CVE-2026-46023: dm mirror: fix integer overflow in create_dirty_log()

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-05-27 · updated 2026-10-15
Weakness: CWE-190

Description

In the Linux kernel, the following vulnerability has been resolved: dm mirror: fix integer overflow in create_dirty_log() The argument count calculation in create_dirty_log() performs `*args_used = 2 + param_count` before validating against argc. When a user provides a param_count close to UINT_MAX via the device mapper table string, this unsigned addition wraps around to a small value, causing the subsequent `argc < *args_used` check to be bypassed. The overflowed param_count is then passed as argc to dm_dirty_log_create(), where it can cause out-of-bounds reads on the argv array. Fix by comparing param_count against argc - 2 before performing the addition, following the same pattern used by parse_features() in the same file. Since argc >= 2 is already guaranteed, the subtraction is safe.

Affected products

Linux kernel: from 2.6.12.1 before 5.10.258; from 5.11 before 5.15.209; from 5.16 before 6.1.175; from 6.2 before 6.6.140; from 6.7 before 6.12.86; from 6.13 before 6.18.27 — fixed in 5.10.258, 5.15.209, 6.1.175, 6.12.86, 6.18.27, 6.6.140

How to fix

Upgrade to a fixed version: Linux kernel 5.10.258, 5.15.209, 6.1.175, 6.12.86. Check the vendor advisory for mitigations.

References

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