CVE-2021-47461

medium

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.

References

https://git.kernel.org/stable/c/cb185d5f1ebf900f4ae3bf84cee212e6dd035aca

https://git.kernel.org/stable/c/3cda4bfffd4f755645577aaa9e96a606657b4525

https://git.kernel.org/stable/c/149958ecd0627a9f1e9c678c25c665400054cd6a

Details

Source: Mitre, NVD

Published: 2024-05-22

Updated: 2024-05-22

Risk Information

CVSS v2

Base Score: 4.6

Vector: CVSS2#AV:L/AC:L/Au:S/C:N/I:N/A:C

Severity: Medium

CVSS v3

Base Score: 5.5

Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Severity: Medium