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.
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cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published: 2024-04-17T10:27:39.672Z

Updated: 2024-08-02T00:21:05.540Z

Reserved: 2024-02-19T14:20:24.185Z

Link: CVE-2024-26884

cve-icon Vulnrichment

Updated: 2024-06-17T19:18:34.078Z

cve-icon NVD

Status : Modified

Published: 2024-04-17T11:15:10.163

Modified: 2024-06-27T12:15:22.003

Link: CVE-2024-26884

cve-icon Redhat

Severity : Low

Publid Date: 2024-04-17T00:00:00Z

Links: CVE-2024-26884 - Bugzilla