ipv6: Fix inet6_csk_bind_conflict()
[safe/jmp/linux-2.6] / net / ipv4 / ip_fragment.c
index 8b448c4..75347ea 100644 (file)
@@ -5,10 +5,8 @@
  *
  *             The IP fragmentation functionality.
  *
- * Version:    $Id: ip_fragment.c,v 1.59 2002/01/12 07:54:56 davem Exp $
- *
  * Authors:    Fred N. van Kempen <waltje@uWalt.NL.Mugnet.ORG>
- *             Alan Cox <Alan.Cox@linux.org>
+ *             Alan Cox <alan@lxorguk.ukuu.org.uk>
  *
  * Fixes:
  *             Alan Cox        :       Split from ip.c , see ip_input.c for history.
@@ -34,6 +32,9 @@
 #include <linux/netdevice.h>
 #include <linux/jhash.h>
 #include <linux/random.h>
+#include <linux/slab.h>
+#include <net/route.h>
+#include <net/dst.h>
 #include <net/sock.h>
 #include <net/ip.h>
 #include <net/icmp.h>
@@ -58,7 +59,7 @@ struct ipfrag_skb_cb
        int                     offset;
 };
 
-#define FRAG_CB(skb)   ((struct ipfrag_skb_cb*)((skb)->cb))
+#define FRAG_CB(skb)   ((struct ipfrag_skb_cb *)((skb)->cb))
 
 /* Describe an entry in the "incomplete datagrams" queue. */
 struct ipq {
@@ -180,7 +181,7 @@ static void ip_evictor(struct net *net)
 
        evicted = inet_frag_evictor(&net->ipv4.frags, &ip4_frags);
        if (evicted)
-               IP_ADD_STATS_BH(IPSTATS_MIB_REASMFAILS, evicted);
+               IP_ADD_STATS_BH(net, IPSTATS_MIB_REASMFAILS, evicted);
 }
 
 /*
@@ -189,29 +190,53 @@ static void ip_evictor(struct net *net)
 static void ip_expire(unsigned long arg)
 {
        struct ipq *qp;
+       struct net *net;
 
        qp = container_of((struct inet_frag_queue *) arg, struct ipq, q);
+       net = container_of(qp->q.net, struct net, ipv4.frags);
 
        spin_lock(&qp->q.lock);
 
-       if (qp->q.last_in & COMPLETE)
+       if (qp->q.last_in & INET_FRAG_COMPLETE)
                goto out;
 
        ipq_kill(qp);
 
-       IP_INC_STATS_BH(IPSTATS_MIB_REASMTIMEOUT);
-       IP_INC_STATS_BH(IPSTATS_MIB_REASMFAILS);
+       IP_INC_STATS_BH(net, IPSTATS_MIB_REASMTIMEOUT);
+       IP_INC_STATS_BH(net, IPSTATS_MIB_REASMFAILS);
 
-       if ((qp->q.last_in&FIRST_IN) && qp->q.fragments != NULL) {
+       if ((qp->q.last_in & INET_FRAG_FIRST_IN) && qp->q.fragments != NULL) {
                struct sk_buff *head = qp->q.fragments;
-               struct net *net;
 
-               net = container_of(qp->q.net, struct net, ipv4.frags);
-               /* Send an ICMP "Fragment Reassembly Timeout" message. */
-               if ((head->dev = dev_get_by_index(net, qp->iif)) != NULL) {
-                       icmp_send(head, ICMP_TIME_EXCEEDED, ICMP_EXC_FRAGTIME, 0);
-                       dev_put(head->dev);
+               rcu_read_lock();
+               head->dev = dev_get_by_index_rcu(net, qp->iif);
+               if (!head->dev)
+                       goto out_rcu_unlock;
+
+               /*
+                * Only search router table for the head fragment,
+                * when defraging timeout at PRE_ROUTING HOOK.
+                */
+               if (qp->user == IP_DEFRAG_CONNTRACK_IN && !skb_dst(head)) {
+                       const struct iphdr *iph = ip_hdr(head);
+                       int err = ip_route_input(head, iph->daddr, iph->saddr,
+                                                iph->tos, head->dev);
+                       if (unlikely(err))
+                               goto out_rcu_unlock;
+
+                       /*
+                        * Only an end host needs to send an ICMP
+                        * "Fragment Reassembly Timeout" message, per RFC792.
+                        */
+                       if (skb_rtable(head)->rt_type != RTN_LOCAL)
+                               goto out_rcu_unlock;
+
                }
+
+               /* Send an ICMP "Fragment Reassembly Timeout" message. */
+               icmp_send(head, ICMP_TIME_EXCEEDED, ICMP_EXC_FRAGTIME, 0);
+out_rcu_unlock:
+               rcu_read_unlock();
        }
 out:
        spin_unlock(&qp->q.lock);
@@ -229,6 +254,8 @@ static inline struct ipq *ip_find(struct net *net, struct iphdr *iph, u32 user)
 
