On 30/06/2023 04:19, Tuo Li wrote: > The variable crtc->state->event is often protected by the lock > crtc->dev->event_lock when is accessed. However, it is accessed as a > condition of an if statement in exynos_drm_crtc_atomic_disable() without > holding the lock: > > if (crtc->state->event && !crtc->state->active) > > However, if crtc->state->event is changed to NULL by another thread right > after the conditions of the if statement is checked to be true, a > null-pointer dereference can occur in drm_crtc_send_vblank_event(): > > e->pipe = pipe; > > To fix this possible null-pointer dereference caused by data race, the > spin lock coverage is extended to protect the if statement as well as the > function call to drm_crtc_send_vblank_event(). > > Reported-by: BassCheck <bass@xxxxxxxxxxx> > Signed-off-by: Tuo Li <islituo@xxxxxxxxx> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx> Best regards, Krzysztof
