netfilter/nf_nat_ovs.c:39:\t\t\tint hdrlen = ipv6_skip_exthdr(skb,\nnet/netfilter/nf_nat_ovs.c-40-\t\t\t\t\t\t sizeof(struct ipv6hdr),\n--\nnet/netfilter/nf_nat_proto.c=319=static bool nf_nat_ipv6_manip_pkt(struct sk_buff skb,\n--\nnet/netfilter/nf_nat_proto.c-334-\tnexthdr = ipv6h-\u003enexthdr;\nnet/netfilter/nf_nat_proto.c:335:\thdroff = ipv6_skip_exthdr(skb, iphdroff + sizeof(ipv6h),\nnet/netfilter/nf_nat_proto.c-336-\t\t\t\t \u0026nexthdr, \u0026frag_off);\n--\nnet/netfilter/nf_nat_proto.c=883=nf_nat_ipv6_fn(void priv, struct sk_buff skb,\n--\nnet/netfilter/nf_nat_proto.c-902-\t\tnexthdr = ipv6_hdr(skb)-\u003enexthdr;\nnet/netfilter/nf_nat_proto.c:903:\t\thdrlen = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr),\nnet/netfilter/nf_nat_proto.c-904-\t\t\t\t\t \u0026nexthdr, \u0026frag_off);\n--\nnet/netfilter/nf_synproxy_core.c=1066=ipv6_synproxy_hook(void priv, struct sk_buff skb,\n--\nnet/netfilter/nf_synproxy_core.c-1092-\tnexthdr = ipv6_hdr(skb)-\u003enexthdr;\nnet/netfilter/nf_synproxy_core.c:1093:\tthoff = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), \u0026nexthdr,\nnet/netfilter/nf_synproxy_core.c-1094-\t\t\t\t \u0026frag_off);\n--\nnet/netfilter/xt_TCPMSS.c=219=tcpmss_tg6(struct sk_buff skb, const struct xt_action_param par)\n--\nnet/netfilter/xt_TCPMSS.c-227-\tnexthdr = ipv6h-\u003enexthdr;\nnet/netfilter/xt_TCPMSS.c:228:\ttcphoff = ipv6_skip_exthdr(skb, sizeof(ipv6h), \u0026nexthdr, \u0026frag_off);\nnet/netfilter/xt_TCPMSS.c-229-\tif (tcphoff \u003c 0)\n--\nnet/netfilter/xt_TCPOPTSTRIP.c=96=tcpoptstrip_tg6(struct sk_buff skb, const struct xt_action_param par)\n--\nnet/netfilter/xt_TCPOPTSTRIP.c-103-\tnexthdr = ipv6h-\u003enexthdr;\nnet/netfilter/xt_TCPOPTSTRIP.c:104:\ttcphoff = ipv6_skip_exthdr(skb, sizeof(ipv6h), \u0026nexthdr, \u0026frag_off);\nnet/netfilter/xt_TCPOPTSTRIP.c-105-\tif (tcphoff \u003c 0)\n--\nnet/netfilter/xt_hashlimit.c=641=hashlimit_init_dst(const struct xt_hashlimit_htable hinfo,\n--\nnet/netfilter/xt_hashlimit.c-686-\t\tnexthdr = ipv6_hdr(skb)-\u003enexthdr;\nnet/netfilter/xt_hashlimit.c:687:\t\tprotoff = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), \u0026nexthdr, \u0026frag_off);\nnet/netfilter/xt_hashlimit.c-688-\t\tif ((int)protoff \u003c 0 \|\| ntohs(frag_off) \u0026 IP6_OFFSET)\n" }
55/3	2026/09/20 21:59	llm	kmsan-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 24168 output: 40 thoughts: 19 Thoughts: Okay, here's my take on those thoughts, tailored for an expert audience: Diving into `ipv6_skip_exthdr` for a Close Look Right, let's get down to brass tacks and really dig into this `ipv6_skip_exthdr` implementation. My initial concern is always robustness and subtle corner cases. I want to scrutinize the code, assuming the worst-case scenario. This means checking for all possible extension headers, ensuring proper handling of chained headers, and verifying the logic handles malformed packets gracefully. I'm thinking about the potential for fragmentation issues, reassembly complexity, and any vulnerabilities that might be lurking within the header parsing. I'll need to check the data structure alignment and memory handling. I'll look for potential integer overflows and underflows when calculating lengths and offsets. I'll want to trace its use across the system, to verify it's utilized as intended. It is possible this is not the right place to start; however, let's keep it in mind. Let's see what we can find.
