md/md-llbitmap: stop daemon timer rearm on destroy
In the Linux kernel, the following vulnerability has been resolved: md/md-llbitmap: stop daemon timer rearm on destroy llbitmap_destroy() deletes pending_timer before flushing md_llbitmap_io_wq. However, daemon_work can still be queued or running after the timer has been deleted, and the daemon path can arm pending_timer again when it finds dirty chunks that are not ready to flush yet. If that happens during teardown, pending_timer can remain armed after llbitmap is freed and later dereference freed memory. Add a BITMAP_SHUTDOWN bit to llbitmap->flags, set it before deleting the timer, and make the timer and daemon paths stop queueing or rearming work once teardown starts. Cancel daemon_work before flushing the shared workqueue so no already queued daemon instance can race with the free. Use timer_shutdown_sync() so a daemon instance that passed the shutdown check before teardown cannot rearm the timer afterward. BITMAP_SHUTDOWN is a runtime-only state. Mask it out when reading and updating the llbitmap superblock so the shutdown state is never loaded from disk or persisted to disk.
CVE-2026-90276
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-90276
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "5ab829f1971dc99f2aac10846c378e67fc875abc",
"lessThan": "c55aa6c17f019b6296952d336939891efa084c06",
"versionType": "git"
},
{
"status": "affected",
"version": "5ab829f1971dc99f2aac10846c378e67fc875abc",
"lessThan": "bb7f92d58fca9a9f06f3f51a82481c5f0bbbd46c",
"versionType": "git"
},
{
"status": "affected",
"version": "5ab829f1971dc99f2aac10846c378e67fc875abc",
"lessThan": "5553d64e01d9a995be6c3de38501c6dd4ceede3b",
"versionType": "git"
}
],
"programFiles": [
"drivers/md/md-bitmap.h",
"drivers/md/md-llbitmap.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "6.18"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "6.18",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.18.52",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.6",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"drivers/md/md-bitmap.h",
"drivers/md/md-llbitmap.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-90276
Source reference:
/cveMetadata/cveId
Publisher severity
No explicit severity was provided.
- Event
- #36634 · Revision 1
- Added to Heist Feed
- Publisher date