AI Trajectory

Trajectory: (Expand/Collapse All)
Seq	Timestamp	Type	Name	Duration
0/0	2026/06/30 06:06	flow	patch-triage	1m Args: null Results: { "EnableConfigs": [ "NF_CONNTRACK", "NF_CONNTRACK_SIP", "NF_CT_NETLINK", "NF_CT_NETLINK_HELPER", "NETFILTER_NETLINK_QUEUE", "NF_TABLES", "NF_TABLES_INET", "NF_TABLES_NETDEV", "NFT_FIB_IPV4", "NFT_FIB_IPV6", "NFT_FIB_NETDEV", "IP_SET" ], "FocusSymbols": [ "ip_set_dump_do", "ip_set_dump_done", "ctnetlink_alloc_expect", "set_expected_rtp_rtcp", "nfnl_cthelper_expect_policy", "nfqnl_mangle", "nft_fib_validate", "nft_fib_netdev_validate", "nft_payload_set_init", "nft_payload_set_eval", "nft_pipapo_insert" ], "Reasoning": "The patch series introduces significant functional changes to the netfilter subsystem. It adds validation for payload writes and IP/IPv6 headers before mangling, fixes a bug in SIP conntrack expectation, adds state tracking for pipapo set clones to properly handle aborts, and modifies conntrack expectation allocation and initialization. These changes affect core netfilter logic, netlink queue, nftables payload mangling, and pipapo sets, which are all reachable from userspace and should be heavily fuzzed to ensure no regressions or vulnerabilities are introduced.", "WorthFuzzing": true }
1/1	2026/06/30 06:06	action	read-patch-diff	0m Args: null Results: { "PatchDiff": "commit 58582af80852c31a696b9ada2a9b7141bbd60d8d\nAuthor: syz-cluster \u003ctriage@syzkaller.com\u003e\nDate: Tue Jun 30 06:06:01 2026 +0000\n\n syz-cluster: applied patch under review\n\ndiff --git a/net/netfilter/ipset/ip_set_core.c b/net/netfilter/ipset/ip_set_core.c\nindex a531b654b8d964..6cfad152d7d1ba 100644\n--- a/net/netfilter/ipset/ip_set_core.c\n+++ b/net/netfilter/ipset/ip_set_core.c\n@@ -1480,7 +1480,11 @@ ip_set_dump_done(struct netlink_callback cb)\n \t\tstruct ip_set_net inst =\n \t\t\t(struct ip_set_net )cb-\u003eargs[IPSET_CB_NET];\n \t\tip_set_id_t index = (ip_set_id_t)cb-\u003eargs[IPSET_CB_INDEX];\n-\t\tstruct ip_set set = ip_set_ref_netlink(inst, index);\n+\t\tstruct ip_set set;\n+\n+\t\trcu_read_lock();\n+\t\tset = ip_set_ref_netlink(inst, index);\n+\t\trcu_read_unlock();\n \n \t\tif (set-\u003evariant-\u003euref)\n \t\t\tset-\u003evariant-\u003euref(set, cb, false);\n@@ -1686,7 +1690,9 @@ ip_set_dump_do(struct sk_buff skb, struct netlink_callback cb)\n release_refcount:\n \t/ If there was an error or set is done, release set /\n \tif (ret \|\| !cb-\u003eargs[IPSET_CB_ARG0]) {\n+\t\trcu_read_lock();\n \t\tset = ip_set_ref_netlink(inst, index);\n+\t\trcu_read_unlock();\n \t\tif (set-\u003evariant-\u003euref)\n \t\t\tset-\u003evariant-\u003euref(set, cb, false);\n \t\tpr_debug(\"release set %s\\n\", set-\u003ename);\ndiff --git a/net/netfilter/nf_conntrack_expect.c b/net/netfilter/nf_conntrack_expect.c\nindex 38630c5e006f08..7ae68d60586a23 100644\n--- a/net/netfilter/nf_conntrack_expect.c\n+++ b/net/netfilter/nf_conntrack_expect.c\n@@ -306,7 +306,7 @@ struct nf_conntrack_expect nf_ct_expect_alloc(struct nf_conn me)\n {\n \tstruct nf_conntrack_expect new;\n \n-\tnew = kmem_cache_alloc(nf_ct_expect_cachep, GFP_ATOMIC);\n+\tnew = kmem_cache_zalloc(nf_ct_expect_cachep, GFP_ATOMIC);\n \tif (!new)\n \t\treturn NULL;\n \n@@ -391,6 +391,7 @@ void nf_ct_expect_init(struct nf_conntrack_expect exp, unsigned int class,\n #if IS_ENABLED(CONFIG_NF_NAT)\n \tmemset(\u0026exp-\u003esaved_addr, 0, sizeof(exp-\u003esaved_addr));\n \tmemset(\u0026exp-\u003esaved_proto, 0, sizeof(exp-\u003esaved_proto));\n+\texp-\u003edir = 0;\n #endif\n }\n EXPORT_SYMBOL_GPL(nf_ct_expect_init);\ndiff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c\nindex 4217715d42dc24..31cbb1b55b9e6c 100644\n--- a/net/netfilter/nf_conntrack_netlink.c\n+++ b/net/netfilter/nf_conntrack_netlink.c\n@@ -3549,8 +3549,6 @@ ctnetlink_alloc_expect(const struct nlattr const cda[], struct nf_conn ct,\n \tif (cda[CTA_EXPECT_FLAGS]) {\n \t\texp-\u003eflags = ntohl(nla_get_be32(cda[CTA_EXPECT_FLAGS]));\n \t\texp-\u003eflags \u0026= ~NF_CT_EXPECT_USERSPACE;\n-\t} else {\n-\t\texp-\u003eflags = 0;\n \t}\n \tif (cda[CTA_EXPECT_FN]) {\n \t\tconst char name = nla_data(cda[CTA_EXPECT_FN]);\n@@ -3562,8 +3560,7 @@ ctnetlink_alloc_expect(const struct nlattr * const cda[], struct nf_conn ct,\n \t\t\tgoto err_out;\n \t\t}\n \t\texp-\u003eexpectfn = expfn-\u003eexpectfn;\n-\t} else\n-\t\texp-\u003eexpectfn = NULL;\n+\t}\n \n \texp-\u003eclass = class;\n \texp-\u003emaster = ct;\n@@ -3583,12 +3580,6 @@ ctnetlink_alloc_expect(const struct nlattr const cda[], struct nf_conn ct,\n \t\t\t\t\t\t exp, nf_ct_l3num(ct));\n \t\tif (err \u003c 0)\n \t\t\tgoto err_out;\n-#if IS_ENABLED(CONFIG_NF_NAT)\n-\t} else {\n-\t\tmemset(\u0026exp-\u003esaved_addr, 0, sizeof(exp-\u003esaved_addr));\n-\t\tmemset(\u0026exp-\u003esaved_proto, 0, sizeof(exp-\u003esaved_proto));\n-\t\texp-\u003edir = 0;\n-#endif\n \t}\n \treturn exp;\n err_out:\ndiff --git a/net/netfilter/nf_conntrack_sip.c b/net/netfilter/nf_conntrack_sip.c\nindex 5ec3a4a4bbd707..f3f90a86633894 100644\n--- a/net/netfilter/nf_conntrack_sip.c\n+++ b/net/netfilter/nf_conntrack_sip.c\n@@ -956,7 +956,6 @@ static int set_expected_rtp_rtcp(struct sk_buff skb, unsigned int protoff,\n \t\t\treturn NF_ACCEPT;\n \t\tsaddr = \u0026ct-\u003etuplehash[!dir].tuple.src.u3;\n \t} else if (sip_external_media) {\n-\t\tstruct net_device dev = skb_dst(skb)-\u003edev;\n \t\tstruct dst_entry dst = NULL;\n \t\tstruct flowi fl;\n \n@@ -978,7 +977,11 @@ static int set_expected_rtp_rtcp(struct sk_buff skb, unsigned int protoff,\n \t\t through the same interface as the signalling peer.\n \t\t /\n \t\tif (dst) {\n-\t\t\tbool external_media = (dst-\u003edev == dev);\n+\t\t\tconst struct dst_entry this_dst = skb_dst(skb);\n+\t\t\tbool external_media = false;\n+\n+\t\t\tif (this_dst \u0026\u0026 dst-\u003edev == this_dst-\u003edev)\n+\t\t\t\texternal_media = true;\n \n \t\t\tdst_release(dst);\n \t\t\tif (external_media)\ndiff --git a/net/netfilter/nfnetlink_cthelper.c b/net/netfilter/nfnetlink_cthelper.c\nindex f1460b683d7af7..2cbcca9110dbf5 100644\n--- a/net/netfilter/nfnetlink_cthelper.c\n+++ b/net/netfilter/nfnetlink_cthelper.c\n@@ -163,6 +163,8 @@ nfnl_cthelper_expect_policy(struct nf_conntrack_expect_policy expect_policy,\n \t\t tb[NFCTH_POLICY_NAME], NF_CT_HELPER_NAME_LEN);\n \texpect_policy-\u003emax_expected =\n \t\tntohl(nla_get_be32(tb[NFCTH_POLICY_EXPECT_MAX]));\n+\tif (!expect_policy-\u003emax_expected)\n+\t\texpect_policy-\u003emax_expected = NF_CT_EXPECT_MAX_CNT;\n \tif (expect_policy-\u003emax_expected \u003e NF_CT_EXPECT_MAX_CNT)\n \t\treturn -EINVAL;\n \ndiff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c\nindex 80ca077b81bd5a..35d4c6c628ffc1 100644\n--- a/net/netfilter/nfnetlink_queue.c\n+++ b/net/netfilter/nfnetlink_queue.c\n@@ -1184,6 +1184,173 @@ nfqnl_enqueue_packet(struct nf_queue_entry entry, unsigned int queuenum)\n \treturn err;\n }\n \n+static bool nfqnl_validate_ipopts(const struct iphdr iph_new,\n+\t\t\t\t const struct nf_queue_entry e)\n+{\n+\tconst struct iphdr iph_orig = ip_hdr(e-\u003eskb);\n+\tunsigned int ihl = iph_new-\u003eihl 4;\n+\n+\tif (iph_new-\u003eihl != iph_orig-\u003eihl)\n+\t\treturn false;\n+\tif (ihl == sizeof(iph_orig))\n+\t\treturn true;\n+\n+\treturn memcmp(iph_new + 1, ip_hdr(e-\u003eskb) + 1, ihl - sizeof(iph_orig)) == 0;\n+}\n+\n+static bool nfqnl_validate_ip4(const struct iphdr iph, unsigned int data_len,\n+\t\t\t const struct nf_queue_entry e)\n+{\n+\tunsigned int ihl;\n+\n+\tif (data_len \u003c sizeof(iph))\n+\t\treturn false;\n+\n+\tihl = iph-\u003eihl 4u;\n+\tif (ihl \u003c sizeof(iph) \|\| data_len \u003c ihl)\n+\t\treturn false;\n+\n+\tif (iph-\u003eversion != 4 \|\|\n+\t ((iph-\u003efrag_off ^ ip_hdr(e-\u003eskb)-\u003efrag_off) \u0026 ~htons(IP_DF)) != 0)\n+\t\treturn false;\n+\n+\t/ BIG TCP won't work; netlink attr len is u16 /\n+\tif (ntohs(iph-\u003etot_len) != data_len)\n+\t\treturn false;\n+\n+\t/ support for ipopts mangling would require\n+\t * recompile + skb transport header update.\n+\t /\n+\treturn nfqnl_validate_ipopts(iph, e);\n+}\n+\n+static bool nfqnl_validate_one_exthdr(const u8 data,\n+\t\t\t\t unsigned int data_len,\n+\t\t\t\t const struct nf_queue_entry e,\n+\t\t\t\t int start, int hdrlen)\n+{\n+\tu16 octets;\n+\n+\tif (data_len \u003c hdrlen \|\| hdrlen \u003c 2)\n+\t\treturn false;\n+\n+\twhile (hdrlen \u003e 0) {\n+\t\tif (data_len \u003c sizeof(octets))\n+\t\t\treturn false;\n+\t\tdata_len -= sizeof(octets);\n+\n+\t\tif (skb_copy_bits(e-\u003eskb, start, \u0026octets, sizeof(octets)))\n+\t\t\treturn false;\n+\n+\t\tif (hdrlen \u003c sizeof(octets))\n+\t\t\treturn false;\n+\n+\t\thdrlen -= sizeof(octets);\n+\t\tif (memcmp(data, \u0026octets, sizeof(octets)))\n+\t\t\treturn false;\n+\n+\t\tstart += sizeof(octets);\n+\t\tdata += sizeof(octets);\n+\t}\n+\n+\treturn true;\n+}\n+\n+static bool nfqnl_validate_exthdr(const struct ipv6hdr ip6_new,\n+\t\t\t\t unsigned int data_len,\n+\t\t\t\t const struct nf_queue_entry e)\n+{\n+\tconst struct ipv6hdr ip6_orig = ipv6_hdr(e-\u003eskb);\n+\tint exthdr_cnt = 0, start = sizeof(ip6_orig);\n+\tconst u8 data = (const u8 )ip6_new;\n+\tu8 orig_nexthdr = ip6_orig-\u003enexthdr;\n+\tu8 new_nexthdr = ip6_new-\u003enexthdr;\n+\n+\tif (new_nexthdr != orig_nexthdr)\n+\t\treturn false;\n+\n+\tdata += sizeof(ip6_new);\n+\tdata_len -= sizeof(ip6_new);\n+\n+\twhile (ipv6_ext_hdr(orig_nexthdr)) {\n+\t\tconst struct ipv6_opt_hdr hp;\n+\t\tstruct ipv6_opt_hdr _hdr;\n+\t\tint hdrlen;\n+\n+\t\tif (orig_nexthdr == NEXTHDR_NONE)\n+\t\t\treturn true;\n+\n+\t\tif (unlikely(exthdr_cnt++ \u003e= IP6_MAX_EXT_HDRS_CNT))\n+\t\t\treturn false;\n+\n+\t\thp = skb_header_pointer(e-\u003eskb, start, sizeof(_hdr), \u0026_hdr);\n+\t\tif (!hp)\n+\t\t\treturn false;\n+\n+\t\tswitch (orig_nexthdr) {\n+\t\tcase NEXTHDR_FRAGMENT:\n+\t\t\thdrlen = sizeof(struct frag_hdr);\n+\t\t\tbreak;\n+\t\tcase NEXTHDR_AUTH:\n+\t\t\thdrlen = ipv6_authlen(hp);\n+\t\t\tbreak;\n+\t\tdefault:\n+\t\t\thdrlen = ipv6_optlen(hp);\n+\t\t\tbreak;\n+\t\t}\n+\n+\t\tif (!nfqnl_validate_one_exthdr(data, data_len, e,\n+\t\t\t\t\t start, hdrlen))\n+\t\t\treturn false;\n+\n+\t\torig_nexthdr = hp-\u003enexthdr;\n+\t\thp = (const void )data;\n+\t\tnew_nexthdr = hp-\u003enexthdr;\n+\n+\t\tif (new_nexthdr != orig_nexthdr)\n+\t\t\treturn false;\n+\n+\t\tdata_len -= hdrlen;\n+\t\tstart += hdrlen;\n+\t\tdata += hdrlen;\n+\t}\n+\n+\treturn true;\n+}\n+\n+static bool nfqnl_validate_ip6(const struct ipv6hdr ip6, unsigned int data_len,\n+\t\t\t const struct nf_queue_entry e)\n+{\n+\tif (data_len \u003c sizeof(ip6))\n+\t\treturn false;\n+\n+\t/* BIG TCP/jumbograms won't work; netlink attr len is u16 /\n+\tif (ntohs(ip6-\u003epayload_len) != data_len - sizeof(ip6))\n+\t\treturn false;\n+\n+\tif (ip6-\u003eversion != 6)\n+\t\treturn false;\n+\n+\treturn nfqnl_validate_exthdr(ip6, data_len, e);\n+}\n+\n+static bool nfqnl_validate_write(const void data, unsigned int data_len,\n+\t\t\t\t const struct nf_queue_entry e)\n+{\n+\tswitch (e-\u003estate.pf) {\n+\tcase NFPROTO_IPV4:\n+\t\treturn nfqnl_validate_ip4(data, data_len, e);\n+\tcase NFPROTO_IPV6:\n+\t\treturn nfqnl_validate_ip6(data, data_len, e) \u0026\u0026\n+\t\t !(IP6CB(e-\u003eskb)-\u003eflags \u0026 IP6SKB_JUMBOGRAM);\n+\tcase NFPROTO_BRIDGE:\n+\t\t/* No write support. Bridge is dubious: userspace doesn't even see L2 header /\n+\t\treturn false;\n+\t}\n+\n+\treturn false;\n+}\n+\n static int\n nfqnl_mangle(void data, unsigned int data_len, struct nf_queue_entry e, int diff)\n {\n@@ -1192,6 +1359,9 @@ nfqnl_mangle(void data, unsigned int data_len, struct nf_queue_entry e, int di\n \tif (e-\u003estate.net-\u003euser_ns != \u0026init_user_ns)\n \t\treturn -EPERM;\n \n+\tif (!nfqnl_validate_write(data, data_len, e))\n+\t\treturn -EINVAL;\n+\n \tif (diff \u003c 0) {\n \t\tunsigned int min_len = skb_transport_offset(e-\u003eskb);\n \ndiff --git a/net/netfilter/nft_fib.c b/net/netfilter/nft_fib.c\nindex e048f05694cddd..89555380f1c5a0 100644\n--- a/net/netfilter/nft_fib.c\n+++ b/net/netfilter/nft_fib.c\n@@ -31,6 +31,15 @@ int nft_fib_validate(const struct nft_ctx ctx, const struct nft_expr expr)\n \tconst struct nft_fib priv = nft_expr_priv(expr);\n \tunsigned int hooks;\n \n+\tswitch (ctx-\u003efamily) {\n+\tcase NFPROTO_IPV4:\n+\tcase NFPROTO_IPV6:\n+\tcase NFPROTO_INET:\n+\t\tbreak;\n+\tdefault:\n+\t\treturn -EOPNOTSUPP;\n+\t}\n+\n \tswitch (priv-\u003eresult) {\n \tcase NFT_FIB_RESULT_OIF:\n \tcase NFT_FIB_RESULT_OIFNAME:\ndiff --git a/net/netfilter/nft_fib_netdev.c b/net/netfilter/nft_fib_netdev.c\nindex 3f3478abd84546..5774a754402780 100644\n--- a/net/netfilter/nft_fib_netdev.c\n+++ b/net/netfilter/nft_fib_netdev.c\n@@ -50,6 +50,33 @@ static void nft_fib_netdev_eval(const struct nft_expr expr,\n \tregs-\u003everdict.code = NFT_BREAK;\n }\n \n+static int nft_fib_netdev_validate(const struct nft_ctx ctx,\n+\t\t\t\t const struct nft_expr expr)\n+{\n+\tconst struct nft_fib priv = nft_expr_priv(expr);\n+\tunsigned int hooks;\n+\n+\tswitch (priv-\u003eresult) {\n+\tcase NFT_FIB_RESULT_OIF:\n+\tcase NFT_FIB_RESULT_OIFNAME:\n+\t\thooks = (1 \u003c\u003c NF_NETDEV_INGRESS);\n+\t\tbreak;\n+\tcase NFT_FIB_RESULT_ADDRTYPE:\n+\t\tif (priv-\u003eflags \u0026 NFTA_FIB_F_IIF)\n+\t\t\thooks = (1 \u003c\u003c NF_NETDEV_INGRESS);\n+\t\telse if (priv-\u003eflags \u0026 NFTA_FIB_F_OIF)\n+\t\t\thooks = (1 \u003c\u003c NF_NETDEV_EGRESS);\n+\t\telse\n+\t\t\thooks = (1 \u003c\u003c NF_NETDEV_INGRESS) \|\n+\t\t\t\t(1 \u003c\u003c NF_NETDEV_EGRESS);\n+\t\tbreak;\n+\tdefault:\n+\t\treturn -EINVAL;\n+\t}\n+\n+\treturn nft_chain_validate_hooks(ctx-\u003echain, hooks);\n+}\n+\n static struct nft_expr_type nft_fib_netdev_type;\n static const struct nft_expr_ops nft_fib_netdev_ops = {\n \t.type\t\t= \u0026nft_fib_netdev_type,\n@@ -57,7 +84,7 @@ static const struct nft_expr_ops nft_fib_netdev_ops = {\n \t.eval\t\t= nft_fib_netdev_eval,\n \t.init\t\t= nft_fib_init,\n \t.dump\t\t= nft_fib_dump,\n-\t.validate\t= nft_fib_validate,\n+\t.validate\t= nft_fib_netdev_validate,\n };\n \n static struct nft_expr_type nft_fib_netdev_type __read_mostly = {\ndiff --git a/net/netfilter/nft_payload.c b/net/netfilter/nft_payload.c\nindex 345eff140d56f8..391539a1ceaa77 100644\n--- a/net/netfilter/nft_payload.c\n+++ b/net/netfilter/nft_payload.c\n@@ -834,6 +834,249 @@ nft_payload_set_vlan(const u32 src, struct sk_buff skb, u16 offset, u8 len,\n \treturn true;\n }\n \n+/* Ingress is very early, before l3 protocol handlers.\n+ * There should be no in-tree code that trusts l3/l4 headers\n+ * between ingress and NF_INET_PRE_ROUTING hooks.\n+ /\n+static bool nft_in_ingress(const struct nf_hook_state s)\n+{\n+\treturn s-\u003epf == NFPROTO_NETDEV \u0026\u0026 s-\u003ehook == NF_NETDEV_INGRESS;\n+}\n+\n+static bool nft_nh_write_ok_ip4(const struct nft_pktinfo pkt,\n+\t\t\t\tconst struct nft_payload_set priv,\n+\t\t\t\tconst u32 src)\n+{\n+\tunsigned int offset = priv-\u003eoffset + skb_network_offset(pkt-\u003eskb);\n+\tconst u8 new_octets = (const u8 )src;\n+\tu8 old_octet;\n+\n+\tswitch (priv-\u003eoffset) {\n+\tcase 0: / csum fixups does expand dscp/tos store to 2 bytes.\n+\t\t * make sure ihl/version remain unchanged.\n+\t\t /\n+\t\tif (skb_copy_bits(pkt-\u003eskb, offset, \u0026old_octet, sizeof(old_octet)))\n+\t\t\treturn false;\n+\n+\t\treturn priv-\u003elen == 2 \u0026\u0026\n+\t\t new_octets == old_octet;\n+\tcase offsetof(struct iphdr, tos):\n+\t\treturn priv-\u003elen == 1;\n+\tcase offsetof(struct iphdr, id):\n+\t\treturn priv-\u003elen == 2;\n+\tcase offsetof(struct iphdr, ttl):\n+\t\tif (priv-\u003elen == 1)\n+\t\t\treturn true;\n+\n+\t\tif (priv-\u003elen != 2)\n+\t\t\treturn false;\n+\n+\t\t/* same, csum fixup does expand ttl store to two bytes.\n+\t\t * check protocol is not altered.\n+\t\t /\n+\t\tif (skb_copy_bits(pkt-\u003eskb, offset + 1, \u0026old_octet, sizeof(old_octet)))\n+\t\t\treturn false;\n+\n+\t\treturn new_octets[1] == old_octet;\n+\tcase offsetof(struct iphdr, check):\n+\t\treturn priv-\u003elen \u003c= 2 + 4 + 4;\n+\tcase offsetof(struct iphdr, saddr):\n+\t\treturn priv-\u003elen \u003c= 4 + 4;\n+\tcase offsetof(struct iphdr, daddr):\n+\t\treturn priv-\u003elen \u003c= 4;\n+\t}\n+\n+\treturn false;\n+}\n+\n+static bool nft_nh_write_ok_ip6(const struct nft_pktinfo pkt,\n+\t\t\t\tconst struct nft_payload_set priv,\n+\t\t\t\tconst u32 src)\n+{\n+\tconst struct ipv6hdr ih = (const void )src;\n+\n+\tswitch (priv-\u003eoffset) {\n+\tcase 0: /* store to dscp must not alter ip6 version /\n+\t\treturn priv-\u003elen \u003c= 4 \u0026\u0026 ih-\u003eversion == 6;\n+\tcase 2:\n+\t\treturn priv-\u003elen \u003c= 2;\n+\tcase offsetof(struct ipv6hdr, hop_limit):\n+\t\treturn priv-\u003elen == 1;\n+\tcase offsetof(struct ipv6hdr, saddr):\n+\t\treturn priv-\u003elen \u003c= 16 + 16;\n+\tcase offsetof(struct ipv6hdr, daddr):\n+\t\treturn priv-\u003elen \u003c= 16;\n+\t}\n+\n+\treturn false;\n+}\n+\n+static bool nft_nh_write_ok_arp(const struct nft_payload_set priv)\n+{\n+\t/* Variable size for standard ethernet arp /\n+\tconst unsigned int eth_ip = 2 (ETH_ALEN + 4);\n+\tunsigned int offset = priv-\u003eoffset;\n+\n+\tswitch (offset) {\n+\tcase offsetof(struct arphdr, ar_op):\n+\t\treturn priv-\u003elen == 2;\n+\tdefault:\n+\t\tbreak;\n+\t}\n+\n+\t/* permit writes post fixed arp header size. offset + len are\n+\t * checked vs skb size via skb_ensure_writable.\n+\t /\n+\treturn offset \u003e= sizeof(struct arphdr) \u0026\u0026 priv-\u003elen \u003c= eth_ip;\n+}\n+\n+static bool nft_nh_write_ok_netdev(const struct nft_pktinfo pkt,\n+\t\t\t\t const struct nft_payload_set priv,\n+\t\t\t\t const u32 src)\n+{\n+#ifdef CONFIG_NF_TABLES_NETDEV\n+\tswitch (pkt-\u003eskb-\u003eprotocol) {\n+\tcase htons(ETH_P_ARP):\n+\t\treturn nft_nh_write_ok_arp(priv);\n+\tcase htons(ETH_P_IP):\n+\t\treturn nft_nh_write_ok_ip4(pkt, priv, src);\n+\tcase htons(ETH_P_IPV6):\n+\t\treturn nft_nh_write_ok_ip6(pkt, priv, src);\n+\t}\n+#endif\n+\t/* default to false for now, relax later in case we have\n+\t * use-cases that need inner header manipulation for\n+\t * encapsulated traffic like vlan or PPPoE.\n+\t /\n+\treturn false;\n+}\n+\n+static bool nft_nh_write_ok_bridge(const struct nft_pktinfo pkt,\n+\t\t\t\t const struct nft_payload_set priv,\n+\t\t\t\t const u32 src)\n+{\n+#if IS_ENABLED(CONFIG_NF_TABLES_BRIDGE)\n+\tswitch (pkt-\u003eethertype) {\n+\tcase htons(ETH_P_ARP):\n+\t\treturn nft_nh_write_ok_arp(priv);\n+\tcase htons(ETH_P_IP):\n+\t\treturn nft_nh_write_ok_ip4(pkt, priv, src);\n+\tcase htons(ETH_P_IPV6):\n+\t\treturn nft_nh_write_ok_ip6(pkt, priv, src);\n+\t}\n+#endif\n+\t/* see nft_nh_write_ok_netdev: default to false /\n+\treturn false;\n+}\n+\n+static bool nft_nh_write_ok(const struct nft_pktinfo pkt,\n+\t\t\t const struct nft_payload_set priv,\n+\t\t\t const u32 src)\n+{\n+\tswitch (pkt-\u003estate-\u003epf) {\n+\tcase NFPROTO_ARP:\n+\t\treturn nft_nh_write_ok_arp(priv);\n+\tcase NFPROTO_BRIDGE:\n+\t\treturn nft_nh_write_ok_bridge(pkt, priv, src);\n+\tcase NFPROTO_IPV4:\n+\t\treturn nft_nh_write_ok_ip4(pkt, priv, src);\n+\tcase NFPROTO_IPV6:\n+\t\treturn nft_nh_write_ok_ip6(pkt, priv, src);\n+\tcase NFPROTO_NETDEV:\n+\t\tif (pkt-\u003estate-\u003ehook == NF_NETDEV_INGRESS)\n+\t\t\treturn true;\n+\t\treturn nft_nh_write_ok_netdev(pkt, priv, src);\n+\t}\n+\n+\treturn false;\n+}\n+\n+/* check linklayer modifications don't spill into network header. /\n+static bool nft_ll_write_ok(const struct nft_pktinfo pkt, int offset)\n+{\n+\tif (nft_in_ingress(pkt-\u003estate))\n+\t\treturn true;\n+\n+\treturn offset \u003c= skb_network_offset(pkt-\u003eskb);\n+}\n+\n+static bool nft_payload_validate_inet_csum_offset(const struct nft_ctx ctx,\n+\t\t\t\t\t\t const struct nft_payload_set priv)\n+{\n+\tswitch (priv-\u003ebase) {\n+\tcase NFT_PAYLOAD_LL_HEADER:\n+\t\tbreak;\n+\tcase NFT_PAYLOAD_NETWORK_HEADER:\n+\t\tif (ctx-\u003efamily == NFPROTO_IPV4) {\n+\t\t\tif (offsetof(struct iphdr, check) == priv-\u003ecsum_offset)\n+\t\t\t\treturn true;\n+\n+\t\t\treturn false;\n+\t\t}\n+\t\treturn true; /* run time validation required /\n+\tcase NFT_PAYLOAD_TRANSPORT_HEADER:\n+\t\tif (priv-\u003ecsum_flags) / makes no sense, asks for \"re-update\" of L4 checksum /\n+\t\t\treturn false;\n+\n+\t\t/ no further check here; offset can't be negative so bogus\n+\t\t * offsets can corrupt L4 or payload but not l3 headers.\n+\t\t * We already allow arbitrary l4/inner payload writes.\n+\t\t /\n+\t\treturn true;\n+\tcase NFT_PAYLOAD_INNER_HEADER:\n+\t\treturn true;\n+\tcase NFT_PAYLOAD_TUN_HEADER:\n+\t\tbreak;\n+\t}\n+\n+\treturn false;\n+}\n+\n+/ do not allow arbitrary network header mangling via bogus csum_off.\n+ * We only support ipv4. Only NFPROTO_IPV4 can be checked from control\n+ * plane.\n+ /\n+static bool nft_payload_csum_nh_write_ok(const struct nft_payload_set priv,\n+\t\t\t\t\t const struct nft_pktinfo pkt)\n+{\n+\tswitch (pkt-\u003estate-\u003epf) {\n+\tcase NFPROTO_IPV4:\n+\t\t/ Warning: NFPROTO_INET was not checked; we can't return true here. /\n+\t\treturn priv-\u003ecsum_offset == offsetof(struct iphdr, check);\n+\tcase NFPROTO_IPV6:\n+\t\treturn false;\n+\tcase NFPROTO_BRIDGE:\n+\t\treturn pkt-\u003eethertype == htons(ETH_P_IP) \u0026\u0026\n+\t\t priv-\u003ecsum_offset == offsetof(struct iphdr, check);\n+\tcase NFPROTO_NETDEV:\n+\t\treturn pkt-\u003eskb-\u003eprotocol == htons(ETH_P_IP) \u0026\u0026\n+\t\t priv-\u003ecsum_offset == offsetof(struct iphdr, check);\n+\t}\n+\n+\treturn false;\n+}\n+\n+static bool nft_payload_csum_write_ok(const struct nft_pktinfo pkt,\n+\t\t\t\t const struct nft_payload_set priv)\n+{\n+\tswitch (priv-\u003ebase) {\n+\tcase NFT_PAYLOAD_LL_HEADER:\n+\t\tbreak;\n+\tcase NFT_PAYLOAD_NETWORK_HEADER:\n+\t\treturn nft_payload_csum_nh_write_ok(priv, pkt);\n+\tcase NFT_PAYLOAD_TRANSPORT_HEADER:\n+\tcase NFT_PAYLOAD_INNER_HEADER:\n+\t\t/ neither offsets are validated, offsets cannot be\n+\t\t * negative so real l3 headers cannot be mangled.\n+\t\t /\n+\t\treturn true;\n+\tcase NFT_PAYLOAD_TUN_HEADER:\n+\t\tbreak;\n+\t}\n+\n+\treturn false;\n+}\n+\n static void nft_payload_set_eval(const struct nft_expr expr,\n \t\t\t\t struct nft_regs regs,\n \t\t\t\t const struct nft_pktinfo pkt)\n@@ -861,8 +1104,12 @@ static void nft_payload_set_eval(const struct nft_expr expr,\n \t\t}\n \n \t\toffset = skb_mac_header(skb) - skb-\u003edata - vlan_hlen;\n+\t\tif (!nft_ll_write_ok(pkt, priv-\u003elen + priv-\u003eoffset + offset))\n+\t\t\tgoto err;\n \t\tbreak;\n \tcase NFT_PAYLOAD_NETWORK_HEADER:\n+\t\tif (!nft_nh_write_ok(pkt, priv, src))\n+\t\t\tgoto err;\n \t\toffset = skb_network_offset(skb);\n \t\tbreak;\n \tcase NFT_PAYLOAD_TRANSPORT_HEADER:\n@@ -894,6 +1141,7 @@ static void nft_payload_set_eval(const struct nft_expr expr,\n \t\ttsum = csum_partial(src, priv-\u003elen, 0);\n \n \t\tif (priv-\u003ecsum_type == NFT_PAYLOAD_CSUM_INET \u0026\u0026\n+\t\t nft_payload_csum_write_ok(pkt, priv) \u0026\u0026\n \t\t nft_payload_csum_inet(skb, src, fsum, tsum, csum_offset))\n \t\t\tgoto err;\n \n@@ -960,7 +1208,26 @@ static int nft_payload_set_init(const struct nft_ctx ctx,\n \n \tswitch (csum_type) {\n \tcase NFT_PAYLOAD_CSUM_NONE:\n+\t\tif (priv-\u003ecsum_offset) / nonsensical /\n+\t\t\treturn -EINVAL;\n+\n+\t\tif (priv-\u003ecsum_flags == 0)\n+\t\t\tbreak;\n+\n+\t\t/ Userspace requests L4 checksum update, e.g.:\n+\t\t * - IPv6 stateless NAT (no l3 csum)\n+\t\t * - transport header mangling\n+\t\t * - inner data mangling\n+\t\t /\n+\t\tif (priv-\u003ebase == NFT_PAYLOAD_NETWORK_HEADER \|\|\n+\t\t priv-\u003ebase == NFT_PAYLOAD_TRANSPORT_HEADER \|\|\n+\t\t priv-\u003ebase == NFT_PAYLOAD_INNER_HEADER)\n+\t\t\tbreak;\n+\n+\t\treturn -EINVAL;\n \tcase NFT_PAYLOAD_CSUM_INET:\n+\t\tif (!nft_payload_validate_inet_csum_offset(ctx, priv))\n+\t\t\treturn -EINVAL;\n \t\tbreak;\n \tcase NFT_PAYLOAD_CSUM_SCTP:\n \t\tif (priv-\u003ebase != NFT_PAYLOAD_TRANSPORT_HEADER)\n@@ -968,6 +1235,9 @@ static int nft_payload_set_init(const struct nft_ctx ctx,\n \n \t\tif (priv-\u003ecsum_offset != offsetof(struct sctphdr, checksum))\n \t\t\treturn -EINVAL;\n+\n+\t\tif (priv-\u003ecsum_flags)\n+\t\t\treturn -EINVAL;\n \t\tbreak;\n \tdefault:\n \t\treturn -EOPNOTSUPP;\ndiff --git a/net/netfilter/nft_set_pipapo.c b/net/netfilter/nft_set_pipapo.c\nindex 706c78853f245b..978bb0c0110682 100644\n--- a/net/netfilter/nft_set_pipapo.c\n+++ b/net/netfilter/nft_set_pipapo.c\n@@ -342,6 +342,8 @@\n #include \"nft_set_pipapo_avx2.h\"\n #include \"nft_set_pipapo.h\"\n \n+static void nft_pipapo_abort(const struct nft_set set);\n+\n /\n pipapo_refill() - For each set bit, set bits from selected mapping table item\n * @map:\tBitmap to be scanned for set bits\n@@ -1296,7 +1298,7 @@ static int nft_pipapo_insert(const struct net net, const struct nft_set set,\n \tconst u8 start_p, end_p;\n \tint i, bsize_max, err = 0;\n \n-\tif (!m)\n+\tif (!m \|\| m-\u003estate == NFT_PIPAPO_CLONE_ERR)\n \t\treturn -ENOMEM;\n \n \tif (nft_set_ext_exists(ext, NFT_SET_EXT_KEY_END))\n@@ -1367,8 +1369,10 @@ static int nft_pipapo_insert(const struct net net, const struct nft_set set,\n \t\telse\n \t\t\tret = pipapo_expand(f, start, end, f-\u003egroups * f-\u003ebb);\n \n-\t\tif (ret \u003c 0)\n-\t\t\treturn ret;\n+\t\tif (ret \u003c 0) {\n+\t\t\terr = ret;\n+\t\t\tgoto abort;\n+\t\t}\n \n \t\tif (f-\u003ebsize \u003e bsize_max)\n \t\t\tbsize_max = f-\u003ebsize;\n@@ -1384,7 +1388,7 @@ static int nft_pipapo_insert(const struct net net, const struct nft_set set,\n \n \t\terr = pipapo_realloc_scratch(m, bsize_max);\n \t\tif (err)\n-\t\t\treturn err;\n+\t\t\tgoto abort;\n \n \t\tm-\u003ebsize_max = bsize_max;\n \t} else {\n@@ -1396,7 +1400,26 @@ static int nft_pipapo_insert(const struct net net, const struct nft_set set,\n \n \tpipapo_map(m, rulemap, e);\n \n+\tm-\u003estate = NFT_PIPAPO_CLONE_MOD;\n \treturn 0;\n+abort:\n+\tDEBUG_NET_WARN_ON_ONCE(m-\u003estate == NFT_PIPAPO_CLONE_ERR);\n+\n+\t/* Two rollback cases:\n+\t * 1) no previous changes. nft_pipapo_abort is not\n+\t * guaranteed to be invoked (there might be no further\n+\t * add/delete requests coming after this).\n+\t \n+\t 2) we had previous changes: there are transaction\n+\t * records pointing to this set. Leave the rollback to\n+\t * the transaction handling.\n+\t /\n+\tif (m-\u003estate == NFT_PIPAPO_CLONE_NEW)\n+\t\tnft_pipapo_abort(set); / releases m /\n+\telse\n+\t\tm-\u003estate = NFT_PIPAPO_CLONE_ERR;\n+\n+\treturn err;\n }\n \n /\n@@ -1473,6 +1496,7 @@ static struct nft_pipapo_match pipapo_clone(struct nft_pipapo_match old)\n \t\tdst++;\n \t}\n \n+\tnew-\u003estate = NFT_PIPAPO_CLONE_NEW;\n \treturn new;\n \n out_mt:\n@@ -1896,7 +1920,7 @@ nft_pipapo_deactivate(const struct net net, const struct nft_set set,\n \t/ removal must occur on priv-\u003eclone, if we are low on memory\n \t * we have no choice and must fail the removal request.\n \t /\n-\tif (!m)\n+\tif (!m \|\| m-\u003estate == NFT_PIPAPO_CLONE_ERR)\n \t\treturn NULL;\n \n \te = pipapo_get(m, (const u8 )elem-\u003ekey.val.data,\ndiff --git a/net/netfilter/nft_set_pipapo.h b/net/netfilter/nft_set_pipapo.h\nindex b82abb03576edd..a19e980d06ef42 100644\n--- a/net/netfilter/nft_set_pipapo.h\n+++ b/net/netfilter/nft_set_pipapo.h\n@@ -131,9 +131,16 @@ struct nft_pipapo_scratch {\n \tunsigned long __map[];\n };\n \n+enum nft_pipapo_clone_state {\n+\tNFT_PIPAPO_CLONE_NEW,\n+\tNFT_PIPAPO_CLONE_MOD,\n+\tNFT_PIPAPO_CLONE_ERR,\n+};\n+\n /*\n struct nft_pipapo_match - Data used for lookup and matching\n * @field_count:\tAmount of fields in set\n+ * @state:\t\tadd/delete state; used from control plane\n * @bsize_max:\t\tMaximum lookup table bucket size of all fields, in longs\n * @scratch:\t\tPreallocated per-CPU maps for partial matching results\n * @rcu:\t\tMatching data is swapped on commits\n@@ -141,6 +148,7 @@ struct nft_pipapo_scratch {\n /\n struct nft_pipapo_match {\n \tu8 field_count;\n+\tenum nft_pipapo_clone_state state:8;\n \tunsigned int bsize_max;\n \tstruct nft_pipapo_scratch __percpu *scratch;\n \tstruct rcu_head rcu;\n" }
