CVE-2024-43904

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

drm/amd/display: Add null checks for stream and plane before dereferencing

This commit adds null checks for the stream and plane variables in the dcn30_apply_idle_power_optimizations function. These variables were previously assumed to be null at line 922, but they were used later in the code without checking if they were null. This could potentially lead to a null pointer dereference, which would cause a crash.

The null checks ensure that stream and plane are not null before they are used, preventing potential crashes.

Fixes the below static smatch checker: drivers/gpu/drm/amd/amdgpu/../display/dc/hwss/dcn30/dcn30_hwseq.c:938 dcn30_apply_idle_power_optimizations() error: we previously assumed stream could be null (see line 922) drivers/gpu/drm/amd/amdgpu/../display/dc/hwss/dcn30/dcn30_hwseq.c:940 dcn30_apply_idle_power_optimizations() error: we previously assumed plane could be null (see line 922)

Weakness

A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit.

Affected Software

Potential Mitigations

References

• https://git.kernel.org/stable/c/10c20d79d59cadfe572480d98cec271a89ffb024
• https://git.kernel.org/stable/c/15c2990e0f0108b9c3752d7072a97d45d4283aea
• https://git.kernel.org/stable/c/16a8a2a839d19c4cf7253642b493ffb8eee1d857
• https://git.kernel.org/stable/c/5e84eda48ffb2363437db44bbd0235594f8a58f9