CVE-2026-31481
Gravedad:
Pendiente de análisis
Tipo:
No Disponible / Otro tipo
Fecha de publicación:
22/04/2026
Última modificación:
23/04/2026
Descripción
*** Pendiente de traducción *** In the Linux kernel, the following vulnerability has been resolved:<br />
<br />
tracing: Drain deferred trigger frees if kthread creation fails<br />
<br />
Boot-time trigger registration can fail before the trigger-data cleanup<br />
kthread exists. Deferring those frees until late init is fine, but the<br />
post-boot fallback must still drain the deferred list if kthread<br />
creation never succeeds.<br />
<br />
Otherwise, boot-deferred nodes can accumulate on<br />
trigger_data_free_list, later frees fall back to synchronously freeing<br />
only the current object, and the older queued entries are leaked<br />
forever.<br />
<br />
To trigger this, add the following to the kernel command line:<br />
<br />
trace_event=sched_switch trace_trigger=sched_switch.traceon,sched_switch.traceon<br />
<br />
The second traceon trigger will fail and be freed. This triggers a NULL<br />
pointer dereference and crashes the kernel.<br />
<br />
Keep the deferred boot-time behavior, but when kthread creation fails,<br />
drain the whole queued list synchronously. Do the same in the late-init<br />
drain path so queued entries are not stranded there either.



