Reviewed-by: Tom Chung <chiahsuan.ch...@amd.com>
On 7/25/2024 10:54 AM, Srinivasan Shanmugam wrote:
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.ch...@amd.com> Cc: Rodrigo Siqueira <rodrigo.sique...@amd.com> Cc: Roman Li <roman...@amd.com> Cc: Alex Hung <alex.h...@amd.com> Cc: Aurabindo Pillai <aurabindo.pil...@amd.com> Cc: Harry Wentland <harry.wentl...@amd.com> Cc: Hamza Mahfooz <hamza.mahf...@amd.com> Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmu...@amd.com> --- .../amd/display/dc/hwss/dcn20/dcn20_hwseq.c | 30 ++++++++++++------- 1 file changed, 19 insertions(+), 11 deletions(-) diff --git a/drivers/gpu/drm/amd/display/dc/hwss/dcn20/dcn20_hwseq.c b/drivers/gpu/drm/amd/display/dc/hwss/dcn20/dcn20_hwseq.c index 270e337ae27b..5a6064999033 100644 --- a/drivers/gpu/drm/amd/display/dc/hwss/dcn20/dcn20_hwseq.c +++ b/drivers/gpu/drm/amd/display/dc/hwss/dcn20/dcn20_hwseq.c @@ -1922,22 +1922,29 @@ static void dcn20_program_pipe( dc->res_pool->hubbub, pipe_ctx->plane_res.hubp->inst, pipe_ctx->hubp_regs.det_size); }- 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 (hws->funcs.populate_mcm_luts) {- hws->funcs.populate_mcm_luts(dc, pipe_ctx, pipe_ctx->plane_state->mcm_luts, - pipe_ctx->plane_state->lut_bank_a); - pipe_ctx->plane_state->lut_bank_a = !pipe_ctx->plane_state->lut_bank_a; + if (pipe_ctx->plane_state) { + hws->funcs.populate_mcm_luts(dc, pipe_ctx, pipe_ctx->plane_state->mcm_luts, + pipe_ctx->plane_state->lut_bank_a); + pipe_ctx->plane_state->lut_bank_a = !pipe_ctx->plane_state->lut_bank_a; + } } 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@@ -1947,7 +1954,8 @@ 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@@ -1971,7 +1979,7 @@ 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,
