From: Srinivasan Shanmugam <srinivasan.shanmugam@xxxxxxx>
commit f22f4754aaa47d8c59f166ba3042182859e5dff7 upstream.
This commit addresses a potential null pointer dereference issue in the
`dcn201_acquire_free_pipe_for_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/dcn201/dcn201_resource.c:1016 dcn201_acquire_free_pipe_for_layer() error: we previously assumed 'head_pipe' could be null (see line 1010)
Cc: Tom Chung <chiahsuan.chung@xxxxxxx>
Cc: Rodrigo Siqueira <Rodrigo.Siqueira@xxxxxxx>
Cc: Roman Li <roman.li@xxxxxxx>
Cc: Alex Hung <alex.hung@xxxxxxx>
Cc: Aurabindo Pillai <aurabindo.pillai@xxxxxxx>
Cc: Harry Wentland <harry.wentland@xxxxxxx>
Cc: Hamza Mahfooz <hamza.mahfooz@xxxxxxx>
Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmugam@xxxxxxx>
Reviewed-by: Tom Chung <chiahsuan.chung@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
[ dcn201 was moved from drivers/gpu/drm/amd/display/dc to
drivers/gpu/drm/amd/display/dc/resource since commit
8b8eed05a1c6 ("drm/amd/display: Refactor resource into component directory").
The path is changed accordingly to apply the patch on 6.6.y. ]
Signed-off-by: Xiangyu Chen <xiangyu.chen@xxxxxxxxxxxxx>
Signed-off-by: He Zhe <zhe.he@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/amd/display/dc/dcn201/dcn201_resource.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
--- a/drivers/gpu/drm/amd/display/dc/dcn201/dcn201_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn201/dcn201_resource.c
@@ -1002,8 +1002,10 @@ static struct pipe_ctx *dcn201_acquire_f
struct pipe_ctx *head_pipe = resource_get_otg_master_for_stream(res_ctx, opp_head_pipe->stream);
struct pipe_ctx *idle_pipe = resource_find_free_secondary_pipe_legacy(res_ctx, pool, head_pipe);
- if (!head_pipe)
+ if (!head_pipe) {
ASSERT(0);
+ return NULL;
+ }
if (!idle_pipe)
return NULL;
Patches currently in stable-queue which might be from srinivasan.shanmugam@xxxxxxx are
queue-6.6/drm-amd-display-add-null-check-for-head_pipe-in-dcn201_acquire_free_pipe_for_layer.patch
