[Why]
resource_get_otg_master_for_stream() can return NULL if no OTG master pipe
is found for a given stream. The current code dereferences this pointer
without a NULL check. This may lead to a possible NULL pointer
dereference.
[How]
Add an explicit NULL check and skip the stream if the OTG master is not
found. This is similar to dcn60_update_clocks_update_dtb_dto().
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes: b6d508533fa1 ("drm/amd/display: fix a crash when clock source is
reference for non otg master pipe")
Signed-off-by: Roman Demidov <[email protected]>
---
drivers/gpu/drm/amd/display/dc/clk_mgr/dcn401/dcn401_clk_mgr.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn401/dcn401_clk_mgr.c
b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn401/dcn401_clk_mgr.c
index 6ee3da89d058..135eeef68ac4 100644
--- a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn401/dcn401_clk_mgr.c
+++ b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn401/dcn401_clk_mgr.c
@@ -538,6 +538,9 @@ static void dcn401_update_clocks_update_dtb_dto(struct
clk_mgr_internal *clk_mgr
otg_master = resource_get_otg_master_for_stream(
&context->res_ctx, context->streams[i]);
ASSERT(otg_master);
+ if (!otg_master)
+ continue;
+
ASSERT(otg_master->clock_source);
ASSERT(otg_master->clock_source->funcs->program_pix_clk);
ASSERT(otg_master->stream_res.pix_clk_params.controller_id >=
CONTROLLER_ID_D0);
--
2.53.0
