CVE-2026-74319

Summary

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

btrfs: zoned: fix deadlock waiting for ticket during data relocation

When performing data relocation on a zoned filesystem, BTRFS can deadlock in handle_reserve_tickets(). The relocation process is waiting on a space reservation ticket that can never be fulfilled, because the relocation itself is the operation responsible for freeing up that space.

Fix this by introducing a new flush state, BTRFS_RESERVE_FLUSH_ZONED_RELOCATION, specifically for data chunk allocation during zoned relocation. Like BTRFS_RESERVE_FLUSH_FREE_SPACE_INODE, this state uses priority_reclaim_data_space() instead of the normal flushing path, which avoids re-entering the relocation code and breaking the deadlock cycle.

In btrfs_alloc_data_chunk_ondemand(), select this new flush state when the inode belongs to a data relocation root on a zoned filesystem.

Affected Software

VendorProductVersion RangeStatus
LinuxLinuxe2a7fd22378f6500bcf979edc71e6837271eacfd < f84dbbaa988e1344634a20ddf6c7d51a99f12477affected
LinuxLinuxe2a7fd22378f6500bcf979edc71e6837271eacfd < 814c3b4ea357297c507158bceb07bcdc5fbe9808affected
LinuxLinux7.1affected
LinuxLinux0 < 7.1unaffected
LinuxLinux7.1.5 <= 7.1.*unaffected
LinuxLinux7.2 <= *unaffected

Weaknesses

References