--- zzzz-none-000/linux-2.6.39.4/net/ipv6/ip6mr.c	2011-08-03 19:43:28.000000000 +0000
+++ puma6-atom-6490-729/linux-2.6.39.4/net/ipv6/ip6mr.c	2021-11-10 13:38:18.000000000 +0000
@@ -169,7 +169,7 @@
 	}
 
 	mrt = ip6mr_get_table(rule->fr_net, rule->table);
-	if (mrt == NULL)
+	if (!mrt)
 		return -EAGAIN;
 	res->mrt = mrt;
 	return 0;
@@ -233,7 +233,7 @@
 	INIT_LIST_HEAD(&net->ipv6.mr6_tables);
 
 	mrt = ip6mr_new_table(net, RT6_TABLE_DFLT);
-	if (mrt == NULL) {
+	if (!mrt) {
 		err = -ENOMEM;
 		goto err1;
 	}
@@ -296,11 +296,11 @@
 	unsigned int i;
 
 	mrt = ip6mr_get_table(net, id);
-	if (mrt != NULL)
+	if (mrt)
 		return mrt;
 
 	mrt = kzalloc(sizeof(*mrt), GFP_KERNEL);
-	if (mrt == NULL)
+	if (!mrt)
 		return NULL;
 	mrt->id = id;
 	write_pnet(&mrt->net, net);
@@ -399,7 +399,7 @@
 	struct mr6_table *mrt;
 
 	mrt = ip6mr_get_table(net, RT6_TABLE_DFLT);
-	if (mrt == NULL)
+	if (!mrt)
 		return ERR_PTR(-ENOENT);
 
 	iter->mrt = mrt;
@@ -483,7 +483,7 @@
 	struct mr6_table *mrt;
 
 	mrt = ip6mr_get_table(net, RT6_TABLE_DFLT);
-	if (mrt == NULL)
+	if (!mrt)
 		return ERR_PTR(-ENOENT);
 
 	it->mrt = mrt;
@@ -656,7 +656,7 @@
 		dev_hold(reg_dev);
 	read_unlock(&mrt_lock);
 
-	if (reg_dev == NULL)
+	if (!reg_dev)
 		goto drop;
 
 	skb->mac_header = skb->network_header;
@@ -733,7 +733,7 @@
 		sprintf(name, "pim6reg%u", mrt->id);
 
 	dev = alloc_netdev(0, name, reg_vif_setup);
-	if (dev == NULL)
+	if (!dev)
 		return NULL;
 
 	dev_net_set(dev, net);
@@ -1009,7 +1009,7 @@
 static struct mfc6_cache *ip6mr_cache_alloc(void)
 {
 	struct mfc6_cache *c = kmem_cache_zalloc(mrt_cachep, GFP_KERNEL);
-	if (c == NULL)
+	if (!c)
 		return NULL;
 	c->mfc_un.res.minvif = MAXMIFS;
 	return c;
@@ -1018,7 +1018,7 @@
 static struct mfc6_cache *ip6mr_cache_alloc_unres(void)
 {
 	struct mfc6_cache *c = kmem_cache_zalloc(mrt_cachep, GFP_ATOMIC);
-	if (c == NULL)
+	if (!c)
 		return NULL;
 	skb_queue_head_init(&c->mfc_un.unres.unresolved);
 	c->mfc_un.unres.expires = jiffies + 10 * HZ;
@@ -1135,7 +1135,7 @@
 	skb->ip_summed = CHECKSUM_UNNECESSARY;
 	}
 
