drm: use after free in drm_queue_vblank_event()
The "e" pointer is either NULL or freed when we call
drm_vblank_put(dev, e->pipe) on the error path. Just pass the "pipe"
variable directly instead.
I changed another caller to use "pipe" as well for consistency.
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
index 722700d..16d5155 100644
--- a/drivers/gpu/drm/drm_irq.c
+++ b/drivers/gpu/drm/drm_irq.c
@@ -628,7 +628,7 @@
if ((seq - vblwait->request.sequence) <= (1 << 23)) {
e->event.tv_sec = now.tv_sec;
e->event.tv_usec = now.tv_usec;
- drm_vblank_put(dev, e->pipe);
+ drm_vblank_put(dev, pipe);
list_add_tail(&e->base.link, &e->base.file_priv->event_list);
wake_up_interruptible(&e->base.file_priv->event_wait);
trace_drm_vblank_event_delivered(current->pid, pipe,
@@ -645,7 +645,7 @@
spin_unlock_irqrestore(&dev->event_lock, flags);
kfree(e);
err_put:
- drm_vblank_put(dev, e->pipe);
+ drm_vblank_put(dev, pipe);
return ret;
}
