In the Linux kernel, the following vulnerability has been resolved: netfs, afs: Fix write skipping in dir/link writepages Fix netfs_write_single() and afs_single_writepages() to better handle a write that would be skipped due to lock contention and WB_SYNC_NONE by returning 1 from netfs_write_single() if it skipped and making afs_single_writepages() skip also. If a skip occurs, the inode must be re-marked as the VFS may have cleared the mark. This is really only theoretical for directories in netfs_write_single() as the only path to that is through afs_single_writepages() that takes the ->validate_lock around it, thereby serialising it.
https://git.kernel.org/stable/c/f91e10435c0dd37c48b1b25e6236284f656ddc0c
https://git.kernel.org/stable/c/9871938f99cc6cb266a77265491660e2375271f5
https://git.kernel.org/stable/c/77bb293049d61e04c12b24ebbffafaf5ab36af90