2/1	2026/06/30 06:06	agent	patch-evaluator	1m Model: gemini-3.1-pro-preview Args: null Results: { "EnableConfigs": [ "NF_CONNTRACK", "NF_CONNTRACK_SIP", "NF_CT_NETLINK", "NF_CT_NETLINK_HELPER", "NETFILTER_NETLINK_QUEUE", "NF_TABLES", "NF_TABLES_INET", "NF_TABLES_NETDEV", "NFT_FIB_IPV4", "NFT_FIB_IPV6", "NFT_FIB_NETDEV", "IP_SET" ], "FocusSymbols": [ "ip_set_dump_do", "ip_set_dump_done", "ctnetlink_alloc_expect", "set_expected_rtp_rtcp", "nfnl_cthelper_expect_policy", "nfqnl_mangle", "nft_fib_validate", "nft_fib_netdev_validate", "nft_payload_set_init", "nft_payload_set_eval", "nft_pipapo_insert" ], "Reasoning": "The patch series introduces significant functional changes to the netfilter subsystem. It adds validation for payload writes and IP/IPv6 headers before mangling, fixes a bug in SIP conntrack expectation, adds state tracking for pipapo set clones to properly handle aborts, and modifies conntrack expectation allocation and initialization. These changes affect core netfilter logic, netlink queue, nftables payload mangling, and pipapo sets, which are all reachable from userspace and should be heavily fuzzed to ensure no regressions or vulnerabilities are introduced.", "WorthFuzzing": true } Instruction: You are an expert Linux kernel maintainer. Your job is to review a provided patch series and determine if it makes functional changes to the kernel that should be fuzzed. IMPORTANT: The changes have ALREADY been applied and committed as the HEAD commit in your workspace. Do NOT rely on your internal knowledge of the kernel. You must actively use your code access tools to examine the actual source code and confirm any assumptions. Return WorthFuzzing=false if the patch only contains: - Modifications to Documentation/, Kconfig files, or code comments. - Purely decorative changes, such as logging (e.g., pr_err, printk) or tracepoints. - Changes to numeric constants or macros that do not functionally alter execution flow. - Code paths that are impossible to reach in virtualized environments like GCE or QEMU, even when utilizing software-emulated hardware (e.g., usb gadget, mac80211_hwsim). If it modifies reachable core kernel logic, drivers, or architectures, use your code search tools to verify the code can be executed, then return WorthFuzzing=true. When returning WorthFuzzing=true, you MUST ALSO: 1. Extract any specific kernel functions that should be heavily fuzzed into FocusSymbols. Avoid listing generic hot-path functions to prevent skewed test distributions. 2. Identify any specific CONFIG_ options required to properly test this new/modified feature. Go and look into the Kconfig files and check for ifdefs around the code, do not make assumptions. Do not list too generic configs (we already have them enabled). Only list those that specifically cover the modified code. List them in the EnableConfigs output array, and DO NOT add a '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: For your convenience, here is the diff of the changes: commit 58582af80852c31a696b9ada2a9b7141bbd60d8d Author: syz-cluster <triage@syzkaller.com> Date: Tue Jun 30 06:06:01 2026 +0000 syz-cluster: applied patch under review diff --git a/net/netfilter/ipset/ip_set_core.c b/net/netfilter/ipset/ip_set_core.c index a531b654b8d964..6cfad152d7d1ba 100644 --- a/net/netfilter/ipset/ip_set_core.c +++ b/net/netfilter/ipset/ip_set_core.c @@ -1480,7 +1480,11 @@ ip_set_dump_done(struct netlink_callback cb) struct ip_set_net inst = (struct ip_set_net )cb->args[IPSET_CB_NET]; ip_set_id_t index = (ip_set_id_t)cb->args[IPSET_CB_INDEX]; - struct ip_set set = ip_set_ref_netlink(inst, index); + struct ip_set set; + + rcu_read_lock(); + set = ip_set_ref_netlink(inst, index); + rcu_read_unlock(); if (set->variant->uref) set->variant->uref(set, cb, false); @@ -1686,7 +1690,9 @@ ip_set_dump_do(struct sk_buff skb, struct netlink_callback cb) release_refcount: / If there was an error or set is done, release set / if (ret \|\| !cb->args[IPSET_CB_ARG0]) { + rcu_read_lock(); set = ip_set_ref_netlink(inst, index); + rcu_read_unlock(); if (set->variant->uref) set->variant->uref(set, cb, false); pr_debug("release set %s\n", set->name); diff --git a/net/netfilter/nf_conntrack_expect.c b/net/netfilter/nf_conntrack_expect.c index 38630c5e006f08..7ae68d60586a23 100644 --- a/net/netfilter/nf_conntrack_expect.c +++ b/net/netfilter/nf_conntrack_expect.c @@ -306,7 +306,7 @@ struct nf_conntrack_expect nf_ct_expect_alloc(struct nf_conn me) { struct nf_conntrack_expect new; - new = kmem_cache_alloc(nf_ct_expect_cachep, GFP_ATOMIC); + new = kmem_cache_zalloc(nf_ct_expect_cachep, GFP_ATOMIC); if (!new) return NULL; @@ -391,6 +391,7 @@ void nf_ct_expect_init(struct nf_conntrack_expect exp, unsigned int class, #if IS_ENABLED(CONFIG_NF_NAT) memset(&exp->saved_addr, 0, sizeof(exp->saved_addr)); memset(&exp->saved_proto, 0, sizeof(exp->saved_proto)); + exp->dir = 0; #endif } EXPORT_SYMBOL_GPL(nf_ct_expect_init); diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c index 4217715d42dc24..31cbb1b55b9e6c 100644 --- a/net/netfilter/nf_conntrack_netlink.c +++ b/net/netfilter/nf_conntrack_netlink.c @@ -3549,8 +3549,6 @@ ctnetlink_alloc_expect(const struct nlattr const cda[], struct nf_conn ct, if (cda[CTA_EXPECT_FLAGS]) { exp->flags = ntohl(nla_get_be32(cda[CTA_EXPECT_FLAGS])); exp->flags &= ~NF_CT_EXPECT_USERSPACE; - } else { - exp->flags = 0; } if (cda[CTA_EXPECT_FN]) { const char name = nla_data(cda[CTA_EXPECT_FN]); @@ -3562,8 +3560,7 @@ ctnetlink_alloc_expect(const struct nlattr * const cda[], struct nf_conn ct, goto err_out; } exp->expectfn = expfn->expectfn; - } else - exp->expectfn = NULL; + } exp->class = class; exp->master = ct; @@ -3583,12 +3580,6 @@ ctnetlink_alloc_expect(const struct nlattr const cda[], struct nf_conn ct, exp, nf_ct_l3num(ct)); if (err < 0) goto err_out; -#if IS_ENABLED(CONFIG_NF_NAT) - } else { - memset(&exp->saved_addr, 0, sizeof(exp->saved_addr)); - memset(&exp->saved_proto, 0, sizeof(exp->saved_proto)); - exp->dir = 0; -#endif } return exp; err_out: diff --git a/net/netfilter/nf_conntrack_sip.c b/net/netfilter/nf_conntrack_sip.c index 5ec3a4a4bbd707..f3f90a86633894 100644 --- a/net/netfilter/nf_conntrack_sip.c +++ b/net/netfilter/nf_conntrack_sip.c @@ -956,7 +956,6 @@ static int set_expected_rtp_rtcp(struct sk_buff skb, unsigned int protoff, return NF_ACCEPT; saddr = &ct->tuplehash[!dir].tuple.src.u3; } else if (sip_external_media) { - struct net_device dev = skb_dst(skb)->dev; struct dst_entry dst = NULL; struct flowi fl; @@ -978,7 +977,11 @@ static int set_expected_rtp_rtcp(struct sk_buff skb, unsigned int protoff, through the same interface as the signalling peer. / if (dst) { - bool external_media = (dst->dev == dev); + const struct dst_entry this_dst = skb_dst(skb); + bool external_media = false; + + if (this_dst && dst->dev == this_dst->dev) + external_media = true; dst_release(dst); if (external_media) diff --git a/net/netfilter/nfnetlink_cthelper.c b/net/netfilter/nfnetlink_cthelper.c index f1460b683d7af7..2cbcca9110dbf5 100644 --- a/net/netfilter/nfnetlink_cthelper.c +++ b/net/netfilter/nfnetlink_cthelper.c @@ -163,6 +163,8 @@ nfnl_cthelper_expect_policy(struct nf_conntrack_expect_policy expect_policy, tb[NFCTH_POLICY_NAME], NF_CT_HELPER_NAME_LEN); expect_policy->max_expected = ntohl(nla_get_be32(tb[NFCTH_POLICY_EXPECT_MAX])); + if (!expect_policy->max_expected) + expect_policy->max_expected = NF_CT_EXPECT_MAX_CNT; if (expect_policy->max_expected > NF_CT_EXPECT_MAX_CNT) return -EINVAL; diff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c index 80ca077b81bd5a..35d4c6c628ffc1 100644 --- a/net/netfilter/nfnetlink_queue.c +++ b/net/netfilter/nfnetlink_queue.c @@ -1184,6 +1184,173 @@ nfqnl_enqueue_packet(struct nf_queue_entry entry, unsigned int queuenum) return err; } +static bool nfqnl_validate_ipopts(const struct iphdr iph_new, + const struct nf_queue_entry e) +{ + const struct iphdr iph_orig = ip_hdr(e->skb); + unsigned int ihl = iph_new->ihl 4; + + if (iph_new->ihl != iph_orig->ihl) + return false; + if (ihl == sizeof(iph_orig)) + return true; + + return memcmp(iph_new + 1, ip_hdr(e->skb) + 1, ihl - sizeof(iph_orig)) == 0; +} + +static bool nfqnl_validate_ip4(const struct iphdr iph, unsigned int data_len, + const struct nf_queue_entry e) +{ + unsigned int ihl; + + if (data_len < sizeof(iph)) + return false; + + ihl = iph->ihl 4u; + if (ihl < sizeof(iph) \|\| data_len < ihl) + return false; + + if (iph->version != 4 \|\| + ((iph->frag_off ^ ip_hdr(e->skb)->frag_off) & ~htons(IP_DF)) != 0) + return false; + + / BIG TCP won't work; netlink attr len is u16 / + if (ntohs(iph->tot_len) != data_len) + return false; + + / support for ipopts mangling would require + * recompile + skb transport header update. + / + return nfqnl_validate_ipopts(iph, e); +} + +static bool nfqnl_validate_one_exthdr(const u8 data, + unsigned int data_len, + const struct nf_queue_entry e, + int start, int hdrlen) +{ + u16 octets; + + if (data_len < hdrlen \|\| hdrlen < 2) + return false; + + while (hdrlen > 0) { + if (data_len < sizeof(octets)) + return false; + data_len -= sizeof(octets); + + if (skb_copy_bits(e->skb, start, &octets, sizeof(octets))) + return false; + + if (hdrlen < sizeof(octets)) + return false; + + hdrlen -= sizeof(octets); + if (memcmp(data, &octets, sizeof(octets))) + return false; + + start += sizeof(octets); + data += sizeof(octets); + } + + return true; +} + +static bool nfqnl_validate_exthdr(const struct ipv6hdr ip6_new, + unsigned int data_len, + const struct nf_queue_entry e) +{ + const struct ipv6hdr ip6_orig = ipv6_hdr(e->skb); + int exthdr_cnt = 0, start = sizeof(ip6_orig); + const u8 data = (const u8 )ip6_new; + u8 orig_nexthdr = ip6_orig->nexthdr; + u8 new_nexthdr = ip6_new->nexthdr; + + if (new_nexthdr != orig_nexthdr) + return false; + + data += sizeof(ip6_new); + data_len -= sizeof(ip6_new); + + while (ipv6_ext_hdr(orig_nexthdr)) { + const struct ipv6_opt_hdr hp; + struct ipv6_opt_hdr _hdr; + int hdrlen; + + if (orig_nexthdr == NEXTHDR_NONE) + return true; + + if (unlikely(exthdr_cnt++ >= IP6_MAX_EXT_HDRS_CNT)) + return false; + + hp = skb_header_pointer(e->skb, start, sizeof(_hdr), &_hdr); + if (!hp) + return false; + + switch (orig_nexthdr) { + case NEXTHDR_FRAGMENT: + hdrlen = sizeof(struct frag_hdr); + break; + case NEXTHDR_AUTH: + hdrlen = ipv6_authlen(hp); + break; + default: + hdrlen = ipv6_optlen(hp); + break; + } + + if (!nfqnl_validate_one_exthdr(data, data_len, e, + start, hdrlen)) + return false; + + orig_nexthdr = hp->nexthdr; + hp = (const void )data; + new_nexthdr = hp->nexthdr; + + if (new_nexthdr != orig_nexthdr) + return false; + + data_len -= hdrlen; + start += hdrlen; + data += hdrlen; + } + + return true; +} + +static bool nfqnl_validate_ip6(const struct ipv6hdr ip6, unsigned int data_len, + const struct nf_queue_entry e) +{ + if (data_len < sizeof(ip6)) + return false; + + /* BIG TCP/jumbograms won't work; netlink attr len is u16 / + if (ntohs(ip6->payload_len) != data_len - sizeof(ip6)) + return false; + + if (ip6->version != 6) + return false; + + return nfqnl_validate_exthdr(ip6, data_len, e); +} + +static bool nfqnl_validate_write(const void data, unsigned int data_len, + const struct nf_queue_entry e) +{ + switch (e->state.pf) { + case NFPROTO_IPV4: + return nfqnl_validate_ip4(data, data_len, e); + case NFPROTO_IPV6: + return nfqnl_validate_ip6(data, data_len, e) && + !(IP6CB(e->skb)->flags & IP6SKB_JUMBOGRAM); + case NFPROTO_BRIDGE: + /* No write support. Bridge is dubious: userspace doesn't even see L2 header / + return false; + } + + return false; +} + static int nfqnl_mangle(void data, unsigned int data_len, struct nf_queue_entry e, int diff) { @@ -1192,6 +1359,9 @@ nfqnl_mangle(void data, unsigned int data_len, struct nf_queue_entry e, int di if (e->state.net->user_ns != &init_user_ns) return -EPERM; + if (!nfqnl_validate_write(data, data_len, e)) + return -EINVAL; + if (diff < 0) { unsigned int min_len = skb_transport_offset(e->skb); diff --git a/net/netfilter/nft_fib.c b/net/netfilter/nft_fib.c index e048f05694cddd..89555380f1c5a0 100644 --- a/net/netfilter/nft_fib.c +++ b/net/netfilter/nft_fib.c @@ -31,6 +31,15 @@ int nft_fib_validate(const struct nft_ctx ctx, const struct nft_expr expr) const struct nft_fib priv = nft_expr_priv(expr); unsigned int hooks; + switch (ctx->family) { + case NFPROTO_IPV4: + case NFPROTO_IPV6: + case NFPROTO_INET: + break; + default: + return -EOPNOTSUPP; + } + switch (priv->result) { case NFT_FIB_RESULT_OIF: case NFT_FIB_RESULT_OIFNAME: diff --git a/net/netfilter/nft_fib_netdev.c b/net/netfilter/nft_fib_netdev.c index 3f3478abd84546..5774a754402780 100644 --- a/net/netfilter/nft_fib_netdev.c +++ b/net/netfilter/nft_fib_netdev.c @@ -50,6 +50,33 @@ static void nft_fib_netdev_eval(const struct nft_expr expr, regs->verdict.code = NFT_BREAK; } +static int nft_fib_netdev_validate(const struct nft_ctx ctx, + const struct nft_expr expr) +{ + const struct nft_fib priv = nft_expr_priv(expr); + unsigned int hooks; + + switch (priv->result) { + case NFT_FIB_RESULT_OIF: + case NFT_FIB_RESULT_OIFNAME: + hooks = (1 << NF_NETDEV_INGRESS); + break; + case NFT_FIB_RESULT_ADDRTYPE: + if (priv->flags & NFTA_FIB_F_IIF) + hooks = (1 << NF_NETDEV_INGRESS); + else if (priv->flags & NFTA_FIB_F_OIF) + hooks = (1 << NF_NETDEV_EGRESS); + else + hooks = (1 << NF_NETDEV_INGRESS) \| + (1 << NF_NETDEV_EGRESS); + break; + default: + return -EINVAL; + } + + return nft_chain_validate_hooks(ctx->chain, hooks); +} + static struct nft_expr_type nft_fib_netdev_type; static const struct nft_expr_ops nft_fib_netdev_ops = { .type = &nft_fib_netdev_type, @@ -57,7 +84,7 @@ static const struct nft_expr_ops nft_fib_netdev_ops = { .eval = nft_fib_netdev_eval, .init = nft_fib_init, .dump = nft_fib_dump, - .validate = nft_fib_validate, + .validate = nft_fib_netdev_validate, }; static struct nft_expr_type nft_fib_netdev_type __read_mostly = { diff --git a/net/netfilter/nft_payload.c b/net/netfilter/nft_payload.c index 345eff140d56f8..391539a1ceaa77 100644 --- a/net/netfilter/nft_payload.c +++ b/net/netfilter/nft_payload.c @@ -834,6 +834,249 @@ nft_payload_set_vlan(const u32 src, struct sk_buff skb, u16 offset, u8 len, return true; } +/* Ingress is very early, before l3 protocol handlers. + * There should be no in-tree code that trusts l3/l4 headers + * between ingress and NF_INET_PRE_ROUTING hooks. + / +static bool nft_in_ingress(const struct nf_hook_state s) +{ + return s->pf == NFPROTO_NETDEV && s->hook == NF_NETDEV_INGRESS; +} + +static bool nft_nh_write_ok_ip4(const struct nft_pktinfo pkt, + const struct nft_payload_set priv, + const u32 src) +{ + unsigned int offset = priv->offset + skb_network_offset(pkt->skb); + const u8 new_octets = (const u8 )src; + u8 old_octet; + + switch (priv->offset) { + case 0: / csum fixups does expand dscp/tos store to 2 bytes. + * make sure ihl/version remain unchanged. + / + if (skb_copy_bits(pkt->skb, offset, &old_octet, sizeof(old_octet))) + return false; + + return priv->len == 2 && + new_octets == old_octet; + case offsetof(struct iphdr, tos): + return priv->len == 1; + case offsetof(struct iphdr, id): + return priv->len == 2; + case offsetof(struct iphdr, ttl): + if (priv->len == 1) + return true; + + if (priv->len != 2) + return false; + + /* same, csum fixup does expand ttl store to two bytes. + * check protocol is not altered. + / + if (skb_copy_bits(pkt->skb, offset + 1, &old_octet, sizeof(old_octet))) + return false; + + return new_octets[1] == old_octet; + case offsetof(struct iphdr, check): + return priv->len <= 2 + 4 + 4; + case offsetof(struct iphdr, saddr): + return priv->len <= 4 + 4; + case offsetof(struct iphdr, daddr): + return priv->len <= 4; + } + + return false; +} + +static bool nft_nh_write_ok_ip6(const struct nft_pktinfo pkt, + const struct nft_payload_set priv, + const u32 src) +{ + const struct ipv6hdr ih = (const void )src; + + switch (priv->offset) { + case 0: /* store to dscp must not alter ip6 version / + return priv->len <= 4 && ih->version == 6; + case 2: + return priv->len <= 2; + case offsetof(struct ipv6hdr, hop_limit): + return priv->len == 1; + case offsetof(struct ipv6hdr, saddr): + return priv->len <= 16 + 16; + case offsetof(struct ipv6hdr, daddr): + return priv->len <= 16; + } + + return false; +} + +static bool nft_nh_write_ok_arp(const struct nft_payload_set priv) +{ + /* Variable size for standard ethernet arp / + const unsigned int eth_ip = 2 (ETH_ALEN + 4); + unsigned int offset = priv->offset; + + switch (offset) { + case offsetof(struct arphdr, ar_op): + return priv->len == 2; + default: + break; + } + + /* permit writes post fixed arp header size. offset + len are + * checked vs skb size via skb_ensure_writable. + / + return offset >= sizeof(struct arphdr) && priv->len <= eth_ip; +} + +static bool nft_nh_write_ok_netdev(const struct nft_pktinfo pkt, + const struct nft_payload_set priv, + const u32 src) +{ +#ifdef CONFIG_NF_TABLES_NETDEV + switch (pkt->skb->protocol) { + case htons(ETH_P_ARP): + return nft_nh_write_ok_arp(priv); + case htons(ETH_P_IP): + return nft_nh_write_ok_ip4(pkt, priv, src); + case htons(ETH_P_IPV6): + return nft_nh_write_ok_ip6(pkt, priv, src); + } +#endif + /* default to false for now, relax later in case we have + * use-cases that need inner header manipulation for + * encapsulated traffic like vlan or PPPoE. + / + return false; +} + +static bool nft_nh_write_ok_bridge(const struct nft_pktinfo pkt, + const struct nft_payload_set priv, + const u32 src) +{ +#if IS_ENABLED(CONFIG_NF_TABLES_BRIDGE) + switch (pkt->ethertype) { + case htons(ETH_P_ARP): + return nft_nh_write_ok_arp(priv); + case htons(ETH_P_IP): + return nft_nh_write_ok_ip4(pkt, priv, src); + case htons(ETH_P_IPV6): + return nft_nh_write_ok_ip6(pkt, priv, src); + } +#endif + /* see nft_nh_write_ok_netdev: default to false / + return false; +} + +static bool nft_nh_write_ok(const struct nft_pktinfo pkt, + const struct nft_payload_set priv, + const u32 src) +{ + switch (pkt->state->pf) { + case NFPROTO_ARP: + return nft_nh_write_ok_arp(priv); + case NFPROTO_BRIDGE: + return nft_nh_write_ok_bridge(pkt, priv, src); + case NFPROTO_IPV4: + return nft_nh_write_ok_ip4(pkt, priv, src); + case NFPROTO_IPV6: + return nft_nh_write_ok_ip6(pkt, priv, src); + case NFPROTO_NETDEV: + if (pkt->state->hook == NF_NETDEV_INGRESS) + return true; + return nft_nh_write_ok_netdev(pkt, priv, src); + } + + return false; +} + +/* check linklayer modifications don't spill into network header. / +static bool nft_ll_write_ok(const struct nft_pktinfo pkt, int offset) +{ + if (nft_in_ingress(pkt->state)) + return true; + + return offset <= skb_network_offset(pkt->skb); +} + +static bool nft_payload_validate_inet_csum_offset(const struct nft_ctx ctx, + const struct nft_payload_set priv) +{ + switch (priv->base) { + case NFT_PAYLOAD_LL_HEADER: + break; + case NFT_PAYLOAD_NETWORK_HEADER: + if (ctx->family == NFPROTO_IPV4) { + if (offsetof(struct iphdr, check) == priv->csum_offset) + return true; + + return false; + } + return true; /* run time validation required / + case NFT_PAYLOAD_TRANSPORT_HEADER: + if (priv->csum_flags) / makes no sense, asks for "re-update" of L4 checksum / + return false; + + / no further check here; offset can't be negative so bogus + * offsets can corrupt L4 or payload but not l3 headers. + * We already allow arbitrary l4/inner payload writes. + / + return true; + case NFT_PAYLOAD_INNER_HEADER: + return true; + case NFT_PAYLOAD_TUN_HEADER: + break; + } + + return false; +} + +/ do not allow arbitrary network header mangling via bogus csum_off. + * We only support ipv4. Only NFPROTO_IPV4 can be checked from control + * plane. + / +static bool nft_payload_csum_nh_write_ok(const struct nft_payload_set priv, + const struct nft_pktinfo pkt) +{ + switch (pkt->state->pf) { + case NFPROTO_IPV4: + / Warning: NFPROTO_INET was not checked; we can't return true here. / + return priv->csum_offset == offsetof(struct iphdr, check); + case NFPROTO_IPV6: + return false; + case NFPROTO_BRIDGE: + return pkt->ethertype == htons(ETH_P_IP) && + priv->csum_offset == offsetof(struct iphdr, check); + case NFPROTO_NETDEV: + return pkt->skb->protocol == htons(ETH_P_IP) && + priv->csum_offset == offsetof(struct iphdr, check); + } + + return false; +} + +static bool nft_payload_csum_write_ok(const struct nft_pktinfo pkt, + const struct nft_payload_set priv) +{ + switch (priv->base) { + case NFT_PAYLOAD_LL_HEADER: + break; + case NFT_PAYLOAD_NETWORK_HEADER: + return nft_payload_csum_nh_write_ok(priv, pkt); + case NFT_PAYLOAD_TRANSPORT_HEADER: + case NFT_PAYLOAD_INNER_HEADER: + / neither offsets are validated, offsets cannot be + * negative so real l3 headers cannot be mangled. + / + return true; + case NFT_PAYLOAD_TUN_HEADER: + break; + } + + return false; +} + static void nft_payload_set_eval(const struct nft_expr expr, struct nft_regs regs, const struct nft_pktinfo pkt) @@ -861,8 +1104,12 @@ static void nft_payload_set_eval(const struct nft_expr expr, } offset = skb_mac_header(skb) - skb->data - vlan_hlen; + if (!nft_ll_write_ok(pkt, priv->len + priv->offset + offset)) + goto err; break; case NFT_PAYLOAD_NETWORK_HEADER: + if (!nft_nh_write_ok(pkt, priv, src)) + goto err; offset = skb_network_offset(skb); break; case NFT_PAYLOAD_TRANSPORT_HEADER: @@ -894,6 +1141,7 @@ static void nft_payload_set_eval(const struct nft_expr expr, tsum = csum_partial(src, priv->len, 0); if (priv->csum_type == NFT_PAYLOAD_CSUM_INET && + nft_payload_csum_write_ok(pkt, priv) && nft_payload_csum_inet(skb, src, fsum, tsum, csum_offset)) goto err; @@ -960,7 +1208,26 @@ static int nft_payload_set_init(const struct nft_ctx ctx, switch (csum_type) { case NFT_PAYLOAD_CSUM_NONE: + if (priv->csum_offset) / nonsensical / + return -EINVAL; + + if (priv->csum_flags == 0) + break; + + / Userspace requests L4 checksum update, e.g.: + * - IPv6 stateless NAT (no l3 csum) + * - transport header mangling + * - inner data mangling + / + if (priv->base == NFT_PAYLOAD_NETWORK_HEADER \|\| + priv->base == NFT_PAYLOAD_TRANSPORT_HEADER \|\| + priv->base == NFT_PAYLOAD_INNER_HEADER) + break; + + return -EINVAL; case NFT_PAYLOAD_CSUM_INET: + if (!nft_payload_validate_inet_csum_offset(ctx, priv)) + return -EINVAL; break; case NFT_PAYLOAD_CSUM_SCTP: if (priv->base != NFT_PAYLOAD_TRANSPORT_HEADER) @@ -968,6 +1235,9 @@ static int nft_payload_set_init(const struct nft_ctx ctx, if (priv->csum_offset != offsetof(struct sctphdr, checksum)) return -EINVAL; + + if (priv->csum_flags) + return -EINVAL; break; default: return -EOPNOTSUPP; diff --git a/net/netfilter/nft_set_pipapo.c b/net/netfilter/nft_set_pipapo.c index 706c78853f245b..978bb0c0110682 100644 --- a/net/netfilter/nft_set_pipapo.c +++ b/net/netfilter/nft_set_pipapo.c @@ -342,6 +342,8 @@ #include "nft_set_pipapo_avx2.h" #include "nft_set_pipapo.h" +static void nft_pipapo_abort(const struct nft_set set); + /* * pipapo_refill() - For each set bit, set bits from selected mapping table item * @map: Bitmap to be scanned for set bits @@ -1296,7 +1298,7 @@ static int nft_pipapo_insert(const struct net net, const struct nft_set set, const u8 start_p, end_p; int i, bsize_max, err = 0; - if (!m) + if (!m \|\| m->state == NFT_PIPAPO_CLONE_ERR) return -ENOMEM; if (nft_set_ext_exists(ext, NFT_SET_EXT_KEY_END)) @@ -1367,8 +1369,10 @@ static int nft_pipapo_insert(const struct net net, const struct nft_set set, else ret = pipapo_expand(f, start, end, f->groups * f->bb); - if (ret < 0) - return ret; + if (ret < 0) { + err = ret; + goto abort; + } if (f->bsize > bsize_max) bsize_max = f->bsize; @@ -1384,7 +1388,7 @@ static int nft_pipapo_insert(const struct net net, const struct nft_set set, err = pipapo_realloc_scratch(m, bsize_max); if (err) - return err; + goto abort; m->bsize_max = bsize_max; } else { @@ -1396,7 +1400,26 @@ static int nft_pipapo_insert(const struct net net, const struct nft_set set, pipapo_map(m, rulemap, e); + m->state = NFT_PIPAPO_CLONE_MOD; return 0; +abort: + DEBUG_NET_WARN_ON_ONCE(m->state == NFT_PIPAPO_CLONE_ERR); + + /* Two rollback cases: + * 1) no previous changes. nft_pipapo_abort is not + * guaranteed to be invoked (there might be no further + * add/delete requests coming after this). + * + * 2) we had previous changes: there are transaction + * records pointing to this set. Leave the rollback to + * the transaction handling. + / + if (m->state == NFT_PIPAPO_CLONE_NEW) + nft_pipapo_abort(set); / releases m / + else + m->state = NFT_PIPAPO_CLONE_ERR; + + return err; } /* @@ -1473,6 +1496,7 @@ static struct nft_pipapo_match pipapo_clone(struct nft_pipapo_match old) dst++; } + new->state = NFT_PIPAPO_CLONE_NEW; return new; out_mt: @@ -1896,7 +1920,7 @@ nft_pipapo_deactivate(const struct net net, const struct nft_set set, /* removal must occur on priv->clone, if we are low on memory * we have no choice and must fail the removal request. / - if (!m) + if (!m \|\| m->state == NFT_PIPAPO_CLONE_ERR) return NULL; e = pipapo_get(m, (const u8 )elem->key.val.data, diff --git a/net/netfilter/nft_set_pipapo.h b/net/netfilter/nft_set_pipapo.h index b82abb03576edd..a19e980d06ef42 100644 --- a/net/netfilter/nft_set_pipapo.h +++ b/net/netfilter/nft_set_pipapo.h @@ -131,9 +131,16 @@ struct nft_pipapo_scratch { unsigned long __map[]; }; +enum nft_pipapo_clone_state { + NFT_PIPAPO_CLONE_NEW, + NFT_PIPAPO_CLONE_MOD, + NFT_PIPAPO_CLONE_ERR, +}; + /** * struct nft_pipapo_match - Data used for lookup and matching * @field_count: Amount of fields in set + * @state: add/delete state; used from control plane * @bsize_max: Maximum lookup table bucket size of all fields, in longs * @scratch: Preallocated per-CPU maps for partial matching results * @rcu: Matching data is swapped on commits @@ -141,6 +148,7 @@ struct nft_pipapo_scratch { / struct nft_pipapo_match { u8 field_count; + enum nft_pipapo_clone_state state:8; unsigned int bsize_max; struct nft_pipapo_scratch __percpu *scratch; struct rcu_head rcu;
3/2	2026/06/30 06:06	llm	patch-evaluator	0m Model: gemini-3.1-pro-preview Args: null Results: null Tokens: input: 11600 output: 34 thoughts: 608 Thoughts: Patch Series Evaluation: A Fuzzing Opportunity Okay, so I've got this patch series in front of me, and my immediate thought is yes, this deserves a thorough fuzzing campaign. It's touching quite a few critical areas of the `netfilter` subsystem: specifically, a dive into netlink queue, some changes to nftables payload mangling, the handling of pipapo sets, and conntrack expectations. Given the scope and the types of modifications, from locking changes in `ip_set_core.c` (that `rcu_read_lock`/`unlock` is interesting) to various initialization and validation adjustments across multiple files, the potential for subtle bugs is definitely there. It's clear that this touches on various core network filtering components. In `nf_conntrack_expect.c` the change to `zalloc` with added initialization raises immediate concerns. The changes related to the SIP helper (`nf_conntrack_sip.c`) sound important, as do the validations added in `nfnetlink_queue.c` and `nft_` files. The state tracking added to `nft_set_pipapo.c` looks like an area where subtle race conditions or unexpected state transitions could arise. Now, before we jump into the fuzzing, we need to make sure we've got the right kernel configurations enabled. Let's see... we'll definitely need `CONFIG_NETFILTER`, naturally. Beyond that, I'm thinking `CONFIG_NF_CONNTRACK`, `CONFIG_NF_CONNTRACK_SIP`, `CONFIG_NF_CT_NETLINK`, `CONFIG_NETFILTER_NETLINK_QUEUE`, `CONFIG_NF_TABLES`, and the `CONFIG_NFT_` options, so `CONFIG_NFT_FIB`, `CONFIG_NFT_FIB_NETDEV`, `CONFIG_NFT_PAYLOAD`, and I also saw some `IP_SET` references, so we need `CONFIG_IP_SET`. We must ensure these are enabled so the fuzzer can properly test these changes. I'll quickly do some code searching to verify these dependencies and then get the fuzzing environment setup. This looks like it'll be a fruitful fuzzing campaign!
4/2	2026/06/30 06:06	tool	grepper	0m Args: { "Expression": "config NF_CONNTRACK_SIP", "PathPrefix": "net/netfilter/Kconfig" } Results: { "Output": "net/netfilter/Kconfig=330=config NF_CONNTRACK_SANE\n--\nnet/netfilter/Kconfig-342-\nnet/netfilter/Kconfig:343:config NF_CONNTRACK_SIP\nnet/netfilter/Kconfig-344-\ttristate \"SIP protocol support\"\n" }
5/2	2026/06/30 06:06	llm	patch-evaluator	0m Model: gemini-3.1-pro-preview Args: null Results: null Tokens: input: 12805 output: 35 thoughts: 15 Thoughts: Okay, here's my interpretation of that thought process, assuming I'm deep in the weeds of kernel networking, maybe debugging a performance issue or setting up some advanced firewall rules: Netfilter and Netlink Queue Check Alright, before I dive too deep into this packet filtering mess, I need to make absolutely sure the basics are in place. The whole Netfilter setup relies heavily on the netlink queueing mechanism for user-space interaction. So, before I start pulling my hair out trying to debug some weird traffic behaviour or missing packets, let's just do a quick sanity check: I need to verify that `CONFIG_NETFILTER_NETLINK_QUEUE` is enabled. It's such a fundamental component, and I've been bitten by forgetting to check this before – wasting hours trying to figure out why my custom rules aren't being hit. This is my foundation; I need to make sure it's solid before building anything on top of it. One missing config option can derail the whole operation. Let's make sure that netlink queue is enabled, and then I can proceed.
6/2	2026/06/30 06:06	tool	grepper	0m Args: { "Expression": "config NETFILTER_NETLINK_QUEUE", "PathPrefix": "net/netfilter/Kconfig" } Results: { "Output": "net/netfilter/Kconfig=46=config NETFILTER_NETLINK_ACCT\n--\nnet/netfilter/Kconfig-53-\nnet/netfilter/Kconfig:54:config NETFILTER_NETLINK_QUEUE\nnet/netfilter/Kconfig-55-\ttristate \"Netfilter NFQUEUE over NFNETLINK interface\"\n" }
7/2	2026/06/30 06:06	llm	patch-evaluator	0m Model: gemini-3.1-pro-preview Args: null Results: null Tokens: input: 13178 output: 32 thoughts: 12 Thoughts: Here's my thought process, as requested: Checking `CONFIG_NFT_FIB` for Netfilter Functionality Okay, first things first, I need to verify if the `CONFIG_NFT_FIB` option is enabled. I know this is crucial for enabling the FIB (Forwarding Information Base) support within Netfilter's nftables framework. Without this, I won't have the necessary foundation for advanced routing and packet filtering capabilities that I'm likely trying to implement. I need to make sure this is enabled to proceed with whatever task is at hand. This is a foundational step, and neglecting it could lead to hours of wasted effort chasing phantom problems. Time to check the configuration...
8/2	2026/06/30 06:06	tool	grepper	0m Args: { "Expression": "config NFT_FIB", "PathPrefix": "net/netfilter/Kconfig" } Results: { "Output": "net/netfilter/Kconfig=599=config NFT_HASH\n--\nnet/netfilter/Kconfig-604-\nnet/netfilter/Kconfig:605:config NFT_FIB\nnet/netfilter/Kconfig-606-\ttristate\nnet/netfilter/Kconfig-607-\nnet/netfilter/Kconfig:608:config NFT_FIB_INET\nnet/netfilter/Kconfig-609-\tdepends on NF_TABLES_INET\n--\nnet/netfilter/Kconfig=674=config NFT_FWD_NETDEV\n--\nnet/netfilter/Kconfig-679-\nnet/netfilter/Kconfig:680:config NFT_FIB_NETDEV\nnet/netfilter/Kconfig-681-\tdepends on NFT_FIB_IPV4\n" }
9/2	2026/06/30 06:06	llm	patch-evaluator	0m Model: gemini-3.1-pro-preview Args: null Results: null Tokens: input: 13586 output: 32 thoughts: 12 Thoughts: Here's my take on those thoughts: Evaluating `CONFIG_NFT_PAYLOAD` Okay, so I'm thinking, let's just make sure we're on top of `CONFIG_NFT_PAYLOAD`. It's a key element, obviously. It dictates how we're going to interact with the payload within the context of nftables, and that's critical for our overall performance and security profile. Is this enabled? Is it correctly configured? Are there any dependencies I need to consider? I need to quickly assess its current status and make sure it aligns with the overall requirements of the system's intended behavior, particularly considering the network traffic analysis and manipulation that's going on here. It's a fundamental setting, so I want to ensure it's set up correctly.
10/2	2026/06/30 06:06	tool	grepper	0m Error: no matches Args: { "Expression": "config NFT_PAYLOAD", "PathPrefix": "net/netfilter/Kconfig" } Results: { "error": "no matches" }
11/2	2026/06/30 06:06	llm	patch-evaluator	0m Model: gemini-3.1-pro-preview Args: null Results: null Tokens: input: 13813 output: 29 thoughts: 46 Thoughts: Here's my thought process, summarized as you requested: Navigating the Netfilter Build Process Okay, so I'm digging into this `nft_payload.c` file and I'm pretty sure it's being compiled into the kernel conditionally, specifically depending on the Netfilter configuration. My intuition says `CONFIG_NF_TABLES` is likely the key trigger, but it could be something else entirely. I've got to confirm this. The most logical place to start digging would be the Netfilter `Makefile`, in `net/netfilter/`. That's where all the build rules for this stuff would be defined, so let's jump in there and see what the build process is actually doing with `nft_payload.c`. Hopefully, it'll be clear pretty quickly whether it's unconditionally built with a specific config or if there are other dependencies at play.
12/2	2026/06/30 06:06	tool	grepper	0m Args: { "Expression": "nft_payload", "PathPrefix": "net/netfilter/Makefile" } Results: { "Output": "net/netfilter/Makefile=87=nf_tables-objs := nf_tables_core.o nf_tables_api.o nft_chain_filter.o \\\nnet/netfilter/Makefile-88-\t\t nf_tables_trace.o nft_immediate.o nft_cmp.o nft_range.o \\\nnet/netfilter/Makefile:89:\t\t nft_bitwise.o nft_byteorder.o nft_payload.o nft_lookup.o \\\nnet/netfilter/Makefile-90-\t\t nft_dynset.o nft_meta.o nft_rt.o nft_exthdr.o nft_last.o \\\n" }
13/2	2026/06/30 06:06	llm	patch-evaluator	0m Model: gemini-3.1-pro-preview Args: null Results: null Tokens: input: 14240 output: 32 thoughts: 43 Thoughts: Okay, here's my interpretation of those thoughts, summarized from my perspective as an expert in the field: Assessing Configuration Dependencies Alright, so `nft_payload.o` is definitely a component within `nf_tables-objs`. That confirms that having `CONFIG_NF_TABLES` enabled covers the dependencies for that particular object file. No need to dig any deeper there. However, it looks like I should check on `nft_set_pipapo`. I need to assess what its dependencies are, and whether or not enabling `CONFIG_NF_TABLES` sufficiently addresses those too. I'm seeing it for the first time, and I need to determine if there are any other specific configurations I need to take care of in conjunction with the base `nf_tables` config.
14/2	2026/06/30 06:06	tool	grepper	0m Args: { "Expression": "nft_set_pipapo", "PathPrefix": "net/netfilter/Makefile" } Results: { "Output": "net/netfilter/Makefile=87=nf_tables-objs := nf_tables_core.o nf_tables_api.o nft_chain_filter.o \\\n--\nnet/netfilter/Makefile-93-\t\t nft_set_hash.o nft_set_bitmap.o nft_set_rbtree.o \\\nnet/netfilter/Makefile:94:\t\t nft_set_pipapo.o\nnet/netfilter/Makefile-95-\n--\nnet/netfilter/Makefile=97=ifndef CONFIG_UML\nnet/netfilter/Makefile:98:nf_tables-objs += nft_set_pipapo_avx2.o\nnet/netfilter/Makefile-99-endif\n" }
15/2	2026/06/30 06:06	llm	patch-evaluator	0m Model: gemini-3.1-pro-preview Args: null Results: null Tokens: input: 14662 output: 32 thoughts: 22 Thoughts: Here's my summary, as though I'm thinking through this myself: Considering Dependencies and Related Modules Okay, so I'm looking at this `nf_tables-objs` thing. Right, that's definitely a key component. But, I need to zoom out a bit. What else is in play here? Specifically, I'm wondering about `nfnetlink_cthelper`. Is it directly related? Is it a dependency? Or is it something that interacts with `nf_tables-objs` in some other significant way? I need to understand its role in the overall picture, if any. Digging into the relationships here will paint a better picture.
