net: skb->rtable accessor

Define skb_rtable(const struct sk_buff *skb) accessor to get rtable from skb

Delete skb->rtable field

Setting rtable is not allowed, just set dst instead as rtable is an alias.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

15 files changed, 57 insertions, 50 deletions

diff --git a/net/ipv4/arp.c b/net/ipv4/arp.c
index f11931c18381..816494f271a7 100644
--- a/net/ipv4/arp.c
+++ b/net/ipv4/arp.c
@@ -474,7 +474,7 @@ int arp_find(unsigned char *haddr, struct sk_buff *skb)
                 return 1;
         }
 
-        paddr = skb->rtable->rt_gateway;
+        paddr = skb_rtable(skb)->rt_gateway;
 
         if (arp_set_predefined(inet_addr_type(dev_net(dev), paddr), haddr, paddr, dev))
                 return 0;
@@ -817,7 +817,7 @@ static int arp_process(struct sk_buff *skb)
         if (arp->ar_op == htons(ARPOP_REQUEST) &&
             ip_route_input(skb, tip, sip, 0, dev) == 0) {
 
-                rt = skb->rtable;
+                rt = skb_rtable(skb);
                 addr_type = rt->rt_type;
 
                 if (addr_type == RTN_LOCAL) {
diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c
index 3f50807237e0..94f75efae938 100644
--- a/net/ipv4/icmp.c
+++ b/net/ipv4/icmp.c
@@ -356,7 +356,7 @@ static void icmp_push_reply(struct icmp_bxm *icmp_param,
 static void icmp_reply(struct icmp_bxm *icmp_param, struct sk_buff *skb)
 {
         struct ipcm_cookie ipc;
-        struct rtable *rt = skb->rtable;
+        struct rtable *rt = skb_rtable(skb);
         struct net *net = dev_net(rt->u.dst.dev);
         struct sock *sk;
         struct inet_sock *inet;
@@ -416,7 +416,7 @@ void icmp_send(struct sk_buff *skb_in, int type, int code, __be32 info)
         struct iphdr *iph;
         int room;
         struct icmp_bxm icmp_param;
-        struct rtable *rt = skb_in->rtable;
+        struct rtable *rt = skb_rtable(skb_in);
         struct ipcm_cookie ipc;
         __be32 saddr;
         u8  tos;
@@ -596,7 +596,7 @@ void icmp_send(struct sk_buff *skb_in, int type, int code, __be32 info)
                                              RT_TOS(tos), rt2->u.dst.dev);
 
                         dst_release(&rt2->u.dst);
-                        rt2 = skb_in->rtable;
+                        rt2 = skb_rtable(skb_in);
                         skb_in->dst = odst;
                 }
 
@@ -926,7 +926,7 @@ static void icmp_address(struct sk_buff *skb)
 
 static void icmp_address_reply(struct sk_buff *skb)
 {
-        struct rtable *rt = skb->rtable;
+        struct rtable *rt = skb_rtable(skb);
         struct net_device *dev = skb->dev;
         struct in_device *in_dev;
         struct in_ifaddr *ifa;
@@ -970,7 +970,7 @@ static void icmp_discard(struct sk_buff *skb)
 int icmp_rcv(struct sk_buff *skb)
 {
         struct icmphdr *icmph;
-        struct rtable *rt = skb->rtable;
+        struct rtable *rt = skb_rtable(skb);
         struct net *net = dev_net(rt->u.dst.dev);
 
         if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) {
diff --git a/net/ipv4/igmp.c b/net/ipv4/igmp.c
index e6058a503796..afabd2758b67 100644
--- a/net/ipv4/igmp.c
+++ b/net/ipv4/igmp.c
@@ -948,7 +948,7 @@ int igmp_rcv(struct sk_buff *skb)
         case IGMPV2_HOST_MEMBERSHIP_REPORT:
         case IGMPV3_HOST_MEMBERSHIP_REPORT:
                 /* Is it our report looped back? */
-                if (skb->rtable->fl.iif == 0)
+                if (skb_rtable(skb)->fl.iif == 0)
                         break;
                 /* don't rely on MC router hearing unicast reports */
                 if (skb->pkt_type == PACKET_MULTICAST ||
diff --git a/net/ipv4/ip_forward.c b/net/ipv4/ip_forward.c
index df3fe50bbf0d..0761cd9bbd10 100644
--- a/net/ipv4/ip_forward.c
+++ b/net/ipv4/ip_forward.c
@@ -81,7 +81,7 @@ int ip_forward(struct sk_buff *skb)
         if (!xfrm4_route_forward(skb))
                 goto drop;
 
