fou: Don't allow 0 for FOU_ATTR_IPPROTO.
In the Linux kernel, the following vulnerability has been resolved: fou: Don't allow 0 for FOU_ATTR_IPPROTO. fou_udp_recv() has the same problem mentioned in the previous patch. If FOU_ATTR_IPPROTO is set to 0, skb is not freed by fou_udp_recv() nor "resubmit"-ted in ip_protocol_deliver_rcu(). Let's forbid 0 for FOU_ATTR_IPPROTO.
02 / AFFECTED SOFTWARE
Affected packages
03 / CONNECTIONS
Connected vulnerabilities
04 / EVIDENCE
Source records
In the Linux kernel, the following vulnerability has been resolved: fou: Don't allow 0 for FOU_ATTR_IPPROTO. fou_udp_recv() has the same problem mentioned in the previous patch. If FOU_ATTR_IPPROTO is set to 0, skb is not freed by fou_udp_recv() nor "resubmit"-ted in ip_protocol_deliver_rcu(). Let's forbid 0 for FOU_ATTR_IPPROTO.
05 / REFERENCES
Further evidence
- https://cert-portal.siemens.com/productcert/html/ssa-019113.html
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- https://git.kernel.org/stable/c/1cc98b8887cabb1808d2f4a37cd10a7be7574771
- https://git.kernel.org/stable/c/611ef4bd9c73d9e6d87bed57a635ff1fdd8c91ea
- https://git.kernel.org/stable/c/6e983789b7588ee59cbf303583546c043bad8e19
- https://git.kernel.org/stable/c/7a9bc9e3f42391e4c187e099263cf7a1c4b69ff5
- https://git.kernel.org/stable/c/9b75dff8446ec871030d8daf5a69e74f5fe8b956
- https://git.kernel.org/stable/c/b7db31a52c3862a1a32202a273a4c32e7f5f4823
- https://git.kernel.org/stable/c/c7498f9bc390479ccfad7c7f2332237ff4945b03
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/23xxx/CVE-2026-23083.json
- https://nvd.nist.gov/vuln/detail/CVE-2026-23083