AI Trajectory

null

{
  "EnableConfigs": [
    "VXLAN",
    "NET_IPGRE",
    "IPV6_GRE"
  ],
  "FocusSymbols": [
    "vxlan_rcv",
    "__iptunnel_pull_header"
  ],
  "Reasoning": "The patch modifies `vxlan_rcv` and `__iptunnel_pull_header` to unset the transport header of the `sk_buff`. This is a functional change in the networking stack affecting VXLAN and IP tunnels (like GRE). Fuzzing should focus on these receive paths to ensure the transport header is correctly unset and doesn't cause regressions in subsequent packet processing.",
  "WorthFuzzing": true
}

null

{
  "PatchDiff": "commit 5eb7ba3352b6103a5933f760e05373ded11465fa\nAuthor: syz-cluster \u003ctriage@syzkaller.com\u003e\nDate:   Wed Jun 24 10:17:46 2026 +0000\n\n    syz-cluster: applied patch under review\n\ndiff --git a/drivers/net/vxlan/vxlan_core.c b/drivers/net/vxlan/vxlan_core.c\nindex 67c367cc566233..49318ad8164a2f 100644\n--- a/drivers/net/vxlan/vxlan_core.c\n+++ b/drivers/net/vxlan/vxlan_core.c\n@@ -1799,6 +1799,7 @@ static int vxlan_rcv(struct sock *sk, struct sk_buff *skb)\n \n \tdev_dstats_rx_add(vxlan-\u003edev, skb-\u003elen);\n \tvxlan_vnifilter_count(vxlan, vni, vninode, VXLAN_VNI_STATS_RX, skb-\u003elen);\n+\tskb_unset_transport_header(skb);\n \tgro_cells_receive(\u0026vxlan-\u003egro_cells, skb);\n \n \trcu_read_unlock();\ndiff --git a/include/linux/skbuff.h b/include/linux/skbuff.h\nindex 115db8c44db213..e8305a0fd3857a 100644\n--- a/include/linux/skbuff.h\n+++ b/include/linux/skbuff.h\n@@ -3084,6 +3084,11 @@ static inline bool skb_transport_header_was_set(const struct sk_buff *skb)\n \treturn skb-\u003etransport_header != (typeof(skb-\u003etransport_header))~0U;\n }\n \n+static inline void skb_unset_transport_header(struct sk_buff *skb)\n+{\n+\tskb-\u003etransport_header = (typeof(skb-\u003etransport_header))~0U;\n+}\n+\n static inline unsigned char *skb_transport_header(const struct sk_buff *skb)\n {\n \tDEBUG_NET_WARN_ON_ONCE(!skb_transport_header_was_set(skb));\ndiff --git a/net/ipv4/ip_tunnel_core.c b/net/ipv4/ip_tunnel_core.c\nindex d3c677e9bff208..59192f58da2e3a 100644\n--- a/net/ipv4/ip_tunnel_core.c\n+++ b/net/ipv4/ip_tunnel_core.c\n@@ -134,6 +134,7 @@ int __iptunnel_pull_header(struct sk_buff *skb, int hdr_len,\n \t__vlan_hwaccel_clear_tag(skb);\n \tskb_set_queue_mapping(skb, 0);\n \tskb_scrub_packet(skb, xnet);\n+\tskb_unset_transport_header(skb);\n \n \treturn iptunnel_pull_offloads(skb);\n }\n"
}

gemini-3.1-pro-preview

null

{
  "EnableConfigs": [
    "VXLAN",
    "NET_IPGRE",
    "IPV6_GRE"
  ],
  "FocusSymbols": [
    "vxlan_rcv",
    "__iptunnel_pull_header"
  ],
  "Reasoning": "The patch modifies `vxlan_rcv` and `__iptunnel_pull_header` to unset the transport header of the `sk_buff`. This is a functional change in the networking stack affecting VXLAN and IP tunnels (like GRE). Fuzzing should focus on these receive paths to ensure the transport header is correctly unset and doesn't cause regressions in subsequent packet processing.",
  "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 5eb7ba3352b6103a5933f760e05373ded11465fa
Author: syz-cluster <triage@syzkaller.com>
Date:   Wed Jun 24 10:17:46 2026 +0000

