In the Linux kernel, the following vulnerability has been resolved:
ksmbd: vfs: fix race on m_flags in vfs_cache
ksmbd maintains delete-on-close and pending-delete state in
ksmbd_inode->m_flags. In vfs_cache.c this field is accessed under
inconsistent locking: some paths read and modify m_flags under
ci->m_lock while others do so without taking the lock at all.
Examples:
- ksmbd_query_inode_status() and __ksmbd_inode_close() use
ci->m_lock when checking or updating m_flags.
- ksmbd_inode_pending_delete(), ksmbd_set_inode_pending_delete(),
ksmbd_clear_inode_pending_delete() and ksmbd_fd_set_delete_on_close()
used to read and modify m_flags without ci->m_lock.
This creates a potential data race on m_flags when multiple threads
open, close and delete the same file concurrently. In the worst case
delete-on-close and pending-delete bits can be lost or observed in an
inconsistent state, leading to confusing delete semantics (files that
stay on disk after delete-on-close, or files that disappear while still
in use).
Fix it by:
- Making ksmbd_query_inode_status() look at m_flags under ci->m_lock
after dropping inode_hash_lock.
- Adding ci->m_lock protection to all helpers that read or modify
m_flags (ksmbd_inode_pending_delete(), ksmbd_set_inode_pending_delete(),
ksmbd_clear_inode_pending_delete(), ksmbd_fd_set_delete_on_close()).
- Keeping the existing ci->m_lock protection in __ksmbd_inode_close(),
and moving the actual unlink/xattr removal outside the lock.
This unifies the locking around m_flags and removes the data race while
preserving the existing delete-on-close behaviour.
ksmbd: vfs: fix race on m_flags in vfs_cache
ksmbd maintains delete-on-close and pending-delete state in
ksmbd_inode->m_flags. In vfs_cache.c this field is accessed under
inconsistent locking: some paths read and modify m_flags under
ci->m_lock while others do so without taking the lock at all.
Examples:
- ksmbd_query_inode_status() and __ksmbd_inode_close() use
ci->m_lock when checking or updating m_flags.
- ksmbd_inode_pending_delete(), ksmbd_set_inode_pending_delete(),
ksmbd_clear_inode_pending_delete() and ksmbd_fd_set_delete_on_close()
used to read and modify m_flags without ci->m_lock.
This creates a potential data race on m_flags when multiple threads
open, close and delete the same file concurrently. In the worst case
delete-on-close and pending-delete bits can be lost or observed in an
inconsistent state, leading to confusing delete semantics (files that
stay on disk after delete-on-close, or files that disappear while still
in use).
Fix it by:
- Making ksmbd_query_inode_status() look at m_flags under ci->m_lock
after dropping inode_hash_lock.
- Adding ci->m_lock protection to all helpers that read or modify
m_flags (ksmbd_inode_pending_delete(), ksmbd_set_inode_pending_delete(),
ksmbd_clear_inode_pending_delete(), ksmbd_fd_set_delete_on_close()).
- Keeping the existing ci->m_lock protection in __ksmbd_inode_close(),
and moving the actual unlink/xattr removal outside the lock.
This unifies the locking around m_flags and removes the data race while
preserving the existing delete-on-close behaviour.
Metrics
Affected Vendors & Products
Advisories
No advisories yet.
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
Tue, 13 Jan 2026 15:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: ksmbd: vfs: fix race on m_flags in vfs_cache ksmbd maintains delete-on-close and pending-delete state in ksmbd_inode->m_flags. In vfs_cache.c this field is accessed under inconsistent locking: some paths read and modify m_flags under ci->m_lock while others do so without taking the lock at all. Examples: - ksmbd_query_inode_status() and __ksmbd_inode_close() use ci->m_lock when checking or updating m_flags. - ksmbd_inode_pending_delete(), ksmbd_set_inode_pending_delete(), ksmbd_clear_inode_pending_delete() and ksmbd_fd_set_delete_on_close() used to read and modify m_flags without ci->m_lock. This creates a potential data race on m_flags when multiple threads open, close and delete the same file concurrently. In the worst case delete-on-close and pending-delete bits can be lost or observed in an inconsistent state, leading to confusing delete semantics (files that stay on disk after delete-on-close, or files that disappear while still in use). Fix it by: - Making ksmbd_query_inode_status() look at m_flags under ci->m_lock after dropping inode_hash_lock. - Adding ci->m_lock protection to all helpers that read or modify m_flags (ksmbd_inode_pending_delete(), ksmbd_set_inode_pending_delete(), ksmbd_clear_inode_pending_delete(), ksmbd_fd_set_delete_on_close()). - Keeping the existing ci->m_lock protection in __ksmbd_inode_close(), and moving the actual unlink/xattr removal outside the lock. This unifies the locking around m_flags and removes the data race while preserving the existing delete-on-close behaviour. | |
| Title | ksmbd: vfs: fix race on m_flags in vfs_cache | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
Projects
Sign in to view the affected projects.
MITRE
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-01-13T15:29:15.817Z
Reserved: 2025-12-24T10:30:51.047Z
Link: CVE-2025-68809
Vulnrichment
No data.
NVD
Status : Received
Published: 2026-01-13T16:16:03.080
Modified: 2026-01-13T16:16:03.080
Link: CVE-2025-68809
Redhat
No data.
OpenCVE Enrichment
No data.
Weaknesses
No weakness.