CVE-2026-90156

Summary

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

ksmbd: safely discard unregistered deferred locks

When vfs_lock_file() defers a lock, smb2_lock() puts its ksmbd_lock on rollback_list before allocating and registering the asynchronous work. If either operation fails, rollback assumes that smb_lock->conn is initialized and dereferences NULL. The deferred file_lock also remains linked into the VFS blocked-lock state while it is freed.

Keep the lock off rollback_list until async setup succeeds. On setup failures, explicitly unblock and wake the deferred lock before freeing it and its ksmbd wrapper.

Affected Software

VendorProductVersion RangeStatus
LinuxLinuxe2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 < d09af9a35ff7b77a950b507133d9092aadbfeff4affected
LinuxLinuxe2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 < 054bcca4cd9f00719b01f7108b51a2168fb94f15affected
LinuxLinux5.15affected
LinuxLinux0 < 5.15unaffected
LinuxLinux7.2.6 <= 7.2.*unaffected
LinuxLinux7.3-rc1 <= *unaffected

Weaknesses

References