net: bridge: Use array_size() helper in copy_to_user()

[ Upstream commit 865bfb2 ]

Use array_size() helper instead of the open-coded version in
copy_to_user(). These sorts of multiplication factors need
to be wrapped in array_size().

Link: KSPP/linux#160
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

net/bridge/br_ioctl.c

@@ -71,7 +71,8 @@ static int get_fdb_entries(struct net_bridge *br, void __user *userbuf,
 
 	num = br_fdb_fillbuf(br, buf, maxnum, offset);
 	if (num > 0) {
-		if (copy_to_user(userbuf, buf, num*sizeof(struct __fdb_entry)))
+		if (copy_to_user(userbuf, buf,
+				 array_size(num, sizeof(struct __fdb_entry))))
 			num = -EFAULT;
 	}
 	kfree(buf);
@@ -188,7 +189,7 @@ int br_dev_siocdevprivate(struct net_device *dev, struct ifreq *rq, void __user
 			return -ENOMEM;
 
 		get_port_ifindices(br, indices, num);
-		if (copy_to_user(argp, indices, num * sizeof(int)))
+		if (copy_to_user(argp, indices, array_size(num, sizeof(int))))
 			num =  -EFAULT;
 		kfree(indices);
 		return num;
@@ -336,7 +337,8 @@ static int old_deviceless(struct net *net, void __user *uarg)
 
 		args[2] = get_bridge_ifindices(net, indices, args[2]);
 
-		ret = copy_to_user(uarg, indices, args[2]*sizeof(int))
+		ret = copy_to_user(uarg, indices,
+				   array_size(args[2], sizeof(int)))
 			? -EFAULT : args[2];
 
 		kfree(indices);