vulnerability
Red Hat: CVE-2021-47461: kernel: userfaultfd: fix a race between writeprotect and exit_mmap() (Multiple Advisories)
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 7 | (AV:L/AC:M/Au:S/C:C/I:C/A:C) | May 22, 2024 | Aug 12, 2024 | Mar 27, 2026 |
Severity
7
CVSS
(AV:L/AC:M/Au:S/C:C/I:C/A:C)
Published
May 22, 2024
Added
Aug 12, 2024
Modified
Mar 27, 2026
Description
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.
Solutions
redhat-upgrade-kernelredhat-upgrade-kernel-rt
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