Description
In the Linux kernel, the following vulnerability has been resolved: netfilter: ebtables: fix OOB read in compat_mtw_from_user Luxiao Xu says: The function compat_mtw_from_user() converts ebtables extensions from 32-bit user structures to kernel native structures. However, it lacks proper validation of the user-supplied match_size/target_size. When certain extensions are processed, the kernel-side translation logic may perform memory accesses based on the extension's expected size. If the user provides a size smaller than what the extension requires, it results in an out-of-bounds read as reported by KASAN. This fix introduces a check to ensure match_size is at least as large as the extension's required compatsize. This covers matches, watchers, and targets, while maintaining compatibility with standard targets. AFAIU this is relevant for matches that need to go though match->compat_from_user() call. Those that use plain memcpy with the user-provided size are ok because the caller checks that size vs the start of the next rule entry offset (which itself is checked vs. total size copied from userspace). The ->compat_from_user() callbacks assume they can read compatsize bytes, so they need this extra check. Based on an earlier patch from Luxiao Xu.
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
81e675c227ec60a0bdcbb547dc530ebee23ff931 to < d7a8fb6f10d55a1c37b0bf8c20cca24dffd76e00affected81e675c227ec60a0bdcbb547dc530ebee23ff931 to < 21af4c030567d2e6c89bb927bc18b51fba52a400affected81e675c227ec60a0bdcbb547dc530ebee23ff931 to < dad9ebf8107955bb54bd3f9cf22591b6ff37bac1affected81e675c227ec60a0bdcbb547dc530ebee23ff931 to < a27cb7325a6c69970041c7f8541fafed5a1ea3ecaffected81e675c227ec60a0bdcbb547dc530ebee23ff931 to < 7ad0e463fc7eafae2141cc38054264636f8b3e94affected81e675c227ec60a0bdcbb547dc530ebee23ff931 to < bf8e8eac7ede51dc318e06acef5a896dcbba7595affected81e675c227ec60a0bdcbb547dc530ebee23ff931 to < fcc4c043d137e7f1de4673dba1f3116e45377c67affected81e675c227ec60a0bdcbb547dc530ebee23ff931 to < f438d1786d657d57790c5d138d6db3fc9fdac392affected
Linux Linux
Default version status: affected
2.6.34affected0 to < 2.6.34unaffected5.10.259 to ≤ 5.10.*unaffected5.15.210 to ≤ 5.15.*unaffected6.1.176 to ≤ 6.1.*unaffected6.6.143 to ≤ 6.6.*unaffected6.12.93 to ≤ 6.12.*unaffected6.18.35 to ≤ 6.18.*unaffected7.0.12 to ≤ 7.0.*unaffected7.1 to ≤ *unaffected
References
- https://git.kernel.org/stable/c/d7a8fb6f10d55a1c37b0bf8c20cca24dffd76e00 ↗
- https://git.kernel.org/stable/c/21af4c030567d2e6c89bb927bc18b51fba52a400 ↗
- https://git.kernel.org/stable/c/dad9ebf8107955bb54bd3f9cf22591b6ff37bac1 ↗
- https://git.kernel.org/stable/c/a27cb7325a6c69970041c7f8541fafed5a1ea3ec ↗
- https://git.kernel.org/stable/c/7ad0e463fc7eafae2141cc38054264636f8b3e94 ↗
- https://git.kernel.org/stable/c/bf8e8eac7ede51dc318e06acef5a896dcbba7595 ↗
- https://git.kernel.org/stable/c/fcc4c043d137e7f1de4673dba1f3116e45377c67 ↗
- https://git.kernel.org/stable/c/f438d1786d657d57790c5d138d6db3fc9fdac392 ↗