16/2	2026/06/30 06:06	tool	grepper	0m Args: { "Expression": "nfnetlink_cthelper", "PathPrefix": "net/netfilter/Makefile" } Results: { "Output": "net/netfilter/Makefile=38=obj-$(CONFIG_NF_CT_NETLINK_TIMEOUT) += nfnetlink_cttimeout.o\nnet/netfilter/Makefile:39:obj-$(CONFIG_NF_CT_NETLINK_HELPER) += nfnetlink_cthelper.o\nnet/netfilter/Makefile-40-\n" }
17/2	2026/06/30 06:06	llm	patch-evaluator	0m Model: gemini-3.1-pro-preview Args: null Results: null Tokens: input: 14950 output: 33 thoughts: 28 Thoughts: Okay, here's my take on those thoughts, framed as an expert's internal monologue: Navigating the Kernel Configuration Labyrinth Alright, so the task at hand requires `CONFIG_NF_CT_NETLINK_HELPER`. That's the baseline, the core functionality we need to get rolling. Now, before I dive too deep into the specific implementation, I'm going to take a moment to double-check something that often intersects with this area – specifically, `CONFIG_IP_SET`. It's a key piece of the puzzle, and often a prerequisite or at least a related feature. Let's make sure it’s enabled or at least understood in this context before I proceed. I need to understand its relationship to the netlink helper.
18/2	2026/06/30 06:06	tool	grepper	0m Args: { "Expression": "config IP_SET", "PathPrefix": "net/netfilter/ipset/Kconfig" } Results: { "Output": "net/netfilter/ipset/Kconfig-1-# SPDX-License-Identifier: GPL-2.0-only\nnet/netfilter/ipset/Kconfig:2:menuconfig IP_SET\nnet/netfilter/ipset/Kconfig-3-\ttristate \"IP set support\"\n--\nnet/netfilter/ipset/Kconfig=14=if IP_SET\nnet/netfilter/ipset/Kconfig-15-\nnet/netfilter/ipset/Kconfig:16:config IP_SET_MAX\nnet/netfilter/ipset/Kconfig-17-\tint \"Maximum number of IP sets\"\n--\nnet/netfilter/ipset/Kconfig-27-\nnet/netfilter/ipset/Kconfig:28:config IP_SET_BITMAP_IP\nnet/netfilter/ipset/Kconfig-29-\ttristate \"bitmap:ip set support\"\n--\nnet/netfilter/ipset/Kconfig-36-\nnet/netfilter/ipset/Kconfig:37:config IP_SET_BITMAP_IPMAC\nnet/netfilter/ipset/Kconfig-38-\ttristate \"bitmap:ip,mac set support\"\n--\nnet/netfilter/ipset/Kconfig-45-\nnet/netfilter/ipset/Kconfig:46:config IP_SET_BITMAP_PORT\nnet/netfilter/ipset/Kconfig-47-\ttristate \"bitmap:port set support\"\n--\nnet/netfilter/ipset/Kconfig-54-\nnet/netfilter/ipset/Kconfig:55:config IP_SET_HASH_IP\nnet/netfilter/ipset/Kconfig-56-\ttristate \"hash:ip set support\"\n--\nnet/netfilter/ipset/Kconfig-64-\nnet/netfilter/ipset/Kconfig:65:config IP_SET_HASH_IPMARK\nnet/netfilter/ipset/Kconfig-66-\ttristate \"hash:ip,mark set support\"\n--\nnet/netfilter/ipset/Kconfig-73-\nnet/netfilter/ipset/Kconfig:74:config IP_SET_HASH_IPPORT\nnet/netfilter/ipset/Kconfig-75-\ttristate \"hash:ip,port set support\"\n--\nnet/netfilter/ipset/Kconfig-82-\nnet/netfilter/ipset/Kconfig:83:config IP_SET_HASH_IPPORTIP\nnet/netfilter/ipset/Kconfig-84-\ttristate \"hash:ip,port,ip set support\"\n--\nnet/netfilter/ipset/Kconfig-92-\nnet/netfilter/ipset/Kconfig:93:config IP_SET_HASH_IPPORTNET\nnet/netfilter/ipset/Kconfig-94-\ttristate \"hash:ip,port,net set support\"\n--\nnet/netfilter/ipset/Kconfig-102-\nnet/netfilter/ipset/Kconfig:103:config IP_SET_HASH_IPMAC\nnet/netfilter/ipset/Kconfig-104-\ttristate \"hash:ip,mac set support\"\n--\nnet/netfilter/ipset/Kconfig-111-\nnet/netfilter/ipset/Kconfig:112:config IP_SET_HASH_MAC\nnet/netfilter/ipset/Kconfig-113-\ttristate \"hash:mac set support\"\n--\nnet/netfilter/ipset/Kconfig-120-\nnet/netfilter/ipset/Kconfig:121:config IP_SET_HASH_NETPORTNET\nnet/netfilter/ipset/Kconfig-122-\ttristate \"hash:net,port,net set support\"\n--\nnet/netfilter/ipset/Kconfig-129-\nnet/netfilter/ipset/Kconfig:130:config IP_SET_HASH_NET\nnet/netfilter/ipset/Kconfig-131-\ttristate \"hash:net set support\"\n--\nnet/netfilter/ipset/Kconfig-138-\nnet/netfilter/ipset/Kconfig:139:config IP_SET_HASH_NETNET\nnet/netfilter/ipset/Kconfig-140-\ttristate \"hash:net,net set support\"\n--\nnet/netfilter/ipset/Kconfig-147-\nnet/netfilter/ipset/Kconfig:148:config IP_SET_HASH_NETPORT\nnet/netfilter/ipset/Kconfig-149-\ttristate \"hash:net,port set support\"\n--\nnet/netfilter/ipset/Kconfig-157-\nnet/netfilter/ipset/Kconfig:158:config IP_SET_HASH_NETIFACE\nnet/netfilter/ipset/Kconfig-159-\ttristate \"hash:net,iface set support\"\n--\nnet/netfilter/ipset/Kconfig-167-\nnet/netfilter/ipset/Kconfig:168:config IP_SET_LIST_SET\nnet/netfilter/ipset/Kconfig-169-\ttristate \"list:set set support\"\n" }
19/2	2026/06/30 06:06	llm	patch-evaluator	0m Model: gemini-3.1-pro-preview Args: null Results: null Tokens: input: 16401 output: 33 thoughts: 59 Thoughts: Okay, here's my take on those config considerations, distilled into my internal thought process: Kernel Configuration Dependencies Alright, looks like `CONFIG_IP_SET` is a hard requirement. Got it. Now, I need to double-check something related to connection tracking, specifically expectations. My instinct is telling me that `CONFIG_NF_CONNTRACK_EXPECT` might be involved. However, I need to be sure. I believe that expectations are a core part of the base `CONFIG_NF_CONNTRACK` module. Now, the question is, is there a distinct configuration option tied directly to the `nf_conntrack_expect.c` module within the kernel source? I need to verify its exact configuration path. It might be part of another configuration or it could be a separate option. I'll need to drill down and see if there are any specific options to be aware of.
20/2	2026/06/30 06:06	tool	grepper	0m Args: { "Expression": "nf_conntrack_expect", "PathPrefix": "net/netfilter/Makefile" } 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 \\\n" }
21/2	2026/06/30 06:06	llm	patch-evaluator	0m Model: gemini-3.1-pro-preview Args: null Results: null Tokens: input: 16843 output: 34 thoughts: 31 Thoughts: Okay, here's my interpretation of those thoughts, presented as a first-person expert summary: Connecting the Dots in Netfilter Conntrack Alright, so the initial clue points directly to `nf_conntrack-y`. That's a strong indicator. Now, the next logical step is to confirm the presence and configuration of `CONFIG_NF_CT_NETLINK`. This is where the core interaction with userspace happens for `nf_conntrack`. I need to ensure that the necessary netlink interface is enabled. If this configuration option isn't set, then the ability to interact with the conntrack table from userspace via netlink won't be available, and that would cause certain behaviors, specifically in certain network management tools, to fail as expected. This also helps to ensure the expected performance characteristics. I suspect this is the key piece of the puzzle.
22/2	2026/06/30 06:06	tool	grepper	0m Args: { "Expression": "config NF_CT_NETLINK", "PathPrefix": "net/netfilter/Kconfig" } Results: { "Output": "net/netfilter/Kconfig=355=config NF_CONNTRACK_TFTP\n--\nnet/netfilter/Kconfig-365-\nnet/netfilter/Kconfig:366:config NF_CT_NETLINK\nnet/netfilter/Kconfig-367-\ttristate 'Connection tracking netlink interface'\n--\nnet/netfilter/Kconfig-372-\nnet/netfilter/Kconfig:373:config NF_CT_NETLINK_TIMEOUT\nnet/netfilter/Kconfig-374-\ttristate 'Connection tracking timeout tuning via Netlink'\n--\nnet/netfilter/Kconfig-384-\nnet/netfilter/Kconfig:385:config NF_CT_NETLINK_HELPER\nnet/netfilter/Kconfig-386-\ttristate 'Connection tracking helpers in user-space via Netlink'\n" }
23/2	2026/06/30 06:06	llm	patch-evaluator	0m Model: gemini-3.1-pro-preview Args: null Results: null Tokens: input: 17317 output: 112 thoughts: 839 Thoughts: Fuzzing Focus Refinement Okay, so I've been taking a look at a few areas within the Netfilter/iptables code, trying to pinpoint good candidates for fuzzing. I've got a fairly comprehensive list of modules to consider: `NF_CONNTRACK`, `NF_CONNTRACK_SIP`, `NF_CT_NETLINK`, `NF_CT_NETLINK_HELPER`, `NETFILTER_NETLINK_QUEUE`, `NF_TABLES`, `NFT_FIB`, `NFT_FIB_NETDEV`, and `IP_SET`. A wide variety. Now, my initial thought is to dive into functions that handle netlink interactions, packet processing, and those that deal with stateful connections, those areas are ripe with complexity and potential vulnerabilities. I started by looking at `ip_set_core.c` and found `ip_set_dump_do`, since its netlink dump callback, so that's a decent start. Then I looked at `nf_conntrack_expect.c` and `nf_conntrack_netlink.c`, which offered `ctnetlink_alloc_expect` and found some functions in `nf_conntrack_sip.c` like `set_expected_rtp_rtcp`, which could be useful. `nfnetlink_cthelper.c` and `nfnetlink_queue.c` are also interesting. I saw `nfnl_cthelper_expect_policy`, and `nfqnl_mangle` in `nfnetlink_queue.c` that seems like a good target. It's handling packet manipulation, which is often a source of bugs. The `nfqnl_mangle` symbol is especially promising given its role in altering packets. The `nft_fib.c` and `nft_fib_netdev.c` code offers `nft_fib_validate` and `nft_fib_netdev_validate`, and they are also looking like potential targets. In `nft_payload.c`, I saw some initializations and evaluations; `nft_payload_set_init` and `nft_payload_set_eval` seem like they should be investigated. I'm also looking into `nft_set_pipapo.c` and found `nft_pipapo_insert` and `pipapo_clone` as candidates too. So, let's refine this list, focusing on the most promising ones: `ip_set_dump_do`, `ctnetlink_alloc_expect`, `set_expected_rtp_rtcp`, `nfnl_cthelper_expect_policy`, `nfqnl_mangle`, `nft_fib_validate`, `nft_fib_netdev_validate`, `nft_payload_set_init`, `nft_payload_set_eval`, `nft_pipapo_insert`, and `pipapo_clone`. Now it's time to check if these are exported symbols and if they are even suitable for fuzzing in practice.
24/2	2026/06/30 06:07	tool	grepper	0m Args: { "Expression": "(ip_set_dump_do\|ctnetlink_alloc_expect\|set_expected_rtp_rtcp\|nfnl_cthelper_expect_policy\|nfqnl_mangle\|nft_fib_validate\|nft_fib_netdev_validate\|nft_payload_set_init\|nft_payload_set_eval\|nft_pipapo_insert\|pipapo_clone)", "PathPrefix": "net/netfilter/" } Results: { "Output": "net/netfilter/ipset/ip_set_core.c=1476=static int\nnet/netfilter/ipset/ip_set_core.c:1477:ip_set_dump_done(struct netlink_callback cb)\nnet/netfilter/ipset/ip_set_core.c-1478-{\n--\nnet/netfilter/ipset/ip_set_core.c=1570=static int\nnet/netfilter/ipset/ip_set_core.c:1571:ip_set_dump_do(struct sk_buff skb, struct netlink_callback cb)\nnet/netfilter/ipset/ip_set_core.c-1572-{\n--\nnet/netfilter/ipset/ip_set_core.c=1712=static int ip_set_dump(struct sk_buff skb, const struct nfnl_info info,\n--\nnet/netfilter/ipset/ip_set_core.c-1720-\t\t\t.start = ip_set_dump_start,\nnet/netfilter/ipset/ip_set_core.c:1721:\t\t\t.dump = ip_set_dump_do,\nnet/netfilter/ipset/ip_set_core.c:1722:\t\t\t.done = ip_set_dump_done,\nnet/netfilter/ipset/ip_set_core.c-1723-\t\t};\n--\nnet/netfilter/nf_conntrack_netlink.c=2630=static struct nf_conntrack_expect \nnet/netfilter/nf_conntrack_netlink.c:2631:ctnetlink_alloc_expect(const struct nlattr const cda[], struct nf_conn ct,\nnet/netfilter/nf_conntrack_netlink.c-2632-\t\t const struct nf_conntrack_helper assign_helper,\n--\nnet/netfilter/nf_conntrack_netlink.c=2856=ctnetlink_glue_attach_expect(const struct nlattr attr, struct nf_conn ct,\n--\nnet/netfilter/nf_conntrack_netlink.c-2887-\nnet/netfilter/nf_conntrack_netlink.c:2888:\texp = ctnetlink_alloc_expect((const struct nlattr const )cda, ct,\nnet/netfilter/nf_conntrack_netlink.c-2889-\t\t\t\t assign_helper, \u0026tuple, \u0026mask);\n--\nnet/netfilter/nf_conntrack_netlink.c=3519=static struct nf_conntrack_expect \nnet/netfilter/nf_conntrack_netlink.c:3520:ctnetlink_alloc_expect(const struct nlattr * const cda[], struct nf_conn ct,\nnet/netfilter/nf_conntrack_netlink.c-3521-\t\t const struct nf_conntrack_helper assign_helper,\n--\nnet/netfilter/nf_conntrack_netlink.c=3591=ctnetlink_create_expect(struct net net,\n--\nnet/netfilter/nf_conntrack_netlink.c-3622-\trcu_read_lock();\nnet/netfilter/nf_conntrack_netlink.c:3623:\texp = ctnetlink_alloc_expect(cda, ct, NULL, \u0026tuple, \u0026mask);\nnet/netfilter/nf_conntrack_netlink.c-3624-\tif (IS_ERR(exp)) {\n--\nnet/netfilter/nf_conntrack_sip.c=909=static void flush_expectations(struct nf_conn ct, bool media)\n--\nnet/netfilter/nf_conntrack_sip.c-928-\nnet/netfilter/nf_conntrack_sip.c:929:static int set_expected_rtp_rtcp(struct sk_buff skb, unsigned int protoff,\nnet/netfilter/nf_conntrack_sip.c-930-\t\t\t\t unsigned int dataoff,\n--\nnet/netfilter/nf_conntrack_sip.c=1116=static int process_sdp(struct sk_buff skb, unsigned int protoff,\n--\nnet/netfilter/nf_conntrack_sip.c-1198-\nnet/netfilter/nf_conntrack_sip.c:1199:\t\tret = set_expected_rtp_rtcp(skb, protoff, dataoff,\nnet/netfilter/nf_conntrack_sip.c-1200-\t\t\t\t\t dptr, datalen,\n--\nnet/netfilter/nfnetlink_cthelper.c=145=static int\nnet/netfilter/nfnetlink_cthelper.c:146:nfnl_cthelper_expect_policy(struct nf_conntrack_expect_policy expect_policy,\nnet/netfilter/nfnetlink_cthelper.c-147-\t\t\t const struct nlattr attr)\n--\nnet/netfilter/nfnetlink_cthelper.c=177=static const struct nla_policy\nnet/netfilter/nfnetlink_cthelper.c:178:nfnl_cthelper_expect_policy_set[NFCTH_POLICY_SET_MAX+1] = {\nnet/netfilter/nfnetlink_cthelper.c-179-\t[NFCTH_POLICY_SET_NUM] = NLA_POLICY_MAX(NLA_BE32, NF_CT_MAX_EXPECT_CLASSES),\n--\nnet/netfilter/nfnetlink_cthelper.c=183=nfnl_cthelper_parse_expect_policy(struct nf_conntrack_helper helper,\n--\nnet/netfilter/nfnetlink_cthelper.c-190-\tret = nla_parse_nested_deprecated(tb, NFCTH_POLICY_SET_MAX, attr,\nnet/netfilter/nfnetlink_cthelper.c:191:\t\t\t\t\t nfnl_cthelper_expect_policy_set,\nnet/netfilter/nfnetlink_cthelper.c-192-\t\t\t\t\t NULL);\n--\nnet/netfilter/nfnetlink_cthelper.c-208-\nnet/netfilter/nfnetlink_cthelper.c:209:\t\tret = nfnl_cthelper_expect_policy(\u0026helper-\u003eexpect_policy[i],\nnet/netfilter/nfnetlink_cthelper.c-210-\t\t\t\t\t\t tb[NFCTH_POLICY_SET+i]);\n--\nnet/netfilter/nfnetlink_cthelper.c=368=static int nfnl_cthelper_update_policy(struct nf_conntrack_helper helper,\n--\nnet/netfilter/nfnetlink_cthelper.c-375-\terr = nla_parse_nested_deprecated(tb, NFCTH_POLICY_SET_MAX, attr,\nnet/netfilter/nfnetlink_cthelper.c:376:\t\t\t\t\t nfnl_cthelper_expect_policy_set,\nnet/netfilter/nfnetlink_cthelper.c-377-\t\t\t\t\t NULL);\n--\nnet/netfilter/nfnetlink_queue.c=1354=static int\nnet/netfilter/nfnetlink_queue.c:1355:nfqnl_mangle(void data, unsigned int data_len, struct nf_queue_entry e, int diff)\nnet/netfilter/nfnetlink_queue.c-1356-{\n--\nnet/netfilter/nfnetlink_queue.c=1711=static int nfqnl_recv_verdict(struct sk_buff skb, const struct nfnl_info info,\n--\nnet/netfilter/nfnetlink_queue.c-1760-\nnet/netfilter/nfnetlink_queue.c:1761:\t\tif (nfqnl_mangle(nla_data(nfqa[NFQA_PAYLOAD]),\nnet/netfilter/nfnetlink_queue.c-1762-\t\t\t\t payload_len, entry, diff) \u003c 0)\n--\nnet/netfilter/nft_fib.c=27=EXPORT_SYMBOL(nft_fib_policy);\nnet/netfilter/nft_fib.c-28-\nnet/netfilter/nft_fib.c:29:int nft_fib_validate(const struct nft_ctx ctx, const struct nft_expr expr)\nnet/netfilter/nft_fib.c-30-{\n--\nnet/netfilter/nft_fib.c-72-}\nnet/netfilter/nft_fib.c:73:EXPORT_SYMBOL_GPL(nft_fib_validate);\nnet/netfilter/nft_fib.c-74-\n--\nnet/netfilter/nft_fib_inet.c=45=static const struct nft_expr_ops nft_fib_inet_ops = {\n--\nnet/netfilter/nft_fib_inet.c-50-\t.dump\t\t= nft_fib_dump,\nnet/netfilter/nft_fib_inet.c:51:\t.validate\t= nft_fib_validate,\nnet/netfilter/nft_fib_inet.c-52-};\n--\nnet/netfilter/nft_fib_netdev.c=21=static void nft_fib_netdev_eval(const struct nft_expr expr,\n--\nnet/netfilter/nft_fib_netdev.c-52-\nnet/netfilter/nft_fib_netdev.c:53:static int nft_fib_netdev_validate(const struct nft_ctx ctx,\nnet/netfilter/nft_fib_netdev.c-54-\t\t\t\t const struct nft_expr expr)\n--\nnet/netfilter/nft_fib_netdev.c=81=static const struct nft_expr_ops nft_fib_netdev_ops = {\n--\nnet/netfilter/nft_fib_netdev.c-86-\t.dump\t\t= nft_fib_dump,\nnet/netfilter/nft_fib_netdev.c:87:\t.validate\t= nft_fib_netdev_validate,\nnet/netfilter/nft_fib_netdev.c-88-};\n--\nnet/netfilter/nft_payload.c=1059=static bool nft_payload_csum_write_ok(const struct nft_pktinfo pkt,\n--\nnet/netfilter/nft_payload.c-1079-\nnet/netfilter/nft_payload.c:1080:static void nft_payload_set_eval(const struct nft_expr expr,\nnet/netfilter/nft_payload.c-1081-\t\t\t\t struct nft_regs regs,\n--\nnet/netfilter/nft_payload.c-1169-\nnet/netfilter/nft_payload.c:1170:static int nft_payload_set_init(const struct nft_ctx ctx,\nnet/netfilter/nft_payload.c-1171-\t\t\t\tconst struct nft_expr expr,\n--\nnet/netfilter/nft_payload.c=1271=static const struct nft_expr_ops nft_payload_set_ops = {\n--\nnet/netfilter/nft_payload.c-1273-\t.size\t\t= NFT_EXPR_SIZE(sizeof(struct nft_payload_set)),\nnet/netfilter/nft_payload.c:1274:\t.eval\t\t= nft_payload_set_eval,\nnet/netfilter/nft_payload.c:1275:\t.init\t\t= nft_payload_set_init,\nnet/netfilter/nft_payload.c-1276-\t.dump\t\t= nft_payload_set_dump,\n--\nnet/netfilter/nft_set_pipapo.c=1243=static bool nft_pipapo_transaction_mutex_held(const struct nft_set set)\n--\nnet/netfilter/nft_set_pipapo.c-1253-\nnet/netfilter/nft_set_pipapo.c:1254:static struct nft_pipapo_match pipapo_clone(struct nft_pipapo_match old);\nnet/netfilter/nft_set_pipapo.c-1255-\n--\nnet/netfilter/nft_set_pipapo.c=1262=static struct nft_pipapo_match pipapo_maybe_clone(const struct nft_set set)\n--\nnet/netfilter/nft_set_pipapo.c-1271-\t\t\t\t nft_pipapo_transaction_mutex_held(set));\nnet/netfilter/nft_set_pipapo.c:1272:\tpriv-\u003eclone = pipapo_clone(m);\nnet/netfilter/nft_set_pipapo.c-1273-\n--\nnet/netfilter/nft_set_pipapo.c-1277-/\nnet/netfilter/nft_set_pipapo.c:1278: nft_pipapo_insert() - Validate and insert ranged elements\nnet/netfilter/nft_set_pipapo.c-1279- * @net:\tNetwork namespace\n--\nnet/netfilter/nft_set_pipapo.c-1285- /\nnet/netfilter/nft_set_pipapo.c:1286:static int nft_pipapo_insert(const struct net net, const struct nft_set set,\nnet/netfilter/nft_set_pipapo.c-1287-\t\t\t const struct nft_set_elem elem,\n--\nnet/netfilter/nft_set_pipapo.c-1425-/*\nnet/netfilter/nft_set_pipapo.c:1426: pipapo_clone() - Clone matching data to create new working copy\nnet/netfilter/nft_set_pipapo.c-1427- * @old:\tExisting matching data\n--\nnet/netfilter/nft_set_pipapo.c-1430- /\nnet/netfilter/nft_set_pipapo.c:1431:static struct nft_pipapo_match pipapo_clone(struct nft_pipapo_match old)\nnet/netfilter/nft_set_pipapo.c-1432-{\n--\nnet/netfilter/nft_set_pipapo.c=1875=static void nft_pipapo_abort(const struct nft_set set)\n--\nnet/netfilter/nft_set_pipapo.c-1892- * in use for lookups, and not directly inserted into current lookup data. Both\nnet/netfilter/nft_set_pipapo.c:1893: * nft_pipapo_insert() and nft_pipapo_activate() are called once for each\nnet/netfilter/nft_set_pipapo.c-1894- * element, hence we can't purpose either one as a real commit operation.\n--\nnet/netfilter/nft_set_pipapo.c=2418=const struct nft_set_type nft_set_pipapo_type = {\n--\nnet/netfilter/nft_set_pipapo.c-2422-\t\t.lookup\t\t= nft_pipapo_lookup,\nnet/netfilter/nft_set_pipapo.c:2423:\t\t.insert\t\t= nft_pipapo_insert,\nnet/netfilter/nft_set_pipapo.c-2424-\t\t.activate\t= nft_pipapo_activate,\n--\nnet/netfilter/nft_set_pipapo.c=2443=const struct nft_set_type nft_set_pipapo_avx2_type = {\n--\nnet/netfilter/nft_set_pipapo.c-2447-\t\t.lookup\t\t= nft_pipapo_avx2_lookup,\nnet/netfilter/nft_set_pipapo.c:2448:\t\t.insert\t\t= nft_pipapo_insert,\nnet/netfilter/nft_set_pipapo.c-2449-\t\t.activate\t= nft_pipapo_activate,\n--\nnet/netfilter/nft_set_pipapo.h=128=struct nft_pipapo_scratch {\n--\nnet/netfilter/nft_set_pipapo.h-133-\nnet/netfilter/nft_set_pipapo.h:134:enum nft_pipapo_clone_state {\nnet/netfilter/nft_set_pipapo.h-135-\tNFT_PIPAPO_CLONE_NEW,\n--\nnet/netfilter/nft_set_pipapo.h=149=struct nft_pipapo_match {\nnet/netfilter/nft_set_pipapo.h-150-\tu8 field_count;\nnet/netfilter/nft_set_pipapo.h:151:\tenum nft_pipapo_clone_state state:8;\nnet/netfilter/nft_set_pipapo.h-152-\tunsigned int bsize_max;\n" }
25/2	2026/06/30 06:07	llm	patch-evaluator	0m Model: gemini-3.1-pro-preview Args: null Results: null Tokens: input: 23085 output: 32 thoughts: 963 Thoughts: Refining the Relevant Symbols and Configurations Okay, let's break this down. My initial focus was on identifying the key function symbols impacted by these changes. I started with a broader list: `ip_set_dump_do`, `ctnetlink_alloc_expect`, `set_expected_rtp_rtcp`, `nfnl_cthelper_expect_policy`, `nfqnl_mangle`, `nft_fib_validate`, `nft_fib_netdev_validate`, `nft_payload_set_init`, `nft_payload_set_eval`, `nft_pipapo_insert`, and `pipapo_clone`. Then, I started refining this list. I realized that several of those are static and used within other static functions. So, I need to focus on the ones with broader implications or that represent the public interface. That led me to consider a second set: `ip_set_dump_done`, `nf_ct_expect_alloc`, `nf_ct_expect_init`, `nfqnl_validate_write`, and expanded it again. I know I have to cover the core changes. Now, I'm thinking of a concise, representative list that avoids the most hot-path functions, but captures the essence of the changes. The final list includes: `ip_set_dump_done`, `ip_set_dump_do`, `ctnetlink_alloc_expect`, `set_expected_rtp_rtcp`, `nfnl_cthelper_expect_policy`, `nfqnl_mangle`, `nft_fib_validate`, `nft_fib_netdev_validate`, `nft_payload_set_init`, `nft_payload_set_eval`, and `nft_pipapo_insert`. Next, I need to analyze the relevant configurations. The initial list I had was: `NF_CONNTRACK`, `NF_CONNTRACK_SIP`, `NF_CT_NETLINK`, `NF_CT_NETLINK_HELPER`, `NETFILTER_NETLINK_QUEUE`, `NF_TABLES`, `NFT_FIB`, `NFT_FIB_NETDEV`, and `IP_SET`. I have to double-check that they are the right ones. I checked `NF_CONNTRACK_EXPECT` and the source files included. That made me consider how `NFT_FIB_NETDEV` related to `NF_TABLES`. And I checked `NFT_PIPAPO` too. I am satisfied the configurations listed are the right set of relevant configurations.
26/2	2026/06/30 06:07	tool	grepper	0m Args: { "Expression": "config NF_CONNTRACK", "PathPrefix": "net/netfilter/Kconfig" } 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" }
27/2	2026/06/30 06:07	llm	patch-evaluator	0m Model: gemini-3.1-pro-preview Args: null Results: null Tokens: input: 25923 output: 32 thoughts: 14 Thoughts: Okay, here's my take on those thoughts, tailored for an expert audience: Initial Assessment and Deep Dive Alright, initial impression: things seem to be in order. The overall architecture and design are presenting well. Before getting too far ahead, I'm thinking let's pivot to the nitty-gritty and focus our attention specifically on the `NF_TABLES` implementation. That's the core of the system, that's where the real logic lives. We'll examine the table configurations, chain definitions, rulesets, and how everything is connected. That level of detail is critical for catching potential subtle issues, optimizations, or unexpected behavior. No assumptions; it's time to dig in.
28/2	2026/06/30 06:07	tool	grepper	0m Args: { "Expression": "config NF_TABLES", "PathPrefix": "net/netfilter/Kconfig" } Results: { "Output": "net/netfilter/Kconfig=453=endif # NF_CONNTRACK\nnet/netfilter/Kconfig-454-\nnet/netfilter/Kconfig:455:config NF_TABLES\nnet/netfilter/Kconfig-456-\tselect NETFILTER_NETLINK\n--\nnet/netfilter/Kconfig=471=if NF_TABLES\nnet/netfilter/Kconfig:472:config NF_TABLES_INET\nnet/netfilter/Kconfig-473-\tdepends on IPV6\n--\nnet/netfilter/Kconfig-479-\nnet/netfilter/Kconfig:480:config NF_TABLES_NETDEV\nnet/netfilter/Kconfig-481-\tbool \"Netfilter nf_tables netdev tables support\"\n" }
29/2	2026/06/30 06:07	llm	patch-evaluator	0m Model: gemini-3.1-pro-preview Args: null Results: null Tokens: input: 26323 output: 35 thoughts: 91 Thoughts: Checking Dependencies for Network Filtering Features Okay, I need to make a quick addition to ensure broad compatibility. I should proactively include `NF_TABLES_NETDEV` and `NF_TABLES_INET` in my configuration just to be safe. It's possible that `nft_fib_netdev.c` and `nft_fib_inet.c` might have dependencies on them, and I don't want to run into any unexpected issues later. Now, hold on, I recall that `nft_fib_netdev.c` specifically relies on `NFT_FIB_NETDEV`. Alright, so that's the key. Let me immediately check the dependencies for `NFT_FIB_NETDEV` to confirm everything is in order and that I'm covering all the bases. I need to make sure this is all set up correctly before I continue.
30/2	2026/06/30 06:07	tool	grepper	0m Args: { "Expression": "config NFT_FIB_NETDEV", "PathPrefix": "net/netfilter/Kconfig" } Results: { "Output": "net/netfilter/Kconfig=674=config NFT_FWD_NETDEV\n--\nnet/netfilter/Kconfig-679-\nnet/netfilter/Kconfig:680:config NFT_FIB_NETDEV\nnet/netfilter/Kconfig-681-\tdepends on NFT_FIB_IPV4\n" }
31/2	2026/06/30 06:07	llm	patch-evaluator	0m Model: gemini-3.1-pro-preview Args: null Results: null Tokens: input: 26726 output: 38 thoughts: 26 Thoughts: Here's my take on those thoughts, assuming I'm an expert: Investigating the Need for `NFT_FIB_IPV4` Okay, so we're talking about `NFT_FIB_IPV4`. That's a key element in the `nftables` framework related to IPV4 forwarding information base (FIB) lookups. Essentially, it deals with routing decisions. The fact that it's even coming up suggests we're dealing with a situation where traditional routing tables are either inadequate or we're looking for something more sophisticated. My initial thought is that we're either building some kind of custom routing logic, implementing policy-based routing, or perhaps trying to optimize performance in a highly specific network scenario. The inclusion of the "FIB" is a red flag in the best way, and suggests we're working with something relatively low-level. I'll need to dig into the context to understand why this specific module is required, but first, I'm going to take a closer look at `NFT_FIB_IPV4` to confirm exactly what functionality it provides and what design decisions were made, so I can start to understand its function in the wider context.
32/2	2026/06/30 06:07	tool	grepper	0m Args: { "Expression": "config NFT_FIB_IPV4", "PathPrefix": "net/ipv4/netfilter/Kconfig" } Results: { "Output": "net/ipv4/netfilter/Kconfig=47=config NFT_DUP_IPV4\n--\nnet/ipv4/netfilter/Kconfig-53-\nnet/ipv4/netfilter/Kconfig:54:config NFT_FIB_IPV4\nnet/ipv4/netfilter/Kconfig-55-\tselect NFT_FIB\n" }
33/2	2026/06/30 06:07	llm	patch-evaluator	0m Model: gemini-3.1-pro-preview Args: null Results: null Tokens: input: 27142 output: 38 thoughts: 13 Thoughts: Okay, here's my attempt at summarizing that thought process, keeping in mind I'm speaking to a fellow expert: Investigating `NFT_FIB_IPV6` Alright, time to dive in. My initial thought is, "Let's check `NFT_FIB_IPV6`." Given the context, this likely means I'm troubleshooting, analyzing, or perhaps optimizing a network setup that involves IPv6 routing and forwarding tables. The specific naming convention immediately tells me we're likely using `nftables` (or the older `iptables` with some compatibility layers). I'm probably looking at a potential performance bottleneck, a misconfigured rule, or maybe trying to understand the current state of a complex firewall/routing setup. The fact that I'm specifically targeting the IPv6 FIB indicates a clear focus on the IPv6 portion of the network architecture. Let's get to it.
34/2	2026/06/30 06:07	tool	grepper	0m Args: { "Expression": "config NFT_FIB_IPV6", "PathPrefix": "net/ipv6/netfilter/Kconfig" } Results: { "Output": "net/ipv6/netfilter/Kconfig=43=config NFT_DUP_IPV6\n--\nnet/ipv6/netfilter/Kconfig-49-\nnet/ipv6/netfilter/Kconfig:50:config NFT_FIB_IPV6\nnet/ipv6/netfilter/Kconfig-51-\ttristate \"nf_tables fib / ipv6 route lookup support\"\n" }
35/2	2026/06/30 06:07	llm	patch-evaluator	0m Model: gemini-3.1-pro-preview Args: null Results: null Tokens: input: 27489 output: 358 thoughts: 498 Thoughts: My Netfilter Patch Review Okay, so we're adding `NFT_FIB_IPV4` and `NFT_FIB_IPV6`. Makes sense. Now, let's summarize the configuration items required to make sure we've got everything in order: `NF_CONNTRACK`, `NF_CONNTRACK_SIP`, `NF_CT_NETLINK`, `NF_CT_NETLINK_HELPER`, `NETFILTER_NETLINK_QUEUE`, `NF_TABLES`, `NFT_FIB_IPV4`, `NFT_FIB_IPV6`, `NFT_FIB_NETDEV`, and `IP_SET`. Let's do a quick double-check on `NF_TABLES_NETDEV` and `NF_TABLES_INET` since they can sometimes be tricky. Ah, right, `NFT_FIB_NETDEV` depends on `NFT_FIB_IPV4`, and `NFT_FIB_INET` depends on `NF_TABLES_INET`. To be absolutely sure, I'm going to include both `NF_TABLES_NETDEV` and `NF_TABLES_INET`. Better safe than sorry when dealing with these core components. Now, let's get a look at the key symbols involved. We have `ip_set_dump_do`, `ip_set_dump_done`, `ctnetlink_alloc_expect`, `set_expected_rtp_rtcp`, `nfnl_cthelper_expect_policy`, `nfqnl_mangle`, `nft_fib_validate`, `nft_fib_netdev_validate`, `nft_payload_set_init`, `nft_payload_set_eval`, and `nft_pipapo_insert`. Looks like this is a solid list covering the areas where changes were directly implemented or where the logic has been updated, right where it matters. From a functional standpoint, this patch series introduces some important, quite deep changes to Netfilter. We have new validation steps for payload writes and IP/IPv6 headers before mangling, that's crucial for security. Then there's the fix for the SIP conntrack expectation bug, a state tracking addition for pipapo set clones that should help handle aborts more robustly, and the modifications to conntrack expectation allocation and initialization. All of these affect core Netfilter logic. We're talking Netlink queue, nftables payload mangling, and pipapo sets, and that's all stuff that userspace has direct access to, so this needs to be rigorously tested. We absolutely need to make sure we're not introducing regressions or vulnerabilities here. We have to fuzz it heavily. Right, I'm going to run the `set-results` tool now to see how the change impacts the system.
36/2	2026/06/30 06:07	tool	set-results	0m Args: { "EnableConfigs": [ "NF_CONNTRACK", "NF_CONNTRACK_SIP", "NF_CT_NETLINK", "NF_CT_NETLINK_HELPER", "NETFILTER_NETLINK_QUEUE", "NF_TABLES", "NF_TABLES_INET", "NF_TABLES_NETDEV", "NFT_FIB_IPV4", "NFT_FIB_IPV6", "NFT_FIB_NETDEV", "IP_SET" ], "FocusSymbols": [ "ip_set_dump_do", "ip_set_dump_done", "ctnetlink_alloc_expect", "set_expected_rtp_rtcp", "nfnl_cthelper_expect_policy", "nfqnl_mangle", "nft_fib_validate", "nft_fib_netdev_validate", "nft_payload_set_init", "nft_payload_set_eval", "nft_pipapo_insert" ], "Reasoning": "The patch series introduces significant functional changes to the netfilter subsystem. It adds validation for payload writes and IP/IPv6 headers before mangling, fixes a bug in SIP conntrack expectation, adds state tracking for pipapo set clones to properly handle aborts, and modifies conntrack expectation allocation and initialization. These changes affect core netfilter logic, netlink queue, nftables payload mangling, and pipapo sets, which are all reachable from userspace and should be heavily fuzzed to ensure no regressions or vulnerabilities are introduced.", "WorthFuzzing": true } Results: { "EnableConfigs": [ "NF_CONNTRACK", "NF_CONNTRACK_SIP", "NF_CT_NETLINK", "NF_CT_NETLINK_HELPER", "NETFILTER_NETLINK_QUEUE", "NF_TABLES", "NF_TABLES_INET", "NF_TABLES_NETDEV", "NFT_FIB_IPV4", "NFT_FIB_IPV6", "NFT_FIB_NETDEV", "IP_SET" ], "FocusSymbols": [ "ip_set_dump_do", "ip_set_dump_done", "ctnetlink_alloc_expect", "set_expected_rtp_rtcp", "nfnl_cthelper_expect_policy", "nfqnl_mangle", "nft_fib_validate", "nft_fib_netdev_validate", "nft_payload_set_init", "nft_payload_set_eval", "nft_pipapo_insert" ], "Reasoning": "The patch series introduces significant functional changes to the netfilter subsystem. It adds validation for payload writes and IP/IPv6 headers before mangling, fixes a bug in SIP conntrack expectation, adds state tracking for pipapo set clones to properly handle aborts, and modifies conntrack expectation allocation and initialization. These changes affect core netfilter logic, netlink queue, nftables payload mangling, and pipapo sets, which are all reachable from userspace and should be heavily fuzzed to ensure no regressions or vulnerabilities are introduced.", "WorthFuzzing": true }

