Vulnerability in drm/msm Package: Fix mmap to include VM_IO and VM_DONTDUMP

Background

The drm/msm package is a component of the Linux Kernel that provides support for graphics rendering on Qualcomm Adreno GPUs. It is responsible for managing the display and rendering capabilities of these GPUs. The package includes various functions and drivers that enable communication between the GPU and the operating system. One of the critical functions is mmap, which allows applications to map GPU memory into their address space for direct access.

However, a vulnerability has been discovered in the mmap function of the drm/msm package. This vulnerability affects versions of the Linux Kernel from v5.15 to v5.15.6. The vulnerability arises due to the omission of the VM_IO and VM_DONTDUMP flags when mapping GPU memory. This oversight can potentially lead to security issues and unauthorized access to sensitive data.

Vulnerability Detail

The vulnerability in the drm/msm package arises from the incorrect implementation of the mmap function. The function fails to include the VM_IO and VM_DONTDUMP flags when mapping GPU memory. These flags are essential for ensuring the security and integrity of the mapped memory. Without these flags, the mapped memory may be accessible to unauthorized entities and can be dumped, potentially exposing sensitive information.

An attacker exploiting this vulnerability could gain unauthorized access to GPU memory, potentially leading to the extraction of sensitive data or the execution of arbitrary code. The impact of this vulnerability depends on the specific use case and the sensitivity of the data stored in GPU memory.

It is important to note that the actual impact and attack plausibility of this vulnerability have not been proven yet.

Workaround

As a temporary workaround, it is recommended to avoid mapping GPU memory using the mmap function in the drm/msm package until the Linux Kernel is updated to a fixed version. This can be achieved by modifying the affected code to use alternative methods for accessing GPU memory or by disabling the functionality that relies on the mmap function.

Here is an example of a code modification that avoids using mmap:

// Original code
mmap(...); // Vulnerable function

// Modified code
alternative_function(...); // Alternative method

Conclusion

The vulnerability in the drm/msm package's mmap function poses a potential security risk by allowing unauthorized access to GPU memory. To mitigate this vulnerability, it is crucial to update the Linux Kernel to version v5.15.7 or later, which includes the necessary fix. Alternatively, a temporary workaround can be implemented by avoiding the use of the mmap function until the update is applied. For further assistance or support in addressing this vulnerability, please contact DevNack.com.

See every vulnerability recorded for Kernel →

FAQ