CVE-2026-90156 (GCVE-0-2026-90156)

Vulnerability from cvelistv5 – Published: 2026-09-17 16:06 – Updated: 2026-09-18 17:49
VLAI
Title
ksmbd: safely discard unregistered deferred locks
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.
Severity
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 , < d09af9a35ff7b77a950b507133d9092aadbfeff4 (git)
Affected: e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 , < 054bcca4cd9f00719b01f7108b51a2168fb94f15 (git)
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Linux Linux Affected: 5.15
Unaffected: 0 , < 5.15 (semver)
Unaffected: 7.2.6 , ≤ 7.2.* (semver)
Unaffected: 7.3-rc1 , ≤ * (original_commit_for_fix)
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            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: safely discard unregistered deferred locks\n\nWhen vfs_lock_file() defers a lock, smb2_lock() puts its ksmbd_lock on\nrollback_list before allocating and registering the asynchronous work.\nIf either operation fails, rollback assumes that smb_lock-\u003econn is\ninitialized and dereferences NULL. The deferred file_lock also remains\nlinked into the VFS blocked-lock state while it is freed.\n\nKeep the lock off rollback_list until async setup succeeds. On setup\nfailures, explicitly unblock and wake the deferred lock before freeing it\nand its ksmbd wrapper."
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}



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Nomenclature

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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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