Description
In the Linux kernel, the following vulnerability has been resolved:
net: use skb_header_pointer() for TCPv4 GSO frag_off check
Syzbot reported a KMSAN uninit-value warning in gso_features_check() called from netif_skb_features() [1].
gso_features_check() reads iph->frag_off to decide whether to clear mangleid_features. Accessing the IPv4 header via ip_hdr()/inner_ip_hdr() can rely on skb header offsets that are not always safe for direct dereference on packets injected from PF_PACKET paths.
Use skb_header_pointer() for the TCPv4 frag_off check so the header read is robust whether data is already linear or needs copying.
[1] https://syzkaller.appspot.com/bug?extid=1543a7d954d9c6d00407
Metrics
CVSS 3.1 5.5/10
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HWeakness enumeration
Affected software
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux | >= cbc53e08a793b073e79f42ca33f1f3568703540d, < 362bacb37d88a178bfaefc4484623eae44425a70; >= cbc53e08a793b073e79f42ca33f1f3568703540d, < 5057502630fbc8ce468ff617ff59af275960b537; >= cbc53e08a793b073e79f42ca33f1f3568703540d, < f7a6cd508e9e825a2c69fa9e13d41ee156852f25; >= cbc53e08a793b073e79f42ca33f1f3568703540d, < cc91202fc20a44aab4c206f12a2bfe05da936051; >= cbc53e08a793b073e79f42ca33f1f3568703540d, < d970341cfa5594614c7a6634886c7688b4f5cafd; >= cbc53e08a793b073e79f42ca33f1f3568703540d, < ddc748a391dd8642ba6b2e4fe22e7f2ddf84b7f0 |
| Linux | Linux | 4.7 |
References
- https://git.kernel.org/stable/c/362bacb37d88a178bfaefc4484623eae44425a70
- https://git.kernel.org/stable/c/5057502630fbc8ce468ff617ff59af275960b537
- https://git.kernel.org/stable/c/cc91202fc20a44aab4c206f12a2bfe05da936051Patch
- https://git.kernel.org/stable/c/d970341cfa5594614c7a6634886c7688b4f5cafdPatch
- https://git.kernel.org/stable/c/ddc748a391dd8642ba6b2e4fe22e7f2ddf84b7f0Patch
- https://git.kernel.org/stable/c/f7a6cd508e9e825a2c69fa9e13d41ee156852f25Patch
Timeline
- Published
- May 1, 2026
- Last modified
- Nov 11, 2026
- NVD status
- Modified