Total vulnerabilities in the database
In the Linux kernel, the following vulnerability has been resolved:
drm/mediatek: Fix a null pointer crash in mtk_drm_crtc_finish_page_flip
It's possible that mtk_crtc->event is NULL in mtk_drm_crtc_finish_page_flip().
pending_needs_vblank value is set by mtk_crtc->event, but in mtk_drm_crtc_atomic_flush(), it's is not guarded by the same lock in mtk_drm_finish_page_flip(), thus a race condition happens.
Consider the following case:
CPU1 CPU2 step 1: mtk_drm_crtc_atomic_begin() mtk_crtc->event is not null, step 1: mtk_drm_crtc_atomic_flush: mtk_drm_crtc_update_config( !!mtk_crtc->event) step 2: mtk_crtc_ddp_irq -> mtk_drm_finish_page_flip: lock mtk_crtc->event set to null, pending_needs_vblank set to false unlock pending_needs_vblank set to true,
step 2:
mtk_crtc_ddp_irq ->
mtk_drm_finish_page_flip called again,
pending_needs_vblank is still true
//null pointer
Instead of guarding the entire mtk_drm_crtc_atomic_flush(), it's more efficient to just check if mtk_crtc->event is null before use.
| Software | From | Fixed in |
|---|---|---|
| linux / linux_kernel | 6.7 | 6.7.11 |
| linux / linux_kernel | 6.2 | 6.6.23 |
| linux / linux_kernel | 5.16 | 6.1.83 |
| linux / linux_kernel | 5.11 | 5.15.153 |
| linux / linux_kernel | 5.5 | 5.10.214 |
| linux / linux_kernel | 4.20 | 5.4.273 |
| linux / linux_kernel | 4.7 | 4.19.311 |
| linux / linux_kernel | 6.8 | 6.8.2 |
| debian / debian_linux | 10.0 | 10.0.x |