In the Linux kernel, the following vulnerability has been resolved:
perf: Fix sample vs do_exit()
Baisheng Gao reported an ARM64 crash, which Mark decoded as being a
synchronous external abort -- most likely due to trying to access
MMIO in bad ways.
The crash further shows perf trying to do a user stack sample while in
exit_mmap()'s tlb_finish_mmu() -- i.e. while tearing down the address
space it is trying to access.
It turns out that we stop perf after we tear down the userspace mm; a
receipie for disaster, since perf likes to access userspace for
various reasons.
Flip this order by moving up where we stop perf in do_exit().
Additionally, harden PERF_SAMPLE_CALLCHAIN and PERF_SAMPLE_STACK_USER
to abort when the current task does not have an mm (exit_mm() makes
sure to set current->mm = NULL; before commencing with the actual
teardown). Such that CPU wide events don't trip on this same problem.
References
Configurations
Configuration 1 (hide)
|
Configuration 2 (hide)
|
History
No history.
Information
Published : 2025-07-25 15:15
Updated : 2025-12-23 18:35
NVD link : CVE-2025-38424
Mitre link : CVE-2025-38424
CVE.ORG link : CVE-2025-38424
JSON object : View
Products Affected
debian
- debian_linux
linux
- linux_kernel
CWE
