From: Srinivasan Shanmugam <srinivasan.shanmu...@amd.com>
[ Upstream commit ac2140449184a26eac99585b7f69814bd3ba8f2d ]
This commit addresses a potential null pointer dereference issue in the
`dcn32_acquire_idle_pipe_for_head_pipe_in_layer` function. The issue
could occur when `head_pipe` is null.
The fix adds a check to ensure `head_pipe` is not null before asserting
it. If `head_pipe` is null, the function returns NULL to prevent a
potential null pointer dereference.
Reported by smatch:
drivers/gpu/drm/amd/amdgpu/../display/dc/resource/dcn32/dcn32_resource.c:2690
dcn32_acquire_idle_pipe_for_head_pipe_in_layer() error: we previously assumed
'head_pipe' could be null (see line 2681)
Cc: Tom Chung <chiahsuan.ch...@amd.com>
Cc: Rodrigo Siqueira <rodrigo.sique...@amd.com>
Cc: Roman Li <roman...@amd.com>
Cc: Alex Hung <alex.h...@amd.com>
Cc: Aurabindo Pillai <aurabindo.pil...@amd.com>
Cc: Harry Wentland <harry.wentl...@amd.com>
Cc: Hamza Mahfooz <hamza.mahf...@amd.com>
Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmu...@amd.com>
Reviewed-by: Tom Chung <chiahsuan.ch...@amd.com>
Signed-off-by: Alex Deucher <alexander.deuc...@amd.com>
Signed-off-by: Sasha Levin <sas...@kernel.org>
---
.../gpu/drm/amd/display/dc/resource/dcn32/dcn32_resource.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/amd/display/dc/resource/dcn32/dcn32_resource.c
b/drivers/gpu/drm/amd/display/dc/resource/dcn32/dcn32_resource.c
index d84c8e0e5c2f0..9209bcad699a8 100644
--- a/drivers/gpu/drm/amd/display/dc/resource/dcn32/dcn32_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/resource/dcn32/dcn32_resource.c
@@ -2664,8 +2664,10 @@ static struct pipe_ctx
*dcn32_acquire_idle_pipe_for_head_pipe_in_layer(
struct resource_context *old_ctx =
&stream->ctx->dc->current_state->res_ctx;
int head_index;
- if (!head_pipe)
+ if (!head_pipe) {
ASSERT(0);
+ return NULL;
+ }
/*
* Modified from dcn20_acquire_idle_pipe_for_layer
--
2.43.0
