The patch below does not apply to the 4.19-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
Thanks, Sasha
------------------ original commit in Linus's tree ------------------
From a8edc9cc0b14e3769bbc9b82d00e5e5fc6b5ff0a Mon Sep 17 00:00:00 2001 From: Roman Li roman.li@amd.com Date: Tue, 30 Jan 2024 18:07:24 -0500 Subject: [PATCH] drm/amd/display: Fix array-index-out-of-bounds in dcn35_clkmgr
[Why] There is a potential memory access violation while iterating through array of dcn35 clks.
[How] Limit iteration per array size.
Cc: Mario Limonciello mario.limonciello@amd.com Cc: Alex Deucher alexander.deucher@amd.com Cc: stable@vger.kernel.org Reviewed-by: Nicholas Kazlauskas nicholas.kazlauskas@amd.com Acked-by: Aurabindo Pillai aurabindo.pillai@amd.com Signed-off-by: Roman Li roman.li@amd.com Tested-by: Daniel Wheeler daniel.wheeler@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com --- .../amd/display/dc/clk_mgr/dcn35/dcn35_clk_mgr.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn35/dcn35_clk_mgr.c b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn35/dcn35_clk_mgr.c index 36e5bb611fb10..c378b879c76d8 100644 --- a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn35/dcn35_clk_mgr.c +++ b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn35/dcn35_clk_mgr.c @@ -658,10 +658,13 @@ static void dcn35_clk_mgr_helper_populate_bw_params(struct clk_mgr_internal *clk struct clk_limit_table_entry def_max = bw_params->clk_table.entries[bw_params->clk_table.num_entries - 1]; uint32_t max_fclk = 0, min_pstate = 0, max_dispclk = 0, max_dppclk = 0; uint32_t max_pstate = 0, max_dram_speed_mts = 0, min_dram_speed_mts = 0; + uint32_t num_memps, num_fclk, num_dcfclk; int i;
/* Determine min/max p-state values. */ - for (i = 0; i < clock_table->NumMemPstatesEnabled; i++) { + num_memps = (clock_table->NumMemPstatesEnabled > NUM_MEM_PSTATE_LEVELS) ? NUM_MEM_PSTATE_LEVELS : + clock_table->NumMemPstatesEnabled; + for (i = 0; i < num_memps; i++) { uint32_t dram_speed_mts = calc_dram_speed_mts(&clock_table->MemPstateTable[i]);
if (is_valid_clock_value(dram_speed_mts) && dram_speed_mts > max_dram_speed_mts) { @@ -673,7 +676,7 @@ static void dcn35_clk_mgr_helper_populate_bw_params(struct clk_mgr_internal *clk min_dram_speed_mts = max_dram_speed_mts; min_pstate = max_pstate;
- for (i = 0; i < clock_table->NumMemPstatesEnabled; i++) { + for (i = 0; i < num_memps; i++) { uint32_t dram_speed_mts = calc_dram_speed_mts(&clock_table->MemPstateTable[i]);
if (is_valid_clock_value(dram_speed_mts) && dram_speed_mts < min_dram_speed_mts) { @@ -702,9 +705,13 @@ static void dcn35_clk_mgr_helper_populate_bw_params(struct clk_mgr_internal *clk /* Base the clock table on dcfclk, need at least one entry regardless of pmfw table */ ASSERT(clock_table->NumDcfClkLevelsEnabled > 0);
- max_fclk = find_max_clk_value(clock_table->FclkClocks_Freq, clock_table->NumFclkLevelsEnabled); + num_fclk = (clock_table->NumFclkLevelsEnabled > NUM_FCLK_DPM_LEVELS) ? NUM_FCLK_DPM_LEVELS : + clock_table->NumFclkLevelsEnabled; + max_fclk = find_max_clk_value(clock_table->FclkClocks_Freq, num_fclk);
- for (i = 0; i < clock_table->NumDcfClkLevelsEnabled; i++) { + num_dcfclk = (clock_table->NumFclkLevelsEnabled > NUM_DCFCLK_DPM_LEVELS) ? NUM_DCFCLK_DPM_LEVELS : + clock_table->NumDcfClkLevelsEnabled; + for (i = 0; i < num_dcfclk; i++) { int j;
/* First search defaults for the clocks we don't read using closest lower or equal default dcfclk */