5.4-stable review patch. If anyone has any objections, please let me know.
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From: Alex Hung alex.hung@amd.com
[ Upstream commit b38a4815f79b87efb196cd5121579fc51e29a7fb ]
[WHY & HOW] num_valid_sets needs to be checked to avoid a negative index when accessing reader_wm_sets[num_valid_sets - 1].
This fixes an OVERRUN issue reported by Coverity.
Reviewed-by: Harry Wentland harry.wentland@amd.com Acked-by: Tom Chung chiahsuan.chung@amd.com Signed-off-by: Alex Hung alex.hung@amd.com Tested-by: Daniel Wheeler daniel.wheeler@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/amd/display/dc/clk_mgr/dcn21/rn_clk_mgr.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn21/rn_clk_mgr.c b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn21/rn_clk_mgr.c index 9f301f8575a5..fec3ca955b26 100644 --- a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn21/rn_clk_mgr.c +++ b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn21/rn_clk_mgr.c @@ -453,7 +453,8 @@ void build_watermark_ranges(struct clk_bw_params *bw_params, struct pp_smu_wm_ra ranges->reader_wm_sets[num_valid_sets].max_fill_clk_mhz = PP_SMU_WM_SET_RANGE_CLK_UNCONSTRAINED_MAX;
/* Modify previous watermark range to cover up to max */ - ranges->reader_wm_sets[num_valid_sets - 1].max_fill_clk_mhz = PP_SMU_WM_SET_RANGE_CLK_UNCONSTRAINED_MAX; + if (num_valid_sets > 0) + ranges->reader_wm_sets[num_valid_sets - 1].max_fill_clk_mhz = PP_SMU_WM_SET_RANGE_CLK_UNCONSTRAINED_MAX; } num_valid_sets++; }