vhost: reject zero size iova range

We used to accept zero size iova range which will lead a infinite loop in translate_desc(). Fixing this by failing the request in this case. Reported-by: [email protected] Fixes: 6b1e6cc ("vhost: new device IOTLB API") Signed-off-by: Jason Wang <[email protected]> Acked-by: Michael S. Tsirkin <[email protected]> Signed-off-by: David S. Miller <[email protected]>
raspberrypi · Apr 11, 2019 · 813dbeb · 813dbeb
1 parent b4f47f3
commit 813dbeb
Showing 1 changed file with 5 additions and 1 deletion.
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
@@ -911,8 +911,12 @@ static int vhost_new_umem_range(struct vhost_umem *umem,
 				u64 start, u64 size, u64 end,
 				u64 userspace_addr, int perm)
 {
-	struct vhost_umem_node *tmp, *node = kmalloc(sizeof(*node), GFP_ATOMIC);
+	struct vhost_umem_node *tmp, *node;
 
+	if (!size)
+		return -EFAULT;
+
+	node = kmalloc(sizeof(*node), GFP_ATOMIC);
 	if (!node)
 		return -ENOMEM;