btrfs: fix ulist leaks in error paths of qgroup self tests
This is an automated ID intended to aid in discovery of potential security vulnerabilities. The actual impact and attack plausibility have not yet been proven. This ID is fixed in Linux Kernel version v4.19.265 by commit 203204798831c35d855ecc6417d98267d2d2184b, it was introduced in version v4.2 by commit 442244c9633292a147ab2b29e7007a7c8a3909b2. For more details please see the references link.