5.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Srinivasan Shanmugam <srinivasan.shanmugam@xxxxxxx> [ Upstream commit 66d71a72539e173a9b00ca0b1852cbaa5f5bf1ad ] This commit addresses a null pointer dereference issue in the `commit_planes_for_stream` function at line 4140. The issue could occur when `top_pipe_to_program` is null. The fix adds a check to ensure `top_pipe_to_program` is not null before accessing its stream_res. This prevents a null pointer dereference. Reported by smatch: drivers/gpu/drm/amd/amdgpu/../display/dc/core/dc.c:4140 commit_planes_for_stream() error: we previously assumed 'top_pipe_to_program' could be null (see line 3906) 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> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/gpu/drm/amd/display/dc/core/dc.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/amd/display/dc/core/dc.c b/drivers/gpu/drm/amd/display/dc/core/dc.c index 272252cd05001..0587598009233 100644 --- a/drivers/gpu/drm/amd/display/dc/core/dc.c +++ b/drivers/gpu/drm/amd/display/dc/core/dc.c @@ -2614,7 +2614,8 @@ static void commit_planes_for_stream(struct dc *dc, dc->hwss.pipe_control_lock(dc, top_pipe_to_program, false); if ((update_type != UPDATE_TYPE_FAST) && stream->update_flags.bits.dsc_changed) - if (top_pipe_to_program->stream_res.tg->funcs->lock_doublebuffer_enable) { + if (top_pipe_to_program && + top_pipe_to_program->stream_res.tg->funcs->lock_doublebuffer_enable) { top_pipe_to_program->stream_res.tg->funcs->wait_for_state( top_pipe_to_program->stream_res.tg, CRTC_STATE_VACTIVE); -- 2.43.0