CVE-2026-64356xfs: fix memory leak in xfs_dqinode_metadir_create()

Official description

In the Linux kernel, the following vulnerability has been resolved: xfs: fix memory leak in xfs_dqinode_metadir_create() If xfs_metadir_create() fails in xfs_dqinode_metadir_create(), the current code returns directly, leaking the allocated update and transaction state. If the subsequent commit fails, the caller-owned inode reference is left behind. Fix this memory leak by routing the create failure path through xfs_metadir_cancel(). For both create and commit failures, finish and release any inode returned to the caller, mirroring the unwind pattern in xfs_metadir_mkdir(). The bug was first flagged by an experimental analysis tool we are developing for kernel memory-management bugs while analyzing v6.13-rc1. The tool is still under development and is not yet publicly available. Manual inspection confirms that the bug is still present in v7.1.1. An x86_64 allyesconfig build showed no new warnings. Runtime validation used kprobe fault injection during `mount -o uquota` on a metadir XFS image. Injecting xfs_metadir_create() reproduced the old active-update path that left mount stuck later in mount setup; after this change, the same injection reported cancel_hits=1 and irele_hits=1. Injecting xfs_metadir_commit() exercised the old inode-reference leak path; after this change, it reported irele_hits=1.

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/c3d3d2212c2966973dd7d603c6c6e6ed6fc7fbe1
• https://git.kernel.org/stable/c/06a2e6dbaa26c0740ac76dfa66b0aedc78d05820
• https://git.kernel.org/stable/c/45de375b25060edf46e20abb36521ba530336ceb