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

drm/amd/display: Add null check for head_pipe in dcn201_acquire_free_pipe_for_layer

This commit addresses a potential null pointer dereference issue in the
`dcn201_acquire_free_pipe_for_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/dcn201/dcn201_resource.c:1016 dcn201_acquire_free_pipe_for_layer() error: we previously assumed 'head_pipe' could be null (see line 1010)

kernel.org https://git.kernel.org/stable/c/390d757621f5f35d11a63ed7d9d3262ead240064 [No types assigned]

kernel.org https://git.kernel.org/stable/c/8a1b1655a490a492a5a6987254c935ecce4eb9de [No types assigned]

kernel.org https://git.kernel.org/stable/c/f22f4754aaa47d8c59f166ba3042182859e5dff7 [No types assigned]