{
  "EnableConfigs": [
    "NF_CONNTRACK",
    "NF_CONNTRACK_SIP",
    "NF_CT_NETLINK",
    "NF_CT_NETLINK_HELPER",
    "NETFILTER_NETLINK_QUEUE",
    "NF_TABLES",
    "NF_TABLES_INET",
    "NF_TABLES_NETDEV",
    "NFT_FIB_IPV4",
    "NFT_FIB_IPV6",
    "NFT_FIB_NETDEV",
    "IP_SET"
  ],
  "FocusSymbols": [
    "ip_set_dump_do",
    "ip_set_dump_done",
    "ctnetlink_alloc_expect",
    "set_expected_rtp_rtcp",
    "nfnl_cthelper_expect_policy",
    "nfqnl_mangle",
    "nft_fib_validate",
    "nft_fib_netdev_validate",
    "nft_payload_set_init",
    "nft_payload_set_eval",
    "nft_pipapo_insert"
  ],
  "Reasoning": "The patch series introduces significant functional changes to the netfilter subsystem. It adds validation for payload writes and IP/IPv6 headers before mangling, fixes a bug in SIP conntrack expectation, adds state tracking for pipapo set clones to properly handle aborts, and modifies conntrack expectation allocation and initialization. These changes affect core netfilter logic, netlink queue, nftables payload mangling, and pipapo sets, which are all reachable from userspace and should be heavily fuzzed to ensure no regressions or vulnerabilities are introduced.",
  "WorthFuzzing": true
}

