From: Srinivasan Shanmugam <srinivasan.shanmugam@xxxxxxx> [ Upstream commit 8e4ed3cf1642df0c4456443d865cff61a9598aa8 ] This commit addresses a null pointer dereference issue in the `dcn20_program_pipe` function. The issue could occur when `pipe_ctx->plane_state` is null. The fix adds a check to ensure `pipe_ctx->plane_state` is not null before accessing. This prevents a null pointer dereference. Reported by smatch: drivers/gpu/drm/amd/amdgpu/../display/dc/hwss/dcn20/dcn20_hwseq.c:1925 dcn20_program_pipe() error: we previously assumed 'pipe_ctx->plane_state' could be null (see line 1877) 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> [Xiangyu: BP to fix CVE: CVE-2024-49914, modified the file path from drivers/gpu/drm/amd/amdgpu/../display/dc/hwss/dcn20/dcn20_hwseq.c to drivers/gpu/drm/amd/amdgpu/../display/dc/dcn20/dcn20_hwseq.c and minor conflict resolution] Signed-off-by: Xiangyu Chen <xiangyu.chen@xxxxxxxxxxxxx> --- .../drm/amd/display/dc/dcn20/dcn20_hwseq.c | 22 ++++++++++++------- 1 file changed, 14 insertions(+), 8 deletions(-) diff --git a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c index 12af2859002f..cd1d1b7283ab 100644 --- a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c +++ b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c @@ -1732,17 +1732,22 @@ static void dcn20_program_pipe( dc->res_pool->hubbub->funcs->program_det_size( dc->res_pool->hubbub, pipe_ctx->plane_res.hubp->inst, pipe_ctx->det_buffer_size_kb); - if (pipe_ctx->update_flags.raw || pipe_ctx->plane_state->update_flags.raw || pipe_ctx->stream->update_flags.raw) + if (pipe_ctx->update_flags.raw || + (pipe_ctx->plane_state && pipe_ctx->plane_state->update_flags.raw) || + pipe_ctx->stream->update_flags.raw) dcn20_update_dchubp_dpp(dc, pipe_ctx, context); - if (pipe_ctx->update_flags.bits.enable - || pipe_ctx->plane_state->update_flags.bits.hdr_mult) + if (pipe_ctx->update_flags.bits.enable || + (pipe_ctx->plane_state && pipe_ctx->plane_state->update_flags.bits.hdr_mult)) hws->funcs.set_hdr_multiplier(pipe_ctx); if (pipe_ctx->update_flags.bits.enable || - pipe_ctx->plane_state->update_flags.bits.in_transfer_func_change || - pipe_ctx->plane_state->update_flags.bits.gamma_change || - pipe_ctx->plane_state->update_flags.bits.lut_3d) + (pipe_ctx->plane_state && + pipe_ctx->plane_state->update_flags.bits.in_transfer_func_change) || + (pipe_ctx->plane_state && + pipe_ctx->plane_state->update_flags.bits.gamma_change) || + (pipe_ctx->plane_state && + pipe_ctx->plane_state->update_flags.bits.lut_3d)) hws->funcs.set_input_transfer_func(dc, pipe_ctx, pipe_ctx->plane_state); /* dcn10_translate_regamma_to_hw_format takes 750us to finish @@ -1752,7 +1757,8 @@ static void dcn20_program_pipe( if (pipe_ctx->update_flags.bits.enable || pipe_ctx->update_flags.bits.plane_changed || pipe_ctx->stream->update_flags.bits.out_tf || - pipe_ctx->plane_state->update_flags.bits.output_tf_change) + (pipe_ctx->plane_state && + pipe_ctx->plane_state->update_flags.bits.output_tf_change)) hws->funcs.set_output_transfer_func(dc, pipe_ctx, pipe_ctx->stream); /* If the pipe has been enabled or has a different opp, we @@ -1776,7 +1782,7 @@ static void dcn20_program_pipe( } /* Set ABM pipe after other pipe configurations done */ - if (pipe_ctx->plane_state->visible) { + if ((pipe_ctx->plane_state && pipe_ctx->plane_state->visible)) { if (pipe_ctx->stream_res.abm) { dc->hwss.set_pipe(pipe_ctx); pipe_ctx->stream_res.abm->funcs->set_abm_level(pipe_ctx->stream_res.abm, -- 2.43.0