Linux Kernel up to 6.12.16/6.13.4/6.14-rc3 spin_lock_irqsave deadlock

Summaryinfo

A vulnerability categorized as critical has been discovered in Linux Kernel up to 6.12.16/6.13.4/6.14-rc3. Impacted is the function spin_lock_irqsave. Executing a manipulation can lead to deadlock. The identification of this vulnerability is CVE-2025-21849. There is no exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability has been found in Linux Kernel up to 6.12.16/6.13.4/6.14-rc3 and classified as critical. This vulnerability affects the function spin_lock_irqsave. The manipulation with an unknown input leads to a deadlock vulnerability. The CWE definition for the vulnerability is CWE-833. The product contains multiple threads or executable segments that are waiting for each other to release a necessary lock, resulting in deadlock. As an impact it is known to affect availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: drm/i915/gt: Use spin_lock_irqsave() in interruptible context spin_lock/unlock() functions used in interrupt contexts could result in a deadlock, as seen in GitLab issue #13399, which occurs when interrupt comes in while holding a lock. Try to remedy the problem by saving irq state before spin lock acquisition. v2: add irqs' state save/restore calls to all locks/unlocks in signal_irq_work() execution (Maciej) v3: use with spin_lock_irqsave() in guc_lrc_desc_unpin() instead of other lock/unlock calls and add Fixes and Cc tags (Tvrtko); change title and commit message (cherry picked from commit c088387ddd6482b40f21ccf23db1125e8fa4af7e)

The advisory is shared for download at git.kernel.org. This vulnerability was named CVE-2025-21849 since 12/29/2024. The exploitation appears to be difficult. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 236983 (Ubuntu 24.04 LTS / 24.10 : Linux kernel vulnerabilities (USN-7521-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.12.17, 6.13.5 or 6.14-rc4 eliminates this vulnerability. Applying the patch 2bf1f4c129db7a10920655b000f0292f1ee509c2/47ae46ac5407646420e06b78e0dad331e56a4bb4/e49477f7f78598295551d486ecc7f020d796432e is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (236983) and CERT Bund (WID-SEC-2025-0545). Once again VulDB remains the best source for vulnerability data.

Affected

• Google Container-Optimized OS
• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• Siemens SIMATIC S7
• RESF Rocky Linux
• SolarWinds Security Event Manager
• Open Source Linux Kernel

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.12.0
• 6.12.1
• 6.12.2
• 6.12.3
• 6.12.4
• 6.12.5
• 6.12.6
• 6.12.7
• 6.12.8
• 6.12.9
• 6.12.10
• 6.12.11
• 6.12.12
• 6.12.13
• 6.12.14
• 6.12.15
• 6.12.16
• 6.13.0
• 6.13.1
• 6.13.2
• 6.13.3
• 6.13.4
• 6.14-rc1
• 6.14-rc2
• 6.14-rc3

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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Entryinfo

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