56/3	2026/09/20 21:59	tool	read-file	0m Args: { "File": "net/ipv6/exthdrs_core.c", "FirstLine": 71, "LineCount": 45 } Results: { "Contents": " 71:\t\n 72:\tint ipv6_skip_exthdr(const struct sk_buff skb, int start, u8 nexthdrp,\n 73:\t\t\t __be16 frag_offp)\n 74:\t{\n 75:\t\tu8 nexthdr = nexthdrp;\n 76:\t\tint exthdr_cnt = 0;\n 77:\t\n 78:\t\tfrag_offp = 0;\n 79:\t\n 80:\t\twhile (ipv6_ext_hdr(nexthdr)) {\n 81:\t\t\tstruct ipv6_opt_hdr _hdr, hp;\n 82:\t\t\tint hdrlen;\n 83:\t\n 84:\t\t\tif (nexthdr == NEXTHDR_NONE)\n 85:\t\t\t\treturn -1;\n 86:\t\t\tif (unlikely(exthdr_cnt++ \u003e= IP6_MAX_EXT_HDRS_CNT))\n 87:\t\t\t\treturn -1;\n 88:\t\t\thp = skb_header_pointer(skb, start, sizeof(_hdr), \u0026_hdr);\n 89:\t\t\tif (!hp)\n 90:\t\t\t\treturn -1;\n 91:\t\t\tif (nexthdr == NEXTHDR_FRAGMENT) {\n 92:\t\t\t\t__be16 _frag_off, fp;\n 93:\t\t\t\tfp = skb_header_pointer(skb,\n 94:\t\t\t\t\t\t\tstart+offsetof(struct frag_hdr,\n 95:\t\t\t\t\t\t\t\t frag_off),\n 96:\t\t\t\t\t\t\tsizeof(_frag_off),\n 97:\t\t\t\t\t\t\t\u0026_frag_off);\n 98:\t\t\t\tif (!fp)\n 99:\t\t\t\t\treturn -1;\n 100:\t\n 101:\t\t\t\tfrag_offp = fp;\n 102:\t\t\t\tif (ntohs(frag_offp) \u0026 ~0x7)\n 103:\t\t\t\t\tbreak;\n 104:\t\t\t\thdrlen = 8;\n 105:\t\t\t} else if (nexthdr == NEXTHDR_AUTH)\n 106:\t\t\t\thdrlen = ipv6_authlen(hp);\n 107:\t\t\telse\n 108:\t\t\t\thdrlen = ipv6_optlen(hp);\n 109:\t\n 110:\t\t\tnexthdr = hp-\u003enexthdr;\n 111:\t\t\tstart += hdrlen;\n 112:\t\t}\n 113:\t\n 114:\t\t*nexthdrp = nexthdr;\n 115:\t\treturn start;\n" }
57/3	2026/09/20 21:59	llm	kmsan-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 25104 output: 27 thoughts: 1041 Thoughts: Analyzing Potential Conntrack Vulnerability Okay, let's break this down. My initial observation is focused on how IPv6 extension headers are handled, specifically within `ipv6_skip_exthdr`. It's clear that it initializes the `frag_offp` to zero and updates `*nexthdrp`. Now, the important point is that the inputs passed to `ipv6_skip_exthdr` in `nf_confirm_get_protoff` are all initialized, which should be fine. Next, I'm examining how TCP headers are dealt with. `skb_header_pointer` is used to access the TCP header. It either reads data into a local `_tcph` or returns a pointer to the SKB data. Critically, if the packet doesn't contain at least `sizeof(_tcph)` bytes at the given offset (`protoff`), `skb_header_pointer` returns `NULL`. This suggests a potential area where insufficient length checks could lead to problems. Now, focusing on the broader conntrack code in `nf_conntrack_proto.c` and specifically `nf_conntrack_in`. This is where it gets interesting, and I'm starting to see a possible vulnerability. The `get_l4proto` function determines the L4 protocol and offset. Crucially, the code calls `nf_ct_get_careful`. I was curious about what happens if `tmpl` is NULL when `tmpl = nf_ct_get_careful(skb, state, dataoff, protonum, &ctinfo);` This could be the source of a potential issue. Now let's compare before and after the change that added `get_l4proto`. Before, the code directly called `nf_ct_get`. Now, `nf_ct_get_careful` is used. Inside `nf_ct_get_careful`, it calls `nf_ct_get`, where `!tmpl` causes `nf_ct_get` to write into `ctinfo`. Let me check if `nf_ct_get(skb, ctinfo)` is called when `tmpl == NULL` to verify how `ctinfo` is updated when `tmpl` is NULL. I need to examine `nf_ct_get` itself to understand how this interaction works in detail.
