CVE-2026-90167

Summary

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

ksmbd: serialize oplock close with pending break ownership

close may abort an in-flight oplock break while another breaker already holds an opinfo reference. Releasing pending_break wakes that waiter, but without serializing the close transition with bit acquisition it can become a new break owner through the test_and_set_bit() fast path. It can then overwrite OPLOCK_CLOSING with OPLOCK_ACK_WAIT and continue a break for a dying opinfo.

Make OPLOCK_CLOSING terminal once the opinfo is removed from the inode list. Serialize that transition, pending_break acquisition, and OPLOCK_ACK_WAIT setup with an opinfo state lock. A breaker which loses the race releases its ownership and returns -ENOENT. Explicitly wake pending_break waiters during close so they can observe the terminal state.

Also prevent ACK and timeout paths from replacing OPLOCK_CLOSING with OPLOCK_STATE_NONE.

Affected Software

VendorProductVersion RangeStatus
LinuxLinuxe2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 < 5f97bac88bfb333f426f01c118b8235e75af8d96affected
LinuxLinuxe2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 < b0148dc5625dbfd50596ac63c7487c12e8a8ab03affected
LinuxLinux5.15affected
LinuxLinux0 < 5.15unaffected
LinuxLinux7.2.6 <= 7.2.*unaffected
LinuxLinux7.3-rc1 <= *unaffected

Weaknesses

References