| Name | CVE-2021-47461 |
| 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. |
| Source | CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|---|---|---|
| linux (PTS) | jessie, jessie (lts) | 3.16.84-1 | vulnerable |
| stretch (security) | 4.9.320-2 | vulnerable | |
| stretch (lts), stretch | 4.9.320-3 | vulnerable | |
| buster (security), buster, buster (lts) | 4.19.316-1 | fixed | |
| bullseye (security), bullseye | 5.10.223-1 | fixed | |
| bookworm | 6.1.106-3 | fixed | |
| bookworm (security) | 6.1.99-1 | fixed | |
| trixie | 6.10.6-1 | fixed | |
| sid | 6.10.7-1 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|---|---|---|---|---|---|
| linux | source | jessie | (unfixed) | end-of-life | ||
| linux | source | stretch | (unfixed) | end-of-life | ||
| linux | source | buster | (not affected) | |||
| linux | source | bullseye | 5.10.84-1 | |||
| linux | source | (unstable) | 5.14.16-1 |
[buster] - linux <not-affected> (Vulnerable code not present)
https://git.kernel.org/linus/cb185d5f1ebf900f4ae3bf84cee212e6dd035aca (5.15-rc7)