CVE-2026-80855

CVE Details

Release Date:	2026-09-04
Impact:	Moderate	What is this?

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.

See more information about CVE-2026-80855 from MITRE CVE dictionary and NIST NVD

NOTE: The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v3 metrics

Base Score:	3.3
Vector String:	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
Version:	3.1
Attack Vector:	Local
Attack Complexity:	Low
Privileges Required:	Low
User Interaction:	None
Scope:	Unchanged
Confidentiality Impact:	None
Integrity Impact:	None
Availability Impact:	Low

Errata information

Platform	Errata	Release Date
Oracle Linux version 8 (kernel-uek)	ELSA-2026-500377	2026-10-07
Oracle Linux version 9 (kernel-uek)	ELSA-2026-500374	2026-10-07
Oracle Linux version 9 (kernel-uek)	ELSA-2026-500377	2026-10-07