Fedora kernel-2.6.17-1.2142_FC4 patched with stable patch-2.6.17.4-vs2.0.2-rc26.diff
[linux-2.6.git] / net / ipv6 / reassembly.c
index 59e7c63..eef985e 100644 (file)
@@ -74,7 +74,7 @@ struct ip6frag_skb_cb
 
 struct frag_queue
 {
-       struct frag_queue       *next;
+       struct hlist_node       list;
        struct list_head lru_list;              /* lru list member      */
 
        __u32                   id;             /* fragment id          */
@@ -95,14 +95,13 @@ struct frag_queue
 #define FIRST_IN               2
 #define LAST_IN                        1
        __u16                   nhoffset;
-       struct frag_queue       **pprev;
 };
 
 /* Hash table. */
 
 #define IP6Q_HASHSZ    64
 
-static struct frag_queue *ip6_frag_hash[IP6Q_HASHSZ];
+static struct hlist_head ip6_frag_hash[IP6Q_HASHSZ];
 static DEFINE_RWLOCK(ip6_frag_lock);
 static u32 ip6_frag_hash_rnd;
 static LIST_HEAD(ip6_frag_lru_list);
@@ -110,9 +109,7 @@ int ip6_frag_nqueues = 0;
 
 static __inline__ void __fq_unlink(struct frag_queue *fq)
 {
-       if(fq->next)
-               fq->next->pprev = fq->pprev;
-       *fq->pprev = fq->next;
+       hlist_del(&fq->list);
        list_del(&fq->lru_list);
        ip6_frag_nqueues--;
 }
@@ -124,6 +121,10 @@ static __inline__ void fq_unlink(struct frag_queue *fq)
        write_unlock(&ip6_frag_lock);
 }
 
+/*
+ * callers should be careful not to use the hash value outside the ipfrag_lock
+ * as doing so could race with ipfrag_hash_rnd being recalculated.
+ */
 static unsigned int ip6qhashfn(u32 id, struct in6_addr *saddr,
                               struct in6_addr *daddr)
 {
@@ -163,28 +164,21 @@ static void ip6_frag_secret_rebuild(unsigned long dummy)
        get_random_bytes(&ip6_frag_hash_rnd, sizeof(u32));
        for (i = 0; i < IP6Q_HASHSZ; i++) {
                struct frag_queue *q;
+               struct hlist_node *p, *n;
 
-               q = ip6_frag_hash[i];
-               while (q) {
-                       struct frag_queue *next = q->next;
+               hlist_for_each_entry_safe(q, p, n, &ip6_frag_hash[i], list) {
                        unsigned int hval = ip6qhashfn(q->id,
                                                       &q->saddr,
                                                       &q->daddr);
 
                        if (hval != i) {
-                               /* Unlink. */
-                               if (q->next)
-                                       q->next->pprev = q->pprev;
-                               *q->pprev = q->next;
+                               hlist_del(&q->list);
 
                                /* Relink to new hash chain. */
-                               if ((q->next = ip6_frag_hash[hval]) != NULL)
-                                       q->next->pprev = &q->next;
-                               ip6_frag_hash[hval] = q;
-                               q->pprev = &ip6_frag_hash[hval];
-                       }
+                               hlist_add_head(&q->list,
+                                              &ip6_frag_hash[hval]);
 
-                       q = next;
+                       }
                }
        }
        write_unlock(&ip6_frag_lock);
@@ -213,7 +207,7 @@ static inline void frag_free_queue(struct frag_queue *fq, int *work)
 
 static inline struct frag_queue *frag_alloc_queue(void)
 {
-       struct frag_queue *fq = kmalloc(sizeof(struct frag_queue), GFP_ATOMIC);
+       struct frag_queue *fq = kzalloc(sizeof(struct frag_queue), GFP_ATOMIC);
 
        if(!fq)
                return NULL;
@@ -298,6 +292,7 @@ static void ip6_evictor(void)
 static void ip6_frag_expire(unsigned long data)
 {
        struct frag_queue *fq = (struct frag_queue *) data;
+       struct net_device *dev;
 
        spin_lock(&fq->lock);
 
@@ -309,22 +304,22 @@ static void ip6_frag_expire(unsigned long data)
        IP6_INC_STATS_BH(IPSTATS_MIB_REASMTIMEOUT);
        IP6_INC_STATS_BH(IPSTATS_MIB_REASMFAILS);
 
