diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index 8093e39..4fa2d75 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -1171,7 +1171,6 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile,
 	bool zerocopy = false;
 	int err;
 	u32 rxhash;
-	ssize_t n;
 
 	if (!(tun->dev->flags & IFF_UP))
 		return -EIO;
@@ -1181,8 +1180,7 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile,
 			return -EINVAL;
 		len -= sizeof(pi);
 
-		n = copy_from_iter(&pi, sizeof(pi), from);
-		if (n != sizeof(pi))
+		if (!copy_from_iter_full(&pi, sizeof(pi), from))
 			return -EFAULT;
 	}
 
@@ -1191,8 +1189,7 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile,
 			return -EINVAL;
 		len -= tun->vnet_hdr_sz;
 
-		n = copy_from_iter(&gso, sizeof(gso), from);
-		if (n != sizeof(gso))
+		if (!copy_from_iter_full(&gso, sizeof(gso), from))
 			return -EFAULT;
 
 		if ((gso.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&