CVE-2026-89749

In the Linux kernel, the following vulnerability has been resolved:

tracing: Fix crash passing ERR_PTR to kthread_stop()

event_test_stuff() calls kthread_run() and unconditionally passes the

returned task_struct pointer to kthread_stop(). kthread_run() returns an

error pointer such as ERR_PTR(-ENOMEM) when kthread creation fails, for

example under memory pressure during the boot-time event self-test.

kthread_stop() then dereferences the invalid pointer, crashing the kernel.

Check the result of kthread_run() before passing it to kthread_stop(). Use

WARN_ON() so that a failure to create the self-test thread does not go

unnoticed, matching the ring-buffer self-test fix in commit

91542863abad ("ring-buffer: Fix crash passing ERR_PTR to kthread_stop()").