CVE-2026-53123: md: wake raid456 reshape waiters before suspend
In the Linux kernel, the following vulnerability has been resolved:
md: wake raid456 reshape waiters before suspend
During raid456 reshape, direct IO across the reshape position can sleep in raid5makerequest() waiting for reshape progress while still holding an activeio reference. If userspace then freezes reshape and writes md/suspendlo or md/suspendhi, mddevsuspend() kills activeio and waits for all in-flight IO to drain.
This can deadlock: the IO needs reshape progress to continue, but the reshape thread is already frozen, so the activeio reference is never dropped and suspend never completes.
raid5preparesuspend() already wakes waitforreshape for dm-raid. Do the same for normal md suspend when reshape is already interrupted, so waiting raid456 IO can abort, drop its reference, and let suspend finish.
The mdadm test tests/25raid456-reshape-deadlock reproduces the hang.
Affected Software
Remediation
Event History
Frequently Asked Questions
What is the severity of CVE-2026-53123?
The severity of CVE-2026-53123 is rated at 22, indicating a significant risk.
How do I fix CVE-2026-53123?
To fix CVE-2026-53123, users should update to the patched version of the Linux kernel as provided in the latest release.
What systems are affected by CVE-2026-53123?
CVE-2026-53123 affects systems running the vulnerable versions of the Linux kernel that utilize raid456.
What is the impact of CVE-2026-53123?
CVE-2026-53123 can lead to system instability during raid456 reshape operations if direct I/O actions are initiated.
When was CVE-2026-53123 published?
CVE-2026-53123 was published on June 24, 2026.