        arg.iph = iph;
        arg.user = user;
+
+       read_lock(&ip4_frags.lock);
        hash = ipqhashfn(iph->id, iph->saddr, iph->daddr, iph->protocol);
 
        q = inet_frag_find(&net->ipv4.frags, &ip4_frags, &arg, hash);
@@ -261,7 +288,10 @@ static inline int ip_frag_too_far(struct ipq *qp)
        rc = qp->q.fragments && (end - start) > max;
 
        if (rc) {
-               IP_INC_STATS_BH(IPSTATS_MIB_REASMFAILS);
+               struct net *net;
+
+               net = container_of(qp->q.net, struct net, ipv4.frags);
+               IP_INC_STATS_BH(net, IPSTATS_MIB_REASMFAILS);
        }
 
        return rc;
@@ -301,7 +331,7 @@ static int ip_frag_queue(struct ipq *qp, struct sk_buff *skb)
        int ihl, end;
        int err = -ENOENT;
 
-       if (qp->q.last_in & COMPLETE)
+       if (qp->q.last_in & INET_FRAG_COMPLETE)
                goto err;
 
        if (!(IPCB(skb)->flags & IPSKB_FRAG_COMPLETE) &&
@@ -327,9 +357,9 @@ static int ip_frag_queue(struct ipq *qp, struct sk_buff *skb)
                 * or have different end, the segment is corrrupted.
                 */
                if (end < qp->q.len ||
-                   ((qp->q.last_in & LAST_IN) && end != qp->q.len))
+                   ((qp->q.last_in & INET_FRAG_LAST_IN) && end != qp->q.len))
                        goto err;
-               qp->q.last_in |= LAST_IN;
+               qp->q.last_in |= INET_FRAG_LAST_IN;
                qp->q.len = end;
        } else {
                if (end&7) {
@@ -339,7 +369,7 @@ static int ip_frag_queue(struct ipq *qp, struct sk_buff *skb)
                }
                if (end > qp->q.len) {
                        /* Some bits beyond end -> corruption. */
-                       if (qp->q.last_in & LAST_IN)
+                       if (qp->q.last_in & INET_FRAG_LAST_IN)
                                goto err;
                        qp->q.len = end;
                }
@@ -438,9 +468,10 @@ static int ip_frag_queue(struct ipq *qp, struct sk_buff *skb)
        qp->q.meat += skb->len;
        atomic_add(skb->truesize, &qp->q.net->mem);
        if (offset == 0)
-               qp->q.last_in |= FIRST_IN;
+               qp->q.last_in |= INET_FRAG_FIRST_IN;
 
-       if (qp->q.last_in == (FIRST_IN | LAST_IN) && qp->q.meat == qp->q.len)
+       if (qp->q.last_in == (INET_FRAG_FIRST_IN | INET_FRAG_LAST_IN) &&
+           qp->q.meat == qp->q.len)
                return ip_frag_reasm(qp, prev, dev);
 
        write_lock(&ip4_frags.lock);
@@ -459,6 +490,7 @@ err:
 static int ip_frag_reasm(struct ipq *qp, struct sk_buff *prev,
                         struct net_device *dev)
 {
+       struct net *net = container_of(qp->q.net, struct net, ipv4.frags);
        struct iphdr *iph;
        struct sk_buff *fp, *head = qp->q.fragments;
        int len;
@@ -484,8 +516,8 @@ static int ip_frag_reasm(struct ipq *qp, struct sk_buff *prev,
                qp->q.fragments = head;
        }
 
-       BUG_TRAP(head != NULL);
-       BUG_TRAP(FRAG_CB(head)->offset == 0);
+       WARN_ON(head == NULL);
+       WARN_ON(FRAG_CB(head)->offset != 0);
 
