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| author | Thierry Reding <treding@nvidia.com> | 2015-08-12 17:00:30 +0200 |
|---|---|---|
| committer | Daniel Vetter <daniel.vetter@ffwll.ch> | 2015-08-12 17:39:47 +0200 |
| commit | 7d1de851632d013023cd7c89eb8664f62e5beb2c (patch) | |
| tree | d162a424ad975352f7005bd33b084ad7acae19fa /drivers/gpu/drm/drm_irq.c | |
| parent | 2a7d3d6d5ddbd202c09f228829cd03609a8efb23 (diff) | |
| download | lwn-7d1de851632d013023cd7c89eb8664f62e5beb2c.tar.gz lwn-7d1de851632d013023cd7c89eb8664f62e5beb2c.zip | |
drm/irq: Check for valid VBLANK before dereference
When accessing the array of per-CRTC VBLANK structures we must always
check that the index into the array is valid before dereferencing to
avoid crashing.
Signed-off-by: Thierry Reding <treding@nvidia.com>
[danvet: Squash in my own whitespace ocd fixup in drm_vblank_count.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Diffstat (limited to 'drivers/gpu/drm/drm_irq.c')
| -rw-r--r-- | drivers/gpu/drm/drm_irq.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c index 120a16fe15c2..f7c8b758059f 100644 --- a/drivers/gpu/drm/drm_irq.c +++ b/drivers/gpu/drm/drm_irq.c @@ -877,6 +877,7 @@ u32 drm_vblank_count(struct drm_device *dev, int crtc) if (WARN_ON(crtc >= dev->num_crtcs)) return 0; + return vblank->count; } EXPORT_SYMBOL(drm_vblank_count); @@ -1110,10 +1111,10 @@ void drm_vblank_put(struct drm_device *dev, int crtc) { struct drm_vblank_crtc *vblank = &dev->vblank[crtc]; - if (WARN_ON(atomic_read(&vblank->refcount) == 0)) + if (WARN_ON(crtc >= dev->num_crtcs)) return; - if (WARN_ON(crtc >= dev->num_crtcs)) + if (WARN_ON(atomic_read(&vblank->refcount) == 0)) return; /* Last user schedules interrupt disable */ @@ -1158,6 +1159,9 @@ void drm_wait_one_vblank(struct drm_device *dev, int crtc) int ret; u32 last; + if (WARN_ON(crtc >= dev->num_crtcs)) + return; + ret = drm_vblank_get(dev, crtc); if (WARN(ret, "vblank not available on crtc %i, ret=%i\n", crtc, ret)) return; @@ -1428,6 +1432,9 @@ void drm_vblank_post_modeset(struct drm_device *dev, int crtc) if (!dev->num_crtcs) return; + if (WARN_ON(crtc >= dev->num_crtcs)) + return; + if (vblank->inmodeset) { spin_lock_irqsave(&dev->vbl_lock, irqflags); dev->vblank_disable_allowed = true; |