Description
In the Linux kernel, the following vulnerability has been resolved: net: fix __dst_negative_advice() race __dst_negative_advice() does not enforce proper RCU rules when sk->dst_cache must be cleared, leading to possible UAF. RCU rules are that we must first clear sk->sk_dst_cache, then call dst_release(old_dst). Note that sk_dst_reset(sk) is implementing this protocol correctly, while __dst_negative_advice() uses the wrong order. Given that ip6_negative_advice() has special logic against RTF_CACHE, this means each of the three ->negative_advice() existing methods must perform the sk_dst_reset() themselves. Note the check against NULL dst is centralized in __dst_negative_advice(), there is no need to duplicate it in various callbacks. Many thanks to Clement Lecigne for tracking this issue. This old bug became visible after the blamed commit, using UDP sockets.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Linux Linux
Default version status: unaffected
a87cb3e48ee86d29868d3f59cfb9ce1a8fa63314 to < 051c0bde9f0450a2ec3d62a86d2a0d2fad117f13affecteda87cb3e48ee86d29868d3f59cfb9ce1a8fa63314 to < db0082825037794c5dba9959c9de13ca34cc5e72affecteda87cb3e48ee86d29868d3f59cfb9ce1a8fa63314 to < 2295a7ef5c8c49241bff769e7826ef2582e532a6affecteda87cb3e48ee86d29868d3f59cfb9ce1a8fa63314 to < eacb8b195579c174a6d3e12a9690b206eb7f28cfaffecteda87cb3e48ee86d29868d3f59cfb9ce1a8fa63314 to < 81dd3c82a456b0015461754be7cb2693991421b4affecteda87cb3e48ee86d29868d3f59cfb9ce1a8fa63314 to < 5af198c387128a9d2ddd620b0f0803564a4d4508affecteda87cb3e48ee86d29868d3f59cfb9ce1a8fa63314 to < b8af8e6118a6605f0e495a58d591ca94a85a50fcaffecteda87cb3e48ee86d29868d3f59cfb9ce1a8fa63314 to < 92f1655aa2b2294d0b49925f3b875a634bd3b59eaffected
Linux Linux
Default version status: affected
4.6affected0 to < 4.6unaffected4.19.316 to ≤ 4.19.*unaffected5.4.278 to ≤ 5.4.*unaffected5.10.219 to ≤ 5.10.*unaffected5.15.161 to ≤ 5.15.*unaffected6.1.94 to ≤ 6.1.*unaffected6.6.34 to ≤ 6.6.*unaffected6.9.4 to ≤ 6.9.*unaffected6.10 to ≤ *unaffected
References
- https://git.kernel.org/stable/c/051c0bde9f0450a2ec3d62a86d2a0d2fad117f13 ↗
- https://git.kernel.org/stable/c/db0082825037794c5dba9959c9de13ca34cc5e72 ↗
- https://git.kernel.org/stable/c/2295a7ef5c8c49241bff769e7826ef2582e532a6 ↗
- https://git.kernel.org/stable/c/eacb8b195579c174a6d3e12a9690b206eb7f28cf ↗
- https://git.kernel.org/stable/c/81dd3c82a456b0015461754be7cb2693991421b4 ↗
- https://git.kernel.org/stable/c/5af198c387128a9d2ddd620b0f0803564a4d4508 ↗
- https://git.kernel.org/stable/c/b8af8e6118a6605f0e495a58d591ca94a85a50fc ↗
- https://git.kernel.org/stable/c/92f1655aa2b2294d0b49925f3b875a634bd3b59e ↗
- https://lists.debian.org/debian-lts-announce/2024/06/msg00020.html ↗
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2024-36971 ↗