{
  "PatchDiff": "commit 58582af80852c31a696b9ada2a9b7141bbd60d8d\nAuthor: syz-cluster \u003ctriage@syzkaller.com\u003e\nDate:   Tue Jun 30 06:06:01 2026 +0000\n\n    syz-cluster: applied patch under review\n\ndiff --git a/net/netfilter/ipset/ip_set_core.c b/net/netfilter/ipset/ip_set_core.c\nindex a531b654b8d964..6cfad152d7d1ba 100644\n--- a/net/netfilter/ipset/ip_set_core.c\n+++ b/net/netfilter/ipset/ip_set_core.c\n@@ -1480,7 +1480,11 @@ ip_set_dump_done(struct netlink_callback *cb)\n \t\tstruct ip_set_net *inst =\n \t\t\t(struct ip_set_net *)cb-\u003eargs[IPSET_CB_NET];\n \t\tip_set_id_t index = (ip_set_id_t)cb-\u003eargs[IPSET_CB_INDEX];\n-\t\tstruct ip_set *set = ip_set_ref_netlink(inst, index);\n+\t\tstruct ip_set *set;\n+\n+\t\trcu_read_lock();\n+\t\tset = ip_set_ref_netlink(inst, index);\n+\t\trcu_read_unlock();\n \n \t\tif (set-\u003evariant-\u003euref)\n \t\t\tset-\u003evariant-\u003euref(set, cb, false);\n@@ -1686,7 +1690,9 @@ ip_set_dump_do(struct sk_buff *skb, struct netlink_callback *cb)\n release_refcount:\n \t/* If there was an error or set is done, release set */\n \tif (ret || !cb-\u003eargs[IPSET_CB_ARG0]) {\n+\t\trcu_read_lock();\n \t\tset = ip_set_ref_netlink(inst, index);\n+\t\trcu_read_unlock();\n \t\tif (set-\u003evariant-\u003euref)\n \t\t\tset-\u003evariant-\u003euref(set, cb, false);\n \t\tpr_debug(\"release set %s\\n\", set-\u003ename);\ndiff --git a/net/netfilter/nf_conntrack_expect.c b/net/netfilter/nf_conntrack_expect.c\nindex 38630c5e006f08..7ae68d60586a23 100644\n--- a/net/netfilter/nf_conntrack_expect.c\n+++ b/net/netfilter/nf_conntrack_expect.c\n@@ -306,7 +306,7 @@ struct nf_conntrack_expect *nf_ct_expect_alloc(struct nf_conn *me)\n {\n \tstruct nf_conntrack_expect *new;\n \n-\tnew = kmem_cache_alloc(nf_ct_expect_cachep, GFP_ATOMIC);\n+\tnew = kmem_cache_zalloc(nf_ct_expect_cachep, GFP_ATOMIC);\n \tif (!new)\n \t\treturn NULL;\n \n@@ -391,6 +391,7 @@ void nf_ct_expect_init(struct nf_conntrack_expect *exp, unsigned int class,\n #if IS_ENABLED(CONFIG_NF_NAT)\n \tmemset(\u0026exp-\u003esaved_addr, 0, sizeof(exp-\u003esaved_addr));\n \tmemset(\u0026exp-\u003esaved_proto, 0, sizeof(exp-\u003esaved_proto));\n+\texp-\u003edir = 0;\n #endif\n }\n EXPORT_SYMBOL_GPL(nf_ct_expect_init);\ndiff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c\nindex 4217715d42dc24..31cbb1b55b9e6c 100644\n--- a/net/netfilter/nf_conntrack_netlink.c\n+++ b/net/netfilter/nf_conntrack_netlink.c\n@@ -3549,8 +3549,6 @@ ctnetlink_alloc_expect(const struct nlattr * const cda[], struct nf_conn *ct,\n \tif (cda[CTA_EXPECT_FLAGS]) {\n \t\texp-\u003eflags = ntohl(nla_get_be32(cda[CTA_EXPECT_FLAGS]));\n \t\texp-\u003eflags \u0026= ~NF_CT_EXPECT_USERSPACE;\n-\t} else {\n-\t\texp-\u003eflags = 0;\n \t}\n \tif (cda[CTA_EXPECT_FN]) {\n \t\tconst char *name = nla_data(cda[CTA_EXPECT_FN]);\n@@ -3562,8 +3560,7 @@ ctnetlink_alloc_expect(const struct nlattr * const cda[], struct nf_conn *ct,\n \t\t\tgoto err_out;\n \t\t}\n \t\texp-\u003eexpectfn = expfn-\u003eexpectfn;\n-\t} else\n-\t\texp-\u003eexpectfn = NULL;\n+\t}\n \n \texp-\u003eclass = class;\n \texp-\u003emaster = ct;\n@@ -3583,12 +3580,6 @@ ctnetlink_alloc_expect(const struct nlattr * const cda[], struct nf_conn *ct,\n \t\t\t\t\t\t exp, nf_ct_l3num(ct));\n \t\tif (err \u003c 0)\n \t\t\tgoto err_out;\n-#if IS_ENABLED(CONFIG_NF_NAT)\n-\t} else {\n-\t\tmemset(\u0026exp-\u003esaved_addr, 0, sizeof(exp-\u003esaved_addr));\n-\t\tmemset(\u0026exp-\u003esaved_proto, 0, sizeof(exp-\u003esaved_proto));\n-\t\texp-\u003edir = 0;\n-#endif\n \t}\n \treturn exp;\n err_out:\ndiff --git a/net/netfilter/nf_conntrack_sip.c b/net/netfilter/nf_conntrack_sip.c\nindex 5ec3a4a4bbd707..f3f90a86633894 100644\n--- a/net/netfilter/nf_conntrack_sip.c\n+++ b/net/netfilter/nf_conntrack_sip.c\n@@ -956,7 +956,6 @@ static int set_expected_rtp_rtcp(struct sk_buff *skb, unsigned int protoff,\n \t\t\treturn NF_ACCEPT;\n \t\tsaddr = \u0026ct-\u003etuplehash[!dir].tuple.src.u3;\n \t} else if (sip_external_media) {\n-\t\tstruct net_device *dev = skb_dst(skb)-\u003edev;\n \t\tstruct dst_entry *dst = NULL;\n \t\tstruct flowi fl;\n \n@@ -978,7 +977,11 @@ static int set_expected_rtp_rtcp(struct sk_buff *skb, unsigned int protoff,\n \t\t * through the same interface as the signalling peer.\n \t\t */\n \t\tif (dst) {\n-\t\t\tbool external_media = (dst-\u003edev == dev);\n+\t\t\tconst struct dst_entry *this_dst = skb_dst(skb);\n+\t\t\tbool external_media = false;\n+\n+\t\t\tif (this_dst \u0026\u0026 dst-\u003edev == this_dst-\u003edev)\n+\t\t\t\texternal_media = true;\n \n \t\t\tdst_release(dst);\n \t\t\tif (external_media)\ndiff --git a/net/netfilter/nfnetlink_cthelper.c b/net/netfilter/nfnetlink_cthelper.c\nindex f1460b683d7af7..2cbcca9110dbf5 100644\n--- a/net/netfilter/nfnetlink_cthelper.c\n+++ b/net/netfilter/nfnetlink_cthelper.c\n@@ -163,6 +163,8 @@ nfnl_cthelper_expect_policy(struct nf_conntrack_expect_policy *expect_policy,\n \t\t    tb[NFCTH_POLICY_NAME], NF_CT_HELPER_NAME_LEN);\n \texpect_policy-\u003emax_expected =\n \t\tntohl(nla_get_be32(tb[NFCTH_POLICY_EXPECT_MAX]));\n+\tif (!expect_policy-\u003emax_expected)\n+\t\texpect_policy-\u003emax_expected = NF_CT_EXPECT_MAX_CNT;\n \tif (expect_policy-\u003emax_expected \u003e NF_CT_EXPECT_MAX_CNT)\n \t\treturn -EINVAL;\n \ndiff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c\nindex 80ca077b81bd5a..35d4c6c628ffc1 100644\n--- a/net/netfilter/nfnetlink_queue.c\n+++ b/net/netfilter/nfnetlink_queue.c\n@@ -1184,6 +1184,173 @@ nfqnl_enqueue_packet(struct nf_queue_entry *entry, unsigned int queuenum)\n \treturn err;\n }\n \n+static bool nfqnl_validate_ipopts(const struct iphdr *iph_new,\n+\t\t\t\t  const struct nf_queue_entry *e)\n+{\n+\tconst struct iphdr *iph_orig = ip_hdr(e-\u003eskb);\n+\tunsigned int ihl = iph_new-\u003eihl * 4;\n+\n+\tif (iph_new-\u003eihl != iph_orig-\u003eihl)\n+\t\treturn false;\n+\tif (ihl == sizeof(*iph_orig))\n+\t\treturn true;\n+\n+\treturn memcmp(iph_new + 1, ip_hdr(e-\u003eskb) + 1, ihl - sizeof(*iph_orig)) == 0;\n+}\n+\n+static bool nfqnl_validate_ip4(const struct iphdr *iph, unsigned int data_len,\n+\t\t\t       const struct nf_queue_entry *e)\n+{\n+\tunsigned int ihl;\n+\n+\tif (data_len \u003c sizeof(*iph))\n+\t\treturn false;\n+\n+\tihl = iph-\u003eihl * 4u;\n+\tif (ihl \u003c sizeof(*iph) || data_len \u003c ihl)\n+\t\treturn false;\n+\n+\tif (iph-\u003eversion != 4 ||\n+\t    ((iph-\u003efrag_off ^ ip_hdr(e-\u003eskb)-\u003efrag_off) \u0026 ~htons(IP_DF)) != 0)\n+\t\treturn false;\n+\n+\t/* BIG TCP won't work; netlink attr len is u16 */\n+\tif (ntohs(iph-\u003etot_len) != data_len)\n+\t\treturn false;\n+\n+\t/* support for ipopts mangling would require\n+\t * recompile + skb transport header update.\n+\t */\n+\treturn nfqnl_validate_ipopts(iph, e);\n+}\n+\n+static bool nfqnl_validate_one_exthdr(const u8 *data,\n+\t\t\t\t      unsigned int data_len,\n+\t\t\t\t      const struct nf_queue_entry *e,\n+\t\t\t\t      int start, int hdrlen)\n+{\n+\tu16 octets;\n+\n+\tif (data_len \u003c hdrlen || hdrlen \u003c 2)\n+\t\treturn false;\n+\n+\twhile (hdrlen \u003e 0) {\n+\t\tif (data_len \u003c sizeof(octets))\n+\t\t\treturn false;\n+\t\tdata_len -= sizeof(octets);\n+\n+\t\tif (skb_copy_bits(e-\u003eskb, start, \u0026octets, sizeof(octets)))\n+\t\t\treturn false;\n+\n+\t\tif (hdrlen \u003c sizeof(octets))\n+\t\t\treturn false;\n+\n+\t\thdrlen -= sizeof(octets);\n+\t\tif (memcmp(data, \u0026octets, sizeof(octets)))\n+\t\t\treturn false;\n+\n+\t\tstart += sizeof(octets);\n+\t\tdata += sizeof(octets);\n+\t}\n+\n+\treturn true;\n+}\n+\n+static bool nfqnl_validate_exthdr(const struct ipv6hdr *ip6_new,\n+\t\t\t\t  unsigned int data_len,\n+\t\t\t\t  const struct nf_queue_entry *e)\n+{\n+\tconst struct ipv6hdr *ip6_orig = ipv6_hdr(e-\u003eskb);\n+\tint exthdr_cnt = 0, start = sizeof(*ip6_orig);\n+\tconst u8 *data = (const u8 *)ip6_new;\n+\tu8 orig_nexthdr = ip6_orig-\u003enexthdr;\n+\tu8 new_nexthdr = ip6_new-\u003enexthdr;\n+\n+\tif (new_nexthdr != orig_nexthdr)\n+\t\treturn false;\n+\n+\tdata += sizeof(*ip6_new);\n+\tdata_len -= sizeof(*ip6_new);\n+\n+\twhile (ipv6_ext_hdr(orig_nexthdr)) {\n+\t\tconst struct ipv6_opt_hdr *hp;\n+\t\tstruct ipv6_opt_hdr _hdr;\n+\t\tint hdrlen;\n+\n+\t\tif (orig_nexthdr == NEXTHDR_NONE)\n+\t\t\treturn true;\n+\n+\t\tif (unlikely(exthdr_cnt++ \u003e= IP6_MAX_EXT_HDRS_CNT))\n+\t\t\treturn false;\n+\n+\t\thp = skb_header_pointer(e-\u003eskb, start, sizeof(_hdr), \u0026_hdr);\n+\t\tif (!hp)\n+\t\t\treturn false;\n+\n+\t\tswitch (orig_nexthdr) {\n+\t\tcase NEXTHDR_FRAGMENT:\n+\t\t\thdrlen = sizeof(struct frag_hdr);\n+\t\t\tbreak;\n+\t\tcase NEXTHDR_AUTH:\n+\t\t\thdrlen = ipv6_authlen(hp);\n+\t\t\tbreak;\n+\t\tdefault:\n+\t\t\thdrlen = ipv6_optlen(hp);\n+\t\t\tbreak;\n+\t\t}\n+\n+\t\tif (!nfqnl_validate_one_exthdr(data, data_len, e,\n+\t\t\t\t\t       start, hdrlen))\n+\t\t\treturn false;\n+\n+\t\torig_nexthdr = hp-\u003enexthdr;\n+\t\thp = (const void *)data;\n+\t\tnew_nexthdr = hp-\u003enexthdr;\n+\n+\t\tif (new_nexthdr != orig_nexthdr)\n+\t\t\treturn false;\n+\n+\t\tdata_len -= hdrlen;\n+\t\tstart += hdrlen;\n+\t\tdata += hdrlen;\n+\t}\n+\n+\treturn true;\n+}\n+\n+static bool nfqnl_validate_ip6(const struct ipv6hdr *ip6, unsigned int data_len,\n+\t\t\t       const struct nf_queue_entry *e)\n+{\n+\tif (data_len \u003c sizeof(*ip6))\n+\t\treturn false;\n+\n+\t/* BIG TCP/jumbograms won't work; netlink attr len is u16 */\n+\tif (ntohs(ip6-\u003epayload_len) != data_len - sizeof(*ip6))\n+\t\treturn false;\n+\n+\tif (ip6-\u003eversion != 6)\n+\t\treturn false;\n+\n+\treturn nfqnl_validate_exthdr(ip6, data_len, e);\n+}\n+\n+static bool nfqnl_validate_write(const void *data, unsigned int data_len,\n+\t\t\t\t const struct nf_queue_entry *e)\n+{\n+\tswitch (e-\u003estate.pf) {\n+\tcase NFPROTO_IPV4:\n+\t\treturn nfqnl_validate_ip4(data, data_len, e);\n+\tcase NFPROTO_IPV6:\n+\t\treturn nfqnl_validate_ip6(data, data_len, e) \u0026\u0026\n+\t\t       !(IP6CB(e-\u003eskb)-\u003eflags \u0026 IP6SKB_JUMBOGRAM);\n+\tcase NFPROTO_BRIDGE:\n+\t\t/* No write support. Bridge is dubious: userspace doesn't even see L2 header */\n+\t\treturn false;\n+\t}\n+\n+\treturn false;\n+}\n+\n static int\n nfqnl_mangle(void *data, unsigned int data_len, struct nf_queue_entry *e, int diff)\n {\n@@ -1192,6 +1359,9 @@ nfqnl_mangle(void *data, unsigned int data_len, struct nf_queue_entry *e, int di\n \tif (e-\u003estate.net-\u003euser_ns != \u0026init_user_ns)\n \t\treturn -EPERM;\n \n+\tif (!nfqnl_validate_write(data, data_len, e))\n+\t\treturn -EINVAL;\n+\n \tif (diff \u003c 0) {\n \t\tunsigned int min_len = skb_transport_offset(e-\u003eskb);\n \ndiff --git a/net/netfilter/nft_fib.c b/net/netfilter/nft_fib.c\nindex e048f05694cddd..89555380f1c5a0 100644\n--- a/net/netfilter/nft_fib.c\n+++ b/net/netfilter/nft_fib.c\n@@ -31,6 +31,15 @@ int nft_fib_validate(const struct nft_ctx *ctx, const struct nft_expr *expr)\n \tconst struct nft_fib *priv = nft_expr_priv(expr);\n \tunsigned int hooks;\n \n+\tswitch (ctx-\u003efamily) {\n+\tcase NFPROTO_IPV4:\n+\tcase NFPROTO_IPV6:\n+\tcase NFPROTO_INET:\n+\t\tbreak;\n+\tdefault:\n+\t\treturn -EOPNOTSUPP;\n+\t}\n+\n \tswitch (priv-\u003eresult) {\n \tcase NFT_FIB_RESULT_OIF:\n \tcase NFT_FIB_RESULT_OIFNAME:\ndiff --git a/net/netfilter/nft_fib_netdev.c b/net/netfilter/nft_fib_netdev.c\nindex 3f3478abd84546..5774a754402780 100644\n--- a/net/netfilter/nft_fib_netdev.c\n+++ b/net/netfilter/nft_fib_netdev.c\n@@ -50,6 +50,33 @@ static void nft_fib_netdev_eval(const struct nft_expr *expr,\n \tregs-\u003everdict.code = NFT_BREAK;\n }\n \n+static int nft_fib_netdev_validate(const struct nft_ctx *ctx,\n+\t\t\t\t   const struct nft_expr *expr)\n+{\n+\tconst struct nft_fib *priv = nft_expr_priv(expr);\n+\tunsigned int hooks;\n+\n+\tswitch (priv-\u003eresult) {\n+\tcase NFT_FIB_RESULT_OIF:\n+\tcase NFT_FIB_RESULT_OIFNAME:\n+\t\thooks = (1 \u003c\u003c NF_NETDEV_INGRESS);\n+\t\tbreak;\n+\tcase NFT_FIB_RESULT_ADDRTYPE:\n+\t\tif (priv-\u003eflags \u0026 NFTA_FIB_F_IIF)\n+\t\t\thooks = (1 \u003c\u003c NF_NETDEV_INGRESS);\n+\t\telse if (priv-\u003eflags \u0026 NFTA_FIB_F_OIF)\n+\t\t\thooks = (1 \u003c\u003c NF_NETDEV_EGRESS);\n+\t\telse\n+\t\t\thooks = (1 \u003c\u003c NF_NETDEV_INGRESS) |\n+\t\t\t\t(1 \u003c\u003c NF_NETDEV_EGRESS);\n+\t\tbreak;\n+\tdefault:\n+\t\treturn -EINVAL;\n+\t}\n+\n+\treturn nft_chain_validate_hooks(ctx-\u003echain, hooks);\n+}\n+\n static struct nft_expr_type nft_fib_netdev_type;\n static const struct nft_expr_ops nft_fib_netdev_ops = {\n \t.type\t\t= \u0026nft_fib_netdev_type,\n@@ -57,7 +84,7 @@ static const struct nft_expr_ops nft_fib_netdev_ops = {\n \t.eval\t\t= nft_fib_netdev_eval,\n \t.init\t\t= nft_fib_init,\n \t.dump\t\t= nft_fib_dump,\n-\t.validate\t= nft_fib_validate,\n+\t.validate\t= nft_fib_netdev_validate,\n };\n \n static struct nft_expr_type nft_fib_netdev_type __read_mostly = {\ndiff --git a/net/netfilter/nft_payload.c b/net/netfilter/nft_payload.c\nindex 345eff140d56f8..391539a1ceaa77 100644\n--- a/net/netfilter/nft_payload.c\n+++ b/net/netfilter/nft_payload.c\n@@ -834,6 +834,249 @@ nft_payload_set_vlan(const u32 *src, struct sk_buff *skb, u16 offset, u8 len,\n \treturn true;\n }\n \n+/* Ingress is very early, before l3 protocol handlers.\n+ * There should be no in-tree code that trusts l3/l4 headers\n+ * between ingress and NF_INET_PRE_ROUTING hooks.\n+ */\n+static bool nft_in_ingress(const struct nf_hook_state *s)\n+{\n+\treturn s-\u003epf == NFPROTO_NETDEV \u0026\u0026 s-\u003ehook == NF_NETDEV_INGRESS;\n+}\n+\n+static bool nft_nh_write_ok_ip4(const struct nft_pktinfo *pkt,\n+\t\t\t\tconst struct nft_payload_set *priv,\n+\t\t\t\tconst u32 *src)\n+{\n+\tunsigned int offset = priv-\u003eoffset + skb_network_offset(pkt-\u003eskb);\n+\tconst u8 *new_octets = (const u8 *)src;\n+\tu8 old_octet;\n+\n+\tswitch (priv-\u003eoffset) {\n+\tcase 0: /* csum fixups does expand dscp/tos store to 2 bytes.\n+\t\t * make sure ihl/version remain unchanged.\n+\t\t */\n+\t\tif (skb_copy_bits(pkt-\u003eskb, offset, \u0026old_octet, sizeof(old_octet)))\n+\t\t\treturn false;\n+\n+\t\treturn priv-\u003elen == 2 \u0026\u0026\n+\t\t       *new_octets == old_octet;\n+\tcase offsetof(struct iphdr, tos):\n+\t\treturn priv-\u003elen == 1;\n+\tcase offsetof(struct iphdr, id):\n+\t\treturn priv-\u003elen == 2;\n+\tcase offsetof(struct iphdr, ttl):\n+\t\tif (priv-\u003elen == 1)\n+\t\t\treturn true;\n+\n+\t\tif (priv-\u003elen != 2)\n+\t\t\treturn false;\n+\n+\t\t/* same, csum fixup does expand ttl store to two bytes.\n+\t\t * check protocol is not altered.\n+\t\t */\n+\t\tif (skb_copy_bits(pkt-\u003eskb, offset + 1, \u0026old_octet, sizeof(old_octet)))\n+\t\t\treturn false;\n+\n+\t\treturn new_octets[1] == old_octet;\n+\tcase offsetof(struct iphdr, check):\n+\t\treturn priv-\u003elen \u003c= 2 + 4 + 4;\n+\tcase offsetof(struct iphdr, saddr):\n+\t\treturn priv-\u003elen \u003c= 4 + 4;\n+\tcase offsetof(struct iphdr, daddr):\n+\t\treturn priv-\u003elen \u003c= 4;\n+\t}\n+\n+\treturn false;\n+}\n+\n+static bool nft_nh_write_ok_ip6(const struct nft_pktinfo *pkt,\n+\t\t\t\tconst struct nft_payload_set *priv,\n+\t\t\t\tconst u32 *src)\n+{\n+\tconst struct ipv6hdr *ih = (const void *)src;\n+\n+\tswitch (priv-\u003eoffset) {\n+\tcase 0: /* store to dscp must not alter ip6 version */\n+\t\treturn priv-\u003elen \u003c= 4 \u0026\u0026 ih-\u003eversion == 6;\n+\tcase 2:\n+\t\treturn priv-\u003elen \u003c= 2;\n+\tcase offsetof(struct ipv6hdr, hop_limit):\n+\t\treturn priv-\u003elen == 1;\n+\tcase offsetof(struct ipv6hdr, saddr):\n+\t\treturn priv-\u003elen \u003c= 16 + 16;\n+\tcase offsetof(struct ipv6hdr, daddr):\n+\t\treturn priv-\u003elen \u003c= 16;\n+\t}\n+\n+\treturn false;\n+}\n+\n+static bool nft_nh_write_ok_arp(const struct nft_payload_set *priv)\n+{\n+\t/* Variable size for standard ethernet arp */\n+\tconst unsigned int eth_ip = 2 * (ETH_ALEN + 4);\n+\tunsigned int offset = priv-\u003eoffset;\n+\n+\tswitch (offset) {\n+\tcase offsetof(struct arphdr, ar_op):\n+\t\treturn priv-\u003elen == 2;\n+\tdefault:\n+\t\tbreak;\n+\t}\n+\n+\t/* permit writes post fixed arp header size. offset + len are\n+\t * checked vs skb size via skb_ensure_writable.\n+\t */\n+\treturn offset \u003e= sizeof(struct arphdr) \u0026\u0026 priv-\u003elen \u003c= eth_ip;\n+}\n+\n+static bool nft_nh_write_ok_netdev(const struct nft_pktinfo *pkt,\n+\t\t\t\t   const struct nft_payload_set *priv,\n+\t\t\t\t   const u32 *src)\n+{\n+#ifdef CONFIG_NF_TABLES_NETDEV\n+\tswitch (pkt-\u003eskb-\u003eprotocol) {\n+\tcase htons(ETH_P_ARP):\n+\t\treturn nft_nh_write_ok_arp(priv);\n+\tcase htons(ETH_P_IP):\n+\t\treturn nft_nh_write_ok_ip4(pkt, priv, src);\n+\tcase htons(ETH_P_IPV6):\n+\t\treturn nft_nh_write_ok_ip6(pkt, priv, src);\n+\t}\n+#endif\n+\t/* default to false for now, relax later in case we have\n+\t * use-cases that need inner header manipulation for\n+\t * encapsulated traffic like vlan or PPPoE.\n+\t */\n+\treturn false;\n+}\n+\n+static bool nft_nh_write_ok_bridge(const struct nft_pktinfo *pkt,\n+\t\t\t\t   const struct nft_payload_set *priv,\n+\t\t\t\t   const u32 *src)\n+{\n+#if IS_ENABLED(CONFIG_NF_TABLES_BRIDGE)\n+\tswitch (pkt-\u003eethertype) {\n+\tcase htons(ETH_P_ARP):\n+\t\treturn nft_nh_write_ok_arp(priv);\n+\tcase htons(ETH_P_IP):\n+\t\treturn nft_nh_write_ok_ip4(pkt, priv, src);\n+\tcase htons(ETH_P_IPV6):\n+\t\treturn nft_nh_write_ok_ip6(pkt, priv, src);\n+\t}\n+#endif\n+\t/* see nft_nh_write_ok_netdev: default to false */\n+\treturn false;\n+}\n+\n+static bool nft_nh_write_ok(const struct nft_pktinfo *pkt,\n+\t\t\t    const struct nft_payload_set *priv,\n+\t\t\t    const u32 *src)\n+{\n+\tswitch (pkt-\u003estate-\u003epf) {\n+\tcase NFPROTO_ARP:\n+\t\treturn nft_nh_write_ok_arp(priv);\n+\tcase NFPROTO_BRIDGE:\n+\t\treturn nft_nh_write_ok_bridge(pkt, priv, src);\n+\tcase NFPROTO_IPV4:\n+\t\treturn nft_nh_write_ok_ip4(pkt, priv, src);\n+\tcase NFPROTO_IPV6:\n+\t\treturn nft_nh_write_ok_ip6(pkt, priv, src);\n+\tcase NFPROTO_NETDEV:\n+\t\tif (pkt-\u003estate-\u003ehook == NF_NETDEV_INGRESS)\n+\t\t\treturn true;\n+\t\treturn nft_nh_write_ok_netdev(pkt, priv, src);\n+\t}\n+\n+\treturn false;\n+}\n+\n+/* check linklayer modifications don't spill into network header. */\n+static bool nft_ll_write_ok(const struct nft_pktinfo *pkt, int offset)\n+{\n+\tif (nft_in_ingress(pkt-\u003estate))\n+\t\treturn true;\n+\n+\treturn offset \u003c= skb_network_offset(pkt-\u003eskb);\n+}\n+\n+static bool nft_payload_validate_inet_csum_offset(const struct nft_ctx *ctx,\n+\t\t\t\t\t\t  const struct nft_payload_set *priv)\n+{\n+\tswitch (priv-\u003ebase) {\n+\tcase NFT_PAYLOAD_LL_HEADER:\n+\t\tbreak;\n+\tcase NFT_PAYLOAD_NETWORK_HEADER:\n+\t\tif (ctx-\u003efamily == NFPROTO_IPV4) {\n+\t\t\tif (offsetof(struct iphdr, check) == priv-\u003ecsum_offset)\n+\t\t\t\treturn true;\n+\n+\t\t\treturn false;\n+\t\t}\n+\t\treturn true; /* run time validation required */\n+\tcase NFT_PAYLOAD_TRANSPORT_HEADER:\n+\t\tif (priv-\u003ecsum_flags) /* makes no sense, asks for \"re-update\" of L4 checksum */\n+\t\t\treturn false;\n+\n+\t\t/* no further check here; offset can't be negative so bogus\n+\t\t * offsets can corrupt L4 or payload but not l3 headers.\n+\t\t * We already allow arbitrary l4/inner payload writes.\n+\t\t */\n+\t\treturn true;\n+\tcase NFT_PAYLOAD_INNER_HEADER:\n+\t\treturn true;\n+\tcase NFT_PAYLOAD_TUN_HEADER:\n+\t\tbreak;\n+\t}\n+\n+\treturn false;\n+}\n+\n+/* do not allow arbitrary network header mangling via bogus csum_off.\n+ * We only support ipv4.  Only NFPROTO_IPV4 can be checked from control\n+ * plane.\n+ */\n+static bool nft_payload_csum_nh_write_ok(const struct nft_payload_set *priv,\n+\t\t\t\t\t const struct nft_pktinfo *pkt)\n+{\n+\tswitch (pkt-\u003estate-\u003epf) {\n+\tcase NFPROTO_IPV4:\n+\t\t/* Warning: NFPROTO_INET was not checked; we can't return true here. */\n+\t\treturn priv-\u003ecsum_offset == offsetof(struct iphdr, check);\n+\tcase NFPROTO_IPV6:\n+\t\treturn false;\n+\tcase NFPROTO_BRIDGE:\n+\t\treturn pkt-\u003eethertype == htons(ETH_P_IP) \u0026\u0026\n+\t\t       priv-\u003ecsum_offset == offsetof(struct iphdr, check);\n+\tcase NFPROTO_NETDEV:\n+\t\treturn pkt-\u003eskb-\u003eprotocol == htons(ETH_P_IP) \u0026\u0026\n+\t\t       priv-\u003ecsum_offset == offsetof(struct iphdr, check);\n+\t}\n+\n+\treturn false;\n+}\n+\n+static bool nft_payload_csum_write_ok(const struct nft_pktinfo *pkt,\n+\t\t\t\t      const struct nft_payload_set *priv)\n+{\n+\tswitch (priv-\u003ebase) {\n+\tcase NFT_PAYLOAD_LL_HEADER:\n+\t\tbreak;\n+\tcase NFT_PAYLOAD_NETWORK_HEADER:\n+\t\treturn nft_payload_csum_nh_write_ok(priv, pkt);\n+\tcase NFT_PAYLOAD_TRANSPORT_HEADER:\n+\tcase NFT_PAYLOAD_INNER_HEADER:\n+\t\t/* neither offsets are validated, offsets cannot be\n+\t\t * negative so real l3 headers cannot be mangled.\n+\t\t */\n+\t\treturn true;\n+\tcase NFT_PAYLOAD_TUN_HEADER:\n+\t\tbreak;\n+\t}\n+\n+\treturn false;\n+}\n+\n static void nft_payload_set_eval(const struct nft_expr *expr,\n \t\t\t\t struct nft_regs *regs,\n \t\t\t\t const struct nft_pktinfo *pkt)\n@@ -861,8 +1104,12 @@ static void nft_payload_set_eval(const struct nft_expr *expr,\n \t\t}\n \n \t\toffset = skb_mac_header(skb) - skb-\u003edata - vlan_hlen;\n+\t\tif (!nft_ll_write_ok(pkt, priv-\u003elen + priv-\u003eoffset + offset))\n+\t\t\tgoto err;\n \t\tbreak;\n \tcase NFT_PAYLOAD_NETWORK_HEADER:\n+\t\tif (!nft_nh_write_ok(pkt, priv, src))\n+\t\t\tgoto err;\n \t\toffset = skb_network_offset(skb);\n \t\tbreak;\n \tcase NFT_PAYLOAD_TRANSPORT_HEADER:\n@@ -894,6 +1141,7 @@ static void nft_payload_set_eval(const struct nft_expr *expr,\n \t\ttsum = csum_partial(src, priv-\u003elen, 0);\n \n \t\tif (priv-\u003ecsum_type == NFT_PAYLOAD_CSUM_INET \u0026\u0026\n+\t\t    nft_payload_csum_write_ok(pkt, priv) \u0026\u0026\n \t\t    nft_payload_csum_inet(skb, src, fsum, tsum, csum_offset))\n \t\t\tgoto err;\n \n@@ -960,7 +1208,26 @@ static int nft_payload_set_init(const struct nft_ctx *ctx,\n \n \tswitch (csum_type) {\n \tcase NFT_PAYLOAD_CSUM_NONE:\n+\t\tif (priv-\u003ecsum_offset) /* nonsensical */\n+\t\t\treturn -EINVAL;\n+\n+\t\tif (priv-\u003ecsum_flags == 0)\n+\t\t\tbreak;\n+\n+\t\t/* Userspace requests L4 checksum update, e.g.:\n+\t\t * - IPv6 stateless NAT (no l3 csum)\n+\t\t * - transport header mangling\n+\t\t * - inner data mangling\n+\t\t */\n+\t\tif (priv-\u003ebase == NFT_PAYLOAD_NETWORK_HEADER ||\n+\t\t    priv-\u003ebase == NFT_PAYLOAD_TRANSPORT_HEADER ||\n+\t\t    priv-\u003ebase == NFT_PAYLOAD_INNER_HEADER)\n+\t\t\tbreak;\n+\n+\t\treturn -EINVAL;\n \tcase NFT_PAYLOAD_CSUM_INET:\n+\t\tif (!nft_payload_validate_inet_csum_offset(ctx, priv))\n+\t\t\treturn -EINVAL;\n \t\tbreak;\n \tcase NFT_PAYLOAD_CSUM_SCTP:\n \t\tif (priv-\u003ebase != NFT_PAYLOAD_TRANSPORT_HEADER)\n@@ -968,6 +1235,9 @@ static int nft_payload_set_init(const struct nft_ctx *ctx,\n \n \t\tif (priv-\u003ecsum_offset != offsetof(struct sctphdr, checksum))\n \t\t\treturn -EINVAL;\n+\n+\t\tif (priv-\u003ecsum_flags)\n+\t\t\treturn -EINVAL;\n \t\tbreak;\n \tdefault:\n \t\treturn -EOPNOTSUPP;\ndiff --git a/net/netfilter/nft_set_pipapo.c b/net/netfilter/nft_set_pipapo.c\nindex 706c78853f245b..978bb0c0110682 100644\n--- a/net/netfilter/nft_set_pipapo.c\n+++ b/net/netfilter/nft_set_pipapo.c\n@@ -342,6 +342,8 @@\n #include \"nft_set_pipapo_avx2.h\"\n #include \"nft_set_pipapo.h\"\n \n+static void nft_pipapo_abort(const struct nft_set *set);\n+\n /**\n  * pipapo_refill() - For each set bit, set bits from selected mapping table item\n  * @map:\tBitmap to be scanned for set bits\n@@ -1296,7 +1298,7 @@ static int nft_pipapo_insert(const struct net *net, const struct nft_set *set,\n \tconst u8 *start_p, *end_p;\n \tint i, bsize_max, err = 0;\n \n-\tif (!m)\n+\tif (!m || m-\u003estate == NFT_PIPAPO_CLONE_ERR)\n \t\treturn -ENOMEM;\n \n \tif (nft_set_ext_exists(ext, NFT_SET_EXT_KEY_END))\n@@ -1367,8 +1369,10 @@ static int nft_pipapo_insert(const struct net *net, const struct nft_set *set,\n \t\telse\n \t\t\tret = pipapo_expand(f, start, end, f-\u003egroups * f-\u003ebb);\n \n-\t\tif (ret \u003c 0)\n-\t\t\treturn ret;\n+\t\tif (ret \u003c 0) {\n+\t\t\terr = ret;\n+\t\t\tgoto abort;\n+\t\t}\n \n \t\tif (f-\u003ebsize \u003e bsize_max)\n \t\t\tbsize_max = f-\u003ebsize;\n@@ -1384,7 +1388,7 @@ static int nft_pipapo_insert(const struct net *net, const struct nft_set *set,\n \n \t\terr = pipapo_realloc_scratch(m, bsize_max);\n \t\tif (err)\n-\t\t\treturn err;\n+\t\t\tgoto abort;\n \n \t\tm-\u003ebsize_max = bsize_max;\n \t} else {\n@@ -1396,7 +1400,26 @@ static int nft_pipapo_insert(const struct net *net, const struct nft_set *set,\n \n \tpipapo_map(m, rulemap, e);\n \n+\tm-\u003estate = NFT_PIPAPO_CLONE_MOD;\n \treturn 0;\n+abort:\n+\tDEBUG_NET_WARN_ON_ONCE(m-\u003estate == NFT_PIPAPO_CLONE_ERR);\n+\n+\t/* Two rollback cases:\n+\t * 1) no previous changes.  nft_pipapo_abort is not\n+\t * guaranteed to be invoked (there might be no further\n+\t * add/delete requests coming after this).\n+\t *\n+\t * 2) we had previous changes: there are transaction\n+\t * records pointing to this set.  Leave the rollback to\n+\t * the transaction handling.\n+\t */\n+\tif (m-\u003estate == NFT_PIPAPO_CLONE_NEW)\n+\t\tnft_pipapo_abort(set); /* releases m */\n+\telse\n+\t\tm-\u003estate = NFT_PIPAPO_CLONE_ERR;\n+\n+\treturn err;\n }\n \n /**\n@@ -1473,6 +1496,7 @@ static struct nft_pipapo_match *pipapo_clone(struct nft_pipapo_match *old)\n \t\tdst++;\n \t}\n \n+\tnew-\u003estate = NFT_PIPAPO_CLONE_NEW;\n \treturn new;\n \n out_mt:\n@@ -1896,7 +1920,7 @@ nft_pipapo_deactivate(const struct net *net, const struct nft_set *set,\n \t/* removal must occur on priv-\u003eclone, if we are low on memory\n \t * we have no choice and must fail the removal request.\n \t */\n-\tif (!m)\n+\tif (!m || m-\u003estate == NFT_PIPAPO_CLONE_ERR)\n \t\treturn NULL;\n \n \te = pipapo_get(m, (const u8 *)elem-\u003ekey.val.data,\ndiff --git a/net/netfilter/nft_set_pipapo.h b/net/netfilter/nft_set_pipapo.h\nindex b82abb03576edd..a19e980d06ef42 100644\n--- a/net/netfilter/nft_set_pipapo.h\n+++ b/net/netfilter/nft_set_pipapo.h\n@@ -131,9 +131,16 @@ struct nft_pipapo_scratch {\n \tunsigned long __map[];\n };\n \n+enum nft_pipapo_clone_state {\n+\tNFT_PIPAPO_CLONE_NEW,\n+\tNFT_PIPAPO_CLONE_MOD,\n+\tNFT_PIPAPO_CLONE_ERR,\n+};\n+\n /**\n  * struct nft_pipapo_match - Data used for lookup and matching\n  * @field_count:\tAmount of fields in set\n+ * @state:\t\tadd/delete state; used from control plane\n  * @bsize_max:\t\tMaximum lookup table bucket size of all fields, in longs\n  * @scratch:\t\tPreallocated per-CPU maps for partial matching results\n  * @rcu:\t\tMatching data is swapped on commits\n@@ -141,6 +148,7 @@ struct nft_pipapo_scratch {\n  */\n struct nft_pipapo_match {\n \tu8 field_count;\n+\tenum nft_pipapo_clone_state state:8;\n \tunsigned int bsize_max;\n \tstruct nft_pipapo_scratch * __percpu *scratch;\n \tstruct rcu_head rcu;\n"
}

