CVE-2025-40125

blk-mq: check kobject state_in_sysfs before deleting in blk_mq_unregister_hctx

State: Published
Severity: Not scored
Published: Nov 12, 2025
Updated: May 11, 2026
Reserved: Apr 16, 2025

Description

In the Linux kernel, the following vulnerability has been resolved:

blk-mq: check kobject state_in_sysfs before deleting in blk_mq_unregister_hctx

In __blk_mq_update_nr_hw_queues() the return value of blk_mq_sysfs_register_hctxs() is not checked. If sysfs creation for hctx fails, later changing the number of hw_queues or removing disk will trigger the following warning:

kernfs: can not remove 'nr_tags', no directory WARNING: CPU: 2 PID: 637 at fs/kernfs/dir.c:1707 kernfs_remove_by_name_ns+0x13f/0x160 Call Trace: remove_files.isra.1+0x38/0xb0 sysfs_remove_group+0x4d/0x100 sysfs_remove_groups+0x31/0x60 __kobject_del+0x23/0xf0 kobject_del+0x17/0x40 blk_mq_unregister_hctx+0x5d/0x80 blk_mq_sysfs_unregister_hctxs+0x94/0xd0 blk_mq_update_nr_hw_queues+0x124/0x760 nullb_update_nr_hw_queues+0x71/0xf0 [null_blk] nullb_device_submit_queues_store+0x92/0x120 [null_blk]

kobjct_del() was called unconditionally even if sysfs creation failed. Fix it by checkig the kobject creation statusbefore deleting it.

Scores

The record has no CVSS score.

Weaknesses

The record names no weakness.

Affected Products

Product	Versions
LinuxLinux	477e19dedc9d3e1f4443a1d4ae00572a988120ea to before a8c53553f1833cc2d14175d2d72cf37193a01898Affected 477e19dedc9d3e1f4443a1d4ae00572a988120ea to before cc14ea21c4e658814d737ed4dedde6cd626a15adAffected 477e19dedc9d3e1f4443a1d4ae00572a988120ea to before 4b97e99b87a773d52699521d40864f3ec888e9a6Affected 477e19dedc9d3e1f4443a1d4ae00572a988120ea to before 6e7dadc5763c48eb3b9b91265a21f312599ebb2cAffected 477e19dedc9d3e1f4443a1d4ae00572a988120ea to before 06c4826b1d900611096e4621e93133db57e13911Affected 477e19dedc9d3e1f4443a1d4ae00572a988120ea to before babc634e9fe2803962dba98a07587e835dbc0731Affected 477e19dedc9d3e1f4443a1d4ae00572a988120ea to before d5ddd76ee52bdc16e9f8b1e7791291e785dab032Affected 477e19dedc9d3e1f4443a1d4ae00572a988120ea to before 4c7ef92f6d4d08a27d676e4c348f4e2922cab3edAffected
LinuxLinux	4.20Affected before 4.20Not affected 5.4.301 through 5.4.Not affected 5.10.246 through 5.10.Not affected 5.15.195 through 5.15.Not affected 6.1.156 through 6.1.Not affected 6.6.112 through 6.6.Not affected 6.12.53 through 6.12.Not affected 6.17.3 through 6.17.*Not affected 6.18 and laterNot affected

Product

Versions

LinuxLinux

477e19dedc9d3e1f4443a1d4ae00572a988120ea to before a8c53553f1833cc2d14175d2d72cf37193a01898Affected
477e19dedc9d3e1f4443a1d4ae00572a988120ea to before cc14ea21c4e658814d737ed4dedde6cd626a15adAffected
477e19dedc9d3e1f4443a1d4ae00572a988120ea to before 4b97e99b87a773d52699521d40864f3ec888e9a6Affected
477e19dedc9d3e1f4443a1d4ae00572a988120ea to before 6e7dadc5763c48eb3b9b91265a21f312599ebb2cAffected
477e19dedc9d3e1f4443a1d4ae00572a988120ea to before 06c4826b1d900611096e4621e93133db57e13911Affected
477e19dedc9d3e1f4443a1d4ae00572a988120ea to before babc634e9fe2803962dba98a07587e835dbc0731Affected
477e19dedc9d3e1f4443a1d4ae00572a988120ea to before d5ddd76ee52bdc16e9f8b1e7791291e785dab032Affected
477e19dedc9d3e1f4443a1d4ae00572a988120ea to before 4c7ef92f6d4d08a27d676e4c348f4e2922cab3edAffected

LinuxLinux

4.20Affected
before 4.20Not affected
5.4.301 through 5.4.*Not affected
5.10.246 through 5.10.*Not affected
5.15.195 through 5.15.*Not affected
6.1.156 through 6.1.*Not affected
6.6.112 through 6.6.*Not affected
6.12.53 through 6.12.*Not affected
6.17.3 through 6.17.*Not affected
6.18 and laterNot affected

References

Every record here comes from the CVE Program’s CVE List. © 1999–2026 The MITRE Corporation. CVE is a registered trademark of The MITRE Corporation. The records are reproduced under the CVE Program terms of use.