ipv4: coding style: comparison for equality with NULL

The ipv4 code uses a mixture of coding styles. In some instances check
for NULL pointer is done as x == NULL and sometimes as !x. !x is
preferred according to checkpatch and this patch makes the code
consistent by adopting the latter form.

No changes detected by objdiff.

Signed-off-by: Ian Morris <ipm@chirality.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 652b92e..26a1cb3 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -1056,7 +1056,7 @@
 	__build_flow_key(&fl4, sk, iph, 0, 0, 0, 0, 0);
 
 	rt = (struct rtable *)odst;
-	if (odst->obsolete && odst->ops->check(odst, 0) == NULL) {
+	if (odst->obsolete && !odst->ops->check(odst, 0)) {
 		rt = ip_route_output_flow(sock_net(sk), &fl4, sk);
 		if (IS_ERR(rt))
 			goto out;
@@ -1450,7 +1450,7 @@
 
 	/* Primary sanity checks. */
 
-	if (in_dev == NULL)
+	if (!in_dev)
 		return -EINVAL;
 
 	if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr) ||
@@ -1553,7 +1553,7 @@
 
 	/* get a working reference to the output device */
 	out_dev = __in_dev_get_rcu(FIB_RES_DEV(*res));
-	if (out_dev == NULL) {
+	if (!out_dev) {
 		net_crit_ratelimited("Bug in ip_route_input_slow(). Please report.\n");
 		return -EINVAL;
 	}
@@ -2054,7 +2054,7 @@
 		     ipv4_is_lbcast(fl4->daddr))) {
 			/* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */
 			dev_out = __ip_dev_find(net, fl4->saddr, false);
-			if (dev_out == NULL)
+			if (!dev_out)
 				goto out;
 
 			/* Special hack: user can direct multicasts
@@ -2087,7 +2087,7 @@
 	if (fl4->flowi4_oif) {
 		dev_out = dev_get_by_index_rcu(net, fl4->flowi4_oif);
 		rth = ERR_PTR(-ENODEV);
-		if (dev_out == NULL)
+		if (!dev_out)
 			goto out;
 
 		/* RACE: Check return value of inet_select_addr instead. */
@@ -2299,7 +2299,7 @@
 	u32 metrics[RTAX_MAX];
 
 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*r), flags);
-	if (nlh == NULL)
+	if (!nlh)
 		return -EMSGSIZE;
 
 	r = nlmsg_data(nlh);
@@ -2421,7 +2421,7 @@
 	rtm = nlmsg_data(nlh);
 
 	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
-	if (skb == NULL) {
+	if (!skb) {
 		err = -ENOBUFS;
 		goto errout;
 	}
@@ -2452,7 +2452,7 @@
 		struct net_device *dev;
 
 		dev = __dev_get_by_index(net, iif);
-		if (dev == NULL) {
+		if (!dev) {
 			err = -ENODEV;
 			goto errout_free;
 		}
@@ -2651,7 +2651,7 @@
 	tbl = ipv4_route_flush_table;
 	if (!net_eq(net, &init_net)) {
 		tbl = kmemdup(tbl, sizeof(ipv4_route_flush_table), GFP_KERNEL);
-		if (tbl == NULL)
+		if (!tbl)
 			goto err_dup;
 
 		/* Don't export sysctls to unprivileged users */
@@ -2661,7 +2661,7 @@
 	tbl[0].extra1 = net;
 
 	net->ipv4.route_hdr = register_net_sysctl(net, "net/ipv4/route", tbl);
-	if (net->ipv4.route_hdr == NULL)
+	if (!net->ipv4.route_hdr)
 		goto err_reg;
 	return 0;