58/3	2026/09/20 21:59	tool	grepper	0m Error: no matches Args: { "Expression": "static inline struct nf_conn \\nf_ct_get\\(" } Results:* { "error": "no matches" }
59/3	2026/09/20 21:59	llm	kmsan-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 26689 output: 25 thoughts: 14 Thoughts: Here's my thought process, as if I were thinking it: Digging into the `nf_ct_get(` Function Alright, time to dive in. My immediate thought is, "Where's the definition for `nf_ct_get(`?" I need to understand exactly what this function does. Its behavior is critical for whatever I'm troubleshooting or analyzing right now. Let's get to the source code, see what headers are included, and figure out its dependencies. I'm hoping it's well-commented, of course, but even if not, I can unravel it. This function is likely central to the connection tracking mechanism, so I'm expecting some interactions with Netfilter's core data structures and likely some locking. I'll need to keep an eye out for potential concurrency issues or subtle race conditions within its implementation, especially if it's operating at the kernel level. Let's get to it!
60/3	2026/09/20 21:59	tool	grepper	0m Args: { "Expression": "nf_ct_get\\(const struct sk_buff" } Results: { "Output": "include/net/netfilter/nf_conntrack.h=168=static inline struct nf_conn \ninclude/net/netfilter/nf_conntrack.h:169:nf_ct_get(const struct sk_buff skb, enum ip_conntrack_info *ctinfo)\ninclude/net/netfilter/nf_conntrack.h-170-{\n" }
61/3	2026/09/20 21:59	llm	kmsan-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 27033 output: 42 thoughts: 28 Thoughts: Here's my summary, as though I'm reading and processing the provided text: Diving into the Connection Tracking Core Okay, time to get my hands dirty. I'm going to start by taking a close look at `nf_ct_get`. Let's navigate to the definition in `include/net/netfilter/nf_conntrack.h`. This is where the heart of connection tracking for Netfilter should reside. This function, `nf_ct_get`, is the workhorse. I'll bet it's responsible for retrieving existing conntrack entries or handling the initial lookup. I need to understand its exact behavior to analyze the overall flow. Knowing this is crucial for the task at hand.
62/3	2026/09/20 21:59	tool	read-file	0m Args: { "File": "include/net/netfilter/nf_conntrack.h", "FirstLine": 168, "LineCount": 20 } Results: { "Contents": " 168:\tstatic inline struct nf_conn \n 169:\tnf_ct_get(const struct sk_buff skb, enum ip_conntrack_info ctinfo)\n 170:\t{\n 171:\t\tunsigned long nfct = skb_get_nfct(skb);\n 172:\t\n 173:\t\tctinfo = nfct \u0026 NFCT_INFOMASK;\n 174:\t\treturn (struct nf_conn )(nfct \u0026 NFCT_PTRMASK);\n 175:\t}\n 176:\t\n 177:\tvoid nf_ct_destroy(struct nf_conntrack nfct);\n 178:\t\n 179:\tvoid nf_conntrack_tcp_set_closing(struct nf_conn ct);\n 180:\t\n 181:\t/ decrement reference count on a conntrack /\n 182:\tstatic inline void nf_ct_put(struct nf_conn ct)\n 183:\t{\n 184:\t\tif (ct \u0026\u0026 refcount_dec_and_test(\u0026ct-\u003ect_general.use))\n 185:\t\t\tnf_ct_destroy(\u0026ct-\u003ect_general);\n 186:\t}\n 187:\t\n" }
63/3	2026/09/20 21:59	llm	kmsan-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 27591 output: 32 thoughts: 449 Thoughts: Conntrack Info Mysteries Okay, so I'm digging into this conntrack code, and something's bugging me. It seems that `*ctinfo = nfct & NFCT_INFOMASK;` is always set, even if `nfct` is zero. That seems straightforward enough, but it has some implications down the line. Specifically, I'm focusing on the `nf_ct_get_careful` function. It looks like it retrieves a connection template. If we get a `tmpl` back, great. We can return it if the hook is `NF_INET_LOCAL_OUT` or if it's a template. But if there's an error, and the code jumps to that `error:` label, the function `nf_reset_ct(skb);` is called, and then NULL is returned. Here's the problem: later, in `nf_conntrack_in`, `nf_ct_get_careful` is called again. The critical part is this conditional: `if (tmpl \|\| ctinfo == IP_CT_UNTRACKED)`. If `error:` was hit, then `tmpl` is NULL. But what is `ctinfo` then? `nf_ct_get(skb, ctinfo)` had already set `ctinfo` before jumping to `error:`! I'm trying to figure out the possible values for `ctinfo`. It looks like `ctinfo` could equal `IP_CT_UNTRACKED` if `tmpl` was valid and not a template, but then reset by `nf_reset_ct(skb)`. This feels odd, so I'm going to track down where `IP_CT_UNTRACKED` is used and see what other values are possible for `ctinfo`.