-        rt = skb->rtable;
+        rt = skb_rtable(skb);
 
         if (opt->is_strictroute && rt->rt_dst != rt->rt_gateway)
                 goto sr_failed;
diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
index 77436e2732eb..85ddad45a918 100644
--- a/net/ipv4/ip_gre.c
+++ b/net/ipv4/ip_gre.c
@@ -602,7 +602,7 @@ static int ipgre_rcv(struct sk_buff *skb)
 #ifdef CONFIG_NET_IPGRE_BROADCAST
                 if (ipv4_is_multicast(iph->daddr)) {
                         /* Looped back packet, drop it! */
-                        if (skb->rtable->fl.iif == 0)
+                        if (skb_rtable(skb)->fl.iif == 0)
                                 goto drop;
                         stats->multicast++;
                         skb->pkt_type = PACKET_BROADCAST;
@@ -704,7 +704,7 @@ static int ipgre_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
                 }
 
                 if (skb->protocol == htons(ETH_P_IP)) {
-                        rt = skb->rtable;
+                        rt = skb_rtable(skb);
                         if ((dst = rt->rt_gateway) == 0)
                                 goto tx_error_icmp;
                 }
diff --git a/net/ipv4/ip_input.c b/net/ipv4/ip_input.c
index 40f6206b2aa9..cea784b0aa47 100644
--- a/net/ipv4/ip_input.c
+++ b/net/ipv4/ip_input.c
@@ -357,7 +357,7 @@ static int ip_rcv_finish(struct sk_buff *skb)
         if (iph->ihl > 5 && ip_rcv_options(skb))
                 goto drop;
 
-        rt = skb->rtable;
+        rt = skb_rtable(skb);
         if (rt->rt_type == RTN_MULTICAST) {
                 IP_UPD_PO_STATS_BH(dev_net(rt->u.dst.dev), IPSTATS_MIB_INMCAST,
                                 skb->len);
diff --git a/net/ipv4/ip_options.c b/net/ipv4/ip_options.c
index 2c88da6e7862..7e1074ffdbd1 100644
--- a/net/ipv4/ip_options.c
+++ b/net/ipv4/ip_options.c
@@ -102,7 +102,7 @@ int ip_options_echo(struct ip_options * dopt, struct sk_buff * skb)
         sptr = skb_network_header(skb);
         dptr = dopt->__data;
 
-        daddr = skb->rtable->rt_spec_dst;
+        daddr = skb_rtable(skb)->rt_spec_dst;
 
         if (sopt->rr) {
                 optlen  = sptr[sopt->rr+1];
@@ -257,7 +257,7 @@ int ip_options_compile(struct net *net,
         struct rtable *rt = NULL;
 
         if (skb != NULL) {
-                rt = skb->rtable;
+                rt = skb_rtable(skb);
                 optptr = (unsigned char *)&(ip_hdr(skb)[1]);
         } else
                 optptr = opt->__data;
@@ -550,7 +550,7 @@ void ip_forward_options(struct sk_buff *skb)
 {
         struct   ip_options * opt       = &(IPCB(skb)->opt);
         unsigned char * optptr;
-        struct rtable *rt = skb->rtable;
+        struct rtable *rt = skb_rtable(skb);
         unsigned char *raw = skb_network_header(skb);
 
         if (opt->rr_needaddr) {
@@ -598,7 +598,7 @@ int ip_options_rcv_srr(struct sk_buff *skb)
         __be32 nexthop;
         struct iphdr *iph = ip_hdr(skb);
         unsigned char *optptr = skb_network_header(skb) + opt->srr;
-        struct rtable *rt = skb->rtable;
+        struct rtable *rt = skb_rtable(skb);
         struct rtable *rt2;
         int err;
 
@@ -623,13 +623,13 @@ int ip_options_rcv_srr(struct sk_buff *skb)
                 }
                 memcpy(&nexthop, &optptr[srrptr-1], 4);
 
