drbd: add missing kref_get in handle_write_conflicts (Linux Linux)

CVE-2025-38708
CRITICAL 9.8

At a glance

Source
NVD
EPSS
EPSS 0.38 % · percentile 32 ()
State
PUBLISHED
Published
Updated
Assigner
Linux
NVD status
Modified

Description

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.

Weaknesses (CWE)

References

Scores

VersionScoreVectorScored by
CVSS 3.1CRITICAL 9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HLinux
CVSS 3.1CRITICAL 9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HNVD · 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Secondary)
CVSS 3.1HIGH 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HNVD · nvd@nist.gov (Primary)

European references

CERT-FR advisories

Affected configurations (NVD CPE)

Affected products

ProductVersions
Linux · Linuxaffected 668700b40a7c8727bbd2b3fd4fd22e0ce3f1aeb6 < 0336bfe9c237476bd7c45605a36ca79c2bca62e5 ; affected 668700b40a7c8727bbd2b3fd4fd22e0ce3f1aeb6 < 810cd546a29bfac90ed1328ea01d693d4bd11cb1 ; affected 668700b40a7c8727bbd2b3fd4fd22e0ce3f1aeb6 < 84ef8dd3238330d1795745ece83b19f0295751bf ; affected 668700b40a7c8727bbd2b3fd4fd22e0ce3f1aeb6 < 57418de35420cedab035aa1da8a26c0499b7f575 ; affected 668700b40a7c8727bbd2b3fd4fd22e0ce3f1aeb6 < 9f53b2433ad248cd3342cc345f56f5c7904bd8c4 ; affected 668700b40a7c8727bbd2b3fd4fd22e0ce3f1aeb6 < 7d483ad300fc0a06f69b019dda8f74970714baf8
Linux · Linuxaffected 4.5 ; unaffected 0 < 4.5 ; unaffected 5.4.297 ≤ 5.4.* ; unaffected 5.10.241 ≤ 5.10.* ; unaffected 5.15.190 ≤ 5.15.* ; unaffected 6.1.149 ≤ 6.1.*

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD