Description
In the Linux kernel, the following vulnerability has been resolved: bpf: Guard conntrack opts error writes The conntrack lookup and allocation kfuncs take an opts pointer together with an opts__sz argument. The verifier checks only the memory range described by opts__sz, but the wrappers unconditionally write opts->error whenever the internal lookup or allocation helper returns an error. For an invalid size smaller than the end of opts->error, that write can land outside the verifier-checked range. Keep returning NULL for invalid arguments, but only report the error through opts->error when the supplied size includes the field. This preserves error reporting for the supported 12-byte and 16-byte layouts, and for other invalid sizes that still include opts->error.
References6
- git.kernel.org/stable/c/453f4f1e90de55b6bc297936031b68bef93f2e28
- git.kernel.org/stable/c/63d95c6bbd6fc0e411404188306a1fea456300b0
- git.kernel.org/stable/c/669bc3b345712112d3f033a1953f5a10b15e7c65
- git.kernel.org/stable/c/6f6183a39533d727deaa5061cadae6dd9e6744d0
- git.kernel.org/stable/c/6fd973def4d6cb89aaf7e9b6bc26cac977f6da13
- git.kernel.org/stable/c/dd74c80203842a21b2ebb9f70d1260d9aa20fa05
Metrics
- CVSS 3.1
-
8.8
HIGH
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 6 · as of 11 November 2026
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