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.
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.
Published:
2026-09-04
Score:
n/a
EPSS:
n/a
KEV:
No
Impact:
n/a
Action:
n/a
No analysis available yet.
Remediation
No remediation available yet.
Tracking
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Advisories
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References
History
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 |
|
|
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
No data.
Weaknesses
No weakness.