CVE-2024-26884: Linux Kernel

High severity, CVSS 7.8. EPSS: 0.3% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix hashtab overflow check on 32-bit arches The hashtab 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. So apply the same fix to hashtab, by moving the overflow check to before the roundup.

Affected products

• Linux Linux Kernel: from 3.19, before 4.19.311 (fixed in 4.19.311); from 4.20, before 5.4.273 (fixed in 5.4.273); from 5.5, before 5.10.214 (fixed in 5.10.214); from 5.11, before 5.15.153 (fixed in 5.15.153); from 5.16, before 6.1.83 (fixed in 6.1.83); from 6.2, before 6.6.23 (fixed in 6.6.23); …

Published 2024-04-17. Last modified 2026-06-17.