Vulnerability CVE-2024-41078
Published: 2024-07-29

Description:
In the Linux kernel, the following vulnerability has been resolved:

btrfs: qgroup: fix quota root leak after quota disable failure

If during the quota disable we fail when cleaning the quota tree or when
deleting the root from the root tree, we jump to the 'out' label without
ever dropping the reference on the quota root, resulting in a leak of the
root since fs_info->quota_root is no longer pointing to the root (we have
set it to NULL just before those steps).

Fix this by always doing a btrfs_put_root() call under the 'out' label.
This is a problem that exists since qgroups were first added in 2012 by
commit bed92eae26cc ("Btrfs: qgroup implementation and prototypes"), but
back then we missed a kfree on the quota root and free_extent_buffer()
calls on its root and commit root nodes, since back then roots were not
yet reference counted.

 References:
https://git.kernel.org/stable/c/94818bdb00ef34a996a06aa63d11f591074cb757
https://git.kernel.org/stable/c/8a69529f22590b67bb018de9acbcf94abc8603cf
https://git.kernel.org/stable/c/5ef3961682e5310f2221bae99bcf9f5d0f4b0d51
https://git.kernel.org/stable/c/f88aeff5a173e8ba3133314eb4b964236ef3589d
https://git.kernel.org/stable/c/7dd6a5b96157a21245566b21fd58276a214357ff
https://git.kernel.org/stable/c/a7e4c6a3031c74078dba7fa36239d0f4fe476c53
Copyright 2026, cxsecurity.com

 

Back to Top