diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index 2e69b8d..bdc8073 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -565,7 +565,7 @@
 	opts->mss = tcp_advertise_mss(sk);
 	remaining -= TCPOLEN_MSS_ALIGNED;
 
-	if (likely(sysctl_tcp_timestamps && *md5 == NULL)) {
+	if (likely(sysctl_tcp_timestamps && !*md5)) {
 		opts->options |= OPTION_TS;
 		opts->tsval = tcp_skb_timestamp(skb) + tp->tsoffset;
 		opts->tsecr = tp->rx_opt.ts_recent;
@@ -1148,7 +1148,7 @@
 
 	/* Get a new skb... force flag on. */
 	buff = sk_stream_alloc_skb(sk, nsize, gfp);
-	if (buff == NULL)
+	if (!buff)
 		return -ENOMEM; /* We'll just try again later. */
 
 	sk->sk_wmem_queued += buff->truesize;
@@ -1707,7 +1707,7 @@
 		return tcp_fragment(sk, skb, len, mss_now, gfp);
 
 	buff = sk_stream_alloc_skb(sk, 0, gfp);
-	if (unlikely(buff == NULL))
+	if (unlikely(!buff))
 		return -ENOMEM;
 
 	sk->sk_wmem_queued += buff->truesize;
@@ -1925,7 +1925,8 @@
 	}
 
 	/* We're allowed to probe.  Build it now. */
-	if ((nskb = sk_stream_alloc_skb(sk, probe_size, GFP_ATOMIC)) == NULL)
+	nskb = sk_stream_alloc_skb(sk, probe_size, GFP_ATOMIC);
+	if (!nskb)
 		return -1;
 	sk->sk_wmem_queued += nskb->truesize;
 	sk_mem_charge(sk, nskb->truesize);
@@ -2733,7 +2734,7 @@
 		if (skb == tcp_send_head(sk))
 			break;
 		/* we could do better than to assign each time */
-		if (hole == NULL)
+		if (!hole)
 			tp->retransmit_skb_hint = skb;
 
 		/* Assume this retransmit will generate
@@ -2765,7 +2766,7 @@
 			goto begin_fwd;
 
 		} else if (!(sacked & TCPCB_LOST)) {
-			if (hole == NULL && !(sacked & (TCPCB_SACKED_RETRANS|TCPCB_SACKED_ACKED)))
+			if (!hole && !(sacked & (TCPCB_SACKED_RETRANS|TCPCB_SACKED_ACKED)))
 				hole = skb;
 			continue;
 
@@ -2868,14 +2869,14 @@
 	struct sk_buff *skb;
 
 	skb = tcp_write_queue_head(sk);
-	if (skb == NULL || !(TCP_SKB_CB(skb)->tcp_flags & TCPHDR_SYN)) {
+	if (!skb || !(TCP_SKB_CB(skb)->tcp_flags & TCPHDR_SYN)) {
 		pr_debug("%s: wrong queue state\n", __func__);
 		return -EFAULT;
 	}
 	if (!(TCP_SKB_CB(skb)->tcp_flags & TCPHDR_ACK)) {
 		if (skb_cloned(skb)) {
 			struct sk_buff *nskb = skb_copy(skb, GFP_ATOMIC);
-			if (nskb == NULL)
+			if (!nskb)
 				return -ENOMEM;
 			tcp_unlink_write_queue(skb, sk);
 			__skb_header_release(nskb);
@@ -3300,7 +3301,7 @@
 	 * sock.
 	 */
 	buff = alloc_skb(MAX_TCP_HEADER, sk_gfp_atomic(sk, GFP_ATOMIC));
-	if (buff == NULL) {
+	if (!buff) {
 		inet_csk_schedule_ack(sk);
 		inet_csk(sk)->icsk_ack.ato = TCP_ATO_MIN;
 		inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK,
@@ -3344,7 +3345,7 @@
 
 	/* We don't queue it, tcp_transmit_skb() sets ownership. */
 	skb = alloc_skb(MAX_TCP_HEADER, sk_gfp_atomic(sk, GFP_ATOMIC));
-	if (skb == NULL)
+	if (!skb)
 		return -1;
 
 	/* Reserve space for headers and set control bits. */