CVE-2024-49918

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

drm/amd/display: Add null check for headpipe in dcn32acquireidlepipeforheadpipein_layer

This commit addresses a potential null pointer dereference issue in the dcn32_acquire_idle_pipe_for_head_pipe_in_layer function. The issue could occur when head_pipe is null.

The fix adds a check to ensure head_pipe is not null before asserting it. If head_pipe is null, the function returns NULL to prevent a potential null pointer dereference.

Reported by smatch: drivers/gpu/drm/amd/amdgpu/../display/dc/resource/dcn32/dcn32resource.c:2690 dcn32acquireidlepipeforheadpipeinlayer() error: we previously assumed 'headpipe' could be null (see line 2681)