-                rt = skb->rtable;
-                skb->rtable = NULL;
+                rt = skb_rtable(skb);
+                skb->dst = NULL;
                 err = ip_route_input(skb, nexthop, iph->saddr, iph->tos, skb->dev);
-                rt2 = skb->rtable;
+                rt2 = skb_rtable(skb);
                 if (err || (rt2->rt_type != RTN_UNICAST && rt2->rt_type != RTN_LOCAL)) {
                         ip_rt_put(rt2);
-                        skb->rtable = rt;
+                        skb->dst = &rt->u.dst;
                         return -EINVAL;
                 }
                 ip_rt_put(rt);
diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index ea19c37ccc0c..8d845ebfccaa 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -140,7 +140,7 @@ int ip_build_and_send_pkt(struct sk_buff *skb, struct sock *sk,
                           __be32 saddr, __be32 daddr, struct ip_options *opt)
 {
         struct inet_sock *inet = inet_sk(sk);
-        struct rtable *rt = skb->rtable;
+        struct rtable *rt = skb_rtable(skb);
         struct iphdr *iph;
 
         /* Build the IP header. */
@@ -238,7 +238,7 @@ static int ip_finish_output(struct sk_buff *skb)
 int ip_mc_output(struct sk_buff *skb)
 {
         struct sock *sk = skb->sk;
-        struct rtable *rt = skb->rtable;
+        struct rtable *rt = skb_rtable(skb);
         struct net_device *dev = rt->u.dst.dev;
 
         /*
@@ -319,7 +319,7 @@ int ip_queue_xmit(struct sk_buff *skb, int ipfragok)
         /* Skip all of this if the packet is already routed,
          * f.e. by something like SCTP.
          */
-        rt = skb->rtable;
+        rt = skb_rtable(skb);
         if (rt != NULL)
                 goto packet_routed;
 
@@ -440,7 +440,7 @@ int ip_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *))
         unsigned int mtu, hlen, left, len, ll_rs, pad;
         int offset;
         __be16 not_last_frag;
-        struct rtable *rt = skb->rtable;
+        struct rtable *rt = skb_rtable(skb);
         int err = 0;
 
         dev = rt->u.dst.dev;
@@ -1362,7 +1362,7 @@ void ip_send_reply(struct sock *sk, struct sk_buff *skb, struct ip_reply_arg *ar
         } replyopts;
         struct ipcm_cookie ipc;
         __be32 daddr;
-        struct rtable *rt = skb->rtable;
+        struct rtable *rt = skb_rtable(skb);
 
         if (ip_options_echo(&replyopts.opt, skb))
                 return;
diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
index cb49936856e0..fc7993e9061f 100644
--- a/net/ipv4/ip_sockglue.c
+++ b/net/ipv4/ip_sockglue.c
@@ -57,7 +57,7 @@
 static void ip_cmsg_recv_pktinfo(struct msghdr *msg, struct sk_buff *skb)
 {
         struct in_pktinfo info;
-        struct rtable *rt = skb->rtable;
+        struct rtable *rt = skb_rtable(skb);
 
         info.ipi_addr.s_addr = ip_hdr(skb)->daddr;
         if (rt) {
diff --git a/net/ipv4/ipip.c b/net/ipv4/ipip.c
index bb2f1b17fbf1..0c6e7bf18a43 100644
--- a/net/ipv4/ipip.c
+++ b/net/ipv4/ipip.c
@@ -416,7 +416,7 @@ static int ipip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
 
         if (!dst) {
                 /* NBMA tunnel */
-                if ((rt = skb->rtable) == NULL) {
+                if ((rt = skb_rtable(skb)) == NULL) {
                         stats->tx_fifo_errors++;
                         goto tx_error;
                 }
diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c
index 13e9dd3012b3..69dd058283eb 100644
--- a/net/ipv4/ipmr.c
+++ b/net/ipv4/ipmr.c
@@ -1354,7 +1354,7 @@ static int ip_mr_forward(struct sk_buff *skb, struct mfc_cache *cache, int local
         if (net->ipv4.vif_table[vif].dev != skb->dev) {
                 int true_vifi;
 
-                if (skb->rtable->fl.iif == 0) {
+                if (skb_rtable(skb)->fl.iif == 0) {
                         /* It is our own packet, looped back.
                            Very complicated situation...
 