-       /* Send error only if the first segment arrived. */
-       if (fq->last_in&FIRST_IN && fq->fragments) {
-               struct net_device *dev = dev_get_by_index(fq->iif);
+       /* Don't send error if the first segment did not arrive. */
+       if (!(fq->last_in&FIRST_IN) || !fq->fragments)
+               goto out;
 
-               /*
-                  But use as source device on which LAST ARRIVED
-                  segment was received. And do not use fq->dev
-                  pointer directly, device might already disappeared.
-                */
-               if (dev) {
-                       fq->fragments->dev = dev;
-                       icmpv6_send(fq->fragments, ICMPV6_TIME_EXCEED, ICMPV6_EXC_FRAGTIME, 0,
-                                   dev);
-                       dev_put(dev);
-               }
-       }
+       dev = dev_get_by_index(fq->iif);
+       if (!dev)
+               goto out;
+
+       /*
+          But use as source device on which LAST ARRIVED
+          segment was received. And do not use fq->dev
+          pointer directly, device might already disappeared.
+        */
+       fq->fragments->dev = dev;
+       icmpv6_send(fq->fragments, ICMPV6_TIME_EXCEED, ICMPV6_EXC_FRAGTIME, 0, dev);
+       dev_put(dev);
 out:
        spin_unlock(&fq->lock);
        fq_put(fq, NULL);
@@ -333,14 +328,18 @@ out:
 /* Creation primitives. */
 
 
-static struct frag_queue *ip6_frag_intern(unsigned int hash,
-                                         struct frag_queue *fq_in)
+static struct frag_queue *ip6_frag_intern(struct frag_queue *fq_in)
 {
        struct frag_queue *fq;
+       unsigned int hash;
+#ifdef CONFIG_SMP
+       struct hlist_node *n;
+#endif
 
        write_lock(&ip6_frag_lock);
+       hash = ip6qhashfn(fq_in->id, &fq_in->saddr, &fq_in->daddr);
 #ifdef CONFIG_SMP
-       for (fq = ip6_frag_hash[hash]; fq; fq = fq->next) {
+       hlist_for_each_entry(fq, n, &ip6_frag_hash[hash], list) {
                if (fq->id == fq_in->id && 
                    ipv6_addr_equal(&fq_in->saddr, &fq->saddr) &&
                    ipv6_addr_equal(&fq_in->daddr, &fq->daddr)) {
@@ -358,10 +357,7 @@ static struct frag_queue *ip6_frag_intern(unsigned int hash,
                atomic_inc(&fq->refcnt);
 
        atomic_inc(&fq->refcnt);
-       if((fq->next = ip6_frag_hash[hash]) != NULL)
-               fq->next->pprev = &fq->next;
-       ip6_frag_hash[hash] = fq;
-       fq->pprev = &ip6_frag_hash[hash];
+       hlist_add_head(&fq->list, &ip6_frag_hash[hash]);
        INIT_LIST_HEAD(&fq->lru_list);
        list_add_tail(&fq->lru_list, &ip6_frag_lru_list);
        ip6_frag_nqueues++;
@@ -371,15 +367,13 @@ static struct frag_queue *ip6_frag_intern(unsigned int hash,
 
 
 static struct frag_queue *
-ip6_frag_create(unsigned int hash, u32 id, struct in6_addr *src, struct in6_addr *dst)
+ip6_frag_create(u32 id, struct in6_addr *src, struct in6_addr *dst)
 {
        struct frag_queue *fq;
 
        if ((fq = frag_alloc_queue()) == NULL)
                goto oom;
 
-       memset(fq, 0, sizeof(struct frag_queue));
-
        fq->id = id;
        ipv6_addr_copy(&fq->saddr, src);
        ipv6_addr_copy(&fq->daddr, dst);
@@ -390,7 +384,7 @@ ip6_frag_create(unsigned int hash, u32 id, struct in6_addr *src, struct in6_addr
        spin_lock_init(&fq->lock);
        atomic_set(&fq->refcnt, 1);
 
-       return ip6_frag_intern(hash, fq);
+       return ip6_frag_intern(fq);
 
 oom:
        IP6_INC_STATS_BH(IPSTATS_MIB_REASMFAILS);
@@ -401,10 +395,12 @@ static __inline__ struct frag_queue *
 fq_find(u32 id, struct in6_addr *src, struct in6_addr *dst)
 {
        struct frag_queue *fq;
-       unsigned int hash = ip6qhashfn(id, src, dst);
+       struct hlist_node *n;
+       unsigned int hash;
 
        read_lock(&ip6_frag_lock);
-       for(fq = ip6_frag_hash[hash]; fq; fq = fq->next) {
+       hash = ip6qhashfn(id, src, dst);
+       hlist_for_each_entry(fq, n, &ip6_frag_hash[hash], list) {
                if (fq->id == id && 
                    ipv6_addr_equal(src, &fq->saddr) &&
                    ipv6_addr_equal(dst, &fq->daddr)) {
@@ -415,7 +411,7 @@ fq_find(u32 id, struct in6_addr *src, struct in6_addr *dst)
        }
        read_unlock(&ip6_frag_lock);
 
-       return ip6_frag_create(hash, id, src, dst);
+       return ip6_frag_create(id, src, dst);
 }
 
 
@@ -479,12 +475,9 @@ static void ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb,
        /* Point into the IP datagram 'data' part. */
        if (!pskb_pull(skb, (u8 *) (fhdr + 1) - skb->data))
                goto err;
-       if (end-offset < skb->len) {
-               if (pskb_trim(skb, end - offset))
-                       goto err;
-               if (skb->ip_summed != CHECKSUM_UNNECESSARY)
-                       skb->ip_summed = CHECKSUM_NONE;
-       }
+       
+       if (pskb_trim_rcsum(skb, end - offset))
+               goto err;
 
        /* Find out which fragments are in front and at the back of us
         * in the chain of fragments so far.  We must know where to put
@@ -562,7 +555,7 @@ static void ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb,
        if (skb->dev)
                fq->iif = skb->dev->ifindex;
        skb->dev = NULL;
-       fq->stamp = skb->stamp;
+       skb_get_timestamp(skb, &fq->stamp);
        fq->meat += skb->len;
        atomic_add(skb->truesize, &ip6_frag_mem);
 
@@ -593,7 +586,6 @@ err:
  *     the last and the first frames arrived and all the bits are here.
  */
 static int ip6_frag_reasm(struct frag_queue *fq, struct sk_buff **skb_in,
-                         unsigned int *nhoffp,
                          struct net_device *dev)
 {
        struct sk_buff *fp, *head = fq->fragments;
@@ -664,8 +656,9 @@ static int ip6_frag_reasm(struct frag_queue *fq, struct sk_buff **skb_in,
 
        head->next = NULL;
        head->dev = dev;
-       head->stamp = fq->stamp;
+       skb_set_timestamp(head, &fq->stamp);
        head->nh.ipv6h->payload_len = htons(payload_len);
+       IP6CB(head)->nhoff = nhoff;
 
        *skb_in = head;
 
@@ -675,7 +668,6 @@ static int ip6_frag_reasm(struct frag_queue *fq, struct sk_buff **skb_in,
 
        IP6_INC_STATS_BH(IPSTATS_MIB_REASMOKS);
        fq->fragments = NULL;
-       *nhoffp = nhoff;
        return 1;
 
 out_oversize:
@@ -690,7 +682,7 @@ out_fail:
        return -1;
 }
 
-static int ipv6_frag_rcv(struct sk_buff **skbp, unsigned int *nhoffp)
+static int ipv6_frag_rcv(struct sk_buff **skbp)
 {
        struct sk_buff *skb = *skbp; 
        struct net_device *dev = skb->dev;
@@ -722,7 +714,7 @@ static int ipv6_frag_rcv(struct sk_buff **skbp, unsigned int *nhoffp)
                skb->h.raw += sizeof(struct frag_hdr);
                IP6_INC_STATS_BH(IPSTATS_MIB_REASMOKS);
 
-               *nhoffp = (u8*)fhdr - skb->nh.raw;
+               IP6CB(skb)->nhoff = (u8*)fhdr - skb->nh.raw;
                return 1;
        }
 
@@ -734,11 +726,11 @@ static int ipv6_frag_rcv(struct sk_buff **skbp, unsigned int *nhoffp)
 
                spin_lock(&fq->lock);
 
-               ip6_frag_queue(fq, skb, fhdr, *nhoffp);
+               ip6_frag_queue(fq, skb, fhdr, IP6CB(skb)->nhoff);
 
                if (fq->last_in == (FIRST_IN|LAST_IN) &&
                    fq->meat == fq->len)
-                       ret = ip6_frag_reasm(fq, skbp, nhoffp, dev);
+                       ret = ip6_frag_reasm(fq, skbp, dev);
 
                spin_unlock(&fq->lock);
                fq_put(fq, NULL);