CVE-2026-98924 — fs: avoid repeated scans in evict_inodes()

Affected: Linux

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

fs: avoid repeated scans in evict_inodes()

We observed hung tasks when users attempted to unmount a filesystem after its disk had been removed while still in use. During device removal, fs_bdev_mark_dead() calls evict_inodes() while holding s_umount.

Each time evict_inodes() drops s_inode_list_lock to reschedule, it restarts the walk from the head of s_inodes. With many referenced inodes at the head of the list, these restarts repeatedly scan the same inodes without reclaiming them. This can keep s_umount held for a long time, blocking concurrent umount attempts and triggering hung-task reports.

Keep the current inode, already marked I_FREEING, out of the disposal batch until s_inode_list_lock is reacquired. Resume the walk from this inode and dispose of it in a later batch or at the end of the walk.

The zero-refcount and state checks under i_lock allow this walker to claim the inode by setting I_FREEING and removing it from the LRU. Other reclaimers skip the inode, leaving this walker responsible for eviction. Only evict() removes it from s_inodes, so keeping it out of the disposal batch ensures that it remains on the list while the lock is dropped. After reacquiring the lock, reading its current next pointer accounts for concurrent removal of following inodes.

The existing inode lifetime rules prohibit acquiring a reference to an inode marked I_FREEING or I_WILL_FREE. __iget() requires its caller to…

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CVE-2026-98924 — fs: avoid repeated scans in evict_inodes()