@@ -1430,7 +1430,7 @@ int ip_mr_input(struct sk_buff *skb)
 {
         struct mfc_cache *cache;
         struct net *net = dev_net(skb->dev);
-        int local = skb->rtable->rt_flags&RTCF_LOCAL;
+        int local = skb_rtable(skb)->rt_flags & RTCF_LOCAL;
 
         /* Packet is looped back after forward, it should not be
            forwarded second time, but still can be delivered locally.
@@ -1646,7 +1646,7 @@ int ipmr_get_route(struct net *net,
 {
         int err;
         struct mfc_cache *cache;
-        struct rtable *rt = skb->rtable;
+        struct rtable *rt = skb_rtable(skb);
 
         read_lock(&mrt_lock);
         cache = ipmr_cache_find(net, rt->rt_src, rt->rt_dst);
diff --git a/net/ipv4/netfilter/ipt_MASQUERADE.c b/net/ipv4/netfilter/ipt_MASQUERADE.c
index f389f60cb105..c0992c75bdac 100644
--- a/net/ipv4/netfilter/ipt_MASQUERADE.c
+++ b/net/ipv4/netfilter/ipt_MASQUERADE.c
@@ -72,7 +72,7 @@ masquerade_tg(struct sk_buff *skb, const struct xt_target_param *par)
                 return NF_ACCEPT;
 
         mr = par->targinfo;
-        rt = skb->rtable;
+        rt = skb_rtable(skb);
         newsrc = inet_select_addr(par->out, rt->rt_gateway, RT_SCOPE_UNIVERSE);
         if (!newsrc) {
                 printk("MASQUERADE: %s ate my IP address\n", par->out->name);
diff --git a/net/ipv4/netfilter/nf_nat_helper.c b/net/ipv4/netfilter/nf_nat_helper.c
index cf7a42bf9820..155c008626c8 100644
--- a/net/ipv4/netfilter/nf_nat_helper.c
+++ b/net/ipv4/netfilter/nf_nat_helper.c
@@ -140,7 +140,7 @@ nf_nat_mangle_tcp_packet(struct sk_buff *skb,
                          const char *rep_buffer,
                          unsigned int rep_len)
 {
-        struct rtable *rt = skb->rtable;
+        struct rtable *rt = skb_rtable(skb);
         struct iphdr *iph;
         struct tcphdr *tcph;
         int oldlen, datalen;
@@ -218,7 +218,7 @@ nf_nat_mangle_udp_packet(struct sk_buff *skb,
                          const char *rep_buffer,
                          unsigned int rep_len)
 {
-        struct rtable *rt = skb->rtable;
+        struct rtable *rt = skb_rtable(skb);
         struct iphdr *iph;
         struct udphdr *udph;
         int datalen, oldlen;
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 28205e5bfa9b..f20060ac2f09 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -1064,7 +1064,8 @@ work_done:
 out:    return 0;
 }
 
-static int rt_intern_hash(unsigned hash, struct rtable *rt, struct rtable **rp)
+static int rt_intern_hash(unsigned hash, struct rtable *rt,
+                          struct rtable **rp, struct sk_buff *skb)
 {
         struct rtable   *rth, **rthp;
         unsigned long   now;
@@ -1114,7 +1115,10 @@ restart:
                         spin_unlock_bh(rt_hash_lock_addr(hash));
 
                         rt_drop(rt);
-                        *rp = rth;
+                        if (rp)
+                                *rp = rth;
+                        else
+                                skb->dst = &rth->u.dst;
                         return 0;
                 }
 
@@ -1210,7 +1214,10 @@ restart:
         rcu_assign_pointer(rt_hash_table[hash].chain, rt);
 
         spin_unlock_bh(rt_hash_lock_addr(hash));
-        *rp = rt;
+        if (rp)
+                *rp = rt;
+        else
+                skb->dst = &rt->u.dst;
         return 0;
 }
 
@@ -1407,7 +1414,7 @@ void ip_rt_redirect(__be32 old_gw, __be32 daddr, __be32 new_gw,
                                                         &netevent);
 
                                 rt_del(hash, rth);
-                                if (!rt_intern_hash(hash, rt, &rt))
+                                if (!rt_intern_hash(hash, rt, &rt, NULL))
                                         ip_rt_put(rt);
                                 goto do_next;
                         }
@@ -1473,7 +1480,7 @@ static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst)
 
 void ip_rt_send_redirect(struct sk_buff *skb)
 {
-        struct rtable *rt = skb->rtable;
+        struct rtable *rt = skb_rtable(skb);
         struct in_device *in_dev = in_dev_get(rt->u.dst.dev);
 
         if (!in_dev)
@@ -1521,7 +1528,7 @@ out:
 
 static int ip_error(struct sk_buff *skb)
 {
-        struct rtable *rt = skb->rtable;
+        struct rtable *rt = skb_rtable(skb);
         unsigned long now;
         int code;
 
