CVE-2026-68132

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description An issue exists where the emergency thaw worker can deadlock when handling frozen block devices. This occurs because the function do thaw all callback() calls bdev thaw() while holding the sb->s umount semaphore exclusively. If the block device was frozen via bdev freeze(), the process of dropping the last block layer freeze reference triggers fs bdev thaw(), which attempts to reacquire sb->s umount, resulting in a deadlock. Additionally, acquiring bd fsfreeze mutex while holding s umount inverts the established locking order, potentially leading to ABBA deadlocks during concurrent block-layer freezes. This condition can block subsequent unmount, freeze, or thaw operations for the affected filesystem and block device.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.