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>
This commit is contained in:
Srinivasan Shanmugam 2024-02-20 09:14:25 +05:30 committed by Alex Deucher
parent d206a76d7d
commit 0f8ca01954

View File

@ -76,6 +76,11 @@ static void map_hw_resources(struct dml2_context *dml2,
in_out_display_cfg->hw.DLGRefClkFreqMHz = 50;
}
for (j = 0; j < mode_support_info->DPPPerSurface[i]; j++) {
if (i >= __DML2_WRAPPER_MAX_STREAMS_PLANES__) {
dml_print("DML::%s: Index out of bounds: i=%d, __DML2_WRAPPER_MAX_STREAMS_PLANES__=%d\n",
__func__, i, __DML2_WRAPPER_MAX_STREAMS_PLANES__);
break;
}
dml2->v20.scratch.dml_to_dc_pipe_mapping.dml_pipe_idx_to_stream_id[num_pipes] = dml2->v20.scratch.dml_to_dc_pipe_mapping.disp_cfg_to_stream_id[i];
dml2->v20.scratch.dml_to_dc_pipe_mapping.dml_pipe_idx_to_stream_id_valid[num_pipes] = true;
dml2->v20.scratch.dml_to_dc_pipe_mapping.dml_pipe_idx_to_plane_id[num_pipes] = dml2->v20.scratch.dml_to_dc_pipe_mapping.disp_cfg_to_plane_id[i];