64/3	2026/09/20 21:59	tool	grepper	0m Args: { "Expression": "IP_CT_UNTRACKED", "PathPrefix": "net/netfilter/" } Results: { "Output": "net/netfilter/nf_conntrack_core.c=2098=nf_conntrack_in(struct sk_buff skb, const struct nf_hook_state state)\n--\nnet/netfilter/nf_conntrack_core.c-2109-\t\ttmpl = nf_ct_get(skb, \u0026ctinfo);\nnet/netfilter/nf_conntrack_core.c:2110:\t\tif (ctinfo != IP_CT_UNTRACKED)\nnet/netfilter/nf_conntrack_core.c-2111-\t\t\tnf_reset_ct(skb);\n--\nnet/netfilter/nf_conntrack_core.c-2115-\ttmpl = nf_ct_get_careful(skb, state, dataoff, protonum, \u0026ctinfo);\nnet/netfilter/nf_conntrack_core.c:2116:\tif (tmpl \|\| ctinfo == IP_CT_UNTRACKED) {\nnet/netfilter/nf_conntrack_core.c-2117-\t\t/* Previously seen (loopback or untracked)? Ignore. /\nnet/netfilter/nf_conntrack_core.c-2118-\t\tif ((tmpl \u0026\u0026 !nf_ct_is_template(tmpl)) \|\|\nnet/netfilter/nf_conntrack_core.c:2119:\t\t ctinfo == IP_CT_UNTRACKED)\nnet/netfilter/nf_conntrack_core.c-2120-\t\t\treturn NF_ACCEPT;\n--\nnet/netfilter/nf_conntrack_core.c=2835=int nf_conntrack_init_net(struct net net)\n--\nnet/netfilter/nf_conntrack_core.c-2839-\nnet/netfilter/nf_conntrack_core.c:2840:\tBUILD_BUG_ON(IP_CT_UNTRACKED == IP_CT_NUMBER);\nnet/netfilter/nf_conntrack_core.c-2841-\tBUILD_BUG_ON_NOT_POWER_OF_2(CONNTRACK_LOCKS);\n--\nnet/netfilter/nf_conntrack_proto_icmpv6.c=184=int nf_conntrack_icmpv6_error(struct nf_conn tmpl,\n--\nnet/netfilter/nf_conntrack_proto_icmpv6.c-209-\t noct_valid_new[type]) {\nnet/netfilter/nf_conntrack_proto_icmpv6.c:210:\t\tnf_ct_set(skb, NULL, IP_CT_UNTRACKED);\nnet/netfilter/nf_conntrack_proto_icmpv6.c-211-\t\treturn NF_ACCEPT;\n--\nnet/netfilter/nf_tables_trace.c=94=static int nf_trace_fill_ct_info(struct sk_buff nlskb,\n--\nnet/netfilter/nf_tables_trace.c-107-\tif (!ct) {\nnet/netfilter/nf_tables_trace.c:108:\t\tif (ctinfo != IP_CT_UNTRACKED) /* not seen by conntrack or invalid /\nnet/netfilter/nf_tables_trace.c-109-\t\t\treturn 0;\n--\nnet/netfilter/nft_ct.c=52=static void nft_ct_get_eval(const struct nft_expr expr,\n--\nnet/netfilter/nft_ct.c-70-\t\t\tstate = NF_CT_STATE_BIT(ctinfo);\nnet/netfilter/nft_ct.c:71:\t\telse if (ctinfo == IP_CT_UNTRACKED)\nnet/netfilter/nft_ct.c-72-\t\t\tstate = NF_CT_STATE_UNTRACKED_BIT;\n--\nnet/netfilter/nft_ct.c=813=static void nft_notrack_eval(const struct nft_expr expr,\n--\nnet/netfilter/nft_ct.c-822-\t/ Previously seen (loopback or untracked)? Ignore. /\nnet/netfilter/nft_ct.c:823:\tif (ct \|\| ctinfo == IP_CT_UNTRACKED)\nnet/netfilter/nft_ct.c-824-\t\treturn;\nnet/netfilter/nft_ct.c-825-\nnet/netfilter/nft_ct.c:826:\tnf_ct_set(skb, ct, IP_CT_UNTRACKED);\nnet/netfilter/nft_ct.c-827-}\n--\nnet/netfilter/nft_ct_fast.c=7=void nft_ct_get_fast_eval(const struct nft_expr expr,\n--\nnet/netfilter/nft_ct_fast.c-22-\t\t\tstate = NF_CT_STATE_BIT(ctinfo);\nnet/netfilter/nft_ct_fast.c:23:\t\telse if (ctinfo == IP_CT_UNTRACKED)\nnet/netfilter/nft_ct_fast.c-24-\t\t\tstate = NF_CT_STATE_UNTRACKED_BIT;\n--\nnet/netfilter/xt_CT.c=21=static inline int xt_ct_target(struct sk_buff skb, struct nf_conn ct)\n--\nnet/netfilter/xt_CT.c-30-\t} else {\nnet/netfilter/xt_CT.c:31:\t\tnf_ct_set(skb, ct, IP_CT_UNTRACKED);\nnet/netfilter/xt_CT.c-32-\t}\n--\nnet/netfilter/xt_CT.c=318=notrack_tg(struct sk_buff