Description
In the Linux kernel, the following vulnerability has been resolved: dlm: prevent NPD when writing a positive value to event_done do_uevent returns the value written to event_done. In case it is a positive value, new_lockspace would undo all the work, and lockspace would not be set. __dlm_new_lockspace, however, would treat that positive value as a success due to commit 8511a2728ab8 ("dlm: fix use count with multiple joins"). Down the line, device_create_lockspace would pass that NULL lockspace to dlm_find_lockspace_local, leading to a NULL pointer dereference. Treating such positive values as successes prevents the problem. Given this has been broken for so long, this is unlikely to break userspace expectations.
Affected products
linux: linux kernel
References8
- git.kernel.org/stable/c/8e2bad543eca5c25cd02cbc63d72557934d45f13 Patch
- git.kernel.org/stable/c/b73c4ad4d387fe5bc988145bd9f1bc0de76afd5c Patch
- git.kernel.org/stable/c/10b7a59814765d18d43555c9cef4eb3048b7e8a3
- git.kernel.org/stable/c/7109d69bec6edce546dc870e66bd2b668a3d5549
- git.kernel.org/stable/c/a1c41aebb184d9228a440dcb6761224e65b0e49a
- git.kernel.org/stable/c/c7837e2c96559663c33f43da403d9cf3cf77cfa7
- git.kernel.org/stable/c/ee28d99d789b077565cbe0377374d1e826c64d93
- cert-portal.siemens.com/productcert/html/ssa-784472.html
Metrics
- CVSS 3.1
-
5.5
MEDIUM
Score source: NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 9 · as of 7 November 2026
- CWE
- CWE-476
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.