@@ -1698,7 +1705,7 @@ static void ipv4_link_failure(struct sk_buff *skb)
 
         icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0);
 
-        rt = skb->rtable;
+        rt = skb_rtable(skb);
         if (rt)
                 dst_set_expires(&rt->u.dst, 0);
 }
@@ -1858,7 +1865,7 @@ static int ip_route_input_mc(struct sk_buff *skb, __be32 daddr, __be32 saddr,
 
         in_dev_put(in_dev);
         hash = rt_hash(daddr, saddr, dev->ifindex, rt_genid(dev_net(dev)));
-        return rt_intern_hash(hash, rth, &skb->rtable);
+        return rt_intern_hash(hash, rth, NULL, skb);
 
 e_nobufs:
         in_dev_put(in_dev);
@@ -2019,7 +2026,7 @@ static int ip_mkroute_input(struct sk_buff *skb,
         /* put it into the cache */
         hash = rt_hash(daddr, saddr, fl->iif,
                        rt_genid(dev_net(rth->u.dst.dev)));
-        return rt_intern_hash(hash, rth, &skb->rtable);
+        return rt_intern_hash(hash, rth, NULL, skb);
 }
 
 /*
@@ -2175,7 +2182,7 @@ local_input:
         }
         rth->rt_type    = res.type;
         hash = rt_hash(daddr, saddr, fl.iif, rt_genid(net));
-        err = rt_intern_hash(hash, rth, &skb->rtable);
+        err = rt_intern_hash(hash, rth, NULL, skb);
         goto done;
 
 no_route:
@@ -2244,7 +2251,7 @@ int ip_route_input(struct sk_buff *skb, __be32 daddr, __be32 saddr,
                         dst_use(&rth->u.dst, jiffies);
                         RT_CACHE_STAT_INC(in_hit);
                         rcu_read_unlock();
-                        skb->rtable = rth;
+                        skb->dst = &rth->u.dst;
                         return 0;
                 }
                 RT_CACHE_STAT_INC(in_hlist_search);
@@ -2420,7 +2427,7 @@ static int ip_mkroute_output(struct rtable **rp,
         if (err == 0) {
                 hash = rt_hash(oldflp->fl4_dst, oldflp->fl4_src, oldflp->oif,
                                rt_genid(dev_net(dev_out)));
-                err = rt_intern_hash(hash, rth, rp);
+                err = rt_intern_hash(hash, rth, rp, NULL);
         }
 
         return err;
@@ -2763,7 +2770,7 @@ static int rt_fill_info(struct net *net,
                         struct sk_buff *skb, u32 pid, u32 seq, int event,
                         int nowait, unsigned int flags)
 {
-        struct rtable *rt = skb->rtable;
+        struct rtable *rt = skb_rtable(skb);
         struct rtmsg *r;
         struct nlmsghdr *nlh;
         long expires;
@@ -2907,7 +2914,7 @@ static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh, void
                 err = ip_route_input(skb, dst, src, rtm->rtm_tos, dev);
                 local_bh_enable();
 
-                rt = skb->rtable;
+                rt = skb_rtable(skb);
                 if (err == 0 && rt->u.dst.error)
                         err = -rt->u.dst.error;
         } else {
@@ -2927,7 +2934,7 @@ static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh, void
         if (err)
                 goto errout_free;
 
-        skb->rtable = rt;
+        skb->dst = &rt->u.dst;
         if (rtm->rtm_flags & RTM_F_NOTIFY)
                 rt->rt_flags |= RTCF_NOTIFY;
 
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index fc79e3416288..319c88526449 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -546,7 +546,7 @@ static void tcp_v4_send_reset(struct sock *sk, struct sk_buff *skb)
         if (th->rst)
                 return;
 
-        if (skb->rtable->rt_type != RTN_LOCAL)
+        if (skb_rtable(skb)->rt_type != RTN_LOCAL)
                 return;
 
         /* Swap the send and the receive. */
@@ -1185,7 +1185,7 @@ int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
 #endif
 
         /* Never answer to SYNs send to broadcast or multicast */
-        if (skb->rtable->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST))
+        if (skb_rtable(skb)->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST))
                 goto drop;
 
         /* TW buckets are converted to open requests without