In the Linux kernel, the following vulnerability has been resolved:
mm/damon/dbgfs: protect targets destructions with kdamond_lock DAMON
debugfs interface iterates current monitoring targets in
‘dbgfs_target_ids_read()’ while holding the corresponding ‘kdamond_lock’.
However, it also destructs the monitoring targets in
‘dbgfs_before_terminate()’ without holding the lock. This can result in a
use_after_free bug. This commit avoids the race by protecting the
destruction with the corresponding ‘kdamond_lock’.
Author | Note |
---|---|
Priority reason: Exploitation requires write access to debugfs entries, which are restricted to root by default on Ubuntu kernels. |
git.kernel.org/linus/34796417964b8d0aef45a99cf6c2d20cebe33733 (5.16-rc7)
git.kernel.org/stable/c/330c6117a82c16a9a365a51cec5c9ab30b13245c
git.kernel.org/stable/c/34796417964b8d0aef45a99cf6c2d20cebe33733
launchpad.net/bugs/cve/CVE-2021-47088
nvd.nist.gov/vuln/detail/CVE-2021-47088
security-tracker.debian.org/tracker/CVE-2021-47088
www.cve.org/CVERecord?id=CVE-2021-47088