CVE-2026-46058

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

media: amphion: Fix race between m2m job_abort and device_run

Fix kernel panic caused by race condition where v4l2_m2m_ctx_release() frees m2m_ctx while v4l2_m2m_try_run() is about to call device_run with the same context.

Race sequence: v4l2_m2m_try_run(): v4l2_m2m_ctx_release(): lock/unlock v4l2_m2m_cancel_job() job_abort() v4l2_m2m_job_finish() kfree(m2m_ctx) <- frees ctx device_run() <- use-after-free crash at 0x538

Crash trace: Unable to handle kernel read from unreadable memory at virtual address 0000000000000538 v4l2_m2m_try_run+0x78/0x138 v4l2_m2m_device_run_work+0x14/0x20

The amphion vpu driver does not rely on the m2m frameworks device_run callback to perform encode/decode operations.

Fix the race by preventing m2m framework job scheduling entirely:

• Add job_ready callback returning 0 (no jobs ready for m2m framework)
• Remove job_abort callback to avoid the race condition

Weakness

The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.

Affected Software

Extended Description

A race condition occurs within concurrent environments, and it is effectively a property of a code sequence. Depending on the context, a code sequence may be in the form of a function call, a small number of instructions, a series of program invocations, etc. A race condition violates these properties, which are closely related:

A race condition exists when an “interfering code sequence” can still access the shared resource, violating exclusivity. The interfering code sequence could be “trusted” or “untrusted.” A trusted interfering code sequence occurs within the product; it cannot be modified by the attacker, and it can only be invoked indirectly. An untrusted interfering code sequence can be authored directly by the attacker, and typically it is external to the vulnerable product.

Potential Mitigations

• Minimize the usage of shared resources in order to remove as much complexity as possible from the control flow and to reduce the likelihood of unexpected conditions occurring.
• Additionally, this will minimize the amount of synchronization necessary and may even help to reduce the likelihood of a denial of service where an attacker may be able to repeatedly trigger a critical section (CWE-400).

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/26.html
• https://cwe.mitre.org/data/definitions/29.html

References

• https://git.kernel.org/stable/c/42dc622776f3ce1a6c31b13bdc686f7295e3b323
• https://git.kernel.org/stable/c/516467052fdfc6a13eadc70d43420ae57436bf3c
• https://git.kernel.org/stable/c/6be2cb75bc1300080cfc8051579f22efae9401f7
• https://git.kernel.org/stable/c/8cd35ceadcfc8c5da2eb7f7ce24525ce9d4ee62e
• https://git.kernel.org/stable/c/da4f46c5cf1d26e6b09418ad453e152f2e75a02c
• https://git.kernel.org/stable/c/fdc150dac1adb9a98be9d6956cff0348838b024a