Bug 2516435 (CVE-2026-72187)

Summary: CVE-2026-72187 kernel: ntfs: avoid self-deadlock during inode eviction
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
Target Release: ---   
Hardware: All   
OS: Linux   
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A flaw was found in the Linux kernel's NTFS file system driver. An attacker with local access could trigger a self-deadlock condition during inode eviction. This occurs when an attribute-list update during cluster allocation causes a temporary inode to lose its last reference, leading to an indefinite wait during writeback. Successful exploitation of this vulnerability could result in a Denial of Service (DoS), causing the system to become unresponsive.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-08-15 06:12:22 UTC
In the Linux kernel, the following vulnerability has been resolved:

ntfs: avoid self-deadlock during inode eviction

An attribute-list update performed while allocating clusters can drop the
last reference to the temporary attribute inode. Evicting that inode
drops its reference to the base inode and can invoke ntfs_drop_big_inode()
for the base inode from within the base inode's own writeback path.

If the base inode is unlinked, ntfs_drop_big_inode() calls
truncate_setsize(), which waits for the inode's folio writeback to
complete. The same writeback worker is responsible for completing that
writeback, so it waits for itself indefinitely.

Prevent this self-deadlock by grabbing a reference to the base inode at the
beginning of ntfs_writepages() and releasing it at the end of the function.
This defers eviction until all bios have been submitted, allowing the wait
for folio writeback to complete safely.