skb, const struct xt_action_param par)\n--\nnet/netfilter/xt_CT.c-323-\nnet/netfilter/xt_CT.c:324:\tnf_ct_set(skb, NULL, IP_CT_UNTRACKED);\nnet/netfilter/xt_CT.c-325-\n--\nnet/netfilter/xt_conntrack.c=162=conntrack_mt(const struct sk_buff skb, struct xt_action_param par,\n--\nnet/netfilter/xt_conntrack.c-173-\t\tstatebit = XT_CONNTRACK_STATE_BIT(ctinfo);\nnet/netfilter/xt_conntrack.c:174:\telse if (ctinfo == IP_CT_UNTRACKED)\nnet/netfilter/xt_conntrack.c-175-\t\tstatebit = XT_CONNTRACK_STATE_UNTRACKED;\n--\nnet/netfilter/xt_state.c=21=state_mt(const struct sk_buff skb, struct xt_action_param par)\n--\nnet/netfilter/xt_state.c-29-\t\tstatebit = XT_STATE_BIT(ctinfo);\nnet/netfilter/xt_state.c:30:\telse if (ctinfo == IP_CT_UNTRACKED)\nnet/netfilter/xt_state.c-31-\t\tstatebit = XT_STATE_UNTRACKED;\n" }
65/3	2026/09/20 21:59	llm	kmsan-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 30228 output: 344 thoughts: 3552 Thoughts: Analysis of Potential Uninitialized Memory Issues Alright, let's break down this patch and see if we have any KMSAN concerns. My initial thought process revolves around ensuring we haven't introduced any vulnerabilities related to uninitialized memory. Given my expertise in this area, the primary focus is to methodically examine each variable and code path to confirm there aren't any potential information leaks or other memory safety issues. First, I need to understand when `ctinfo` might hold `IP_CT_UNTRACKED` and how that interacts with `nf_ct_get_careful`. If `tmpl` is NULL because `ctinfo` is `IP_CT_UNTRACKED`, does the early return in `nf_ct_get_careful` bypass crucial initialization? It doesn't appear so; `nf_ct_get` always seems to set `ctinfo` before it's used, even if the conntrack entry is untracked. Okay, now let's apply the KMSAN criteria. Does this patch involve: 1) structures sent to user space? Nope. 2) conditional logic based on potentially uninitialized variables? Let's trace all of the variables that might fit this category: 1. `nf_ct_check_icmp_inner`: `tuple` is initialized either by `nf_ct_get_tuplepr` and populated by `memset` by the inner function, or never read. 2. `nf_ct_get_careful`: `ctinfo` is definitely written by `nf_ct_get`; `tuple` and `inverse` get zeroed by `memset` if their respective calls succeed. `dir` is initialized by `CTINFO2DIR`. 3. `nf_conntrack_in`: `protonum` is set by `get_l4proto` or never used if the return value is not valid. `ctinfo` is set via the same patterns as above. 4. `nf_confirm_get_protoff`: Inside `nf_confirm_get_protoff`, variables `pnum`, `protoff`, `frag_off`, `tuple`, and `invert` are all initialized either by direct assignment, function calls, or by `memset`. Importantly, `_tcph` is always fully initialized if accessed. The code performs numerous length and bounds checks to protect against accessing invalid packet data, too. 5. `nf_ct_call_helper`: `pnum` is initialized to 0, `protoff` is conditionally set (only read if `nf_confirm_get_protoff` returns true). 6. `nft_ct_get_safe`: `ctinfo` is set via `nf_ct_get`. 7. `nft_ct_expect_helper_alloc`: `l4proto` is explicitly initialized. 3) allocation of complex data structures with uninitialized fields? Looks like everything is initialized! 4) bounds checks? The patch adds more checks that prevent accesses to uninitialized bytes. So, it seems we have a clean bill of health. I'm not seeing any cases where uninitialized memory could be read or leaked. All variables are either initialized before use (via direct assignment, `memset`, or by function calls), or they are not read if they are not initialized. My conclusion: KASAN and other standard detectors should be sufficient. KMSAN isn't needed here. Time to submit the assessment.
