A race condition flaw was found in get_old_root in fs/btrfs/ctree.c in the Linux kernel in btrfs file-system. This flaw allows a local attacker with a special user privilege to cause a denial of service due to not locking an extent buffer before a cloning operation. The highest threat from this vulnerability is to system availability.
Reference and upstream patch:
Created kernel tracking bugs for this issue:
Affects: fedora-all [bug 1941805]
Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
This issue affected Linux kernel versions as shipped with Red Hat Enterprise Linux 7 / 7-RT.