gemini-3.1-pro-preview

{
  "EnableConfigs": [
    "NF_CONNTRACK",
    "NF_CONNTRACK_SIP",
    "NF_CT_NETLINK",
    "NF_CT_NETLINK_HELPER",
    "NETFILTER_NETLINK_QUEUE",
    "NF_TABLES",
    "NF_TABLES_INET",
    "NF_TABLES_NETDEV",
    "NFT_FIB_IPV4",
    "NFT_FIB_IPV6",
    "NFT_FIB_NETDEV",
    "IP_SET"
  ],
  "FocusSymbols": [
    "ip_set_dump_do",
    "ip_set_dump_done",
    "ctnetlink_alloc_expect",
    "set_expected_rtp_rtcp",
    "nfnl_cthelper_expect_policy",
    "nfqnl_mangle",
    "nft_fib_validate",
    "nft_fib_netdev_validate",
    "nft_payload_set_init",
    "nft_payload_set_eval",
    "nft_pipapo_insert"
  ],
  "Reasoning": "The patch series introduces significant functional changes to the netfilter subsystem. It adds validation for payload writes and IP/IPv6 headers before mangling, fixes a bug in SIP conntrack expectation, adds state tracking for pipapo set clones to properly handle aborts, and modifies conntrack expectation allocation and initialization. These changes affect core netfilter logic, netlink queue, nftables payload mangling, and pipapo sets, which are all reachable from userspace and should be heavily fuzzed to ensure no regressions or vulnerabilities are introduced.",
  "WorthFuzzing": true
}

You are an expert Linux kernel maintainer.
Your job is to review a provided patch series and determine
if it makes functional changes to the kernel that should be fuzzed.

IMPORTANT: The changes have ALREADY been applied and committed as the HEAD commit in
your workspace. Do NOT rely on your internal knowledge of the kernel. You must actively
use your code access tools to examine the actual source code and confirm any assumptions.

Return WorthFuzzing=false if the patch only contains:
- Modifications to Documentation/, Kconfig files, or code comments.
- Purely decorative changes, such as logging (e.g., pr_err, printk) or tracepoints.
- Changes to numeric constants or macros that do not functionally alter execution flow.
- Code paths that are impossible to reach in virtualized environments like GCE or QEMU,
even when utilizing software-emulated hardware (e.g., usb gadget, mac80211_hwsim).

If it modifies reachable core kernel logic, drivers, or architectures, use your code search
tools to verify the code can be executed, then return WorthFuzzing=true.

When returning WorthFuzzing=true, you MUST ALSO:
1. Extract any specific kernel functions that should be heavily fuzzed into FocusSymbols.
   Avoid listing generic hot-path functions to prevent skewed test distributions.
2. Identify any specific CONFIG_ options required to properly test this new/modified feature.
   Go and look into the Kconfig files and check for ifdefs around the code, do not make assumptions.
   Do not list too generic configs (we already have them enabled). Only list those that
   specifically cover the modified code. List them in the EnableConfigs output array,
   and DO NOT add a '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.

For your convenience, here is the diff of the changes:
commit 58582af80852c31a696b9ada2a9b7141bbd60d8d
Author: syz-cluster <triage@syzkaller.com>
Date:   Tue Jun 30 06:06:01 2026 +0000

    syz-cluster: applied patch under review

diff --git a/net/netfilter/ipset/ip_set_core.c b/net/netfilter/ipset/ip_set_core.c
index a531b654b8d964..6cfad152d7d1ba 100644
--- a/net/netfilter/ipset/ip_set_core.c
+++ b/net/netfilter/ipset/ip_set_core.c
@@ -1480,7 +1480,11 @@ ip_set_dump_done(struct netlink_callback *cb)
 		struct ip_set_net *inst =
 			(struct ip_set_net *)cb->args[IPSET_CB_NET];
 		ip_set_id_t index = (ip_set_id_t)cb->args[IPSET_CB_INDEX];
-		struct ip_set *set = ip_set_ref_netlink(inst, index);
+		struct ip_set *set;
+
+		rcu_read_lock();
+		set = ip_set_ref_netlink(inst, index);
+		rcu_read_unlock();
 
 		if (set->variant->uref)
 			set->variant->uref(set, cb, false);
@@ -1686,7 +1690,9 @@ ip_set_dump_do(struct sk_buff *skb, struct netlink_callback *cb)
 release_refcount:
 	/* If there was an error or set is done, release set */
 	if (ret || !cb->args[IPSET_CB_ARG0]) {
+		rcu_read_lock();
 		set = ip_set_ref_netlink(inst, index);
+		rcu_read_unlock();
 		if (set->variant->uref)
 			set->variant->uref(set, cb, false);
 		pr_debug("release set %s\n", set->name);
diff --git a/net/netfilter/nf_conntrack_expect.c b/net/netfilter/nf_conntrack_expect.c
index 38630c5e006f08..7ae68d60586a23 100644
--- a/net/netfilter/nf_conntrack_expect.c
+++ b/net/netfilter/nf_conntrack_expect.c
@@ -306,7 +306,7 @@ struct nf_conntrack_expect *nf_ct_expect_alloc(struct nf_conn *me)
 {
 	struct nf_conntrack_expect *new;
 
-	new = kmem_cache_alloc(nf_ct_expect_cachep, GFP_ATOMIC);
+	new = kmem_cache_zalloc(nf_ct_expect_cachep, GFP_ATOMIC);
 	if (!new)
 		return NULL;
 
@@ -391,6 +391,7 @@ void nf_ct_expect_init(struct nf_conntrack_expect *exp, unsigned int class,
 #if IS_ENABLED(CONFIG_NF_NAT)
 	memset(&exp->saved_addr, 0, sizeof(exp->saved_addr));
 	memset(&exp->saved_proto, 0, sizeof(exp->saved_proto));
+	exp->dir = 0;
 #endif
 }
 EXPORT_SYMBOL_GPL(nf_ct_expect_init);
diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c
index 4217715d42dc24..31cbb1b55b9e6c 100644
--- a/net/netfilter/nf_conntrack_netlink.c
+++ b/net/netfilter/nf_conntrack_netlink.c
@@ -3549,8 +3549,6 @@ ctnetlink_alloc_expect(const struct nlattr * const cda[], struct nf_conn *ct,
 	if (cda[CTA_EXPECT_FLAGS]) {
 		exp->flags = ntohl(nla_get_be32(cda[CTA_EXPECT_FLAGS]));
 		exp->flags &= ~NF_CT_EXPECT_USERSPACE;
-	} else {
-		exp->flags = 0;
 	}
 	if (cda[CTA_EXPECT_FN]) {
 		const char *name = nla_data(cda[CTA_EXPECT_FN]);
@@ -3562,8 +3560,7 @@ ctnetlink_alloc_expect(const struct nlattr * const cda[], struct nf_conn *ct,
 			goto err_out;
 		}
 		exp->expectfn = expfn->expectfn;
-	} else
-		exp->expectfn = NULL;
+	}
 
 	exp->class = class;
 	exp->master = ct;
@@ -3583,12 +3580,6 @@ ctnetlink_alloc_expect(const struct nlattr * const cda[], struct nf_conn *ct,
 						 exp, nf_ct_l3num(ct));
 		if (err < 0)
 			goto err_out;
-#if IS_ENABLED(CONFIG_NF_NAT)
-	} else {
-		memset(&exp->saved_addr, 0, sizeof(exp->saved_addr));
-		memset(&exp->saved_proto, 0, sizeof(exp->saved_proto));
-		exp->dir = 0;
-#endif
 	}
 	return exp;
 err_out:
diff --git a/net/netfilter/nf_conntrack_sip.c b/net/netfilter/nf_conntrack_sip.c
index 5ec3a4a4bbd707..f3f90a86633894 100644
--- a/net/netfilter/nf_conntrack_sip.c
+++ b/net/netfilter/nf_conntrack_sip.c
@@ -956,7 +956,6 @@ static int set_expected_rtp_rtcp(struct sk_buff *skb, unsigned int protoff,
 			return NF_ACCEPT;
 		saddr = &ct->tuplehash[!dir].tuple.src.u3;
 	} else if (sip_external_media) {
-		struct net_device *dev = skb_dst(skb)->dev;
 		struct dst_entry *dst = NULL;
 		struct flowi fl;
 
@@ -978,7 +977,11 @@ static int set_expected_rtp_rtcp(struct sk_buff *skb, unsigned int protoff,
 		 * through the same interface as the signalling peer.
 		 */
 		if (dst) {
-			bool external_media = (dst->dev == dev);
+			const struct dst_entry *this_dst = skb_dst(skb);
+			bool external_media = false;
+
+			if (this_dst && dst->dev == this_dst->dev)
+				external_media = true;
 
 			dst_release(dst);
 			if (external_media)
diff --git a/net/netfilter/nfnetlink_cthelper.c b/net/netfilter/nfnetlink_cthelper.c
index f1460b683d7af7..2cbcca9110dbf5 100644
--- a/net/netfilter/nfnetlink_cthelper.c
+++ b/net/netfilter/nfnetlink_cthelper.c
@@ -163,6 +163,8 @@ nfnl_cthelper_expect_policy(struct nf_conntrack_expect_policy *expect_policy,
 		    tb[NFCTH_POLICY_NAME], NF_CT_HELPER_NAME_LEN);
 	expect_policy->max_expected =
 		ntohl(nla_get_be32(tb[NFCTH_POLICY_EXPECT_MAX]));
+	if (!expect_policy->max_expected)
+		expect_policy->max_expected = NF_CT_EXPECT_MAX_CNT;
 	if (expect_policy->max_expected > NF_CT_EXPECT_MAX_CNT)
 		return -EINVAL;
 
diff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c
index 80ca077b81bd5a..35d4c6c628ffc1 100644
--- a/net/netfilter/nfnetlink_queue.c
+++ b/net/netfilter/nfnetlink_queue.c
@@ -1184,6 +1184,173 @@ nfqnl_enqueue_packet(struct nf_queue_entry *entry, unsigned int queuenum)
 	return err;
 }
 
+static bool nfqnl_validate_ipopts(const struct iphdr *iph_new,
+				  const struct nf_queue_entry *e)
+{
+	const struct iphdr *iph_orig = ip_hdr(e->skb);
+	unsigned int ihl = iph_new->ihl * 4;
+
+	if (iph_new->ihl != iph_orig->ihl)
+		return false;
+	if (ihl == sizeof(*iph_orig))
+		return true;
+
+	return memcmp(iph_new + 1, ip_hdr(e->skb) + 1, ihl - sizeof(*iph_orig)) == 0;
+}
+
+static bool nfqnl_validate_ip4(const struct iphdr *iph, unsigned int data_len,
+			       const struct nf_queue_entry *e)
+{
+	unsigned int ihl;
+
+	if (data_len < sizeof(*iph))
+		return false;
+
+	ihl = iph->ihl * 4u;
+	if (ihl < sizeof(*iph) || data_len < ihl)
+		return false;
+
+	if (iph->version != 4 ||
+	    ((iph->frag_off ^ ip_hdr(e->skb)->frag_off) & ~htons(IP_DF)) != 0)
+		return false;
+
+	/* BIG TCP won't work; netlink attr len is u16 */
+	if (ntohs(iph->tot_len) != data_len)
+		return false;
+
+	/* support for ipopts mangling would require
+	 * recompile + skb transport header update.
+	 */
+	return nfqnl_validate_ipopts(iph, e);
+}
+
+static bool nfqnl_validate_one_exthdr(const u8 *data,
+				      unsigned int data_len,
+				      const struct nf_queue_entry *e,
+				      int start, int hdrlen)
+{
+	u16 octets;
+
+	if (data_len < hdrlen || hdrlen < 2)
+		return false;
+
+	while (hdrlen > 0) {
+		if (data_len < sizeof(octets))
+			return false;
+		data_len -= sizeof(octets);
+
+		if (skb_copy_bits(e->skb, start, &octets, sizeof(octets)))
+			return false;
+
+		if (hdrlen < sizeof(octets))
+			return false;
+
+		hdrlen -= sizeof(octets);
+		if (memcmp(data, &octets, sizeof(octets)))
+			return false;
+
+		start += sizeof(octets);
+		data += sizeof(octets);
+	}
+
+	return true;
+}
+
+static bool nfqnl_validate_exthdr(const struct ipv6hdr *ip6_new,
+				  unsigned int data_len,
+				  const struct nf_queue_entry *e)
+{
+	const struct ipv6hdr *ip6_orig = ipv6_hdr(e->skb);
+	int exthdr_cnt = 0, start = sizeof(*ip6_orig);
+	const u8 *data = (const u8 *)ip6_new;
+	u8 orig_nexthdr = ip6_orig->nexthdr;
+	u8 new_nexthdr = ip6_new->nexthdr;
+
+	if (new_nexthdr != orig_nexthdr)
+		return false;
+
+	data += sizeof(*ip6_new);
+	data_len -= sizeof(*ip6_new);
+
+	while (ipv6_ext_hdr(orig_nexthdr)) {
+		const struct ipv6_opt_hdr *hp;
+		struct ipv6_opt_hdr _hdr;
+		int hdrlen;
+
+		if (orig_nexthdr == NEXTHDR_NONE)
+			return true;
+
+		if (unlikely(exthdr_cnt++ >= IP6_MAX_EXT_HDRS_CNT))
+			return false;
+
+		hp = skb_header_pointer(e->skb, start, sizeof(_hdr), &_hdr);
+		if (!hp)
+			return false;
+
+		switch (orig_nexthdr) {
+		case NEXTHDR_FRAGMENT:
+			hdrlen = sizeof(struct frag_hdr);
+			break;
+		case NEXTHDR_AUTH:
+			hdrlen = ipv6_authlen(hp);
+			break;
+		default:
+			hdrlen = ipv6_optlen(hp);
+			break;
+		}
+
+		if (!nfqnl_validate_one_exthdr(data, data_len, e,
+					       start, hdrlen))
+			return false;
+
+		orig_nexthdr = hp->nexthdr;
+		hp = (const void *)data;
+		new_nexthdr = hp->nexthdr;
+
+		if (new_nexthdr != orig_nexthdr)
+			return false;
+
+		data_len -= hdrlen;
+		start += hdrlen;
+		data += hdrlen;
+	}
+
+	return true;
+}
+
+static bool nfqnl_validate_ip6(const struct ipv6hdr *ip6, unsigned int data_len,
+			       const struct nf_queue_entry *e)
+{
+	if (data_len < sizeof(*ip6))
+		return false;
+
+	/* BIG TCP/jumbograms won't work; netlink attr len is u16 */
+	if (ntohs(ip6->payload_len) != data_len - sizeof(*ip6))
+		return false;
+
+	if (ip6->version != 6)
+		return false;
+
+	return nfqnl_validate_exthdr(ip6, data_len, e);
+}
+
+static bool nfqnl_validate_write(const void *data, unsigned int data_len,
+				 const struct nf_queue_entry *e)
+{
+	switch (e->state.pf) {
+	case NFPROTO_IPV4:
+		return nfqnl_validate_ip4(data, data_len, e);
+	case NFPROTO_IPV6:
+		return nfqnl_validate_ip6(data, data_len, e) &&
+		       !(IP6CB(e->skb)->flags & IP6SKB_JUMBOGRAM);
+	case NFPROTO_BRIDGE:
+		/* No write support. Bridge is dubious: userspace doesn't even see L2 header */
+		return false;
+	}
+
+	return false;
+}
+
 static int
 nfqnl_mangle(void *data, unsigned int data_len, struct nf_queue_entry *e, int diff)
 {
@@ -1192,6 +1359,9 @@ nfqnl_mangle(void *data, unsigned int data_len, struct nf_queue_entry *e, int di
 	if (e->state.net->user_ns != &init_user_ns)
 		return -EPERM;
 
+	if (!nfqnl_validate_write(data, data_len, e))
+		return -EINVAL;
+
 	if (diff < 0) {
 		unsigned int min_len = skb_transport_offset(e->skb);
 
diff --git a/net/netfilter/nft_fib.c b/net/netfilter/nft_fib.c
index e048f05694cddd..89555380f1c5a0 100644
--- a/net/netfilter/nft_fib.c
+++ b/net/netfilter/nft_fib.c
@@ -31,6 +31,15 @@ int nft_fib_validate(const struct nft_ctx *ctx, const struct nft_expr *expr)
 	const struct nft_fib *priv = nft_expr_priv(expr);
 	unsigned int hooks;
 
+	switch (ctx->family) {
+	case NFPROTO_IPV4:
+	case NFPROTO_IPV6:
+	case NFPROTO_INET:
+		break;
+	default:
+		return -EOPNOTSUPP;
+	}
+
 	switch (priv->result) {
 	case NFT_FIB_RESULT_OIF:
 	case NFT_FIB_RESULT_OIFNAME:
diff --git a/net/netfilter/nft_fib_netdev.c b/net/netfilter/nft_fib_netdev.c
index 3f3478abd84546..5774a754402780 100644
--- a/net/netfilter/nft_fib_netdev.c
+++ b/net/netfilter/nft_fib_netdev.c
@@ -50,6 +50,33 @@ static void nft_fib_netdev_eval(const struct nft_expr *expr,
 	regs->verdict.code = NFT_BREAK;
 }
 
+static int nft_fib_netdev_validate(const struct nft_ctx *ctx,
+				   const struct nft_expr *expr)
+{
+	const struct nft_fib *priv = nft_expr_priv(expr);
+	unsigned int hooks;
+
+	switch (priv->result) {
+	case NFT_FIB_RESULT_OIF:
+	case NFT_FIB_RESULT_OIFNAME:
+		hooks = (1 << NF_NETDEV_INGRESS);
+		break;
+	case NFT_FIB_RESULT_ADDRTYPE:
+		if (priv->flags & NFTA_FIB_F_IIF)
+			hooks = (1 << NF_NETDEV_INGRESS);
+		else if (priv->flags & NFTA_FIB_F_OIF)
+			hooks = (1 << NF_NETDEV_EGRESS);
+		else
+			hooks = (1 << NF_NETDEV_INGRESS) |
+				(1 << NF_NETDEV_EGRESS);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return nft_chain_validate_hooks(ctx->chain, hooks);
+}
+
 static struct nft_expr_type nft_fib_netdev_type;
 static const struct nft_expr_ops nft_fib_netdev_ops = {
 	.type		= &nft_fib_netdev_type,
@@ -57,7 +84,7 @@ static const struct nft_expr_ops nft_fib_netdev_ops = {
 	.eval		= nft_fib_netdev_eval,
 	.init		= nft_fib_init,
 	.dump		= nft_fib_dump,
-	.validate	= nft_fib_validate,
+	.validate	= nft_fib_netdev_validate,
 };
 
 static struct nft_expr_type nft_fib_netdev_type __read_mostly = {
diff --git a/net/netfilter/nft_payload.c b/net/netfilter/nft_payload.c
index 345eff140d56f8..391539a1ceaa77 100644
--- a/net/netfilter/nft_payload.c
+++ b/net/netfilter/nft_payload.c
@@ -834,6 +834,249 @@ nft_payload_set_vlan(const u32 *src, struct sk_buff *skb, u16 offset, u8 len,
 	return true;
 }
 
