Circular Lock Dependency in Linux Kernel's ext4 Filesystem

CVE-2026-93269

What is CVE-2026-93269?

This vulnerability in the Linux kernel's ext4 filesystem involves a circular lock dependency that can lead to system deadlocks. Specifically, during the execution of ext4_ext_migrate and the orphan cleanup process, an order of operations leads to a situation where the system is unable to progress due to blocked locks. The temporary inode used in the migration process is meant for building the extent tree, where its eviction doesn't necessitate s_writepages_rwsem protection. By moving the iput() call after releasing the write semaphore, the potential for a deadlock is eliminated, enhancing overall system stability.

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