Service interruption via devlink double-locking
Published Sep 16, 2025 · Updated Sep 16, 2025
Improper locking in the Linux mlx5 driver allows local users to interrupt service through a devlink firmware activation. The synchronous-reset unload worker reenters an mlx5 unload path while the physical function already holds the devlink lock, producing a double-lock condition and a lockdep assertion. Triggering the condition requires local access to invoke devlink reload with the fw_activate action on an mlx5 physical function, an operation that can reset firmware and cause downtime.
Summary
What happened
Improper locking in the Linux mlx5 driver allows local users to interrupt service through a devlink firmware activation. The synchronous-reset unload worker reenters an mlx5 unload path while the physical function already holds the devlink lock, producing a double-lock condition and a lockdep assertion. Triggering the condition requires local access to invoke devlink reload with the fw_activate action on an mlx5 physical function, an operation that can reset firmware and cause downtime.
The record
- CVE
- CVE-2025-39832
- Published
- Sep 16, 2025
- Updated
- Sep 16, 2025
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- CWE-667, T1499
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Sep 16, 2025CVE publishedPublication date reported by the CVE source.
- Sep 16, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=6.5
- Affected versionversion=7a9770f1bfeaeddf5afabd3244e2c4c4966be37d <06d897148e79638651800d851a69547b56b4be2e
- Affected versionversion=7a9770f1bfeaeddf5afabd3244e2c4c4966be37d <0c87dba9ccd3801d3b503f0b4fd41be343af4f06
- Affected versionversion=7a9770f1bfeaeddf5afabd3244e2c4c4966be37d <902a8bc23a24882200f57cadc270e15a2cfaf2bb
- Affected versionversion=7a9770f1bfeaeddf5afabd3244e2c4c4966be37d <ddac9d0fe2493dd550cbfc75eeaf31e9b6dac959
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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