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>
Mon, 26 Feb 2024 16:12:54 +0000 (11:12 -0500)
commit34b811a281bab42d09592fdaa6885f4f41352bd3
treef36197c65ea085bb122181b39fe432e0749348b7
parentf435b5156bfae242ea59fd52d0291c0dec6bbfd2
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