CVE-2025-39843

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description The set track prepare() function in the Linux kernel can incur lock recursion. This issue arises when called from hrtimer start range ns while holding the per cpu(hrtimer bases)[n].lock. When CONFIG DEBUG OBJECTS TIMERS is enabled, this can wake up kswapd within set track prepare(), attempting to re-acquire the same lock, leading to a deadlock. The issue is addressed by preventing kswapd from being woken up by passing allocation flags that do not contain GFP KSWAPD RECLAIM in the debug objects fill pool() case. The GFP DIRECT RECLAIM flag is also masked out within slab alloc() as it has preemption disabled.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.