Bug 2492368 (CVE-2026-53063)

Summary: CVE-2026-53063 kernel: dm cache: fix write hang in passthrough mode
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
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Priority: low    
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 device-mapper (dm) cache component. Incomplete logic within the `invalidate_remove()` function, which handles write operations after cache invalidation, can lead to a system hang. This occurs because the function sets up remapping for write operations but fails to submit them, causing write operations to indefinitely wait for completion. This vulnerability could allow a local attacker to cause a Denial of Service (DoS) by triggering a write hang.
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Description OSIDB Bzimport 2026-06-24 18:08:15 UTC 
In the Linux kernel, the following vulnerability has been resolved:

dm cache: fix write hang in passthrough mode

The invalidate_remove() function has incomplete logic for handling write
hit bios after cache invalidation. It sets up the remapping for the
overwrite_bio but then drops it immediately without submission, causing
write operations to hang.

Fix by adding a new invalidate_committed() continuation that submits
the remapped writes to the cache origin after metadata commit completes,
while using the overwrite_endio hook to ensure proper completion
sequencing. This maintains existing coherency. Also improve error
handling in invalidate_complete() to preserve the original error status
instead of using bio_io_error() unconditionally.
Comment 1 Mauro Matteo Cascella 2026-06-26 16:23:11 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026062402-CVE-2026-53063-6abb@gregkh/T