Bug 2360285 (CVE-2025-23131)

Summary: CVE-2025-23131 kernel: dlm: prevent NPD when writing a positive value to event_done
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: dfreiber, drow, jburrell, vkumar
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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Description OSIDB Bzimport 2025-04-16 15:06:20 UTC
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.

Comment 1 Avinash Hanwate 2025-04-17 06:50:20 UTC
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2025041631-CVE-2025-23131-1a88@gregkh/T