Bug 2516229 (CVE-2026-72190)

Summary: CVE-2026-72190 kernel: ntfs: fix mrec_lock ABBA deadlock in rename
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in the Linux kernel's NTFS filesystem driver. An incorrect locking order (ABBA deadlock) during file rename operations can lead to a race condition. A local attacker could exploit this by performing specific file system operations, causing the system to deadlock. This results in a Denial of Service (DoS), making the system unresponsive.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-08-15 06:01:37 UTC 
In the Linux kernel, the following vulnerability has been resolved:

ntfs: fix mrec_lock ABBA deadlock in rename

ntfs_file_fsync(), ntfs_dir_fsync() and __ntfs_write_inode() lock an
inode's mrec_lock before taking the mrec_lock of its parent directory.

ntfs_rename() takes old_ni->mrec_lock and old_dir_ni->mrec_lock
before taking new_ni->mrec_lock for an existing target, or
new_dir_ni->mrec_lock for a cross-directory rename.
This can deadlock when ntfs_file_fsync() or __ntfs_write_inode() holds
the target inode, or when ntfs_dir_fsync() holds a child target
directory, while rename() holds the parent directory and waits for the
target.

Fix this by locking the existing target inode before taking any parent
directory mrec_lock. For cross-directory renames where the target parent
is a descendant of the source parent, lock the target parent before the
source parent so the directory order matches the child-to-parent order used
by ntfs_file_fsync(), ntfs_dir_fsync(), and __ntfs_write_inode().
Comment 1 gkamathe 2026-08-17 10:21:29 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026081541-CVE-2026-72190-c8e9@gregkh/T