Executive Summary

This vulnerability exists in the Linux kernel's AMD GPU driver (amdgpu). Specifically, it involves the handling of a user-provided value called doorbell_offset during the creation of a user queue.

The function amdgpu_userq_get_doorbell_index() passes this doorbell_offset to another function without checking if the value is within valid bounds. If an attacker provides an arbitrarily large doorbell_offset, it can cause the calculated doorbell index to fall outside the allocated doorbell buffer object (BO).

This out-of-bounds calculation can potentially corrupt kernel doorbell space, which is a critical area used for communication between the GPU and the kernel.

The fix involves validating that the doorbell_offset is within the doorbell BO before computing the BAR index, using 64-bit arithmetic to prevent overflow.

Useful 0 Not Useful 0

Impact Analysis

This vulnerability can lead to corruption of kernel memory related to the doorbell space, which is used for GPU and kernel communication.

Such corruption could potentially cause system instability, crashes, or allow an attacker to execute arbitrary code with kernel privileges.

Therefore, exploitation of this vulnerability could compromise the security and stability of a system running the affected Linux kernel with the AMD GPU driver.

Useful 0 Not Useful 0

Mitigation Strategies

The vulnerability in the Linux kernel related to the amdgpu driver involves improper validation of the doorbell_offset in user queue creation, which can lead to kernel doorbell space corruption.

To mitigate this vulnerability, you should update your Linux kernel to a version that includes the fix where doorbell_offset is validated before use, ensuring it falls within the doorbell BO and preventing overflow.

Useful 0 Not Useful 0