ipv4: Use caller's on-stack flowi as-is in output route lookups.

Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/route.h b/include/net/route.h
index fdbdb9271d7fb322a2942f9ad17d2695fdda61c3..81b6cf27654999b9ec267416b034770c56058daa 100644 (file)
--- a/include/net/route.h
+++ b/include/net/route.h
@@ -115,7 +115,7 @@ extern void         ip_rt_redirect(__be32 old_gw, __be32 dst, __be32 new_gw,
                                       __be32 src, struct net_device *dev);
 extern void            rt_cache_flush(struct net *net, int how);
 extern void            rt_cache_flush_batch(struct net *net);
-extern struct rtable *__ip_route_output_key(struct net *, const struct flowi4 *flp);
+extern struct rtable *__ip_route_output_key(struct net *, struct flowi4 *flp);
 extern struct rtable *ip_route_output_flow(struct net *, struct flowi4 *flp,
                                           struct sock *sk);
 extern struct dst_entry *ipv4_blackhole_route(struct net *net, struct dst_entry *dst_orig);

diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index fb9211adf079592b8370930566452a79a64abac9..93f71be1d5d1ec33c21bfc7018477ee16068d264 100644 (file)
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -1767,7 +1767,7 @@ static unsigned int ipv4_default_mtu(const struct dst_entry *dst)
        return mtu;
 }
 
-static void rt_init_metrics(struct rtable *rt, const struct flowi4 *oldflp4,
+static void rt_init_metrics(struct rtable *rt, const struct flowi4 *fl4,
                            struct fib_info *fi)
 {
        struct inet_peer *peer;
@@ -1776,7 +1776,7 @@ static void rt_init_metrics(struct rtable *rt, const struct flowi4 *oldflp4,
        /* If a peer entry exists for this destination, we must hook
         * it up in order to get at cached metrics.
         */
-       if (oldflp4 && (oldflp4->flowi4_flags & FLOWI_FLAG_PRECOW_METRICS))
+       if (fl4 && (fl4->flowi4_flags & FLOWI_FLAG_PRECOW_METRICS))
                create = 1;
 
        rt->peer = peer = inet_getpeer_v4(rt->rt_dst, create);
@@ -1803,7 +1803,7 @@ static void rt_init_metrics(struct rtable *rt, const struct flowi4 *oldflp4,
        }
 }
 
-static void rt_set_nexthop(struct rtable *rt, const struct flowi4 *oldflp4,
+static void rt_set_nexthop(struct rtable *rt, const struct flowi4 *fl4,
                           const struct fib_result *res,
                           struct fib_info *fi, u16 type, u32 itag)
 {
@@ -1813,7 +1813,7 @@ static void rt_set_nexthop(struct rtable *rt, const struct flowi4 *oldflp4,
                if (FIB_RES_GW(*res) &&
                    FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK)
                        rt->rt_gateway = FIB_RES_GW(*res);
-               rt_init_metrics(rt, oldflp4, fi);
+               rt_init_metrics(rt, fl4, fi);
 #ifdef CONFIG_IP_ROUTE_CLASSID
                dst->tclassid = FIB_RES_NH(*res).nh_tclassid;
 #endif
@@ -2354,12 +2354,12 @@ EXPORT_SYMBOL(ip_route_input_common);
 /* called with rcu_read_lock() */
 static struct rtable *__mkroute_output(const struct fib_result *res,
                                       const struct flowi4 *fl4,
-                                      const struct flowi4 *oldflp4,
-                                      struct net_device *dev_out,
+                                      __be32 orig_daddr, __be32 orig_saddr,
+                                      int orig_oif, struct net_device *dev_out,
                                       unsigned int flags)
 {
        struct fib_info *fi = res->fi;
-       u32 tos = RT_FL_TOS(oldflp4);
+       u32 tos = RT_FL_TOS(fl4);
        struct in_device *in_dev;
        u16 type = res->type;
        struct rtable *rth;
@@ -2386,8 +2386,8 @@ static struct rtable *__mkroute_output(const struct fib_result *res,
                fi = NULL;
        } else if (type == RTN_MULTICAST) {
                flags |= RTCF_MULTICAST | RTCF_LOCAL;
-               if (!ip_check_mc_rcu(in_dev, oldflp4->daddr, oldflp4->saddr,
-                                    oldflp4->flowi4_proto))
+               if (!ip_check_mc_rcu(in_dev, fl4->daddr, fl4->saddr,
+                                    fl4->flowi4_proto))
                        flags &= ~RTCF_LOCAL;
                /* If multicast route do not exist use
                 * default one, but do not gateway in this case.
@@ -2405,8 +2405,8 @@ static struct rtable *__mkroute_output(const struct fib_result *res,
 
        rth->dst.output = ip_output;
 
-       rth->rt_key_dst = oldflp4->daddr;
-       rth->rt_key_src = oldflp4->saddr;
+       rth->rt_key_dst = orig_daddr;
+       rth->rt_key_src = orig_saddr;
        rth->rt_genid = rt_genid(dev_net(dev_out));
        rth->rt_flags   = flags;
        rth->rt_type    = type;
@@ -2414,9 +2414,9 @@ static struct rtable *__mkroute_output(const struct fib_result *res,
        rth->rt_dst     = fl4->daddr;
        rth->rt_src     = fl4->saddr;
        rth->rt_route_iif = 0;
-       rth->rt_iif     = oldflp4->flowi4_oif ? : dev_out->ifindex;
-       rth->rt_oif     = oldflp4->flowi4_oif;
-       rth->rt_mark    = oldflp4->flowi4_mark;
+       rth->rt_iif     = orig_oif ? : dev_out->ifindex;
+       rth->rt_oif     = orig_oif;
+       rth->rt_mark    = fl4->flowi4_mark;
        rth->rt_gateway = fl4->daddr;
        rth->rt_spec_dst= fl4->saddr;
        rth->rt_peer_genid = 0;
@@ -2439,7 +2439,7 @@ static struct rtable *__mkroute_output(const struct fib_result *res,
 #ifdef CONFIG_IP_MROUTE
                if (type == RTN_MULTICAST) {
                        if (IN_DEV_MFORWARD(in_dev) &&
-                           !ipv4_is_local_multicast(oldflp4->daddr)) {
+                           !ipv4_is_local_multicast(fl4->daddr)) {
                                rth->dst.input = ip_mr_input;
                                rth->dst.output = ip_mc_output;
                        }
@@ -2447,7 +2447,7 @@ static struct rtable *__mkroute_output(const struct fib_result *res,
 #endif
        }
 
-       rt_set_nexthop(rth, oldflp4, res, fi, type, 0);
+       rt_set_nexthop(rth, fl4, res, fi, type, 0);
 
        return rth;
 }
@@ -2457,36 +2457,37 @@ static struct rtable *__mkroute_output(const struct fib_result *res,
  * called with rcu_read_lock();
  */
 
-static struct rtable *ip_route_output_slow(struct net *net,
-                                          const struct flowi4 *oldflp4)
+static struct rtable *ip_route_output_slow(struct net *net, struct flowi4 *fl4)
 {
-       u32 tos = RT_FL_TOS(oldflp4);
-       struct flowi4 fl4;
-       struct fib_result res;
-       unsigned int flags = 0;
        struct net_device *dev_out = NULL;
+       u32 tos = RT_FL_TOS(fl4);
+       unsigned int flags = 0;
+       struct fib_result res;
        struct rtable *rth;
+       __be32 orig_daddr;
+       __be32 orig_saddr;
+       int orig_oif;
 
        res.fi          = NULL;
 #ifdef CONFIG_IP_MULTIPLE_TABLES
        res.r           = NULL;
 #endif
 
-       fl4.flowi4_oif = oldflp4->flowi4_oif;
-       fl4.flowi4_iif = net->loopback_dev->ifindex;
-       fl4.flowi4_mark = oldflp4->flowi4_mark;
-       fl4.daddr = oldflp4->daddr;
-       fl4.saddr = oldflp4->saddr;
-       fl4.flowi4_tos = tos & IPTOS_RT_MASK;
-       fl4.flowi4_scope = ((tos & RTO_ONLINK) ?
-                       RT_SCOPE_LINK : RT_SCOPE_UNIVERSE);
+       orig_daddr = fl4->daddr;
+       orig_saddr = fl4->saddr;
+       orig_oif = fl4->flowi4_oif;
+
+       fl4->flowi4_iif = net->loopback_dev->ifindex;
+       fl4->flowi4_tos = tos & IPTOS_RT_MASK;
+       fl4->flowi4_scope = ((tos & RTO_ONLINK) ?
+                        RT_SCOPE_LINK : RT_SCOPE_UNIVERSE);
 
