md/md-llbitmap: prevent create failure bitmap UAF
In the Linux kernel, the following vulnerability has been resolved: md/md-llbitmap: prevent create failure bitmap UAF llbitmap_create() publishes mddev->bitmap before reading the bitmap superblock. This is needed because llbitmap_read_sb() can initialize a new bitmap and flush it through helpers that use mddev->bitmap. If llbitmap_read_sb() fails, the old cleanup dropped bitmap_info.mutex and freed llbitmap before clearing mddev->bitmap. Readers such as /proc/mdstat rely on bitmap_info.mutex to keep the bitmap pointer stable while collecting bitmap stats, so they could observe the stale pointer after the failed create path released the mutex. Clear mddev->bitmap while still holding bitmap_info.mutex, then free the failed llbitmap after dropping the mutex. This makes mutex-protected readers see either a live bitmap or no bitmap.
CVE-2026-90277
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-2026-90277
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": "930cc4f1af5a1afcd545a6ba00e38921ff8401e0",
"versionType": "git"
},
{
"status": "affected",
"version": "5ab829f1971dc99f2aac10846c378e67fc875abc",
"lessThan": "2f0722435ce3a844dbb66b9bb0a18229dcc8739c",
"versionType": "git"
},
{
"status": "affected",
"version": "5ab829f1971dc99f2aac10846c378e67fc875abc",
"lessThan": "2116c2f0a0e547615886900e2ed8c529c016499b",
"versionType": "git"
}
],
"programFiles": [
"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-llbitmap.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-90277
Source reference:
/cveMetadata/cveId
Publisher severity
No explicit severity was provided.
- Event
- #36635 · Revision 1
- Added to Heist Feed
- Publisher date