From dddc0557e3a02499ce336b1e2e67f5afaecccc80 Mon Sep 17 00:00:00 2001 From: Nicholas Kazlauskas Date: Fri, 3 Aug 2018 10:40:20 -0400 Subject: [PATCH] drm/amd/display: Guard against null crtc in CRC IRQ [Why] A null pointer deference can occur if crtc is null in amdgpu_dm_crtc_handle_crc_irq. This can happen if get_crtc_by_otg_inst returns NULL during dm_crtc_high_irq, leading to a hang in some IGT test cases. [How] Check that CRTC is non-null before accessing its fields. Signed-off-by: Nicholas Kazlauskas Reviewed-by: Sun peng Li Acked-by: Leo Li Signed-off-by: Alex Deucher --- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crc.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crc.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crc.c index 52f2c01349e3..9bfb040352e9 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crc.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crc.c @@ -98,10 +98,16 @@ int amdgpu_dm_crtc_set_crc_source(struct drm_crtc *crtc, const char *src_name, */ void amdgpu_dm_crtc_handle_crc_irq(struct drm_crtc *crtc) { - struct dm_crtc_state *crtc_state = to_dm_crtc_state(crtc->state); - struct dc_stream_state *stream_state = crtc_state->stream; + struct dm_crtc_state *crtc_state; + struct dc_stream_state *stream_state; uint32_t crcs[3]; + if (crtc == NULL) + return; + + crtc_state = to_dm_crtc_state(crtc->state); + stream_state = crtc_state->stream; + /* Early return if CRC capture is not enabled. */ if (!crtc_state->crc_enabled) return; -- 2.11.0