    syz-cluster: applied patch under review

diff --git a/drivers/net/vxlan/vxlan_core.c b/drivers/net/vxlan/vxlan_core.c
index 67c367cc566233..49318ad8164a2f 100644
--- a/drivers/net/vxlan/vxlan_core.c
+++ b/drivers/net/vxlan/vxlan_core.c
@@ -1799,6 +1799,7 @@ static int vxlan_rcv(struct sock *sk, struct sk_buff *skb)
 
 	dev_dstats_rx_add(vxlan->dev, skb->len);
 	vxlan_vnifilter_count(vxlan, vni, vninode, VXLAN_VNI_STATS_RX, skb->len);
+	skb_unset_transport_header(skb);
 	gro_cells_receive(&vxlan->gro_cells, skb);
 
 	rcu_read_unlock();
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 115db8c44db213..e8305a0fd3857a 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -3084,6 +3084,11 @@ static inline bool skb_transport_header_was_set(const struct sk_buff *skb)
 	return skb->transport_header != (typeof(skb->transport_header))~0U;
 }
 
+static inline void skb_unset_transport_header(struct sk_buff *skb)
+{
+	skb->transport_header = (typeof(skb->transport_header))~0U;
+}
+
 static inline unsigned char *skb_transport_header(const struct sk_buff *skb)
 {
 	DEBUG_NET_WARN_ON_ONCE(!skb_transport_header_was_set(skb));
diff --git a/net/ipv4/ip_tunnel_core.c b/net/ipv4/ip_tunnel_core.c
index d3c677e9bff208..59192f58da2e3a 100644
--- a/net/ipv4/ip_tunnel_core.c
+++ b/net/ipv4/ip_tunnel_core.c
@@ -134,6 +134,7 @@ int __iptunnel_pull_header(struct sk_buff *skb, int hdr_len,
 	__vlan_hwaccel_clear_tag(skb);
 	skb_set_queue_mapping(skb, 0);
 	skb_scrub_packet(skb, xnet);
+	skb_unset_transport_header(skb);
 
 	return iptunnel_pull_offloads(skb);
 }

gemini-3.1-pro-preview

null

null

							input: 2355
							output: 32
							thoughts: 223
						

**Fuzzing the VXLAN and IP Tunneling Changes**

Okay, so we have this patch hitting the networking stack. It's touching `vxlan_core.c`, `skbuff.h`, and `ip_tunnel_core.c`. The core of the change is adding `skb_unset_transport_header(skb)` in `vxlan_rcv` and `__iptunnel_pull_header`, and defining it in `skbuff.h`. This is definitely a functional change – impacting VXLAN and the IP tunnel code, which is a prime target for fuzzing.

My immediate thought is to zero in on relevant configurations and focus symbols. The key functions to watch are `vxlan_rcv` and `__iptunnel_pull_header` as they're the direct targets of the patch.

Now, which configs are crucial? Obviously, we'll need `VXLAN` enabled. Also, a config like `NET_IP_TUNNEL` or something along those lines is likely required for the IP tunnel functionality. Time to dive into the Kconfig files: `drivers/net/vxlan/Kconfig` and `net/ipv4/Kconfig` to pin down the exact config options needed. Let's see what builds we need to ensure this code is actually included and exercised during the fuzzing process.

no matches

{
  "Expression": "config VXLAN",
  "PathPrefix": "drivers/net/vxlan/Kconfig"
}

{
  "error": "no matches"
}

gemini-3.1-pro-preview

null

null

							input: 2910
							output: 24
							thoughts: 39
						

Here's my thought process, as if I were considering this issue:

**Navigating Kconfig Dependencies**

Okay, so I'm thinking about this `drivers/net/vxlan/Kconfig` file... the nagging feeling is that it *might* not actually be there. I've seen situations like this before, where the VXLAN configuration is handled differently, perhaps nested within a broader network configuration. So, rather than assume, I need to verify its existence and structure. My first instinct is to check two likely locations. Either it’s directly within the general `drivers/net/Kconfig` file, or perhaps the directory `drivers/net/vxlan/` exists, and the Kconfig might reside within that structure, perhaps named something slightly different. Let's start digging into those locations to confirm its specific placement and how the VXLAN configuration is intended to be managed.

{
  "Dir": "drivers/net/vxlan"
}

{
  "Files": [
    "vxlan_core.c",
    "vxlan_mdb.c",
    "vxlan_multicast.c",
    "vxlan_private.h",
    "vxlan_vnifilter.c"
  ],
  "Subdirs": null
}

gemini-3.1-pro-preview

null

null

							input: 3221
							output: 27
							thoughts: 50
						

Okay, here's my interpretation of that thought process, tailored for an expert audience:

**VXLAN Kernel Module Location Inquiry**

Right, so I'm digging into this kernel module structure, and it seems like the `drivers/net/vxlan/` directory lacks a dedicated `Kconfig` file. Hmm, that's not the standard approach, usually, I'd expect one there for configuration options. Therefore, I need to figure out where the module's build configuration is managed. My immediate approach is to check the related Makefiles, specifically `drivers/net/vxlan/Makefile` and then `drivers/net/Makefile` to see how `vxlan_core.o` is being included. I'm going to grep for the object file name to pinpoint the relevant build rules. This should point me to the correct configuration location or any conditional compile directives.

{
  "Expression": "vxlan",
  "PathPrefix": "drivers/net/Makefile"
}

{
  "Output": "drivers/net/Makefile=35=obj-$(CONFIG_VIRTIO_NET) += virtio_net.o\ndrivers/net/Makefile:36:obj-$(CONFIG_VXLAN) += vxlan/\ndrivers/net/Makefile-37-obj-$(CONFIG_GENEVE) += geneve.o\n"
}

gemini-3.1-pro-preview

null

null

							input: 3568
							output: 31
							thoughts: 42
						

Okay, here's my take on those thoughts, framed as my own:

**Analyzing VXLAN Configuration and Tunnel Header Handling**

Alright, let's see. The focus here seems to be on `CONFIG_VXLAN` – that's the configuration option driving this whole VXLAN discussion. But my mind immediately jumps to a crucial function: `__iptunnel_pull_header`. Where does *that* come into play? It's right there in `net/ipv4/ip_tunnel_core.c`. So, we need to understand how this function is working in relation to the VXLAN configuration. Is it the key piece for extracting the inner header? I need to review that code path in relation to the configuration to fully understand the flow. I need to keep in mind, and verify if it's the core. It almost certainly is, but I can't assume. Let's delve deeper into how these elements interact.

{
  "Expression": "ip_tunnel_core",
  "PathPrefix": "net/ipv4/Makefile"
}

{
  "Output": "net/ipv4/Makefile=6=obj-y     := route.o inetpeer.o protocol.o \\\n--\nnet/ipv4/Makefile-15-\t     fib_frontend.o fib_semantics.o fib_trie.o fib_notifier.o \\\nnet/ipv4/Makefile:16:\t     inet_fragment.o ping.o ip_tunnel_core.o gre_offload.o \\\nnet/ipv4/Makefile-17-\t     metrics.o netlink.o nexthop.o udp_tunnel_stub.o\n"
}

gemini-3.1-pro-preview

null

null

							input: 3982
							output: 27
							thoughts: 87
						

Here's my thought process, as if I were analyzing this code:

**Analyzing the ip_tunnel_core.o Build Process**

Okay, so `ip_tunnel_core.o` is being built unconditionally, as indicated by `obj-y`. But wait a minute, in the `net/ipv4/Makefile`, `obj-y` implies it depends on `CONFIG_INET`. I need to confirm this dependency; it's always good to be thorough.

Right, so what other configurations could be influencing this? Let me check quickly... Ah, there's `CONFIG_VXLAN`, of course! That's a primary contender, considering the nature of tunnels. I'll make a mental note of this.

Now, let's switch gears a bit. I need to understand how `__iptunnel_pull_header` is used in this context. Let me trace the callers of that function; understanding the caller context is key to understanding the overall structure. This will likely shed some light on where this particular module is being used.

