dm-pcache: only hand out initialized cache segments
In the Linux kernel, the following vulnerability has been resolved: dm-pcache: only hand out initialized cache segments get_cache_segment() scans the segment map up to cache->n_segs, the physical device segment count, but cache_segs_init() only initializes the first cache_info->n_segs segments. A crafted image with cache_info->n_segs smaller than the device count leaves the remaining pcache_cache_segment structs zeroed (segment.data == NULL), and the allocator can hand one to cache_kset_close(), which writes through the returned segment's data pointer with no NULL check. Bound the allocator's search to cache_info->n_segs so only initialized segments are ever returned. A conforming cache sets n_segs equal to the device segment count, so this rejects nothing legitimate.
CVE-2026-80956
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-2026-80956
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": "1d57628ff95b32d5cfa8d8f50e07690c161e9cf0",
"lessThan": "83e3116283ed2c6a6a1fa662862a4b4d7d2701a2",
"versionType": "git"
},
{
"status": "affected",
"version": "1d57628ff95b32d5cfa8d8f50e07690c161e9cf0",
"lessThan": "692037ae1a7cfacc2f0c22c6e034c1dfee0e553f",
"versionType": "git"
},
{
"status": "affected",
"version": "1d57628ff95b32d5cfa8d8f50e07690c161e9cf0",
"lessThan": "2df0fc042e299bae3c0f60ea5cd2af9285658e9f",
"versionType": "git"
}
],
"programFiles": [
"drivers/md/dm-pcache/cache_segment.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": "6.18.50",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.4",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"drivers/md/dm-pcache/cache_segment.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-80956
Source reference:
/cveMetadata/cveId
Publisher severity
No explicit severity was provided.
- Event
- #34914 · Revision 1
- Added to Heist Feed
- Publisher date