VYPR
← All advisories
High severity7.8NVD Advisory· Published Apr 17, 2024· Updated Jun 17, 2026

CVE-2024-26883

CVE-2024-26883

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.

AI Insight

LLM-synthesized narrative grounded in this CVE's description and references.

Affected products

118

Patches

Vulnerability mechanics

References

12

News mentions

0

No linked articles in our index yet.