In the Linux kernel, the following vulnerability has been resolved:
fuse: fix invalidate lock leak on open O_TRUNC DAX failure
fuse_open() takes filemap_invalidate_lock() for a DAX truncate
(dax_truncate = true) and releases it before the out_inode_unlock
label. But when fuse_dax_break_layouts() fails, the goto
out_inode_unlock skips the unlock and leaks the rwsem, so any later
fault or truncate on the file stalls on the stale lock.
fuse_dax_break_layouts() can fail with -ERESTARTSYS when a signal
interrupts the wait for busy DAX pages to drain:
open("file", O_RDWR | O_TRUNC)
└─ fuse_open()
├─ filemap_invalidate_lock() # dax_truncate
└─ fuse_dax_break_layouts()
└─ dax_break_layout()
└─ wait_page_idle() # TASK_INTERRUPTIBLE
└─ fuse_wait_dax_page() # unlock, schedule, re-lock
└─ signal → -ERESTARTSYS
goto out_inode_unlock # <- lock leaked
Fix this by moving filemap_invalidate_unlock() below the label so
that all error paths release the lock, and rename the label to
out_unlock as it now covers more than just the inode lock.
fuse: fix invalidate lock leak on open O_TRUNC DAX failure
fuse_open() takes filemap_invalidate_lock() for a DAX truncate
(dax_truncate = true) and releases it before the out_inode_unlock
label. But when fuse_dax_break_layouts() fails, the goto
out_inode_unlock skips the unlock and leaks the rwsem, so any later
fault or truncate on the file stalls on the stale lock.
fuse_dax_break_layouts() can fail with -ERESTARTSYS when a signal
interrupts the wait for busy DAX pages to drain:
open("file", O_RDWR | O_TRUNC)
└─ fuse_open()
├─ filemap_invalidate_lock() # dax_truncate
└─ fuse_dax_break_layouts()
└─ dax_break_layout()
└─ wait_page_idle() # TASK_INTERRUPTIBLE
└─ fuse_wait_dax_page() # unlock, schedule, re-lock
└─ signal → -ERESTARTSYS
goto out_inode_unlock # <- lock leaked
Fix this by moving filemap_invalidate_unlock() below the label so
that all error paths release the lock, and rename the label to
out_unlock as it now covers more than just the inode lock.
Advisories
No advisories yet.
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
Fri, 04 Sep 2026 19:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Weaknesses | CWE-668 |
Fri, 04 Sep 2026 16:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: fuse: fix invalidate lock leak on open O_TRUNC DAX failure fuse_open() takes filemap_invalidate_lock() for a DAX truncate (dax_truncate = true) and releases it before the out_inode_unlock label. But when fuse_dax_break_layouts() fails, the goto out_inode_unlock skips the unlock and leaks the rwsem, so any later fault or truncate on the file stalls on the stale lock. fuse_dax_break_layouts() can fail with -ERESTARTSYS when a signal interrupts the wait for busy DAX pages to drain: open("file", O_RDWR | O_TRUNC) └─ fuse_open() ├─ filemap_invalidate_lock() # dax_truncate └─ fuse_dax_break_layouts() └─ dax_break_layout() └─ wait_page_idle() # TASK_INTERRUPTIBLE └─ fuse_wait_dax_page() # unlock, schedule, re-lock └─ signal → -ERESTARTSYS goto out_inode_unlock # <- lock leaked Fix this by moving filemap_invalidate_unlock() below the label so that all error paths release the lock, and rename the label to out_unlock as it now covers more than just the inode lock. | |
| Title | fuse: fix invalidate lock leak on open O_TRUNC DAX failure | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
|
Projects
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Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-09-04T15:55:07.864Z
Reserved: 2026-08-26T14:34:25.797Z
Link: CVE-2026-80855
No data.
Status : Received
Published: 2026-09-04T16:18:14.507
Modified: 2026-09-04T16:18:14.507
Link: CVE-2026-80855
No data.
OpenCVE Enrichment
Updated: 2026-09-04T19:30:04Z
Weaknesses