CVE-2026-46023

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.

References

• https://git.kernel.org/stable/c/17a08791d428885d00e510864283a7b839792368
• https://git.kernel.org/stable/c/35f6b3281efd44d19110574663bc17a610bc73b9
• https://git.kernel.org/stable/c/47dad9eea75d33212d3d2cea10e7ed6a1bfc0713
• https://git.kernel.org/stable/c/4c788c6f921b22f9b6c3f316c4a071c05683e7de
• https://git.kernel.org/stable/c/87c99a50e0fdc68a5b9b52a94d49452cd3ff02ca