CVE-2026-31481 (GCVE-0-2026-31481)

Vulnerability from cvelistv5 – Published: 2026-04-22 13:54 – Updated: 2026-05-11 22:09
VLAI?
Title
tracing: Drain deferred trigger frees if kthread creation fails
Summary
In the Linux kernel, the following vulnerability has been resolved: tracing: Drain deferred trigger frees if kthread creation fails Boot-time trigger registration can fail before the trigger-data cleanup kthread exists. Deferring those frees until late init is fine, but the post-boot fallback must still drain the deferred list if kthread creation never succeeds. Otherwise, boot-deferred nodes can accumulate on trigger_data_free_list, later frees fall back to synchronously freeing only the current object, and the older queued entries are leaked forever. To trigger this, add the following to the kernel command line: trace_event=sched_switch trace_trigger=sched_switch.traceon,sched_switch.traceon The second traceon trigger will fail and be freed. This triggers a NULL pointer dereference and crashes the kernel. Keep the deferred boot-time behavior, but when kthread creation fails, drain the whole queued list synchronously. Do the same in the late-init drain path so queued entries are not stranded there either.
Severity ?
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 61d445af0a7c70018111919e47beaaee15653f2f , < 771624b7884a83bb9f922ae64ee41a5f8b7576c9 (git)
Affected: 61d445af0a7c70018111919e47beaaee15653f2f , < 250ab25391edeeab8462b68be42e4904506c409c (git)
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Linux Linux Affected: 6.19
Unaffected: 0 , < 6.19 (semver)
Unaffected: 6.19.11 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
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