CVE-2025-38564

Description

In the Linux kernel, the following vulnerability has been resolved:perf/core: Handle buffer mapping fail correctly in perf_mmap()After successful allocation of a buffer or a successful attachment to anexisting buffer perf_mmap() tries to map the buffer read only into the pagetable. If that fails, the already set up page table entries are zapped, butthe other perf specific side effects of that failure are not handled. Thecalling code just cleans up the VMA and does not invoke perf_mmap_close().This leaks reference counts, corrupts user->vm accounting and also resultsin an unbalanced invocation of event::event_mapped().Cure this by moving the event::event_mapped() invocation before themap_range() call so that on map_range() failure perf_mmap_close() can beinvoked without causing an unbalanced event::event_unmapped() call.perf_mmap_close() undoes the reference counts and eventually frees buffers.

Risk Information

Associated Vulnerability

Patch Details

References

https://nvd.nist.gov/vuln/detail/CVE-2023-1234
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-1234