inet: Use fallthrough;

Convert the various uses of fallthrough comments to fallthrough;

Done via script
Link: https://lore.kernel.org/lkml/b56602fcf79f849e733e7b521bb0e17895d390fa.1582230379.git.joe@perches.com/

And by hand:

net/ipv6/ip6_fib.c has a fallthrough comment outside of an #ifdef block
that causes gcc to emit a warning if converted in-place.

So move the new fallthrough; inside the containing #ifdef/#endif too.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index cb493e1..c614249d 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -3299,7 +3299,7 @@ static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
 	switch (idev->cnf.addr_gen_mode) {
 	case IN6_ADDR_GEN_MODE_RANDOM:
 		ipv6_gen_mode_random_init(idev);
-		/* fallthrough */
+		fallthrough;
 	case IN6_ADDR_GEN_MODE_STABLE_PRIVACY:
 		if (!ipv6_generate_stable_address(&addr, 0, idev))
 			addrconf_add_linklocal(idev, &addr,
@@ -3517,9 +3517,7 @@ static int addrconf_notify(struct notifier_block *this, unsigned long event,
 			break;
 
 		run_pending = 1;
-
-		/* fall through */
-
+		fallthrough;
 	case NETDEV_UP:
 	case NETDEV_CHANGE:
 		if (dev->flags & IFF_SLAVE)
diff --git a/net/ipv6/ah6.c b/net/ipv6/ah6.c
index 871d6e5..45e2adc 100644
--- a/net/ipv6/ah6.c
+++ b/net/ipv6/ah6.c
@@ -259,7 +259,7 @@ static int ipv6_clear_mutable_options(struct ipv6hdr *iph, int len, int dir)
 		case NEXTHDR_DEST:
 			if (dir == XFRM_POLICY_OUT)
 				ipv6_rearrange_destopt(iph, exthdr.opth);
-			/* fall through */
+			fallthrough;
 		case NEXTHDR_HOP:
 			if (!zero_out_mutable_opts(exthdr.opth)) {
 				net_dbg_ratelimited("overrun %sopts\n",
diff --git a/net/ipv6/exthdrs.c b/net/ipv6/exthdrs.c
index ab5add0..bcb9f5e 100644
--- a/net/ipv6/exthdrs.c
+++ b/net/ipv6/exthdrs.c
@@ -97,7 +97,7 @@ static bool ip6_tlvopt_unknown(struct sk_buff *skb, int optoff,
 		 */
 		if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr))
 			break;
-		/* fall through */
+		fallthrough;
 	case 2: /* send ICMP PARM PROB regardless and drop packet */
 		icmpv6_param_prob(skb, ICMPV6_UNK_OPTION, optoff);
 		return false;
diff --git a/net/ipv6/icmp.c b/net/ipv6/icmp.c
index ef408a5..2688f3e8 100644
--- a/net/ipv6/icmp.c
+++ b/net/ipv6/icmp.c
@@ -898,7 +898,7 @@ static int icmpv6_rcv(struct sk_buff *skb)
 		hdr = icmp6_hdr(skb);
 
