Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: bpf: Fix stackmap overflow check on 32-bit arches The stackmap code relies on roundup_pow_of_two() to compute the number of hash buckets, and contains an overflow check by checking if the resulting value is 0. However, on 32-bit arches, the roundup code itself can overflow by doing a 32-bit left-shift of an unsigned long value, which is undefined behaviour, so it is not guaranteed to truncate neatly. This was triggered by syzbot on the DEVMAP_HASH type, which contains the same check, copied from the hashtab code. The commit in the fixes tag actually attempted to fix this, but the fix did not account for the UB, so the fix only works on CPUs where an overflow does result in a neat truncation to zero, which is not guaranteed. Checking the value before rounding does not have this problem.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Debian | Debian Linux | 10.0 |
| Linux | Linux Kernel | >= 4.9.258, < 4.10 |
Related Weaknesses (CWE)
References
- https://git.kernel.org/stable/c/0971126c8164abe2004b8536b49690a0d6005b0aPatch
- https://git.kernel.org/stable/c/15641007df0f0d35fa28742b25c2a7db9dcd6895Patch
- https://git.kernel.org/stable/c/21e5fa4688e1a4d3db6b72216231b24232f75c1dPatch
- https://git.kernel.org/stable/c/43f798b9036491fb014b55dd61c4c5c3193267d0Patch
- https://git.kernel.org/stable/c/7070b274c7866a4c5036f8d54fcaf315c64ac33aPatch
- https://git.kernel.org/stable/c/7a4b21250bf79eef26543d35bd390448646c536bPatch
- https://git.kernel.org/stable/c/ca1f06e72dec41ae4f76e7b1a8a97265447b46aePatch
- https://git.kernel.org/stable/c/d0e214acc59145ce25113f617311aa79dda39cb3Patch
- https://git.kernel.org/stable/c/f06899582ccee09bd85d0696290e3eaca9aa042dPatch
- https://git.kernel.org/stable/c/0971126c8164abe2004b8536b49690a0d6005b0aPatch
- https://git.kernel.org/stable/c/15641007df0f0d35fa28742b25c2a7db9dcd6895Patch
- https://git.kernel.org/stable/c/21e5fa4688e1a4d3db6b72216231b24232f75c1dPatch
- https://git.kernel.org/stable/c/43f798b9036491fb014b55dd61c4c5c3193267d0Patch
- https://git.kernel.org/stable/c/7070b274c7866a4c5036f8d54fcaf315c64ac33aPatch
- https://git.kernel.org/stable/c/7a4b21250bf79eef26543d35bd390448646c536bPatch
FAQ
What is CVE-2024-26883?
CVE-2024-26883 is a vulnerability with a CVSS score of 7.8 (HIGH). In the Linux kernel, the following vulnerability has been resolved: bpf: Fix stackmap overflow check on 32-bit arches The stackmap code relies on roundup_pow_of_two() to compute the number of hash b...
How severe is CVE-2024-26883?
CVE-2024-26883 has been rated HIGH with a CVSS base score of 7.8/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2024-26883?
Check the references section above for vendor advisories and patch information. Affected products include: Debian Debian Linux, Linux Linux Kernel.