        /* Allocate a new buffer for the datagram. */
        ihlen = ip_hdrlen(head);
@@ -502,7 +534,7 @@ static int ip_frag_reasm(struct ipq *qp, struct sk_buff *prev,
        /* If the first fragment is fragmented itself, we split
         * it to two chunks: the first with data and paged part
         * and the second, holding only fragments. */
-       if (skb_shinfo(head)->frag_list) {
+       if (skb_has_frags(head)) {
                struct sk_buff *clone;
                int i, plen = 0;
 
@@ -511,7 +543,7 @@ static int ip_frag_reasm(struct ipq *qp, struct sk_buff *prev,
                clone->next = head->next;
                head->next = clone;
                skb_shinfo(clone)->frag_list = skb_shinfo(head)->frag_list;
-               skb_shinfo(head)->frag_list = NULL;
+               skb_frag_list_init(head);
                for (i=0; i<skb_shinfo(head)->nr_frags; i++)
                        plen += skb_shinfo(head)->frags[i].size;
                clone->len = clone->data_len = head->data_len - plen;
@@ -544,7 +576,7 @@ static int ip_frag_reasm(struct ipq *qp, struct sk_buff *prev,
        iph = ip_hdr(head);
        iph->frag_off = 0;
        iph->tot_len = htons(len);
-       IP_INC_STATS_BH(IPSTATS_MIB_REASMOKS);
+       IP_INC_STATS_BH(net, IPSTATS_MIB_REASMOKS);
        qp->q.fragments = NULL;
        return 0;
 
@@ -555,11 +587,10 @@ out_nomem:
        goto out_fail;
 out_oversize:
        if (net_ratelimit())
-               printk(KERN_INFO
-                       "Oversized IP packet from %d.%d.%d.%d.\n",
-                       NIPQUAD(qp->saddr));
+               printk(KERN_INFO "Oversized IP packet from %pI4.\n",
+                       &qp->saddr);
 out_fail:
-       IP_INC_STATS_BH(IPSTATS_MIB_REASMFAILS);
+       IP_INC_STATS_BH(net, IPSTATS_MIB_REASMFAILS);
        return err;
 }
 
@@ -569,9 +600,9 @@ int ip_defrag(struct sk_buff *skb, u32 user)
        struct ipq *qp;
        struct net *net;
 
-       IP_INC_STATS_BH(IPSTATS_MIB_REASMREQDS);
+       net = skb->dev ? dev_net(skb->dev) : dev_net(skb_dst(skb)->dev);
+       IP_INC_STATS_BH(net, IPSTATS_MIB_REASMREQDS);
 
-       net = skb->dev ? skb->dev->nd_net : skb->dst->dev->nd_net;
        /* Start by cleaning up the memory. */
        if (atomic_read(&net->ipv4.frags.mem) > net->ipv4.frags.high_thresh)
                ip_evictor(net);
@@ -589,7 +620,7 @@ int ip_defrag(struct sk_buff *skb, u32 user)
                return ret;
        }
 
-       IP_INC_STATS_BH(IPSTATS_MIB_REASMFAILS);
+       IP_INC_STATS_BH(net, IPSTATS_MIB_REASMFAILS);
        kfree_skb(skb);
        return -ENOMEM;
 }
@@ -597,68 +628,64 @@ int ip_defrag(struct sk_buff *skb, u32 user)
 #ifdef CONFIG_SYSCTL
 static int zero;
 
-static struct ctl_table ip4_frags_ctl_table[] = {
+static struct ctl_table ip4_frags_ns_ctl_table[] = {
        {
-               .ctl_name       = NET_IPV4_IPFRAG_HIGH_THRESH,
                .procname       = "ipfrag_high_thresh",
                .data           = &init_net.ipv4.frags.high_thresh,
                .maxlen         = sizeof(int),
                .mode           = 0644,
-               .proc_handler   = &proc_dointvec
+               .proc_handler   = proc_dointvec
        },
        {
-               .ctl_name       = NET_IPV4_IPFRAG_LOW_THRESH,
                .procname       = "ipfrag_low_thresh",
                .data           = &init_net.ipv4.frags.low_thresh,
                .maxlen         = sizeof(int),
                .mode           = 0644,
-               .proc_handler   = &proc_dointvec
+               .proc_handler   = proc_dointvec
        },
        {
-               .ctl_name       = NET_IPV4_IPFRAG_TIME,
                .procname       = "ipfrag_time",
                .data           = &init_net.ipv4.frags.timeout,
                .maxlen         = sizeof(int),
                .mode           = 0644,
-               .proc_handler   = &proc_dointvec_jiffies,
-               .strategy       = &sysctl_jiffies
+               .proc_handler   = proc_dointvec_jiffies,
        },
+       { }
+};
+
+static struct ctl_table ip4_frags_ctl_table[] = {
        {
-               .ctl_name       = NET_IPV4_IPFRAG_SECRET_INTERVAL,
                .procname       = "ipfrag_secret_interval",
                .data           = &ip4_frags.secret_interval,
                .maxlen         = sizeof(int),
                .mode           = 0644,
-               .proc_handler   = &proc_dointvec_jiffies,
-               .strategy       = &sysctl_jiffies
+               .proc_handler   = proc_dointvec_jiffies,
        },
        {
                .procname       = "ipfrag_max_dist",
                .data           = &sysctl_ipfrag_max_dist,
                .maxlen         = sizeof(int),
                .mode           = 0644,
-               .proc_handler   = &proc_dointvec_minmax,
+               .proc_handler   = proc_dointvec_minmax,
                .extra1         = &zero
        },
        { }
 };
 
