5.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Wayne Lin wayne.lin@amd.com
[ 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@amd.com Acked-by: Hersen Wu hersenxs.wu@amd.com Signed-off-by: Wayne Lin wayne.lin@amd.com Tested-by: Daniel Wheeler daniel.wheeler@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Sasha Levin sashal@kernel.org --- 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 bb09243758fe3..71b10b45a9b9e 100644 --- a/drivers/gpu/drm/amd/display/dc/core/dc_stream.c +++ b/drivers/gpu/drm/amd/display/dc/core/dc_stream.c @@ -492,7 +492,7 @@ 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); @@ -551,7 +551,7 @@ 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,