66/3	2026/09/20 21:59	tool	set-results	0m Args: { "KMSANReasoning": "The patch series addresses protocol revalidation in netfilter conntrack (adding `nf_ct_get_careful`, `nf_confirm_get_protoff`, and safe helpers) to prevent mismatched conntrack state when packets are mangled earlier in the network pipeline (e.g., via TC pedit).\n\nNone of the changes introduce uninitialized memory risks:\n1. No kernel structures or data are copied to userspace (no `copy_to_user`, netlink attributes, socket options, or ioctl responses modified).\n2. All local stack variables and tuples (`tuple`, `inverse`, `pnum`, `protonum`, `ctinfo`) are either explicitly initialized, zeroed with `memset` (e.g. within `nf_ct_get_tuple` and `nf_ct_invert_tuple`), or populated by their respective accessor functions before being read in conditional logic.\n3. Heap allocations modified (`kzalloc_obj` in `nft_ct_expect_helper_alloc`) already use zero-initialization, and the added field `l4proto` is explicitly set.\n4. The added bounds and header checks (e.g., verifying `protoff` and TCP header `doff` bounds in `nf_confirm_get_protoff`) prevent out-of-bounds reads and protocol misinterpretations, which are handled by KASAN rather than KMSAN.\n\nTherefore, standard KASAN fuzzing is fully sufficient and a dedicated KMSAN session is not justified.", "NeedsKMSAN": false } Results: { "KMSANReasoning": "The patch series addresses protocol revalidation in netfilter conntrack (adding `nf_ct_get_careful`, `nf_confirm_get_protoff`, and safe helpers) to prevent mismatched conntrack state when packets are mangled earlier in the network pipeline (e.g., via TC pedit).\n\nNone of the changes introduce uninitialized memory risks:\n1. No kernel structures or data are copied to userspace (no `copy_to_user`, netlink attributes, socket options, or ioctl responses modified).\n2. All local stack variables and tuples (`tuple`, `inverse`, `pnum`, `protonum`, `ctinfo`) are either explicitly initialized, zeroed with `memset` (e.g. within `nf_ct_get_tuple` and `nf_ct_invert_tuple`), or populated by their respective accessor functions before being read in conditional logic.\n3. Heap allocations modified (`kzalloc_obj` in `nft_ct_expect_helper_alloc`) already use zero-initialization, and the added field `l4proto` is explicitly set.\n4. The added bounds and header checks (e.g., verifying `protoff` and TCP header `doff` bounds in `nf_confirm_get_protoff`) prevent out-of-bounds reads and protocol misinterpretations, which are handled by KASAN rather than KMSAN.\n\nTherefore, standard KASAN fuzzing is fully sufficient and a dedicated KMSAN session is not justified.", "NeedsKMSAN": false }

LLM Calls Summary:
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Tool Calls Summary:
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