{
  "Expression": "__iptunnel_pull_header",
  "PathPrefix": ""
}

{
  "Output": "drivers/net/vxlan/vxlan_core.c=1646=static int vxlan_rcv(struct sock *sk, struct sk_buff *skb)\n--\ndrivers/net/vxlan/vxlan_core.c-1711-\ndrivers/net/vxlan/vxlan_core.c:1712:\tif (__iptunnel_pull_header(skb, VXLAN_HLEN, protocol, raw_proto,\ndrivers/net/vxlan/vxlan_core.c-1713-\t\t\t\t   !net_eq(vxlan-\u003enet, dev_net(vxlan-\u003edev)))) {\n--\ninclude/net/ip_tunnels.h=607=static inline u8 ip_tunnel_ecn_encap(u8 tos, const struct iphdr *iph,\n--\ninclude/net/ip_tunnels.h-614-\ninclude/net/ip_tunnels.h:615:int __iptunnel_pull_header(struct sk_buff *skb, int hdr_len,\ninclude/net/ip_tunnels.h-616-\t\t\t   __be16 inner_proto, bool raw_proto, bool xnet);\n--\ninclude/net/ip_tunnels.h=618=static inline int iptunnel_pull_header(struct sk_buff *skb, int hdr_len,\n--\ninclude/net/ip_tunnels.h-620-{\ninclude/net/ip_tunnels.h:621:\treturn __iptunnel_pull_header(skb, hdr_len, inner_proto, false, xnet);\ninclude/net/ip_tunnels.h-622-}\n--\ninclude/net/udp.h=632=static inline void udp_post_segment_fix_csum(struct sk_buff *skb)\n--\ninclude/net/udp.h-638-\t * can reach an UDP socket with CHECKSUM_NONE, because\ninclude/net/udp.h:639:\t * __iptunnel_pull_header() converts CHECKSUM_PARTIAL into NONE.\ninclude/net/udp.h-640-\t * SKB_GSO_UDP_L4 or SKB_GSO_FRAGLIST packets with no UDP tunnel will\n--\nnet/ipv4/ip_gre.c=267=static int erspan_rcv(struct sk_buff *skb, struct tnl_ptk_info *tpi,\n--\nnet/ipv4/ip_gre.c-311-\nnet/ipv4/ip_gre.c:312:\t\tif (__iptunnel_pull_header(skb,\nnet/ipv4/ip_gre.c-313-\t\t\t\t\t   len,\n--\nnet/ipv4/ip_gre.c-336-\nnet/ipv4/ip_gre.c:337:\t\t\t/* skb can be uncloned in __iptunnel_pull_header, so\nnet/ipv4/ip_gre.c-338-\t\t\t * old pkt_md is no longer valid and we need to reset\n--\nnet/ipv4/ip_gre.c=366=static int __ipgre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi,\n--\nnet/ipv4/ip_gre.c-379-\nnet/ipv4/ip_gre.c:380:\t\tif (__iptunnel_pull_header(skb, hdr_len, tpi-\u003eproto,\nnet/ipv4/ip_gre.c-381-\t\t\t\t\t   raw_proto, false) \u003c 0)\n--\nnet/ipv4/ip_tunnel_core.c=107=EXPORT_SYMBOL_GPL(iptunnel_xmit);\nnet/ipv4/ip_tunnel_core.c-108-\nnet/ipv4/ip_tunnel_core.c:109:int __iptunnel_pull_header(struct sk_buff *skb, int hdr_len,\nnet/ipv4/ip_tunnel_core.c-110-\t\t\t   __be16 inner_proto, bool raw_proto, bool xnet)\n--\nnet/ipv4/ip_tunnel_core.c-140-}\nnet/ipv4/ip_tunnel_core.c:141:EXPORT_SYMBOL_GPL(__iptunnel_pull_header);\nnet/ipv4/ip_tunnel_core.c-142-\n--\nnet/ipv6/ip6_gre.c=490=static int ip6erspan_rcv(struct sk_buff *skb,\n--\nnet/ipv6/ip6_gre.c-515-\nnet/ipv6/ip6_gre.c:516:\t\tif (__iptunnel_pull_header(skb, len,\nnet/ipv6/ip6_gre.c-517-\t\t\t\t\t   htons(ETH_P_TEB),\n--\nnet/ipv6/ip6_gre.c-541-\nnet/ipv6/ip6_gre.c:542:\t\t\t/* skb can be uncloned in __iptunnel_pull_header, so\nnet/ipv6/ip6_gre.c-543-\t\t\t * old pkt_md is no longer valid and we need to reset\n"
}

