CVE-2024-57946

In the Linux kernel, the following vulnerability has been resolved:

virtio-blk: dont keep queue frozen during system suspend

Commit 4ce6e2db00de (virtio-blk: Ensure no requests in virtqueues before deleting vqs.) replaces queue quiesce with queue freeze in virtio-blks PM callbacks. And the motivation is to drain inflight IOs before suspending.

block layers queue freeze looks very handy, but it is also easy to cause deadlock, such as, any attempt to call into bio_queue_enter() may run into deadlock if the queue is frozen in current context. There are all kinds of ->suspend() called in suspend context, so keeping queue frozen in the whole suspend context isnt one good idea. And Marek reported lockdep warning[1] caused by virtio-blks freeze queue in virtblk_freeze().

[1] https://lore.kernel.org/linux-block/ca16370e-d646-4eee-b9cc-87277c89c43c@samsung.com/

Given the motivation is to drain in-flight IOs, it can be done by calling freeze & unfreeze, meantime restore to previous behavior by keeping queue quiesced during suspend.

Weakness

The product does not properly acquire or release a lock on a resource, leading to unexpected resource state changes and behaviors.

Affected Software

Extended Description

Locking is a type of synchronization behavior that ensures that multiple independently-operating processes or threads do not interfere with each other when accessing the same resource. All processes/threads are expected to follow the same steps for locking. If these steps are not followed precisely - or if no locking is done at all - then another process/thread could modify the shared resource in a way that is not visible or predictable to the original process. This can lead to data or memory corruption, denial of service, etc.

Potential Mitigations

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/25.html
• https://cwe.mitre.org/data/definitions/26.html
• https://cwe.mitre.org/data/definitions/27.html

References

• https://git.kernel.org/stable/c/12c0ddd6c551c1e438b087f874b4f1223a75f7ea
• https://git.kernel.org/stable/c/6dea8e3de59928974bf157dd0499d3958d744ae4
• https://git.kernel.org/stable/c/7678abee0867e6b7fb89aa40f6e9f575f755fb37
• https://git.kernel.org/stable/c/92d5139b91147ab372a17daf5dc27a5b9278e516
• https://git.kernel.org/stable/c/9ca428c6397abaa8c38f5c69133a2299e1efbbf2
• https://git.kernel.org/stable/c/9e323f856cf4963120e0e3892a84ef8bd764a0e4
• https://git.kernel.org/stable/c/d738f3215bb4f88911ff4579780a44960c8e0ca5
• https://lists.debian.org/debian-lts-announce/2025/03/msg00001.html
• https://lists.debian.org/debian-lts-announce/2025/03/msg00002.html