CVE-2025-39736
Description
In the Linux kernel, the following vulnerability has been resolved: mm/kmemleak: avoid deadlock by moving pr_warn() outside kmemleak_lock When netpoll is enabled, calling pr_warn_once() while holding kmemleak_lock in mem_pool_alloc() can cause a deadlock due to lock inversion with the netconsole subsystem. This occurs because pr_warn_once() may trigger netpoll, which eventually leads to __alloc_skb() and back into kmemleak code, attempting to reacquire kmemleak_lock. This is the path for the deadlock. mem_pool_alloc() -> raw_spin_lock_irqsave(&kmemleak_lock, flags); -> pr_warn_once() -> netconsole subsystem -> netpoll -> __alloc_skb -> __create_object -> raw_spin_lock_irqsave(&kmemleak_lock, flags); Fix this by setting a flag and issuing the pr_warn_once() after kmemleak_lock is released.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
OS impact
| OS | Version | Status | Fixed in |
|---|---|---|---|
| sles | affected | | |
| debian | bookworm | fixed | 6.1.153-1 |
| debian | bullseye | fixed | 5.10.244-1 |
| debian | forky | fixed | 6.16.3-1 |
| debian | sid | fixed | 6.16.3-1 |
| debian | trixie | fixed | 6.12.43-1 |
| linux-kernel | affected | 5.4.297 | |
| linux-kernel | 6.17 | affected | |
| debian | 11.0 | affected | |
References
- https://git.kernel.org/stable/c/08f70be5e406ce47c822f2dd11c1170ca259605b
- https://git.kernel.org/stable/c/1da95d3d4b7b1d380ebd87b71a61e7e6aed3265d
- https://git.kernel.org/stable/c/47b0f6d8f0d2be4d311a49e13d2fd5f152f492b2
- https://git.kernel.org/stable/c/4b0151e1d468eb2667c37b7af99b3c075072d334
- https://git.kernel.org/stable/c/62879faa8efe8d8a9c7bf7606ee9c068012d7dac
- https://git.kernel.org/stable/c/a0854de00ce2ee27edf39037e7836ad580eb3350
- https://git.kernel.org/stable/c/a181b228b37a6a5625dad2bb4265bb7abb673e9f
- https://git.kernel.org/stable/c/c7b6ea0ede687e7460e593c5ea478f50aa41682a
- https://git.kernel.org/stable/c/f249d32bb54876b4b6c3ae071af8ddca77af390b
- https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html
- https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html
- https://cert-portal.siemens.com/productcert/html/ssa-032379.html
- https://www.suse.com/security/cve/CVE-2025-39736.html
- https://security-tracker.debian.org/tracker/CVE-2025-39736
CWEs
CWE-667
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.