PT-2025-46609 · Linux+3 · Linux Kernel+3
Published
2025-08-26
·
Updated
2026-05-19
·
CVE-2025-40134
CVSS v2.0
3.8
Low
| Vector | AV:L/AC:H/Au:S/C:N/I:N/A:C |
Name of the Vulnerable Software and Affected Versions
Linux kernel versions prior to 6.6.0-g7e52f5f0ca9b
Description
The Linux kernel contains a flaw in the device mapper (dm) subsystem related to a race condition between device suspend and table load. This can lead to a NULL pointer dereference within the
dm suspend() function. The issue arises when suspend is initiated before the table load process is complete. Specifically, the problem occurs during the initialization of the request queue (blk mq init allocated queue) where the q->mq ops pointer is set before the q->tag set is initialized, potentially leading to a NULL pointer access. The fix involves checking for a valid table (map) before performing request-based suspend and waiting for target I/O. If the map is NULL, table-dependent suspend steps are skipped to prevent the dereference. This is safe because I/O will fail early in the DM layer if no table is loaded. The vulnerable function is dm suspend().Recommendations
Update to a version later than 6.6.0-g7e52f5f0ca9b.
Exploit
Fix
Race Condition
NULL Pointer Dereference
Found an issue in the description? Have something to add? Feel free to write us 👾
Related Identifiers
Affected Products
Debian
Linuxmint
Linux Kernel
Ubuntu