diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index 0856a13cb53d8001ff33f48cfd7e048721e476d2..8298e676f5a015f58d1b6005cf85938f8c8e142a 100644
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -1610,9 +1610,11 @@ static int packet_recvmsg(struct kiocb *iocb, struct socket *sock,
 
 		err = -EINVAL;
 		vnet_hdr_len = sizeof(vnet_hdr);
-		if ((len -= vnet_hdr_len) < 0)
+		if (len < vnet_hdr_len)
 			goto out_free;
 
+		len -= vnet_hdr_len;
+
 		if (skb_is_gso(skb)) {
 			struct skb_shared_info *sinfo = skb_shinfo(skb);