CVE-2026-74572

Technical Description

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

btrfs: zoned: fix deadlock between metadata writeback and transaction commit

When writing out metadata extent buffers in a zoned filesystem,

btree_writepages() holds fs_info->zoned_meta_io_lock across the whole

writeback loop, including the call to btrfs_check_meta_write_pointer() ->

check_bg_is_active().

For the tree-log block group, check_bg_is_active() may fail to activate

the zone and fall back to btrfs_zone_finish_one_bg() to free an active

zone. That path waits for the running transaction to commit while still

holding zoned_meta_io_lock, but the committer needs that same lock to

write out the tree extents, so the two tasks deadlock:

Task A (kworker, metadata writeback) Task B (fsstress, transaction commit)

------------------------------------ -------------------------------------

wb_workfn() btrfs_commit_transaction(T)

btree_writepages()

Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

References