In the Linux kernel, the following vulnerability has been resolved:
perf: Fix perf_pending_task() UaF
Per syzbot it is possible for perf_pending_task() to run after the
event is free()'d. There are two related but distinct cases:
- the task_work was already queued before destroying the event;
- destroying the event itself queues the task_work.
The first cannot be solved using task_work_cancel() since
perf_release() itself might be called from a task_work (____fput),
which means the current->task_works list is already empty and
task_work_cancel() won't be able to find the perf_pending_task()
entry.
The simplest alternative is extending the perf_event lifetime to cover
the task_work.
The second is just silly, queueing a task_work while you know the
event is going away makes no sense and is easily avoided by
re-arranging how the event is marked STATE_DEAD and ensuring it goes
through STATE_OFF on the way down.
References
Configurations
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History
No history.
Information
Published : 2024-10-21 20:15
Updated : 2024-10-25 20:02
NVD link : CVE-2022-48950
Mitre link : CVE-2022-48950
CVE.ORG link : CVE-2022-48950
JSON object : View
Products Affected
linux
- linux_kernel
CWE
CWE-416
Use After Free