drbd: add missing kref_get in handle_write_conflicts
In the Linux kernel, the following vulnerability has been resolved: drbd: add missing kref_get in handle_write_conflicts With `two-primaries` enabled, DRBD tries to detect "concurrent" writes and handle write conflicts, so that even if you write to the same sector simultaneously on both nodes, they end up with the identical data once the writes are completed. In handling "superseeded" writes, we forgot a kref_get, resulting in a premature drbd_destroy_device and use after free, and further to kernel crashes with symptoms. Relevance: No one should use DRBD as a random data generator, and apparently all users of "two-primaries" handle concurrent writes correctly on layer up. That is cluster file systems use some distributed lock manager, and live migration in virtualization environments stops writes on one node before starting writes on the other node. Which means that other than for "test cases", this code path is never taken in real life. FYI, in DRBD 9, things are handled differently nowadays. We still detect "write conflicts", but no longer try to be smart about them. We decided to disconnect hard instead: upper layers must not submit concurrent writes. If they do, that's their fault.
CVE-2025-38708
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-2025-38708
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": "668700b40a7c8727bbd2b3fd4fd22e0ce3f1aeb6",
"lessThan": "0336bfe9c237476bd7c45605a36ca79c2bca62e5",
"versionType": "git"
},
{
"status": "affected",
"version": "668700b40a7c8727bbd2b3fd4fd22e0ce3f1aeb6",
"lessThan": "810cd546a29bfac90ed1328ea01d693d4bd11cb1",
"versionType": "git"
},
{
"status": "affected",
"version": "668700b40a7c8727bbd2b3fd4fd22e0ce3f1aeb6",
"lessThan": "84ef8dd3238330d1795745ece83b19f0295751bf",
"versionType": "git"
},
{
"status": "affected",
"version": "668700b40a7c8727bbd2b3fd4fd22e0ce3f1aeb6",
"lessThan": "57418de35420cedab035aa1da8a26c0499b7f575",
"versionType": "git"
},
{
"status": "affected",
"version": "668700b40a7c8727bbd2b3fd4fd22e0ce3f1aeb6",
"lessThan": "9f53b2433ad248cd3342cc345f56f5c7904bd8c4",
"versionType": "git"
},
{
"status": "affected",
"version": "668700b40a7c8727bbd2b3fd4fd22e0ce3f1aeb6",
"lessThan": "7d483ad300fc0a06f69b019dda8f74970714baf8",
"versionType": "git"
},
{
"status": "affected",
"version": "668700b40a7c8727bbd2b3fd4fd22e0ce3f1aeb6",
"lessThan": "46e3763dcae0ffcf8fcfaff4fc10a90a92ffdd89",
"versionType": "git"
},
{
"status": "affected",
"version": "668700b40a7c8727bbd2b3fd4fd22e0ce3f1aeb6",
"lessThan": "3a896498f6f577e57bf26aaa93b48c22b6d20c20",
"versionType": "git"
},
{
"status": "affected",
"version": "668700b40a7c8727bbd2b3fd4fd22e0ce3f1aeb6",
"lessThan": "00c9c9628b49e368d140cfa61d7df9b8922ec2a8",
"versionType": "git"
}
],
"programFiles": [
"drivers/block/drbd/drbd_receiver.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "4.5"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "4.5",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.4.297",
"versionType": "semver",
"lessThanOrEqual": "5.4.*"
},
{
"status": "unaffected",
"version": "5.10.241",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.190",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.149",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.103",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.43",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.15.11",
"versionType": "semver",
"lessThanOrEqual": "6.15.*"
},
{
"status": "unaffected",
"version": "6.16.2",
"versionType": "semver",
"lessThanOrEqual": "6.16.*"
},
{
"status": "unaffected",
"version": "6.17",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"drivers/block/drbd/drbd_receiver.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2025-38708
Source reference:
/cveMetadata/cveId
Publisher severity
critical
Source reference: /containers/cna/metrics
- Event
- #27050 · Revision 1
- Added to Heist Feed
- Publisher date