+/* Ingress is very early, before l3 protocol handlers.
+ * There should be no in-tree code that trusts l3/l4 headers
+ * between ingress and NF_INET_PRE_ROUTING hooks.
+ */
+static bool nft_in_ingress(const struct nf_hook_state *s)
+{
+	return s->pf == NFPROTO_NETDEV && s->hook == NF_NETDEV_INGRESS;
+}
+
+static bool nft_nh_write_ok_ip4(const struct nft_pktinfo *pkt,
+				const struct nft_payload_set *priv,
+				const u32 *src)
+{
+	unsigned int offset = priv->offset + skb_network_offset(pkt->skb);
+	const u8 *new_octets = (const u8 *)src;
+	u8 old_octet;
+
+	switch (priv->offset) {
+	case 0: /* csum fixups does expand dscp/tos store to 2 bytes.
+		 * make sure ihl/version remain unchanged.
+		 */
+		if (skb_copy_bits(pkt->skb, offset, &old_octet, sizeof(old_octet)))
+			return false;
+
+		return priv->len == 2 &&
+		       *new_octets == old_octet;
+	case offsetof(struct iphdr, tos):
+		return priv->len == 1;
+	case offsetof(struct iphdr, id):
+		return priv->len == 2;
+	case offsetof(struct iphdr, ttl):
+		if (priv->len == 1)
+			return true;
+
+		if (priv->len != 2)
+			return false;
+
+		/* same, csum fixup does expand ttl store to two bytes.
+		 * check protocol is not altered.
+		 */
+		if (skb_copy_bits(pkt->skb, offset + 1, &old_octet, sizeof(old_octet)))
+			return false;
+
+		return new_octets[1] == old_octet;
+	case offsetof(struct iphdr, check):
+		return priv->len <= 2 + 4 + 4;
+	case offsetof(struct iphdr, saddr):
+		return priv->len <= 4 + 4;
+	case offsetof(struct iphdr, daddr):
+		return priv->len <= 4;
+	}
+
+	return false;
+}
+
+static bool nft_nh_write_ok_ip6(const struct nft_pktinfo *pkt,
+				const struct nft_payload_set *priv,
+				const u32 *src)
+{
+	const struct ipv6hdr *ih = (const void *)src;
+
+	switch (priv->offset) {
+	case 0: /* store to dscp must not alter ip6 version */
+		return priv->len <= 4 && ih->version == 6;
+	case 2:
+		return priv->len <= 2;
+	case offsetof(struct ipv6hdr, hop_limit):
+		return priv->len == 1;
+	case offsetof(struct ipv6hdr, saddr):
+		return priv->len <= 16 + 16;
+	case offsetof(struct ipv6hdr, daddr):
+		return priv->len <= 16;
+	}
+
+	return false;
+}
+
+static bool nft_nh_write_ok_arp(const struct nft_payload_set *priv)
+{
+	/* Variable size for standard ethernet arp */
+	const unsigned int eth_ip = 2 * (ETH_ALEN + 4);
+	unsigned int offset = priv->offset;
+
+	switch (offset) {
+	case offsetof(struct arphdr, ar_op):
+		return priv->len == 2;
+	default:
+		break;
+	}
+
+	/* permit writes post fixed arp header size. offset + len are
+	 * checked vs skb size via skb_ensure_writable.
+	 */
+	return offset >= sizeof(struct arphdr) && priv->len <= eth_ip;
+}
+
+static bool nft_nh_write_ok_netdev(const struct nft_pktinfo *pkt,
+				   const struct nft_payload_set *priv,
+				   const u32 *src)
+{
+#ifdef CONFIG_NF_TABLES_NETDEV
+	switch (pkt->skb->protocol) {
+	case htons(ETH_P_ARP):
+		return nft_nh_write_ok_arp(priv);
+	case htons(ETH_P_IP):
+		return nft_nh_write_ok_ip4(pkt, priv, src);
+	case htons(ETH_P_IPV6):
+		return nft_nh_write_ok_ip6(pkt, priv, src);
+	}
+#endif
+	/* default to false for now, relax later in case we have
+	 * use-cases that need inner header manipulation for
+	 * encapsulated traffic like vlan or PPPoE.
+	 */
+	return false;
+}
+
+static bool nft_nh_write_ok_bridge(const struct nft_pktinfo *pkt,
+				   const struct nft_payload_set *priv,
+				   const u32 *src)
+{
+#if IS_ENABLED(CONFIG_NF_TABLES_BRIDGE)
+	switch (pkt->ethertype) {
+	case htons(ETH_P_ARP):
+		return nft_nh_write_ok_arp(priv);
+	case htons(ETH_P_IP):
+		return nft_nh_write_ok_ip4(pkt, priv, src);
+	case htons(ETH_P_IPV6):
+		return nft_nh_write_ok_ip6(pkt, priv, src);
+	}
+#endif
+	/* see nft_nh_write_ok_netdev: default to false */
+	return false;
+}
+
+static bool nft_nh_write_ok(const struct nft_pktinfo *pkt,
+			    const struct nft_payload_set *priv,
+			    const u32 *src)
+{
+	switch (pkt->state->pf) {
+	case NFPROTO_ARP:
+		return nft_nh_write_ok_arp(priv);
+	case NFPROTO_BRIDGE:
+		return nft_nh_write_ok_bridge(pkt, priv, src);
+	case NFPROTO_IPV4:
+		return nft_nh_write_ok_ip4(pkt, priv, src);
+	case NFPROTO_IPV6:
+		return nft_nh_write_ok_ip6(pkt, priv, src);
+	case NFPROTO_NETDEV:
+		if (pkt->state->hook == NF_NETDEV_INGRESS)
+			return true;
+		return nft_nh_write_ok_netdev(pkt, priv, src);
+	}
+
+	return false;
+}
+
+/* check linklayer modifications don't spill into network header. */
+static bool nft_ll_write_ok(const struct nft_pktinfo *pkt, int offset)
+{
+	if (nft_in_ingress(pkt->state))
+		return true;
+
+	return offset <= skb_network_offset(pkt->skb);
+}
+
+static bool nft_payload_validate_inet_csum_offset(const struct nft_ctx *ctx,
+						  const struct nft_payload_set *priv)
+{
+	switch (priv->base) {
+	case NFT_PAYLOAD_LL_HEADER:
+		break;
+	case NFT_PAYLOAD_NETWORK_HEADER:
+		if (ctx->family == NFPROTO_IPV4) {
+			if (offsetof(struct iphdr, check) == priv->csum_offset)
+				return true;
+
+			return false;
+		}
+		return true; /* run time validation required */
+	case NFT_PAYLOAD_TRANSPORT_HEADER:
+		if (priv->csum_flags) /* makes no sense, asks for "re-update" of L4 checksum */
+			return false;
+
+		/* no further check here; offset can't be negative so bogus
+		 * offsets can corrupt L4 or payload but not l3 headers.
+		 * We already allow arbitrary l4/inner payload writes.
+		 */
+		return true;
+	case NFT_PAYLOAD_INNER_HEADER:
+		return true;
+	case NFT_PAYLOAD_TUN_HEADER:
+		break;
+	}
+
+	return false;
+}
+
+/* do not allow arbitrary network header mangling via bogus csum_off.
+ * We only support ipv4.  Only NFPROTO_IPV4 can be checked from control
+ * plane.
+ */
+static bool nft_payload_csum_nh_write_ok(const struct nft_payload_set *priv,
+					 const struct nft_pktinfo *pkt)
+{
+	switch (pkt->state->pf) {
+	case NFPROTO_IPV4:
+		/* Warning: NFPROTO_INET was not checked; we can't return true here. */
+		return priv->csum_offset == offsetof(struct iphdr, check);
+	case NFPROTO_IPV6:
+		return false;
+	case NFPROTO_BRIDGE:
+		return pkt->ethertype == htons(ETH_P_IP) &&
+		       priv->csum_offset == offsetof(struct iphdr, check);
+	case NFPROTO_NETDEV:
+		return pkt->skb->protocol == htons(ETH_P_IP) &&
+		       priv->csum_offset == offsetof(struct iphdr, check);
+	}
+
+	return false;
+}
+
+static bool nft_payload_csum_write_ok(const struct nft_pktinfo *pkt,
+				      const struct nft_payload_set *priv)
+{
+	switch (priv->base) {
+	case NFT_PAYLOAD_LL_HEADER:
+		break;
+	case NFT_PAYLOAD_NETWORK_HEADER:
+		return nft_payload_csum_nh_write_ok(priv, pkt);
+	case NFT_PAYLOAD_TRANSPORT_HEADER:
+	case NFT_PAYLOAD_INNER_HEADER:
+		/* neither offsets are validated, offsets cannot be
+		 * negative so real l3 headers cannot be mangled.
+		 */
+		return true;
+	case NFT_PAYLOAD_TUN_HEADER:
+		break;
+	}
+
+	return false;
+}
+
 static void nft_payload_set_eval(const struct nft_expr *expr,
 				 struct nft_regs *regs,
 				 const struct nft_pktinfo *pkt)
@@ -861,8 +1104,12 @@ static void nft_payload_set_eval(const struct nft_expr *expr,
 		}
 
 		offset = skb_mac_header(skb) - skb->data - vlan_hlen;
+		if (!nft_ll_write_ok(pkt, priv->len + priv->offset + offset))
+			goto err;
 		break;
 	case NFT_PAYLOAD_NETWORK_HEADER:
+		if (!nft_nh_write_ok(pkt, priv, src))
+			goto err;
 		offset = skb_network_offset(skb);
 		break;
 	case NFT_PAYLOAD_TRANSPORT_HEADER:
@@ -894,6 +1141,7 @@ static void nft_payload_set_eval(const struct nft_expr *expr,
 		tsum = csum_partial(src, priv->len, 0);
 
 		if (priv->csum_type == NFT_PAYLOAD_CSUM_INET &&
+		    nft_payload_csum_write_ok(pkt, priv) &&
 		    nft_payload_csum_inet(skb, src, fsum, tsum, csum_offset))
 			goto err;
 
@@ -960,7 +1208,26 @@ static int nft_payload_set_init(const struct nft_ctx *ctx,
 
 	switch (csum_type) {
 	case NFT_PAYLOAD_CSUM_NONE:
+		if (priv->csum_offset) /* nonsensical */
+			return -EINVAL;
+
+		if (priv->csum_flags == 0)
+			break;
+
+		/* Userspace requests L4 checksum update, e.g.:
+		 * - IPv6 stateless NAT (no l3 csum)
+		 * - transport header mangling
+		 * - inner data mangling
+		 */
+		if (priv->base == NFT_PAYLOAD_NETWORK_HEADER ||
+		    priv->base == NFT_PAYLOAD_TRANSPORT_HEADER ||
+		    priv->base == NFT_PAYLOAD_INNER_HEADER)
+			break;
+
+		return -EINVAL;
 	case NFT_PAYLOAD_CSUM_INET:
+		if (!nft_payload_validate_inet_csum_offset(ctx, priv))
+			return -EINVAL;
 		break;
 	case NFT_PAYLOAD_CSUM_SCTP:
 		if (priv->base != NFT_PAYLOAD_TRANSPORT_HEADER)
@@ -968,6 +1235,9 @@ static int nft_payload_set_init(const struct nft_ctx *ctx,
 
 		if (priv->csum_offset != offsetof(struct sctphdr, checksum))
 			return -EINVAL;
+
+		if (priv->csum_flags)
+			return -EINVAL;
 		break;
 	default:
 		return -EOPNOTSUPP;
diff --git a/net/netfilter/nft_set_pipapo.c b/net/netfilter/nft_set_pipapo.c
index 706c78853f245b..978bb0c0110682 100644
--- a/net/netfilter/nft_set_pipapo.c
+++ b/net/netfilter/nft_set_pipapo.c
@@ -342,6 +342,8 @@
 #include "nft_set_pipapo_avx2.h"
 #include "nft_set_pipapo.h"
 
+static void nft_pipapo_abort(const struct nft_set *set);
+
 /**
  * pipapo_refill() - For each set bit, set bits from selected mapping table item
  * @map:	Bitmap to be scanned for set bits
@@ -1296,7 +1298,7 @@ static int nft_pipapo_insert(const struct net *net, const struct nft_set *set,
 	const u8 *start_p, *end_p;
 	int i, bsize_max, err = 0;
 
-	if (!m)
+	if (!m || m->state == NFT_PIPAPO_CLONE_ERR)
 		return -ENOMEM;
 
 	if (nft_set_ext_exists(ext, NFT_SET_EXT_KEY_END))
@@ -1367,8 +1369,10 @@ static int nft_pipapo_insert(const struct net *net, const struct nft_set *set,
 		else
 			ret = pipapo_expand(f, start, end, f->groups * f->bb);
 
-		if (ret < 0)
-			return ret;
+		if (ret < 0) {
+			err = ret;
+			goto abort;
+		}
 
 		if (f->bsize > bsize_max)
 			bsize_max = f->bsize;
@@ -1384,7 +1388,7 @@ static int nft_pipapo_insert(const struct net *net, const struct nft_set *set,
 
 		err = pipapo_realloc_scratch(m, bsize_max);
 		if (err)
-			return err;
+			goto abort;
 
 		m->bsize_max = bsize_max;
 	} else {
@@ -1396,7 +1400,26 @@ static int nft_pipapo_insert(const struct net *net, const struct nft_set *set,
 
 	pipapo_map(m, rulemap, e);
 
+	m->state = NFT_PIPAPO_CLONE_MOD;
 	return 0;
+abort:
+	DEBUG_NET_WARN_ON_ONCE(m->state == NFT_PIPAPO_CLONE_ERR);
+
+	/* Two rollback cases:
+	 * 1) no previous changes.  nft_pipapo_abort is not
+	 * guaranteed to be invoked (there might be no further
+	 * add/delete requests coming after this).
+	 *
+	 * 2) we had previous changes: there are transaction
+	 * records pointing to this set.  Leave the rollback to
+	 * the transaction handling.
+	 */
+	if (m->state == NFT_PIPAPO_CLONE_NEW)
+		nft_pipapo_abort(set); /* releases m */
+	else
+		m->state = NFT_PIPAPO_CLONE_ERR;
+
+	return err;
 }
 
 /**
@@ -1473,6 +1496,7 @@ static struct nft_pipapo_match *pipapo_clone(struct nft_pipapo_match *old)
 		dst++;
 	}
 
+	new->state = NFT_PIPAPO_CLONE_NEW;
 	return new;
 
 out_mt:
@@ -1896,7 +1920,7 @@ nft_pipapo_deactivate(const struct net *net, const struct nft_set *set,
 	/* removal must occur on priv->clone, if we are low on memory
 	 * we have no choice and must fail the removal request.
 	 */
-	if (!m)
+	if (!m || m->state == NFT_PIPAPO_CLONE_ERR)
 		return NULL;
 
 	e = pipapo_get(m, (const u8 *)elem->key.val.data,
diff --git a/net/netfilter/nft_set_pipapo.h b/net/netfilter/nft_set_pipapo.h
index b82abb03576edd..a19e980d06ef42 100644
--- a/net/netfilter/nft_set_pipapo.h
+++ b/net/netfilter/nft_set_pipapo.h
@@ -131,9 +131,16 @@ struct nft_pipapo_scratch {
 	unsigned long __map[];
 };
 
+enum nft_pipapo_clone_state {
+	NFT_PIPAPO_CLONE_NEW,
+	NFT_PIPAPO_CLONE_MOD,
+	NFT_PIPAPO_CLONE_ERR,
+};
+
 /**
  * struct nft_pipapo_match - Data used for lookup and matching
  * @field_count:	Amount of fields in set
+ * @state:		add/delete state; used from control plane
  * @bsize_max:		Maximum lookup table bucket size of all fields, in longs
  * @scratch:		Preallocated per-CPU maps for partial matching results
  * @rcu:		Matching data is swapped on commits
@@ -141,6 +148,7 @@ struct nft_pipapo_scratch {
  */
 struct nft_pipapo_match {
 	u8 field_count;
+	enum nft_pipapo_clone_state state:8;
 	unsigned int bsize_max;
 	struct nft_pipapo_scratch * __percpu *scratch;
 	struct rcu_head rcu;

gemini-3.1-pro-preview

							input: 11600
							output: 34
							thoughts: 608

**Patch Series Evaluation: A Fuzzing Opportunity**

Okay, so I've got this patch series in front of me, and my immediate thought is *yes, this deserves a thorough fuzzing campaign.* It's touching quite a few critical areas of the `netfilter` subsystem: specifically, a dive into netlink queue, some changes to nftables payload mangling, the handling of pipapo sets, and conntrack expectations. Given the scope and the types of modifications, from locking changes in `ip_set_core.c` (that `rcu_read_lock`/`unlock` is interesting) to various initialization and validation adjustments across multiple files, the potential for subtle bugs is definitely there.

It's clear that this touches on various core network filtering components. In `nf_conntrack_expect.c` the change to `zalloc` with added initialization raises immediate concerns. The changes related to the SIP helper (`nf_conntrack_sip.c`) sound important, as do the validations added in `nfnetlink_queue.c` and `nft_*` files. The state tracking added to `nft_set_pipapo.c` looks like an area where subtle race conditions or unexpected state transitions could arise.

Now, before we jump into the fuzzing, we need to make sure we've got the right kernel configurations enabled. Let's see... we'll definitely need `CONFIG_NETFILTER`, naturally. Beyond that, I'm thinking `CONFIG_NF_CONNTRACK`, `CONFIG_NF_CONNTRACK_SIP`, `CONFIG_NF_CT_NETLINK`, `CONFIG_NETFILTER_NETLINK_QUEUE`, `CONFIG_NF_TABLES`, and the `CONFIG_NFT_*` options, so `CONFIG_NFT_FIB`, `CONFIG_NFT_FIB_NETDEV`, `CONFIG_NFT_PAYLOAD`, and I also saw some `IP_SET` references, so we need `CONFIG_IP_SET`. We must ensure these are enabled so the fuzzer can properly test these changes.

I'll quickly do some code searching to verify these dependencies and then get the fuzzing environment setup. This looks like it'll be a fruitful fuzzing campaign!

{
  "Expression": "config NF_CONNTRACK_SIP",
  "PathPrefix": "net/netfilter/Kconfig"
}

{
  "Output": "net/netfilter/Kconfig=330=config NF_CONNTRACK_SANE\n--\nnet/netfilter/Kconfig-342-\nnet/netfilter/Kconfig:343:config NF_CONNTRACK_SIP\nnet/netfilter/Kconfig-344-\ttristate \"SIP protocol support\"\n"
}

gemini-3.1-pro-preview

							input: 12805
							output: 35
							thoughts: 15

Okay, here's my interpretation of that thought process, assuming I'm deep in the weeds of kernel networking, maybe debugging a performance issue or setting up some advanced firewall rules:

**Netfilter and Netlink Queue Check**

Alright, before I dive too deep into this packet filtering mess, I need to make absolutely sure the basics are in place. The whole Netfilter setup relies heavily on the netlink queueing mechanism for user-space interaction. So, before I start pulling my hair out trying to debug some weird traffic behaviour or missing packets, let's just do a quick sanity check: I need to verify that `CONFIG_NETFILTER_NETLINK_QUEUE` is enabled. It's such a fundamental component, and I've been bitten by forgetting to check this before – wasting hours trying to figure out why my custom rules aren't being hit. This is my foundation; I need to make sure it's solid before building anything on top of it. One missing config option can derail the whole operation. Let's make sure that netlink queue is enabled, and then I can proceed.

{
  "Expression": "config NETFILTER_NETLINK_QUEUE",
  "PathPrefix": "net/netfilter/Kconfig"
}

{
  "Output": "net/netfilter/Kconfig=46=config NETFILTER_NETLINK_ACCT\n--\nnet/netfilter/Kconfig-53-\nnet/netfilter/Kconfig:54:config NETFILTER_NETLINK_QUEUE\nnet/netfilter/Kconfig-55-\ttristate \"Netfilter NFQUEUE over NFNETLINK interface\"\n"
}

gemini-3.1-pro-preview

							input: 13178
							output: 32
							thoughts: 12

Here's my thought process, as requested:

**Checking `CONFIG_NFT_FIB` for Netfilter Functionality**

Okay, first things first, I need to verify if the `CONFIG_NFT_FIB` option is enabled. I know this is crucial for enabling the FIB (Forwarding Information Base) support within Netfilter's nftables framework. Without this, I won't have the necessary foundation for advanced routing and packet filtering capabilities that I'm likely trying to implement. I need to make sure this is enabled to proceed with whatever task is at hand. This is a foundational step, and neglecting it could lead to hours of wasted effort chasing phantom problems. Time to check the configuration...

{
  "Expression": "config NFT_FIB",
  "PathPrefix": "net/netfilter/Kconfig"
}

{
  "Output": "net/netfilter/Kconfig=599=config NFT_HASH\n--\nnet/netfilter/Kconfig-604-\nnet/netfilter/Kconfig:605:config NFT_FIB\nnet/netfilter/Kconfig-606-\ttristate\nnet/netfilter/Kconfig-607-\nnet/netfilter/Kconfig:608:config NFT_FIB_INET\nnet/netfilter/Kconfig-609-\tdepends on NF_TABLES_INET\n--\nnet/netfilter/Kconfig=674=config NFT_FWD_NETDEV\n--\nnet/netfilter/Kconfig-679-\nnet/netfilter/Kconfig:680:config NFT_FIB_NETDEV\nnet/netfilter/Kconfig-681-\tdepends on NFT_FIB_IPV4\n"
}

gemini-3.1-pro-preview

							input: 13586
							output: 32
							thoughts: 12

Here's my take on those thoughts:

**Evaluating `CONFIG_NFT_PAYLOAD`**

Okay, so I'm thinking, let's just make sure we're on top of `CONFIG_NFT_PAYLOAD`. It's a key element, obviously. It dictates how we're going to interact with the payload within the context of nftables, and that's critical for our overall performance and security profile. Is this enabled? Is it correctly configured? Are there any dependencies I need to consider? I need to quickly assess its current status and make sure it aligns with the overall requirements of the system's intended behavior, particularly considering the network traffic analysis and manipulation that's going on here. It's a fundamental setting, so I want to ensure it's set up correctly.

{
  "Expression": "config NFT_PAYLOAD",
  "PathPrefix": "net/netfilter/Kconfig"
}

{
  "error": "no matches"
}

gemini-3.1-pro-preview

							input: 13813
							output: 29
							thoughts: 46

Here's my thought process, summarized as you requested:

**Navigating the Netfilter Build Process**

Okay, so I'm digging into this `nft_payload.c` file and I'm pretty sure it's being compiled into the kernel conditionally, specifically depending on the Netfilter configuration. My intuition says `CONFIG_NF_TABLES` is likely the key trigger, but it could be something else entirely. I've got to confirm this. The most logical place to start digging would be the Netfilter `Makefile`, in `net/netfilter/`. That's where all the build rules for this stuff would be defined, so let's jump in there and see what the build process is actually doing with `nft_payload.c`. Hopefully, it'll be clear pretty quickly whether it's unconditionally built with a specific config or if there are other dependencies at play.

{
  "Expression": "nft_payload",
  "PathPrefix": "net/netfilter/Makefile"
}

{
  "Output": "net/netfilter/Makefile=87=nf_tables-objs := nf_tables_core.o nf_tables_api.o nft_chain_filter.o \\\nnet/netfilter/Makefile-88-\t\t  nf_tables_trace.o nft_immediate.o nft_cmp.o nft_range.o \\\nnet/netfilter/Makefile:89:\t\t  nft_bitwise.o nft_byteorder.o nft_payload.o nft_lookup.o \\\nnet/netfilter/Makefile-90-\t\t  nft_dynset.o nft_meta.o nft_rt.o nft_exthdr.o nft_last.o \\\n"
}

gemini-3.1-pro-preview

							input: 14240
							output: 32
							thoughts: 43

Okay, here's my interpretation of those thoughts, summarized from my perspective as an expert in the field:

**Assessing Configuration Dependencies**

Alright, so `nft_payload.o` is definitely a component within `nf_tables-objs`. That confirms that having `CONFIG_NF_TABLES` enabled covers the dependencies for that particular object file. No need to dig any deeper there. However, it looks like I should check on `nft_set_pipapo`. I need to assess what its dependencies are, and whether or not enabling `CONFIG_NF_TABLES` sufficiently addresses those too. I'm seeing it for the first time, and I need to determine if there are any other specific configurations I need to take care of in conjunction with the base `nf_tables` config.

{
  "Expression": "nft_set_pipapo",
  "PathPrefix": "net/netfilter/Makefile"
}

{
  "Output": "net/netfilter/Makefile=87=nf_tables-objs := nf_tables_core.o nf_tables_api.o nft_chain_filter.o \\\n--\nnet/netfilter/Makefile-93-\t\t  nft_set_hash.o nft_set_bitmap.o nft_set_rbtree.o \\\nnet/netfilter/Makefile:94:\t\t  nft_set_pipapo.o\nnet/netfilter/Makefile-95-\n--\nnet/netfilter/Makefile=97=ifndef CONFIG_UML\nnet/netfilter/Makefile:98:nf_tables-objs += nft_set_pipapo_avx2.o\nnet/netfilter/Makefile-99-endif\n"
}

gemini-3.1-pro-preview

							input: 14662
							output: 32
							thoughts: 22

Here's my summary, as though I'm thinking through this myself:

**Considering Dependencies and Related Modules**

Okay, so I'm looking at this `nf_tables-objs` thing. Right, that's definitely a key component. But, I need to zoom out a bit. What else is in play here? Specifically, I'm wondering about `nfnetlink_cthelper`. Is it directly related? Is it a dependency? Or is it something that interacts with `nf_tables-objs` in some other significant way? I need to understand its role in the overall picture, if any. Digging into the relationships here will paint a better picture.

{
  "Expression": "nfnetlink_cthelper",
  "PathPrefix": "net/netfilter/Makefile"
}

{
  "Output": "net/netfilter/Makefile=38=obj-$(CONFIG_NF_CT_NETLINK_TIMEOUT) += nfnetlink_cttimeout.o\nnet/netfilter/Makefile:39:obj-$(CONFIG_NF_CT_NETLINK_HELPER) += nfnetlink_cthelper.o\nnet/netfilter/Makefile-40-\n"
}

gemini-3.1-pro-preview

							input: 14950
							output: 33
							thoughts: 28

Okay, here's my take on those thoughts, framed as an expert's internal monologue:

**Navigating the Kernel Configuration Labyrinth**

Alright, so the task at hand requires `CONFIG_NF_CT_NETLINK_HELPER`. That's the baseline, the core functionality we need to get rolling. Now, before I dive too deep into the specific implementation, I'm going to take a moment to double-check something that often intersects with this area – specifically, `CONFIG_IP_SET`. It's a key piece of the puzzle, and often a prerequisite or at least a related feature. Let's make sure it’s enabled or at least understood in this context before I proceed. I need to understand its relationship to the netlink helper.

{
  "Expression": "config IP_SET",
  "PathPrefix": "net/netfilter/ipset/Kconfig"
}

{
  "Output": "net/netfilter/ipset/Kconfig-1-# SPDX-License-Identifier: GPL-2.0-only\nnet/netfilter/ipset/Kconfig:2:menuconfig IP_SET\nnet/netfilter/ipset/Kconfig-3-\ttristate \"IP set support\"\n--\nnet/netfilter/ipset/Kconfig=14=if IP_SET\nnet/netfilter/ipset/Kconfig-15-\nnet/netfilter/ipset/Kconfig:16:config IP_SET_MAX\nnet/netfilter/ipset/Kconfig-17-\tint \"Maximum number of IP sets\"\n--\nnet/netfilter/ipset/Kconfig-27-\nnet/netfilter/ipset/Kconfig:28:config IP_SET_BITMAP_IP\nnet/netfilter/ipset/Kconfig-29-\ttristate \"bitmap:ip set support\"\n--\nnet/netfilter/ipset/Kconfig-36-\nnet/netfilter/ipset/Kconfig:37:config IP_SET_BITMAP_IPMAC\nnet/netfilter/ipset/Kconfig-38-\ttristate \"bitmap:ip,mac set support\"\n--\nnet/netfilter/ipset/Kconfig-45-\nnet/netfilter/ipset/Kconfig:46:config IP_SET_BITMAP_PORT\nnet/netfilter/ipset/Kconfig-47-\ttristate \"bitmap:port set support\"\n--\nnet/netfilter/ipset/Kconfig-54-\nnet/netfilter/ipset/Kconfig:55:config IP_SET_HASH_IP\nnet/netfilter/ipset/Kconfig-56-\ttristate \"hash:ip set support\"\n--\nnet/netfilter/ipset/Kconfig-64-\nnet/netfilter/ipset/Kconfig:65:config IP_SET_HASH_IPMARK\nnet/netfilter/ipset/Kconfig-66-\ttristate \"hash:ip,mark set support\"\n--\nnet/netfilter/ipset/Kconfig-73-\nnet/netfilter/ipset/Kconfig:74:config IP_SET_HASH_IPPORT\nnet/netfilter/ipset/Kconfig-75-\ttristate \"hash:ip,port set support\"\n--\nnet/netfilter/ipset/Kconfig-82-\nnet/netfilter/ipset/Kconfig:83:config IP_SET_HASH_IPPORTIP\nnet/netfilter/ipset/Kconfig-84-\ttristate \"hash:ip,port,ip set support\"\n--\nnet/netfilter/ipset/Kconfig-92-\nnet/netfilter/ipset/Kconfig:93:config IP_SET_HASH_IPPORTNET\nnet/netfilter/ipset/Kconfig-94-\ttristate \"hash:ip,port,net set support\"\n--\nnet/netfilter/ipset/Kconfig-102-\nnet/netfilter/ipset/Kconfig:103:config IP_SET_HASH_IPMAC\nnet/netfilter/ipset/Kconfig-104-\ttristate \"hash:ip,mac set support\"\n--\nnet/netfilter/ipset/Kconfig-111-\nnet/netfilter/ipset/Kconfig:112:config IP_SET_HASH_MAC\nnet/netfilter/ipset/Kconfig-113-\ttristate \"hash:mac set support\"\n--\nnet/netfilter/ipset/Kconfig-120-\nnet/netfilter/ipset/Kconfig:121:config IP_SET_HASH_NETPORTNET\nnet/netfilter/ipset/Kconfig-122-\ttristate \"hash:net,port,net set support\"\n--\nnet/netfilter/ipset/Kconfig-129-\nnet/netfilter/ipset/Kconfig:130:config IP_SET_HASH_NET\nnet/netfilter/ipset/Kconfig-131-\ttristate \"hash:net set support\"\n--\nnet/netfilter/ipset/Kconfig-138-\nnet/netfilter/ipset/Kconfig:139:config IP_SET_HASH_NETNET\nnet/netfilter/ipset/Kconfig-140-\ttristate \"hash:net,net set support\"\n--\nnet/netfilter/ipset/Kconfig-147-\nnet/netfilter/ipset/Kconfig:148:config IP_SET_HASH_NETPORT\nnet/netfilter/ipset/Kconfig-149-\ttristate \"hash:net,port set support\"\n--\nnet/netfilter/ipset/Kconfig-157-\nnet/netfilter/ipset/Kconfig:158:config IP_SET_HASH_NETIFACE\nnet/netfilter/ipset/Kconfig-159-\ttristate \"hash:net,iface set support\"\n--\nnet/netfilter/ipset/Kconfig-167-\nnet/netfilter/ipset/Kconfig:168:config IP_SET_LIST_SET\nnet/netfilter/ipset/Kconfig-169-\ttristate \"list:set set support\"\n"
}

gemini-3.1-pro-preview

							input: 16401
							output: 33
							thoughts: 59

Okay, here's my take on those config considerations, distilled into my internal thought process:

**Kernel Configuration Dependencies**

Alright, looks like `CONFIG_IP_SET` is a hard requirement. Got it. Now, I need to double-check something related to connection tracking, specifically expectations. My instinct is telling me that `CONFIG_NF_CONNTRACK_EXPECT` might be involved. However, I need to be sure. I believe that expectations are a core part of the base `CONFIG_NF_CONNTRACK` module. Now, the question is, is there a distinct configuration option tied directly to the `nf_conntrack_expect.c` module within the kernel source? I need to verify its exact configuration path. It might be part of another configuration or it could be a separate option. I'll need to drill down and see if there are any specific options to be aware of.

{
  "Expression": "nf_conntrack_expect",
  "PathPrefix": "net/netfilter/Makefile"
}

{
  "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 \\\n"
}

gemini-3.1-pro-preview

							input: 16843
							output: 34
							thoughts: 31

Okay, here's my interpretation of those thoughts, presented as a first-person expert summary:

**Connecting the Dots in Netfilter Conntrack**

Alright, so the initial clue points directly to `nf_conntrack-y`. That's a strong indicator. Now, the next logical step is to confirm the presence and configuration of `CONFIG_NF_CT_NETLINK`. This is where the core interaction with userspace happens for `nf_conntrack`. I need to ensure that the necessary netlink interface is enabled. If this configuration option isn't set, then the ability to interact with the conntrack table from userspace via netlink won't be available, and that would cause certain behaviors, specifically in certain network management tools, to fail as expected. This also helps to ensure the expected performance characteristics. I suspect this is the key piece of the puzzle.

