drm/amd/display: Prevent potential buffer overflow in map_hw_resources
authorSrinivasan Shanmugam <srinivasan.shanmugam@amd.com>
Tue, 20 Feb 2024 03:44:25 +0000 (09:14 +0530)
committerAlex Deucher <alexander.deucher@amd.com>
Tue, 27 Feb 2024 17:20:42 +0000 (12:20 -0500)
commit0f8ca019544a252d1afb468ce840c6dcbac73af4
treed769de94fa920d295cc7b0f265edee8e27e69f8f
parentd206a76d7d2726f3b096037f2079ce0bd3ba329b
drm/amd/display: Prevent potential buffer overflow in map_hw_resources

Adds a check in the map_hw_resources function to prevent a potential
buffer overflow. The function was accessing arrays using an index that
could potentially be greater than the size of the arrays, leading to a
buffer overflow.

Adds a check to ensure that the index is within the bounds of the
arrays. If the index is out of bounds, an error message is printed and
break it will continue execution with just ignoring extra data early to
prevent the buffer overflow.

Reported by smatch:
drivers/gpu/drm/amd/amdgpu/../display/dc/dml2/dml2_wrapper.c:79 map_hw_resources() error: buffer overflow 'dml2->v20.scratch.dml_to_dc_pipe_mapping.disp_cfg_to_stream_id' 6 <= 7
drivers/gpu/drm/amd/amdgpu/../display/dc/dml2/dml2_wrapper.c:81 map_hw_resources() error: buffer overflow 'dml2->v20.scratch.dml_to_dc_pipe_mapping.disp_cfg_to_plane_id' 6 <= 7

Fixes: 7966f319c66d ("drm/amd/display: Introduce DML2")
Cc: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Cc: Roman Li <roman.li@amd.com>
Cc: Qingqing Zhuo <Qingqing.Zhuo@amd.com>
Cc: Aurabindo Pillai <aurabindo.pillai@amd.com>
Cc: Tom Chung <chiahsuan.chung@amd.com>
Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmugam@amd.com>
Suggested-by: Roman Li <roman.li@amd.com>
Reviewed-by: Roman Li <roman.li@amd.com>
Reviewed-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drivers/gpu/drm/amd/display/dc/dml2/dml2_wrapper.c