vhost: reset metadata cache when initializing new IOTLB
We need to reset metadata cache during new IOTLB initialization,
otherwise the stale pointers to previous IOTLB may be still accessed
which will lead a use after free.
Reported-by: syzbot+c51e6736a1bf614b3272@syzkaller.appspotmail.com
Fixes: f88949138058 ("vhost: introduce O(1) vq metadata cache")
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index a502f1a..ed31145 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -1560,9 +1560,12 @@
d->iotlb = niotlb;
for (i = 0; i < d->nvqs; ++i) {
- mutex_lock(&d->vqs[i]->mutex);
- d->vqs[i]->iotlb = niotlb;
- mutex_unlock(&d->vqs[i]->mutex);
+ struct vhost_virtqueue *vq = d->vqs[i];
+
+ mutex_lock(&vq->mutex);
+ vq->iotlb = niotlb;
+ __vhost_vq_meta_reset(vq);
+ mutex_unlock(&vq->mutex);
}
vhost_umem_clean(oiotlb);
