From: Wayne Lin <wayne.lin@xxxxxxx> [ Upstream commit b1904ed480cee3f9f4036ea0e36d139cb5fee2d6 ] [Why & How] Check whether assigned timing generator is NULL or not before accessing its funcs to prevent NULL dereference. Reviewed-by: Jun Lei <jun.lei@xxxxxxx> Acked-by: Hersen Wu <hersenxs.wu@xxxxxxx> Signed-off-by: Wayne Lin <wayne.lin@xxxxxxx> Tested-by: Daniel Wheeler <daniel.wheeler@xxxxxxx> Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/gpu/drm/amd/display/dc/core/dc_stream.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_stream.c b/drivers/gpu/drm/amd/display/dc/core/dc_stream.c index 01fe2d2fd2417..ebe571fcefe32 100644 --- a/drivers/gpu/drm/amd/display/dc/core/dc_stream.c +++ b/drivers/gpu/drm/amd/display/dc/core/dc_stream.c @@ -582,7 +582,7 @@ uint32_t dc_stream_get_vblank_counter(const struct dc_stream_state *stream) for (i = 0; i < MAX_PIPES; i++) { struct timing_generator *tg = res_ctx->pipe_ctx[i].stream_res.tg; - if (res_ctx->pipe_ctx[i].stream != stream) + if (res_ctx->pipe_ctx[i].stream != stream || !tg) continue; return tg->funcs->get_frame_count(tg); @@ -641,7 +641,7 @@ bool dc_stream_get_scanoutpos(const struct dc_stream_state *stream, for (i = 0; i < MAX_PIPES; i++) { struct timing_generator *tg = res_ctx->pipe_ctx[i].stream_res.tg; - if (res_ctx->pipe_ctx[i].stream != stream) + if (res_ctx->pipe_ctx[i].stream != stream || !tg) continue; tg->funcs->get_scanoutpos(tg, -- 2.42.0