 		/* to notify */
-		/* fall through */
+		fallthrough;
 	case ICMPV6_DEST_UNREACH:
 	case ICMPV6_TIME_EXCEED:
 	case ICMPV6_PARAMPROB:
diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c
index 72abf89..46ed567 100644
--- a/net/ipv6/ip6_fib.c
+++ b/net/ipv6/ip6_fib.c
@@ -2068,8 +2068,8 @@ static int fib6_walk_continue(struct fib6_walker *w)
 				continue;
 			}
 			w->state = FWS_L;
+			fallthrough;
 #endif
-			/* fall through */
 		case FWS_L:
 			left = rcu_dereference_protected(fn->left, 1);
 			if (left) {
@@ -2078,7 +2078,7 @@ static int fib6_walk_continue(struct fib6_walker *w)
 				continue;
 			}
 			w->state = FWS_R;
-			/* fall through */
+			fallthrough;
 		case FWS_R:
 			right = rcu_dereference_protected(fn->right, 1);
 			if (right) {
@@ -2088,7 +2088,7 @@ static int fib6_walk_continue(struct fib6_walker *w)
 			}
 			w->state = FWS_C;
 			w->leaf = rcu_dereference_protected(fn->leaf, 1);
-			/* fall through */
+			fallthrough;
 		case FWS_C:
 			if (w->leaf && fn->fn_flags & RTN_RTINFO) {
 				int err;
@@ -2107,7 +2107,7 @@ static int fib6_walk_continue(struct fib6_walker *w)
 			}
 skip:
 			w->state = FWS_U;
-			/* fall through */
+			fallthrough;
 		case FWS_U:
 			if (fn == w->root)
 				return 0;
diff --git a/net/ipv6/ip6mr.c b/net/ipv6/ip6mr.c
index d648392..65a54d7 100644
--- a/net/ipv6/ip6mr.c
+++ b/net/ipv6/ip6mr.c
@@ -1691,7 +1691,7 @@ int ip6_mroute_setsockopt(struct sock *sk, int optname, char __user *optval, uns
 	case MRT6_ADD_MFC:
 	case MRT6_DEL_MFC:
 		parent = -1;
-		/* fall through */
+		fallthrough;
 	case MRT6_ADD_MFC_PROXY:
 	case MRT6_DEL_MFC_PROXY:
 		if (optlen < sizeof(mfc))
diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c
index 53caf59..4a3fecc 100644
--- a/net/ipv6/ndisc.c
+++ b/net/ipv6/ndisc.c
@@ -1782,7 +1782,7 @@ static int ndisc_netdev_event(struct notifier_block *this, unsigned long event,
 	case NETDEV_CHANGEADDR:
 		neigh_changeaddr(&nd_tbl, dev);
 		fib6_run_gc(0, net, false);
-		/* fallthrough */
+		fallthrough;
 	case NETDEV_UP:
 		idev = in6_dev_get(dev);
 		if (!idev)
diff --git a/net/ipv6/netfilter/nf_log_ipv6.c b/net/ipv6/netfilter/nf_log_ipv6.c
index 22b80db..da64550 100644
--- a/net/ipv6/netfilter/nf_log_ipv6.c
+++ b/net/ipv6/netfilter/nf_log_ipv6.c
@@ -248,7 +248,7 @@ static void dump_ipv6_packet(struct net *net, struct nf_log_buf *m,
 			/* Max length: 17 "POINTER=ffffffff " */
 			nf_log_buf_add(m, "POINTER=%08x ",
 				       ntohl(ic->icmp6_pointer));
-			/* Fall through */
+			fallthrough;
 		case ICMPV6_DEST_UNREACH:
 		case ICMPV6_PKT_TOOBIG:
 		case ICMPV6_TIME_EXCEED:
diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c
index dfe5e60..0028aa1 100644
--- a/net/ipv6/raw.c
+++ b/net/ipv6/raw.c
@@ -1076,7 +1076,7 @@ static int rawv6_setsockopt(struct sock *sk, int level, int optname,
 		if (optname == IPV6_CHECKSUM ||
 		    optname == IPV6_HDRINCL)
 			break;
-		/* fall through */
+		fallthrough;
 	default:
 		return ipv6_setsockopt(sk, level, optname, optval, optlen);
 	}
@@ -1099,7 +1099,7 @@ static int compat_rawv6_setsockopt(struct sock *sk, int level, int optname,
 		if (optname == IPV6_CHECKSUM ||
 		    optname == IPV6_HDRINCL)
 			break;
-		/* fall through */
+		fallthrough;
 	default:
 		return compat_ipv6_setsockopt(sk, level, optname,
 					      optval, optlen);
@@ -1161,7 +1161,7 @@ static int rawv6_getsockopt(struct sock *sk, int level, int optname,
 		if (optname == IPV6_CHECKSUM ||
 		    optname == IPV6_HDRINCL)
 			break;
-		/* fall through */
+		fallthrough;
 	default:
 		return ipv6_getsockopt(sk, level, optname, optval, optlen);
 	}
@@ -1184,7 +1184,7 @@ static int compat_rawv6_getsockopt(struct sock *sk, int level, int optname,
 		if (optname == IPV6_CHECKSUM ||
 		    optname == IPV6_HDRINCL)
 			break;
-		/* fall through */
+		fallthrough;
 	default:
 		return compat_ipv6_getsockopt(sk, level, optname,
 					      optval, optlen);
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 2931224..2430c2f 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -4370,7 +4370,7 @@ static int ip6_pkt_drop(struct sk_buff *skb, u8 code, int ipstats_mib_noroutes)
 			IP6_INC_STATS(net, idev, IPSTATS_MIB_INADDRERRORS);
 			break;
 		}
-		/* FALLTHROUGH */
+		fallthrough;
 	case IPSTATS_MIB_OUTNOROUTES:
 		IP6_INC_STATS(net, idev, ipstats_mib_noroutes);
 		break;
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index eaf09e6..413b342 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -1742,7 +1742,7 @@ INDIRECT_CALLABLE_SCOPE int tcp_v6_rcv(struct sk_buff *skb)
 		}
 	}
 		/* to ACK */
-		/* fall through */
+		fallthrough;
 	case TCP_TW_ACK:
 		tcp_v6_timewait_ack(sk, skb);
 		break;