        rcu_read_lock();
-       if (oldflp4->saddr) {
+       if (fl4->saddr) {
                rth = ERR_PTR(-EINVAL);
-               if (ipv4_is_multicast(oldflp4->saddr) ||
-                   ipv4_is_lbcast(oldflp4->saddr) ||
-                   ipv4_is_zeronet(oldflp4->saddr))
+               if (ipv4_is_multicast(fl4->saddr) ||
+                   ipv4_is_lbcast(fl4->saddr) ||
+                   ipv4_is_zeronet(fl4->saddr))
                        goto out;
 
                /* I removed check for oif == dev_out->oif here.
@@ -2497,11 +2498,11 @@ static struct rtable *ip_route_output_slow(struct net *net,
                      of another iface. --ANK
                 */
 
-               if (oldflp4->flowi4_oif == 0 &&
-                   (ipv4_is_multicast(oldflp4->daddr) ||
-                    ipv4_is_lbcast(oldflp4->daddr))) {
+               if (fl4->flowi4_oif == 0 &&
+                   (ipv4_is_multicast(fl4->daddr) ||
+                    ipv4_is_lbcast(fl4->daddr))) {
                        /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */
-                       dev_out = __ip_dev_find(net, oldflp4->saddr, false);
+                       dev_out = __ip_dev_find(net, fl4->saddr, false);
                        if (dev_out == NULL)
                                goto out;
 
@@ -2520,20 +2521,20 @@ static struct rtable *ip_route_output_slow(struct net *net,
                           Luckily, this hack is good workaround.
                         */
 
-                       fl4.flowi4_oif = dev_out->ifindex;
+                       fl4->flowi4_oif = dev_out->ifindex;
                        goto make_route;
                }
 
-               if (!(oldflp4->flowi4_flags & FLOWI_FLAG_ANYSRC)) {
+               if (!(fl4->flowi4_flags & FLOWI_FLAG_ANYSRC)) {
                        /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */
-                       if (!__ip_dev_find(net, oldflp4->saddr, false))
+                       if (!__ip_dev_find(net, fl4->saddr, false))
                                goto out;
                }
        }
 
 
-       if (oldflp4->flowi4_oif) {
-               dev_out = dev_get_by_index_rcu(net, oldflp4->flowi4_oif);
+       if (fl4->flowi4_oif) {
+               dev_out = dev_get_by_index_rcu(net, fl4->flowi4_oif);
                rth = ERR_PTR(-ENODEV);
                if (dev_out == NULL)
                        goto out;
@@ -2543,37 +2544,37 @@ static struct rtable *ip_route_output_slow(struct net *net,
                        rth = ERR_PTR(-ENETUNREACH);
                        goto out;
                }
-               if (ipv4_is_local_multicast(oldflp4->daddr) ||
-                   ipv4_is_lbcast(oldflp4->daddr)) {
-                       if (!fl4.saddr)
-                               fl4.saddr = inet_select_addr(dev_out, 0,
-                                                            RT_SCOPE_LINK);
+               if (ipv4_is_local_multicast(fl4->daddr) ||
+                   ipv4_is_lbcast(fl4->daddr)) {
+                       if (!fl4->saddr)
+                               fl4->saddr = inet_select_addr(dev_out, 0,
+                                                             RT_SCOPE_LINK);
                        goto make_route;
                }
-               if (!fl4.saddr) {
-                       if (ipv4_is_multicast(oldflp4->daddr))
-                               fl4.saddr = inet_select_addr(dev_out, 0,
-                                                            fl4.flowi4_scope);
-                       else if (!oldflp4->daddr)
-                               fl4.saddr = inet_select_addr(dev_out, 0,
-                                                            RT_SCOPE_HOST);
+               if (fl4->saddr) {
+                       if (ipv4_is_multicast(fl4->daddr))
+                               fl4->saddr = inet_select_addr(dev_out, 0,
+                                                             fl4->flowi4_scope);
+                       else if (!fl4->daddr)
+                               fl4->saddr = inet_select_addr(dev_out, 0,
+                                                             RT_SCOPE_HOST);
                }
        }
 
