tcp: remove redundant checks II

For same reasons than in commit 12e25e10 ("tcp: remove redundant
checks"), we can remove redundant checks done for timewait sockets.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/ipv4/tcp_ipv4.c

@@ -1671,10 +1671,6 @@ int tcp_v4_rcv(struct sk_buff *skb)
 		goto discard_it;
 	}
 
-	if (skb->len < (th->doff << 2)) {
-		inet_twsk_put(inet_twsk(sk));
-		goto bad_packet;
-	}
 	if (tcp_checksum_complete(skb)) {
 		inet_twsk_put(inet_twsk(sk));
 		goto csum_error;

net/ipv6/tcp_ipv6.c

@@ -1467,10 +1467,6 @@ static int tcp_v6_rcv(struct sk_buff *skb)
 
 	tcp_v6_fill_cb(skb, hdr, th);
 
-	if (skb->len < (th->doff<<2)) {
-		inet_twsk_put(inet_twsk(sk));
-		goto bad_packet;
-	}
 	if (tcp_checksum_complete(skb)) {
 		inet_twsk_put(inet_twsk(sk));
 		goto csum_error;