In the Linux kernel, the following vulnerability has been resolved: ntfs: avoid self-deadlock...

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

ntfs: avoid self-deadlock during inode eviction

An attribute-list update performed while allocating clusters can drop the last reference to the temporary attribute inode. Evicting that inode drops its reference to the base inode and can invoke ntfs_drop_big_inode() for the base inode from within the base inode's own writeback path.

If the base inode is unlinked, ntfs_drop_big_inode() calls truncate_setsize(), which waits for the inode's folio writeback to complete. The same writeback worker is responsible for completing that writeback, so it waits for itself indefinitely.

Prevent this self-deadlock by grabbing a reference to the base inode at the beginning of ntfs_writepages() and releasing it at the end of the function. This defers eviction until all bios have been submitted, allowing the wait for folio writeback to complete safely.