dm thin metadata: fix metadata snapshot consistency on commit failure
In the Linux kernel, the following vulnerability has been resolved: dm thin metadata: fix metadata snapshot consistency on commit failure __reserve_metadata_snap() and __release_metadata_snap() modify the superblock's held_root directly in the block_manager's buffer. If the subsequent metadata commit fails, the held_root gets flushed to disk through the abort_transaction path, resulting in inconsistent metadata. Reproducer 1: __reserve_metadata_snap() 1. Create a 2 MiB metadata device and make the region after the 14th block inaccessible, to trigger metadata commit failure in the subsequent reserve_metadata_snap operation. The 14th block will be the shadow destination for the index block. dmsetup create tmeta --table "0 112 linear /dev/sdc 0 112 3984 error" 2. Create a 16 MiB thin-pool dmsetup create tdata --table "0 32768 zero" dd if=/dev/zero of=/dev/mapper/tmeta bs=4k count=1 dmsetup create tpool --table "0 32768 thin-pool /dev/mapper/tmeta \ /dev/mapper/tdata 128 0 1 skip_block_zeroing" 3. Take a metadata snapshot to trigger metadata commit failure and transaction abort. However, the held_root is written to disk, breaking metadata consistency. dmsetup message tpool 0 "reserve_metadata_snap" thin_check v1.2.2 result: Bad reference count for metadata block 6. Expected 2, but space map contains 1. Bad reference count for metadata block 7. Expected 2, but space map contains 1. Bad reference count for metadata block 13. Expected 1, but space map contains 0. Reproducer 2: __rel
CVE-2026-72108
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-2026-72108
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": "991d9fa02da0dd1f843dc011376965e0c8c6c9b5",
"lessThan": "4af993468193cf4cd32ba5748786e7801945f7d2",
"versionType": "git"
},
{
"status": "affected",
"version": "991d9fa02da0dd1f843dc011376965e0c8c6c9b5",
"lessThan": "abf2fae92cbe68945028987d498cc72f8f0e23a8",
"versionType": "git"
},
{
"status": "affected",
"version": "991d9fa02da0dd1f843dc011376965e0c8c6c9b5",
"lessThan": "5efb1a7734ed4035fa4fdc3716bdb84621f27cf6",
"versionType": "git"
},
{
"status": "affected",
"version": "991d9fa02da0dd1f843dc011376965e0c8c6c9b5",
"lessThan": "3dc9ae1029320d77472c44965e572f176949cd63",
"versionType": "git"
},
{
"status": "affected",
"version": "991d9fa02da0dd1f843dc011376965e0c8c6c9b5",
"lessThan": "b5f9a31c51cbb374a1713c3494f8660ab070f035",
"versionType": "git"
},
{
"status": "affected",
"version": "991d9fa02da0dd1f843dc011376965e0c8c6c9b5",
"lessThan": "7f76245960a332f39b08cc556e675d1765dc5bbb",
"versionType": "git"
},
{
"status": "affected",
"version": "991d9fa02da0dd1f843dc011376965e0c8c6c9b5",
"lessThan": "9f1a0d27586ceab055e6b050e3731ce3c6b2c4f0",
"versionType": "git"
},
{
"status": "affected",
"version": "991d9fa02da0dd1f843dc011376965e0c8c6c9b5",
"lessThan": "5bcd4d3058ebaf46ad2e163829d87dd4870c7a45",
"versionType": "git"
}
],
"programFiles": [
"drivers/md/dm-thin-metadata.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "3.2"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "3.2",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.10.261",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.212",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.178",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.145",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.97",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.40",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.1.5",
"versionType": "semver",
"lessThanOrEqual": "7.1.*"
},
{
"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"drivers/md/dm-thin-metadata.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-72108
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #41876 · Revision 1
- Added to Heist Feed
- Publisher date