gemini-3.1-pro-preview

null

null

							input: 5602
							output: 39
							thoughts: 257
						

**My Analysis of the Code Modification**

Okay, so this patch is touching `__iptunnel_pull_header` and `vxlan_rcv`. Since `__iptunnel_pull_header` is used by a few different functions like `vxlan_rcv`, `erspan_rcv`, `__ipgre_rcv`, and `ip6erspan_rcv`, focusing on `vxlan_rcv` and `__iptunnel_pull_header` seems like the right approach.

I need to figure out what configurations are relevant to this change. Naturally, `CONFIG_VXLAN` is the primary one, given that it directly impacts `vxlan_rcv`. But, for complete coverage, especially when considering `__iptunnel_pull_header`, I should also look at `CONFIG_NET_IPGRE` and `CONFIG_IPV6_GRE`, since they use the same function through GRE. Let's make a note to enable those in any testing I do.

Hold on, I just remembered something. `__iptunnel_pull_header` actually resides in `net/ipv4/ip_tunnel_core.c`, and that code is built unconditionally as long as `CONFIG_INET` is enabled. So, while `CONFIG_NET_IPGRE` and `CONFIG_IPV6_GRE` are good to verify the other use cases, `CONFIG_VXLAN` is the critical configuration to focus on for `vxlan_rcv`.

Now I need to dive into `net/ipv4/ip_tunnel_core.c` and specifically examine `__iptunnel_pull_header` to understand the actual changes and their implications.

{
  "Expression": "__iptunnel_pull_header",
  "PathPrefix": "net/ipv4/ip_tunnel_core.c"
}

{
  "Output": "net/ipv4/ip_tunnel_core.c=107=EXPORT_SYMBOL_GPL(iptunnel_xmit);\nnet/ipv4/ip_tunnel_core.c-108-\nnet/ipv4/ip_tunnel_core.c:109:int __iptunnel_pull_header(struct sk_buff *skb, int hdr_len,\nnet/ipv4/ip_tunnel_core.c-110-\t\t\t   __be16 inner_proto, bool raw_proto, bool xnet)\n--\nnet/ipv4/ip_tunnel_core.c-140-}\nnet/ipv4/ip_tunnel_core.c:141:EXPORT_SYMBOL_GPL(__iptunnel_pull_header);\nnet/ipv4/ip_tunnel_core.c-142-\n"
}

gemini-3.1-pro-preview

null

null

							input: 6462
							output: 32
							thoughts: 123
						

**Examining the Kernel's IP Tunneling Logic**

Okay, hold on a second... I see that `__iptunnel_pull_header` is actually exported. That's a key piece of information. This means it's potentially accessible outside the module in which it's defined.

Right, let's quickly check what `skb_unset_transport_header` does, to see the effect of invoking this function. Ah, it sets `skb->transport_header = ~0U`. Okay, so that's a *definite* change to the packet's metadata; this is a functional modification and not just a read.

My focus now is on a few key symbols: `vxlan_rcv` and especially `__iptunnel_pull_header`. I need to understand how these relate, given this exposed function. I'm also mindful of the configurations at play here: `VXLAN`, `NET_IPGRE`, and `IPV6_GRE`.

Now, before I proceed further, I should really verify how `NET_IPGRE` and `IPV6_GRE` are used in relation to the other configurations. That's the logical next step.

