Executive brief
A resource leak was identified in the XFS file system component of the Linux kernel. This occurs when the system fails to properly release a reference to a Direct Access (DAX) device during certain error conditions. While primarily a technical stability issue, such leaks can eventually lead to system resource exhaustion if triggered repeatedly.
Technical details
A resource leak exists in the XFS file system's buffer target allocation logic. Specifically, in the `xfs_alloc_buftarg()` function within `fs/xfs/xfs_buf.c`, the error handling path fails to call `fs_put_dax()` to decrement the reference count of the DAX device. This vulnerability was introduced by the implementation of the `->notify_failure()` handler. An attacker or a failing system process could potentially trigger this error path to cause a slow exhaustion of kernel resources. The issue has been resolved by ensuring `fs_put_dax()` is called before freeing the buffer target structure.
Affected products
- Linux Linux kernel All versions prior to the fix in XFS component
Timeline
- 2026-05-27: disclosed: Initial publication of the CVE record
- 2026-05-27: patched: Fixes merged into various stable kernel branches
References
- https://git.kernel.org/stable/c/28a6c132b8c6e5eeefa889c4fb43d65b12989d48
- https://git.kernel.org/stable/c/29a7b2614357393b176ef06ba5bc3ff5afc8df69
- https://git.kernel.org/stable/c/5804cb507233ed767a83ac70527b2f6c4566ec75
- https://git.kernel.org/stable/c/5c293a1e1ef0f838772d20ae8afae4cbd87cd3f9
- https://git.kernel.org/stable/c/82fb9da6477d08bdab954dc7bc081a41f2f9cae6