-	if (mrt->mroute6_sk == NULL) {
+	if (!mrt->mroute6_sk) {
 		kfree_skb(skb);
 		return -EINVAL;
 	}
@@ -1179,7 +1179,7 @@
 		 */
 
 		if (atomic_read(&mrt->cache_resolve_queue_len) >= 10 ||
-		    (c = ip6mr_cache_alloc_unres()) == NULL) {
+		    !(c = ip6mr_cache_alloc_unres())) {
 			spin_unlock_bh(&mfc_unres_lock);
 
 			kfree_skb(skb);
@@ -1417,7 +1417,7 @@
 		return -EINVAL;
 
 	c = ip6mr_cache_alloc();
-	if (c == NULL)
+	if (!c)
 		return -ENOMEM;
 
 	c->mf6c_origin = mfc->mf6cc_origin.sin6_addr;
@@ -1508,7 +1508,7 @@
 
 	rtnl_lock();
 	write_lock_bh(&mrt_lock);
-	if (likely(mrt->mroute6_sk == NULL)) {
+	if (likely(!mrt->mroute6_sk)) {
 		mrt->mroute6_sk = sk;
 		net->ipv6.devconf_all->mc_forwarding++;
 	}
@@ -1577,7 +1577,7 @@
 	struct mr6_table *mrt;
 
 	mrt = ip6mr_get_table(net, raw6_sk(sk)->ip6mr_table ? : RT6_TABLE_DFLT);
-	if (mrt == NULL)
+	if (!mrt)
 		return -ENOENT;
 
 	if (optname != MRT6_INIT) {
@@ -1711,7 +1711,7 @@
 	struct mr6_table *mrt;
 
 	mrt = ip6mr_get_table(net, raw6_sk(sk)->ip6mr_table ? : RT6_TABLE_DFLT);
-	if (mrt == NULL)
+	if (!mrt)
 		return -ENOENT;
 
 	switch (optname) {
@@ -1758,7 +1758,7 @@
 	struct mr6_table *mrt;
 
 	mrt = ip6mr_get_table(net, raw6_sk(sk)->ip6mr_table ? : RT6_TABLE_DFLT);
-	if (mrt == NULL)
+	if (!mrt)
 		return -ENOENT;
 
 	switch (cmd) {
@@ -1832,7 +1832,7 @@
 	struct mr6_table *mrt;
 
 	mrt = ip6mr_get_table(net, raw6_sk(sk)->ip6mr_table ? : RT6_TABLE_DFLT);
-	if (mrt == NULL)
+	if (!mrt)
 		return -ENOENT;
 
 	switch (cmd) {
@@ -1900,7 +1900,7 @@
 	struct dst_entry *dst;
 	struct flowi6 fl6;
 
-	if (vif->dev == NULL)
+	if (!vif->dev)
 		goto out_free;
 
 #ifdef CONFIG_IPV6_PIMSM_V2
@@ -2061,7 +2061,7 @@
 	/*
 	 *	No usable cache entry
 	 */
-	if (cache == NULL) {
+	if (!cache) {
 		int vif;
 
 		vif = ip6mr_find_vif(mrt, skb->dev);
@@ -2131,7 +2131,7 @@
 	struct rt6_info *rt = (struct rt6_info *)skb_dst(skb);
 
 	mrt = ip6mr_get_table(net, RT6_TABLE_DFLT);
-	if (mrt == NULL)
+	if (!mrt)
 		return -ENOENT;
 
 	read_lock(&mrt_lock);
@@ -2149,7 +2149,13 @@
 		}
 
 		dev = skb->dev;
-		if (dev == NULL || (vif = ip6mr_find_vif(mrt, dev)) < 0) {
+		if (!dev) {
+			read_unlock(&mrt_lock);
+			return -ENODEV;
+		}
+
+		vif = ip6mr_find_vif(mrt, dev);
+		if (vif < 0) {
 			read_unlock(&mrt_lock);
 			return -ENODEV;
 		}
@@ -2199,7 +2205,7 @@
 	struct rtmsg *rtm;
 
 	nlh = nlmsg_put(skb, pid, seq, RTM_NEWROUTE, sizeof(*rtm), NLM_F_MULTI);
-	if (nlh == NULL)
+	if (!nlh)
 		return -EMSGSIZE;
 
 	rtm = nlmsg_data(nlh);