{
  "Expression": "config NF_CT_NETLINK",
  "PathPrefix": "net/netfilter/Kconfig"
}

{
  "Output": "net/netfilter/Kconfig=355=config NF_CONNTRACK_TFTP\n--\nnet/netfilter/Kconfig-365-\nnet/netfilter/Kconfig:366:config NF_CT_NETLINK\nnet/netfilter/Kconfig-367-\ttristate 'Connection tracking netlink interface'\n--\nnet/netfilter/Kconfig-372-\nnet/netfilter/Kconfig:373:config NF_CT_NETLINK_TIMEOUT\nnet/netfilter/Kconfig-374-\ttristate  'Connection tracking timeout tuning via Netlink'\n--\nnet/netfilter/Kconfig-384-\nnet/netfilter/Kconfig:385:config NF_CT_NETLINK_HELPER\nnet/netfilter/Kconfig-386-\ttristate 'Connection tracking helpers in user-space via Netlink'\n"
}

gemini-3.1-pro-preview

							input: 17317
							output: 112
							thoughts: 839

**Fuzzing Focus Refinement**

Okay, so I've been taking a look at a few areas within the Netfilter/iptables code, trying to pinpoint good candidates for fuzzing. I've got a fairly comprehensive list of modules to consider: `NF_CONNTRACK`, `NF_CONNTRACK_SIP`, `NF_CT_NETLINK`, `NF_CT_NETLINK_HELPER`, `NETFILTER_NETLINK_QUEUE`, `NF_TABLES`, `NFT_FIB`, `NFT_FIB_NETDEV`, and `IP_SET`. A wide variety.

Now, my initial thought is to dive into functions that handle netlink interactions, packet processing, and those that deal with stateful connections, those areas are ripe with complexity and potential vulnerabilities. I started by looking at `ip_set_core.c` and found `ip_set_dump_do`, since its netlink dump callback, so that's a decent start. Then I looked at `nf_conntrack_expect.c` and `nf_conntrack_netlink.c`, which offered `ctnetlink_alloc_expect` and found some functions in `nf_conntrack_sip.c` like `set_expected_rtp_rtcp`, which could be useful.

`nfnetlink_cthelper.c` and `nfnetlink_queue.c` are also interesting. I saw `nfnl_cthelper_expect_policy`, and `nfqnl_mangle` in `nfnetlink_queue.c` that seems like a good target. It's handling packet manipulation, which is often a source of bugs. The `nfqnl_mangle` symbol is especially promising given its role in altering packets.

The `nft_fib.c` and `nft_fib_netdev.c` code offers `nft_fib_validate` and `nft_fib_netdev_validate`, and they are also looking like potential targets. In `nft_payload.c`, I saw some initializations and evaluations; `nft_payload_set_init` and `nft_payload_set_eval` seem like they should be investigated. I'm also looking into `nft_set_pipapo.c` and found `nft_pipapo_insert` and `pipapo_clone` as candidates too.

So, let's refine this list, focusing on the most promising ones: `ip_set_dump_do`, `ctnetlink_alloc_expect`, `set_expected_rtp_rtcp`, `nfnl_cthelper_expect_policy`, `nfqnl_mangle`, `nft_fib_validate`, `nft_fib_netdev_validate`, `nft_payload_set_init`, `nft_payload_set_eval`, `nft_pipapo_insert`, and `pipapo_clone`. Now it's time to check if these are exported symbols and if they are even suitable for fuzzing in practice.

{
  "Expression": "(ip_set_dump_do|ctnetlink_alloc_expect|set_expected_rtp_rtcp|nfnl_cthelper_expect_policy|nfqnl_mangle|nft_fib_validate|nft_fib_netdev_validate|nft_payload_set_init|nft_payload_set_eval|nft_pipapo_insert|pipapo_clone)",
  "PathPrefix": "net/netfilter/"
}

{
  "Output": "net/netfilter/ipset/ip_set_core.c=1476=static int\nnet/netfilter/ipset/ip_set_core.c:1477:ip_set_dump_done(struct netlink_callback *cb)\nnet/netfilter/ipset/ip_set_core.c-1478-{\n--\nnet/netfilter/ipset/ip_set_core.c=1570=static int\nnet/netfilter/ipset/ip_set_core.c:1571:ip_set_dump_do(struct sk_buff *skb, struct netlink_callback *cb)\nnet/netfilter/ipset/ip_set_core.c-1572-{\n--\nnet/netfilter/ipset/ip_set_core.c=1712=static int ip_set_dump(struct sk_buff *skb, const struct nfnl_info *info,\n--\nnet/netfilter/ipset/ip_set_core.c-1720-\t\t\t.start = ip_set_dump_start,\nnet/netfilter/ipset/ip_set_core.c:1721:\t\t\t.dump = ip_set_dump_do,\nnet/netfilter/ipset/ip_set_core.c:1722:\t\t\t.done = ip_set_dump_done,\nnet/netfilter/ipset/ip_set_core.c-1723-\t\t};\n--\nnet/netfilter/nf_conntrack_netlink.c=2630=static struct nf_conntrack_expect *\nnet/netfilter/nf_conntrack_netlink.c:2631:ctnetlink_alloc_expect(const struct nlattr *const cda[], struct nf_conn *ct,\nnet/netfilter/nf_conntrack_netlink.c-2632-\t\t       const struct nf_conntrack_helper *assign_helper,\n--\nnet/netfilter/nf_conntrack_netlink.c=2856=ctnetlink_glue_attach_expect(const struct nlattr *attr, struct nf_conn *ct,\n--\nnet/netfilter/nf_conntrack_netlink.c-2887-\nnet/netfilter/nf_conntrack_netlink.c:2888:\texp = ctnetlink_alloc_expect((const struct nlattr * const *)cda, ct,\nnet/netfilter/nf_conntrack_netlink.c-2889-\t\t\t\t     assign_helper, \u0026tuple, \u0026mask);\n--\nnet/netfilter/nf_conntrack_netlink.c=3519=static struct nf_conntrack_expect *\nnet/netfilter/nf_conntrack_netlink.c:3520:ctnetlink_alloc_expect(const struct nlattr * const cda[], struct nf_conn *ct,\nnet/netfilter/nf_conntrack_netlink.c-3521-\t\t       const struct nf_conntrack_helper *assign_helper,\n--\nnet/netfilter/nf_conntrack_netlink.c=3591=ctnetlink_create_expect(struct net *net,\n--\nnet/netfilter/nf_conntrack_netlink.c-3622-\trcu_read_lock();\nnet/netfilter/nf_conntrack_netlink.c:3623:\texp = ctnetlink_alloc_expect(cda, ct, NULL, \u0026tuple, \u0026mask);\nnet/netfilter/nf_conntrack_netlink.c-3624-\tif (IS_ERR(exp)) {\n--\nnet/netfilter/nf_conntrack_sip.c=909=static void flush_expectations(struct nf_conn *ct, bool media)\n--\nnet/netfilter/nf_conntrack_sip.c-928-\nnet/netfilter/nf_conntrack_sip.c:929:static int set_expected_rtp_rtcp(struct sk_buff *skb, unsigned int protoff,\nnet/netfilter/nf_conntrack_sip.c-930-\t\t\t\t unsigned int dataoff,\n--\nnet/netfilter/nf_conntrack_sip.c=1116=static int process_sdp(struct sk_buff *skb, unsigned int protoff,\n--\nnet/netfilter/nf_conntrack_sip.c-1198-\nnet/netfilter/nf_conntrack_sip.c:1199:\t\tret = set_expected_rtp_rtcp(skb, protoff, dataoff,\nnet/netfilter/nf_conntrack_sip.c-1200-\t\t\t\t\t    dptr, datalen,\n--\nnet/netfilter/nfnetlink_cthelper.c=145=static int\nnet/netfilter/nfnetlink_cthelper.c:146:nfnl_cthelper_expect_policy(struct nf_conntrack_expect_policy *expect_policy,\nnet/netfilter/nfnetlink_cthelper.c-147-\t\t\t    const struct nlattr *attr)\n--\nnet/netfilter/nfnetlink_cthelper.c=177=static const struct nla_policy\nnet/netfilter/nfnetlink_cthelper.c:178:nfnl_cthelper_expect_policy_set[NFCTH_POLICY_SET_MAX+1] = {\nnet/netfilter/nfnetlink_cthelper.c-179-\t[NFCTH_POLICY_SET_NUM] = NLA_POLICY_MAX(NLA_BE32, NF_CT_MAX_EXPECT_CLASSES),\n--\nnet/netfilter/nfnetlink_cthelper.c=183=nfnl_cthelper_parse_expect_policy(struct nf_conntrack_helper *helper,\n--\nnet/netfilter/nfnetlink_cthelper.c-190-\tret = nla_parse_nested_deprecated(tb, NFCTH_POLICY_SET_MAX, attr,\nnet/netfilter/nfnetlink_cthelper.c:191:\t\t\t\t\t  nfnl_cthelper_expect_policy_set,\nnet/netfilter/nfnetlink_cthelper.c-192-\t\t\t\t\t  NULL);\n--\nnet/netfilter/nfnetlink_cthelper.c-208-\nnet/netfilter/nfnetlink_cthelper.c:209:\t\tret = nfnl_cthelper_expect_policy(\u0026helper-\u003eexpect_policy[i],\nnet/netfilter/nfnetlink_cthelper.c-210-\t\t\t\t\t\t  tb[NFCTH_POLICY_SET+i]);\n--\nnet/netfilter/nfnetlink_cthelper.c=368=static int nfnl_cthelper_update_policy(struct nf_conntrack_helper *helper,\n--\nnet/netfilter/nfnetlink_cthelper.c-375-\terr = nla_parse_nested_deprecated(tb, NFCTH_POLICY_SET_MAX, attr,\nnet/netfilter/nfnetlink_cthelper.c:376:\t\t\t\t\t  nfnl_cthelper_expect_policy_set,\nnet/netfilter/nfnetlink_cthelper.c-377-\t\t\t\t\t  NULL);\n--\nnet/netfilter/nfnetlink_queue.c=1354=static int\nnet/netfilter/nfnetlink_queue.c:1355:nfqnl_mangle(void *data, unsigned int data_len, struct nf_queue_entry *e, int diff)\nnet/netfilter/nfnetlink_queue.c-1356-{\n--\nnet/netfilter/nfnetlink_queue.c=1711=static int nfqnl_recv_verdict(struct sk_buff *skb, const struct nfnl_info *info,\n--\nnet/netfilter/nfnetlink_queue.c-1760-\nnet/netfilter/nfnetlink_queue.c:1761:\t\tif (nfqnl_mangle(nla_data(nfqa[NFQA_PAYLOAD]),\nnet/netfilter/nfnetlink_queue.c-1762-\t\t\t\t payload_len, entry, diff) \u003c 0)\n--\nnet/netfilter/nft_fib.c=27=EXPORT_SYMBOL(nft_fib_policy);\nnet/netfilter/nft_fib.c-28-\nnet/netfilter/nft_fib.c:29:int nft_fib_validate(const struct nft_ctx *ctx, const struct nft_expr *expr)\nnet/netfilter/nft_fib.c-30-{\n--\nnet/netfilter/nft_fib.c-72-}\nnet/netfilter/nft_fib.c:73:EXPORT_SYMBOL_GPL(nft_fib_validate);\nnet/netfilter/nft_fib.c-74-\n--\nnet/netfilter/nft_fib_inet.c=45=static const struct nft_expr_ops nft_fib_inet_ops = {\n--\nnet/netfilter/nft_fib_inet.c-50-\t.dump\t\t= nft_fib_dump,\nnet/netfilter/nft_fib_inet.c:51:\t.validate\t= nft_fib_validate,\nnet/netfilter/nft_fib_inet.c-52-};\n--\nnet/netfilter/nft_fib_netdev.c=21=static void nft_fib_netdev_eval(const struct nft_expr *expr,\n--\nnet/netfilter/nft_fib_netdev.c-52-\nnet/netfilter/nft_fib_netdev.c:53:static int nft_fib_netdev_validate(const struct nft_ctx *ctx,\nnet/netfilter/nft_fib_netdev.c-54-\t\t\t\t   const struct nft_expr *expr)\n--\nnet/netfilter/nft_fib_netdev.c=81=static const struct nft_expr_ops nft_fib_netdev_ops = {\n--\nnet/netfilter/nft_fib_netdev.c-86-\t.dump\t\t= nft_fib_dump,\nnet/netfilter/nft_fib_netdev.c:87:\t.validate\t= nft_fib_netdev_validate,\nnet/netfilter/nft_fib_netdev.c-88-};\n--\nnet/netfilter/nft_payload.c=1059=static bool nft_payload_csum_write_ok(const struct nft_pktinfo *pkt,\n--\nnet/netfilter/nft_payload.c-1079-\nnet/netfilter/nft_payload.c:1080:static void nft_payload_set_eval(const struct nft_expr *expr,\nnet/netfilter/nft_payload.c-1081-\t\t\t\t struct nft_regs *regs,\n--\nnet/netfilter/nft_payload.c-1169-\nnet/netfilter/nft_payload.c:1170:static int nft_payload_set_init(const struct nft_ctx *ctx,\nnet/netfilter/nft_payload.c-1171-\t\t\t\tconst struct nft_expr *expr,\n--\nnet/netfilter/nft_payload.c=1271=static const struct nft_expr_ops nft_payload_set_ops = {\n--\nnet/netfilter/nft_payload.c-1273-\t.size\t\t= NFT_EXPR_SIZE(sizeof(struct nft_payload_set)),\nnet/netfilter/nft_payload.c:1274:\t.eval\t\t= nft_payload_set_eval,\nnet/netfilter/nft_payload.c:1275:\t.init\t\t= nft_payload_set_init,\nnet/netfilter/nft_payload.c-1276-\t.dump\t\t= nft_payload_set_dump,\n--\nnet/netfilter/nft_set_pipapo.c=1243=static bool nft_pipapo_transaction_mutex_held(const struct nft_set *set)\n--\nnet/netfilter/nft_set_pipapo.c-1253-\nnet/netfilter/nft_set_pipapo.c:1254:static struct nft_pipapo_match *pipapo_clone(struct nft_pipapo_match *old);\nnet/netfilter/nft_set_pipapo.c-1255-\n--\nnet/netfilter/nft_set_pipapo.c=1262=static struct nft_pipapo_match *pipapo_maybe_clone(const struct nft_set *set)\n--\nnet/netfilter/nft_set_pipapo.c-1271-\t\t\t\t      nft_pipapo_transaction_mutex_held(set));\nnet/netfilter/nft_set_pipapo.c:1272:\tpriv-\u003eclone = pipapo_clone(m);\nnet/netfilter/nft_set_pipapo.c-1273-\n--\nnet/netfilter/nft_set_pipapo.c-1277-/**\nnet/netfilter/nft_set_pipapo.c:1278: * nft_pipapo_insert() - Validate and insert ranged elements\nnet/netfilter/nft_set_pipapo.c-1279- * @net:\tNetwork namespace\n--\nnet/netfilter/nft_set_pipapo.c-1285- */\nnet/netfilter/nft_set_pipapo.c:1286:static int nft_pipapo_insert(const struct net *net, const struct nft_set *set,\nnet/netfilter/nft_set_pipapo.c-1287-\t\t\t     const struct nft_set_elem *elem,\n--\nnet/netfilter/nft_set_pipapo.c-1425-/**\nnet/netfilter/nft_set_pipapo.c:1426: * pipapo_clone() - Clone matching data to create new working copy\nnet/netfilter/nft_set_pipapo.c-1427- * @old:\tExisting matching data\n--\nnet/netfilter/nft_set_pipapo.c-1430- */\nnet/netfilter/nft_set_pipapo.c:1431:static struct nft_pipapo_match *pipapo_clone(struct nft_pipapo_match *old)\nnet/netfilter/nft_set_pipapo.c-1432-{\n--\nnet/netfilter/nft_set_pipapo.c=1875=static void nft_pipapo_abort(const struct nft_set *set)\n--\nnet/netfilter/nft_set_pipapo.c-1892- * in use for lookups, and not directly inserted into current lookup data. Both\nnet/netfilter/nft_set_pipapo.c:1893: * nft_pipapo_insert() and nft_pipapo_activate() are called once for each\nnet/netfilter/nft_set_pipapo.c-1894- * element, hence we can't purpose either one as a real commit operation.\n--\nnet/netfilter/nft_set_pipapo.c=2418=const struct nft_set_type nft_set_pipapo_type = {\n--\nnet/netfilter/nft_set_pipapo.c-2422-\t\t.lookup\t\t= nft_pipapo_lookup,\nnet/netfilter/nft_set_pipapo.c:2423:\t\t.insert\t\t= nft_pipapo_insert,\nnet/netfilter/nft_set_pipapo.c-2424-\t\t.activate\t= nft_pipapo_activate,\n--\nnet/netfilter/nft_set_pipapo.c=2443=const struct nft_set_type nft_set_pipapo_avx2_type = {\n--\nnet/netfilter/nft_set_pipapo.c-2447-\t\t.lookup\t\t= nft_pipapo_avx2_lookup,\nnet/netfilter/nft_set_pipapo.c:2448:\t\t.insert\t\t= nft_pipapo_insert,\nnet/netfilter/nft_set_pipapo.c-2449-\t\t.activate\t= nft_pipapo_activate,\n--\nnet/netfilter/nft_set_pipapo.h=128=struct nft_pipapo_scratch {\n--\nnet/netfilter/nft_set_pipapo.h-133-\nnet/netfilter/nft_set_pipapo.h:134:enum nft_pipapo_clone_state {\nnet/netfilter/nft_set_pipapo.h-135-\tNFT_PIPAPO_CLONE_NEW,\n--\nnet/netfilter/nft_set_pipapo.h=149=struct nft_pipapo_match {\nnet/netfilter/nft_set_pipapo.h-150-\tu8 field_count;\nnet/netfilter/nft_set_pipapo.h:151:\tenum nft_pipapo_clone_state state:8;\nnet/netfilter/nft_set_pipapo.h-152-\tunsigned int bsize_max;\n"
}

gemini-3.1-pro-preview

							input: 23085
							output: 32
							thoughts: 963

**Refining the Relevant Symbols and Configurations**

Okay, let's break this down. My initial focus was on identifying the key function symbols impacted by these changes. I started with a broader list: `ip_set_dump_do`, `ctnetlink_alloc_expect`, `set_expected_rtp_rtcp`, `nfnl_cthelper_expect_policy`, `nfqnl_mangle`, `nft_fib_validate`, `nft_fib_netdev_validate`, `nft_payload_set_init`, `nft_payload_set_eval`, `nft_pipapo_insert`, and `pipapo_clone`.

Then, I started refining this list. I realized that several of those are static and used within other static functions. So, I need to focus on the ones with broader implications or that represent the public interface. That led me to consider a second set: `ip_set_dump_done`, `nf_ct_expect_alloc`, `nf_ct_expect_init`, `nfqnl_validate_write`, and expanded it again. I know I have to cover the core changes.

Now, I'm thinking of a concise, representative list that avoids the most hot-path functions, but captures the essence of the changes. The final list includes: `ip_set_dump_done`, `ip_set_dump_do`, `ctnetlink_alloc_expect`, `set_expected_rtp_rtcp`, `nfnl_cthelper_expect_policy`, `nfqnl_mangle`, `nft_fib_validate`, `nft_fib_netdev_validate`, `nft_payload_set_init`, `nft_payload_set_eval`, and `nft_pipapo_insert`.

Next, I need to analyze the relevant configurations. The initial list I had was: `NF_CONNTRACK`, `NF_CONNTRACK_SIP`, `NF_CT_NETLINK`, `NF_CT_NETLINK_HELPER`, `NETFILTER_NETLINK_QUEUE`, `NF_TABLES`, `NFT_FIB`, `NFT_FIB_NETDEV`, and `IP_SET`.

I have to double-check that they are the right ones. I checked `NF_CONNTRACK_EXPECT` and the source files included. That made me consider how `NFT_FIB_NETDEV` related to `NF_TABLES`. And I checked `NFT_PIPAPO` too. I am satisfied the configurations listed are the right set of relevant configurations.

{
  "Expression": "config NF_CONNTRACK",
  "PathPrefix": "net/netfilter/Kconfig"
}

{
  "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"
}

gemini-3.1-pro-preview

							input: 25923
							output: 32
							thoughts: 14

Okay, here's my take on those thoughts, tailored for an expert audience:

**Initial Assessment and Deep Dive**

Alright, initial impression: things seem to be in order. The overall architecture and design are presenting well. Before getting too far ahead, I'm thinking let's pivot to the nitty-gritty and focus our attention specifically on the `NF_TABLES` implementation. That's the core of the system, that's where the real logic lives. We'll examine the table configurations, chain definitions, rulesets, and how everything is connected. That level of detail is critical for catching potential subtle issues, optimizations, or unexpected behavior. No assumptions; it's time to dig in.

{
  "Expression": "config NF_TABLES",
  "PathPrefix": "net/netfilter/Kconfig"
}

{
  "Output": "net/netfilter/Kconfig=453=endif # NF_CONNTRACK\nnet/netfilter/Kconfig-454-\nnet/netfilter/Kconfig:455:config NF_TABLES\nnet/netfilter/Kconfig-456-\tselect NETFILTER_NETLINK\n--\nnet/netfilter/Kconfig=471=if NF_TABLES\nnet/netfilter/Kconfig:472:config NF_TABLES_INET\nnet/netfilter/Kconfig-473-\tdepends on IPV6\n--\nnet/netfilter/Kconfig-479-\nnet/netfilter/Kconfig:480:config NF_TABLES_NETDEV\nnet/netfilter/Kconfig-481-\tbool \"Netfilter nf_tables netdev tables support\"\n"
}

gemini-3.1-pro-preview

							input: 26323
							output: 35
							thoughts: 91

**Checking Dependencies for Network Filtering Features**

Okay, I need to make a quick addition to ensure broad compatibility. I should proactively include `NF_TABLES_NETDEV` and `NF_TABLES_INET` in my configuration just to be safe. It's possible that `nft_fib_netdev.c` and `nft_fib_inet.c` might have dependencies on them, and I don't want to run into any unexpected issues later. Now, hold on, I recall that `nft_fib_netdev.c` specifically relies on `NFT_FIB_NETDEV`. Alright, so that's the key. Let me immediately check the dependencies for `NFT_FIB_NETDEV` to confirm everything is in order and that I'm covering all the bases. I need to make sure this is all set up correctly before I continue.

{
  "Expression": "config NFT_FIB_NETDEV",
  "PathPrefix": "net/netfilter/Kconfig"
}

{
  "Output": "net/netfilter/Kconfig=674=config NFT_FWD_NETDEV\n--\nnet/netfilter/Kconfig-679-\nnet/netfilter/Kconfig:680:config NFT_FIB_NETDEV\nnet/netfilter/Kconfig-681-\tdepends on NFT_FIB_IPV4\n"
}

gemini-3.1-pro-preview

							input: 26726
							output: 38
							thoughts: 26

Here's my take on those thoughts, assuming I'm an expert:

**Investigating the Need for `NFT_FIB_IPV4`**

Okay, so we're talking about `NFT_FIB_IPV4`. That's a key element in the `nftables` framework related to IPV4 forwarding information base (FIB) lookups. Essentially, it deals with routing decisions. The fact that it's even coming up suggests we're dealing with a situation where traditional routing tables are either inadequate or we're looking for something more sophisticated. My initial thought is that we're either building some kind of custom routing logic, implementing policy-based routing, or perhaps trying to optimize performance in a highly specific network scenario. The inclusion of the "FIB" is a red flag in the best way, and suggests we're working with something relatively low-level. I'll need to dig into the context to understand *why* this specific module is required, but first, I'm going to take a closer look at `NFT_FIB_IPV4` to confirm exactly what functionality it provides and what design decisions were made, so I can start to understand its function in the wider context.

{
  "Expression": "config NFT_FIB_IPV4",
  "PathPrefix": "net/ipv4/netfilter/Kconfig"
}

{
  "Output": "net/ipv4/netfilter/Kconfig=47=config NFT_DUP_IPV4\n--\nnet/ipv4/netfilter/Kconfig-53-\nnet/ipv4/netfilter/Kconfig:54:config NFT_FIB_IPV4\nnet/ipv4/netfilter/Kconfig-55-\tselect NFT_FIB\n"
}

gemini-3.1-pro-preview

							input: 27142
							output: 38
							thoughts: 13

Okay, here's my attempt at summarizing that thought process, keeping in mind I'm speaking to a fellow expert:

**Investigating `NFT_FIB_IPV6`**

Alright, time to dive in. My initial thought is, "Let's check `NFT_FIB_IPV6`." Given the context, this likely means I'm troubleshooting, analyzing, or perhaps optimizing a network setup that involves IPv6 routing and forwarding tables. The specific naming convention immediately tells me we're likely using `nftables` (or the older `iptables` with some compatibility layers). I'm probably looking at a potential performance bottleneck, a misconfigured rule, or maybe trying to understand the current state of a complex firewall/routing setup. The fact that I'm specifically targeting the IPv6 FIB indicates a clear focus on the IPv6 portion of the network architecture. Let's get to it.

{
  "Expression": "config NFT_FIB_IPV6",
  "PathPrefix": "net/ipv6/netfilter/Kconfig"
}

{
  "Output": "net/ipv6/netfilter/Kconfig=43=config NFT_DUP_IPV6\n--\nnet/ipv6/netfilter/Kconfig-49-\nnet/ipv6/netfilter/Kconfig:50:config NFT_FIB_IPV6\nnet/ipv6/netfilter/Kconfig-51-\ttristate \"nf_tables fib / ipv6 route lookup support\"\n"
}

gemini-3.1-pro-preview

							input: 27489
							output: 358
							thoughts: 498

**My Netfilter Patch Review**

Okay, so we're adding `NFT_FIB_IPV4` and `NFT_FIB_IPV6`. Makes sense. Now, let's summarize the configuration items required to make sure we've got everything in order: `NF_CONNTRACK`, `NF_CONNTRACK_SIP`, `NF_CT_NETLINK`, `NF_CT_NETLINK_HELPER`, `NETFILTER_NETLINK_QUEUE`, `NF_TABLES`, `NFT_FIB_IPV4`, `NFT_FIB_IPV6`, `NFT_FIB_NETDEV`, and `IP_SET`.

Let's do a quick double-check on `NF_TABLES_NETDEV` and `NF_TABLES_INET` since they can sometimes be tricky. Ah, right, `NFT_FIB_NETDEV` depends on `NFT_FIB_IPV4`, and `NFT_FIB_INET` depends on `NF_TABLES_INET`. To be absolutely sure, I'm going to include both `NF_TABLES_NETDEV` and `NF_TABLES_INET`. Better safe than sorry when dealing with these core components.

Now, let's get a look at the key symbols involved. We have `ip_set_dump_do`, `ip_set_dump_done`, `ctnetlink_alloc_expect`, `set_expected_rtp_rtcp`, `nfnl_cthelper_expect_policy`, `nfqnl_mangle`, `nft_fib_validate`, `nft_fib_netdev_validate`, `nft_payload_set_init`, `nft_payload_set_eval`, and `nft_pipapo_insert`. Looks like this is a solid list covering the areas where changes were directly implemented or where the logic has been updated, right where it matters.

From a functional standpoint, this patch series introduces some important, quite deep changes to Netfilter. We have new validation steps for payload writes and IP/IPv6 headers before mangling, that's crucial for security. Then there's the fix for the SIP conntrack expectation bug, a state tracking addition for pipapo set clones that should help handle aborts more robustly, and the modifications to conntrack expectation allocation and initialization. All of these affect core Netfilter logic. We're talking Netlink queue, nftables payload mangling, and pipapo sets, and that's all stuff that userspace has direct access to, so this needs to be rigorously tested. We absolutely need to make sure we're not introducing regressions or vulnerabilities here. We have to fuzz it heavily.

Right, I'm going to run the `set-results` tool now to see how the change impacts the system.

{
  "EnableConfigs": [
    "NF_CONNTRACK",
    "NF_CONNTRACK_SIP",
    "NF_CT_NETLINK",
    "NF_CT_NETLINK_HELPER",
    "NETFILTER_NETLINK_QUEUE",
    "NF_TABLES",
    "NF_TABLES_INET",
    "NF_TABLES_NETDEV",
    "NFT_FIB_IPV4",
    "NFT_FIB_IPV6",
    "NFT_FIB_NETDEV",
    "IP_SET"
  ],
  "FocusSymbols": [
    "ip_set_dump_do",
    "ip_set_dump_done",
    "ctnetlink_alloc_expect",
    "set_expected_rtp_rtcp",
    "nfnl_cthelper_expect_policy",
    "nfqnl_mangle",
    "nft_fib_validate",
    "nft_fib_netdev_validate",
    "nft_payload_set_init",
    "nft_payload_set_eval",
    "nft_pipapo_insert"
  ],
  "Reasoning": "The patch series introduces significant functional changes to the netfilter subsystem. It adds validation for payload writes and IP/IPv6 headers before mangling, fixes a bug in SIP conntrack expectation, adds state tracking for pipapo set clones to properly handle aborts, and modifies conntrack expectation allocation and initialization. These changes affect core netfilter logic, netlink queue, nftables payload mangling, and pipapo sets, which are all reachable from userspace and should be heavily fuzzed to ensure no regressions or vulnerabilities are introduced.",
  "WorthFuzzing": true
}

{
  "EnableConfigs": [
    "NF_CONNTRACK",
    "NF_CONNTRACK_SIP",
    "NF_CT_NETLINK",
    "NF_CT_NETLINK_HELPER",
    "NETFILTER_NETLINK_QUEUE",
    "NF_TABLES",
    "NF_TABLES_INET",
    "NF_TABLES_NETDEV",
    "NFT_FIB_IPV4",
    "NFT_FIB_IPV6",
    "NFT_FIB_NETDEV",
    "IP_SET"
  ],
  "FocusSymbols": [
    "ip_set_dump_do",
    "ip_set_dump_done",
    "ctnetlink_alloc_expect",
    "set_expected_rtp_rtcp",
    "nfnl_cthelper_expect_policy",
    "nfqnl_mangle",
    "nft_fib_validate",
    "nft_fib_netdev_validate",
    "nft_payload_set_init",
    "nft_payload_set_eval",
    "nft_pipapo_insert"
  ],
  "Reasoning": "The patch series introduces significant functional changes to the netfilter subsystem. It adds validation for payload writes and IP/IPv6 headers before mangling, fixes a bug in SIP conntrack expectation, adds state tracking for pipapo set clones to properly handle aborts, and modifies conntrack expectation allocation and initialization. These changes affect core netfilter logic, netlink queue, nftables payload mangling, and pipapo sets, which are all reachable from userspace and should be heavily fuzzed to ensure no regressions or vulnerabilities are introduced.",
  "WorthFuzzing": true
}

LLM Calls Summary:
Total Calls	Total Tokens	Avg Tokens	Total Duration (Seconds)	Avg Duration (Seconds)

Tool Calls Summary:
Total Calls	Total Duration (Seconds)	Avg Duration (Seconds)