5.15-stable review patch. If anyone has any objections, please let me know.
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From: Srinivasan Shanmugam srinivasan.shanmugam@amd.com
[ 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@amd.com Cc: Rodrigo Siqueira Rodrigo.Siqueira@amd.com Cc: Roman Li roman.li@amd.com Cc: Alex Hung alex.hung@amd.com Cc: Aurabindo Pillai aurabindo.pillai@amd.com Cc: Harry Wentland harry.wentland@amd.com Cc: Hamza Mahfooz hamza.mahfooz@amd.com Signed-off-by: Srinivasan Shanmugam srinivasan.shanmugam@amd.com Reviewed-by: Tom Chung chiahsuan.chung@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.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 12e4beca5e840..22dbc6bc21af4 100644 --- a/drivers/gpu/drm/amd/display/dc/core/dc.c +++ b/drivers/gpu/drm/amd/display/dc/core/dc.c @@ -3027,7 +3027,8 @@ 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);