-static int ip4_frags_ctl_register(struct net *net)
+static int __net_init ip4_frags_ns_ctl_register(struct net *net)
 {
        struct ctl_table *table;
        struct ctl_table_header *hdr;
 
-       table = ip4_frags_ctl_table;
-       if (net != &init_net) {
-               table = kmemdup(table, sizeof(ip4_frags_ctl_table), GFP_KERNEL);
+       table = ip4_frags_ns_ctl_table;
+       if (!net_eq(net, &init_net)) {
+               table = kmemdup(table, sizeof(ip4_frags_ns_ctl_table), GFP_KERNEL);
                if (table == NULL)
                        goto err_alloc;
 
                table[0].data = &net->ipv4.frags.high_thresh;
                table[1].data = &net->ipv4.frags.low_thresh;
                table[2].data = &net->ipv4.frags.timeout;
-               table[3].mode &= ~0222;
-               table[4].mode &= ~0222;
        }
 
        hdr = register_net_sysctl_table(net, net_ipv4_ctl_path, table);
@@ -669,13 +696,13 @@ static int ip4_frags_ctl_register(struct net *net)
        return 0;
 
 err_reg:
-       if (net != &init_net)
+       if (!net_eq(net, &init_net))
                kfree(table);
 err_alloc:
        return -ENOMEM;
 }
 
-static void ip4_frags_ctl_unregister(struct net *net)
+static void __net_exit ip4_frags_ns_ctl_unregister(struct net *net)
 {
        struct ctl_table *table;
 
@@ -683,18 +710,27 @@ static void ip4_frags_ctl_unregister(struct net *net)
        unregister_net_sysctl_table(net->ipv4.frags_hdr);
        kfree(table);
 }
+
+static void ip4_frags_ctl_register(void)
+{
+       register_net_sysctl_rotable(net_ipv4_ctl_path, ip4_frags_ctl_table);
+}
 #else
-static inline int ip4_frags_ctl_register(struct net *net)
+static inline int ip4_frags_ns_ctl_register(struct net *net)
 {
        return 0;
 }
 
-static inline void ip4_frags_ctl_unregister(struct net *net)
+static inline void ip4_frags_ns_ctl_unregister(struct net *net)
+{
+}
+
+static inline void ip4_frags_ctl_register(void)
 {
 }
 #endif
 
-static int ipv4_frags_init_net(struct net *net)
+static int __net_init ipv4_frags_init_net(struct net *net)
 {
        /*
         * Fragment cache limits. We will commit 256K at one time. Should we
@@ -713,12 +749,12 @@ static int ipv4_frags_init_net(struct net *net)
 
        inet_frags_init_net(&net->ipv4.frags);
 
-       return ip4_frags_ctl_register(net);
+       return ip4_frags_ns_ctl_register(net);
 }
 
-static void ipv4_frags_exit_net(struct net *net)
+static void __net_exit ipv4_frags_exit_net(struct net *net)
 {
-       ip4_frags_ctl_unregister(net);
+       ip4_frags_ns_ctl_unregister(net);
        inet_frags_exit_net(&net->ipv4.frags, &ip4_frags);
 }
 
@@ -729,6 +765,7 @@ static struct pernet_operations ip4_frags_ops = {
 
 void __init ipfrag_init(void)
 {
+       ip4_frags_ctl_register();
        register_pernet_subsys(&ip4_frags_ops);
        ip4_frags.hashfn = ip4_hashfn;
        ip4_frags.constructor = ip4_frag_init;