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

{
  "Output": "net/ipv4/Kconfig=162=config NET_IPIP\n--\nnet/ipv4/Kconfig-179-\nnet/ipv4/Kconfig:180:config NET_IPGRE_DEMUX\nnet/ipv4/Kconfig-181-\ttristate \"IP: GRE demultiplexer\"\n--\nnet/ipv4/Kconfig=186=config NET_IP_TUNNEL\n--\nnet/ipv4/Kconfig-191-\nnet/ipv4/Kconfig:192:config NET_IPGRE\nnet/ipv4/Kconfig-193-\ttristate \"IP: GRE tunnels over IP\"\n--\nnet/ipv4/Kconfig-206-\nnet/ipv4/Kconfig:207:config NET_IPGRE_BROADCAST\nnet/ipv4/Kconfig-208-\tbool \"IP: broadcast GRE over IP\"\n"
}

gemini-3.1-pro-preview

null

null

							input: 7101
							output: 33
							thoughts: 10
						

Okay, here's my interpretation of that thought process, tailored for an expert audience, and presented as if it were my own internal monologue:

**Affirmation and Directness**

Right, *NET_IPGRE*... yes, it absolutely exists. No need to belabor the obvious. It's a standard, a known quantity. We're not debating its existence; the question is what it implies. Let's move on.

{
  "Expression": "config IPV6_GRE",
  "PathPrefix": "net/ipv6/Kconfig"
}

{
  "Output": "net/ipv6/Kconfig=199=config IPV6_TUNNEL\n--\nnet/ipv6/Kconfig-209-\nnet/ipv6/Kconfig:210:config IPV6_GRE\nnet/ipv6/Kconfig-211-\ttristate \"IPv6: GRE tunnel\"\n"
}

gemini-3.1-pro-preview

null

null

							input: 7328
							output: 145
							thoughts: 188
						

**My Assessment of the Configuration Changes**

Okay, so I've confirmed that `IPV6_GRE` is indeed a configuration option, good to know. Now, let's nail down precisely which configurations are implicated here. Based on what I'm seeing, we're looking at `VXLAN`, `NET_IPGRE`, and `IPV6_GRE`.

The core of the matter is the modification to `vxlan_rcv` and `__iptunnel_pull_header`. Essentially, the patch is changing how the networking stack handles the transport header of the `sk_buff`. This is a *functional* change, and it specifically impacts VXLAN and IP tunnels, including GRE. This means fuzzing efforts need to be laser-focused on these receive paths. The goal is to verify that the transport header is being correctly unset, and importantly, that we don't introduce any regressions in subsequent packet processing after the header removal.

Just to be absolutely certain, I’ll quickly double-check that there aren't any other dependent configs lurking around. Okay, looks like `CONFIG_VXLAN` alone covers `vxlan_rcv`. And for `__iptunnel_pull_header` through GRE, `CONFIG_NET_IPGRE` and `CONFIG_IPV6_GRE` are the critical ones.

Alright, that's the analysis done, time to call `set-results`.

{
  "EnableConfigs": [
    "VXLAN",
    "NET_IPGRE",
    "IPV6_GRE"
  ],
  "FocusSymbols": [
    "vxlan_rcv",
    "__iptunnel_pull_header"
  ],
  "Reasoning": "The patch modifies `vxlan_rcv` and `__iptunnel_pull_header` to unset the transport header of the `sk_buff`. This is a functional change in the networking stack affecting VXLAN and IP tunnels (like GRE). Fuzzing should focus on these receive paths to ensure the transport header is correctly unset and doesn't cause regressions in subsequent packet processing.",
  "WorthFuzzing": true
}

{
  "EnableConfigs": [
    "VXLAN",
    "NET_IPGRE",
    "IPV6_GRE"
  ],
  "FocusSymbols": [
    "vxlan_rcv",
    "__iptunnel_pull_header"
  ],
  "Reasoning": "The patch modifies `vxlan_rcv` and `__iptunnel_pull_header` to unset the transport header of the `sk_buff`. This is a functional change in the networking stack affecting VXLAN and IP tunnels (like GRE). Fuzzing should focus on these receive paths to ensure the transport header is correctly unset and doesn't cause regressions in subsequent packet processing.",
  "WorthFuzzing": true
}