CVE-2021-47461 (GCVE-0-2021-47461)
Vulnerability from cvelistv5
Published
2024-05-22 06:23
Modified
2025-05-04 07:11
Severity ?
Summary
In the Linux kernel, the following vulnerability has been resolved: userfaultfd: fix a race between writeprotect and exit_mmap() A race is possible when a process exits, its VMAs are removed by exit_mmap() and at the same time userfaultfd_writeprotect() is called. The race was detected by KASAN on a development kernel, but it appears to be possible on vanilla kernels as well. Use mmget_not_zero() to prevent the race as done in other userfaultfd operations.
References
Impacted products
Vendor Product Version
Linux Linux Version: 63b2d4174c4ad1f40b48d7138e71bcb564c1fe03
Version: 63b2d4174c4ad1f40b48d7138e71bcb564c1fe03
Version: 63b2d4174c4ad1f40b48d7138e71bcb564c1fe03
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