ksmbd: detach blocked lock requests before freeing
A file_lock retained by ksmbd for byte-range lock bookkeeping can still
be part of the VFS blocked-request graph. In particular, the VFS can
chain a new waiter below an already blocked request through
flc_blocked_requests. The ksmbd_file reference count does not cover that
graph.
Both __ksmbd_close_fd() and the cross-request unlock path free these
retained file_lock objects directly. If a dependent waiter is still
attached, locks_release_private() hits
BUG_ON(!list_empty(&flc->flc_blocked_requests)). The same lifetime
mismatch can leave a freed ksmbd_lock reachable through its request-local
llist.
Detach the file_lock from the blocked-request graph before freeing it in
the close, cross-request unlock, and rollback paths. locks_delete_block()
also wakes requests chained below the object. Remove llist when a
completed lock is published so a globally visible ksmbd_lock no longer
points into the submitting worker's stack.
Analysis
Analysis and contextual insights are available on OpenCVE Cloud.
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Linux | Linux | unaffected |
|
|||||||||||||||
| Linux | Linux | affected |
|
No data.
No data.
No data available yet.
No vendor fix or workaround currently provided.
Additional remediation guidance may be available on OpenCVE Cloud.
Tracking
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Thu, 17 Sep 2026 16:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: ksmbd: detach blocked lock requests before freeing A file_lock retained by ksmbd for byte-range lock bookkeeping can still be part of the VFS blocked-request graph. In particular, the VFS can chain a new waiter below an already blocked request through flc_blocked_requests. The ksmbd_file reference count does not cover that graph. Both __ksmbd_close_fd() and the cross-request unlock path free these retained file_lock objects directly. If a dependent waiter is still attached, locks_release_private() hits BUG_ON(!list_empty(&flc->flc_blocked_requests)). The same lifetime mismatch can leave a freed ksmbd_lock reachable through its request-local llist. Detach the file_lock from the blocked-request graph before freeing it in the close, cross-request unlock, and rollback paths. locks_delete_block() also wakes requests chained below the object. Remove llist when a completed lock is published so a globally visible ksmbd_lock no longer points into the submitting worker's stack. | |
| Title | ksmbd: detach blocked lock requests before freeing | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
MITRE
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-09-17T16:06:47.716Z
Reserved: 2026-09-11T19:38:34.790Z
Link: CVE-2026-90155
Vulnrichment
No data.
NVD
Status : Received
Published: 2026-09-17T17:17:08.607
Modified: 2026-09-17T17:17:08.607
Link: CVE-2026-90155
Redhat
No data.
OpenCVE Enrichment
No data.
No weakness.