[PATCH AUTOSEL 5.4 063/109] drm/display: fix possible null-pointer dereference in dcn10_set_clock()
From: Sasha Levin <sashal@kernel.org>
Date: 2021-09-09 13:42:56
Also in:
amd-gfx, dri-devel, stable
Subsystem:
amd display core, drm drivers, radeon and amdgpu drm drivers, the rest · Maintainers:
Harry Wentland, Leo Li, David Airlie, Simona Vetter, Alex Deucher, Christian König, Linus Torvalds
From: Tuo Li <redacted>
[ Upstream commit 554594567b1fa3da74f88ec7b2dc83d000c58e98 ]
The variable dc->clk_mgr is checked in:
if (dc->clk_mgr && dc->clk_mgr->funcs->get_clock)
This indicates dc->clk_mgr can be NULL.
However, it is dereferenced in:
if (!dc->clk_mgr->funcs->get_clock)
To fix this null-pointer dereference, check dc->clk_mgr and the function
pointer dc->clk_mgr->funcs->get_clock earlier, and return if one of them
is NULL.
Reported-by: TOTE Robot <redacted>
Signed-off-by: Tuo Li <redacted>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
.../gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c | 11 +++++------
1 file changed, 5 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c
index 60123db7ba02..bc5ebea1abed 100644
--- a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c@@ -3264,13 +3264,12 @@ static enum dc_status dcn10_set_clock(struct dc *dc, struct dc_clock_config clock_cfg = {0}; struct dc_clocks *current_clocks = &context->bw_ctx.bw.dcn.clk; - if (dc->clk_mgr && dc->clk_mgr->funcs->get_clock) - dc->clk_mgr->funcs->get_clock(dc->clk_mgr, - context, clock_type, &clock_cfg); - - if (!dc->clk_mgr->funcs->get_clock) + if (!dc->clk_mgr || !dc->clk_mgr->funcs->get_clock) return DC_FAIL_UNSUPPORTED_1; + dc->clk_mgr->funcs->get_clock(dc->clk_mgr, + context, clock_type, &clock_cfg); + if (clk_khz > clock_cfg.max_clock_khz) return DC_FAIL_CLK_EXCEED_MAX;
@@ -3288,7 +3287,7 @@ static enum dc_status dcn10_set_clock(struct dc *dc, else return DC_ERROR_UNEXPECTED; - if (dc->clk_mgr && dc->clk_mgr->funcs->update_clocks) + if (dc->clk_mgr->funcs->update_clocks) dc->clk_mgr->funcs->update_clocks(dc->clk_mgr, context, true); return DC_OK;
--
2.30.2