Reviewed-by: Tom Chung <[email protected]>
On 7/22/2024 9:46 AM, Srinivasan Shanmugam wrote:
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 <[email protected]>
Cc: Rodrigo Siqueira <[email protected]>
Cc: Roman Li <[email protected]>
Cc: Alex Hung <[email protected]>
Cc: Aurabindo Pillai <[email protected]>
Cc: Harry Wentland <[email protected]>
Cc: Hamza Mahfooz <[email protected]>
Signed-off-by: Srinivasan Shanmugam <[email protected]>
---
.../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 6eaf3cfebcb7..a124ad9bd108 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
@@ -2678,8 +2678,10 @@ 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