-       if (!fl4.daddr) {
-               fl4.daddr = fl4.saddr;
-               if (!fl4.daddr)
-                       fl4.daddr = fl4.saddr = htonl(INADDR_LOOPBACK);
+       if (!fl4->daddr) {
+               fl4->daddr = fl4->saddr;
+               if (!fl4->daddr)
+                       fl4->daddr = fl4->saddr = htonl(INADDR_LOOPBACK);
                dev_out = net->loopback_dev;
-               fl4.flowi4_oif = net->loopback_dev->ifindex;
+               fl4->flowi4_oif = net->loopback_dev->ifindex;
                res.type = RTN_LOCAL;
                flags |= RTCF_LOCAL;
                goto make_route;
        }
 
-       if (fib_lookup(net, &fl4, &res)) {
+       if (fib_lookup(net, fl4, &res)) {
                res.fi = NULL;
-               if (oldflp4->flowi4_oif) {
+               if (fl4->flowi4_oif) {
                        /* Apparently, routing tables are wrong. Assume,
                           that the destination is on link.
 
@@ -2592,9 +2593,9 @@ static struct rtable *ip_route_output_slow(struct net *net,
                           likely IPv6, but we do not.
                         */
 
-                       if (fl4.saddr == 0)
-                               fl4.saddr = inet_select_addr(dev_out, 0,
-                                                            RT_SCOPE_LINK);
+                       if (fl4->saddr == 0)
+                               fl4->saddr = inet_select_addr(dev_out, 0,
+                                                             RT_SCOPE_LINK);
                        res.type = RTN_UNICAST;
                        goto make_route;
                }
@@ -2603,44 +2604,45 @@ static struct rtable *ip_route_output_slow(struct net *net,
        }
 
        if (res.type == RTN_LOCAL) {
-               if (!fl4.saddr) {
+               if (!fl4->saddr) {
                        if (res.fi->fib_prefsrc)
-                               fl4.saddr = res.fi->fib_prefsrc;
+                               fl4->saddr = res.fi->fib_prefsrc;
                        else
-                               fl4.saddr = fl4.daddr;
+                               fl4->saddr = fl4->daddr;
                }
                dev_out = net->loopback_dev;
-               fl4.flowi4_oif = dev_out->ifindex;
+               fl4->flowi4_oif = dev_out->ifindex;
                res.fi = NULL;
                flags |= RTCF_LOCAL;
                goto make_route;
        }
 
 #ifdef CONFIG_IP_ROUTE_MULTIPATH
-       if (res.fi->fib_nhs > 1 && fl4.flowi4_oif == 0)
+       if (res.fi->fib_nhs > 1 && fl4->flowi4_oif == 0)
                fib_select_multipath(&res);
        else
 #endif
        if (!res.prefixlen &&
            res.table->tb_num_default > 1 &&
-           res.type == RTN_UNICAST && !fl4.flowi4_oif)
+           res.type == RTN_UNICAST && !fl4->flowi4_oif)
                fib_select_default(&res);
 
-       if (!fl4.saddr)
-               fl4.saddr = FIB_RES_PREFSRC(net, res);
+       if (!fl4->saddr)
+               fl4->saddr = FIB_RES_PREFSRC(net, res);
 
        dev_out = FIB_RES_DEV(res);
-       fl4.flowi4_oif = dev_out->ifindex;
+       fl4->flowi4_oif = dev_out->ifindex;
 
 
 make_route:
-       rth = __mkroute_output(&res, &fl4, oldflp4, dev_out, flags);
+       rth = __mkroute_output(&res, fl4, orig_daddr, orig_saddr, orig_oif,
+                              dev_out, flags);
        if (!IS_ERR(rth)) {
                unsigned int hash;
 
-               hash = rt_hash(oldflp4->daddr, oldflp4->saddr, oldflp4->flowi4_oif,
+               hash = rt_hash(orig_daddr, orig_saddr, orig_oif,
                               rt_genid(dev_net(dev_out)));
-               rth = rt_intern_hash(hash, rth, NULL, oldflp4->flowi4_oif);
+               rth = rt_intern_hash(hash, rth, NULL, orig_oif);
        }
 
 out:
@@ -2648,7 +2650,7 @@ out:
        return rth;
 }
 
-struct rtable *__ip_route_output_key(struct net *net, const struct flowi4 *flp4)
+struct rtable *__ip_route_output_key(struct net *net, struct flowi4 *flp4)
 {
        struct rtable *rth;
        unsigned int hash;