CVE-2024-47703: bpf, lsm: Add check for BPF LSM return value

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2024-10-21 · updated 2026-08-04

Description

In the Linux kernel, the following vulnerability has been resolved: bpf, lsm: Add check for BPF LSM return value A bpf prog returning a positive number attached to file_alloc_security hook makes kernel panic. This happens because file system can not filter out the positive number returned by the LSM prog using IS_ERR, and misinterprets this positive number as a file pointer. Given that hook file_alloc_security never returned positive number before the introduction of BPF LSM, and other BPF LSM hooks may encounter similar issues, this patch adds LSM return value check in verifier, to ensure no unexpected value is returned.

Affected products

Linux kernel: from 5.7 before 6.10.13; from 6.11 before 6.11.2 — fixed in 6.10.13, 6.11.2

How to fix

Upgrade to a fixed version: Linux kernel 6.10.13, 6.11.2. Check the vendor advisory for mitigations.

References

Get alerted when CVE-2024-47703 or the next vulnerability affects your stack