X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=net%2Fsctp%2Finput.c;h=33111873a488eaf78b63907d73da6ce6ad9cc9fd;hb=refs%2Fheads%2Fvserver;hp=2325fee8574819498067979aef55bfcd353c9a0a;hpb=76828883507a47dae78837ab5dec5a5b4513c667;p=linux-2.6.git diff --git a/net/sctp/input.c b/net/sctp/input.c index 2325fee85..33111873a 100644 --- a/net/sctp/input.c +++ b/net/sctp/input.c @@ -73,6 +73,8 @@ static struct sctp_association *__sctp_lookup_association( const union sctp_addr *peer, struct sctp_transport **pt); +static void sctp_add_backlog(struct sock *sk, struct sk_buff *skb); + /* Calculate the SCTP checksum of an SCTP packet. */ static inline int sctp_rcv_checksum(struct sk_buff *skb) @@ -127,14 +129,13 @@ int sctp_rcv(struct sk_buff *skb) union sctp_addr dest; int family; struct sctp_af *af; - int ret = 0; if (skb->pkt_type!=PACKET_HOST) goto discard_it; SCTP_INC_STATS_BH(SCTP_MIB_INSCTPPACKS); - if (skb_linearize(skb, GFP_ATOMIC)) + if (skb_linearize(skb)) goto discard_it; sh = (struct sctphdr *) skb->h.raw; @@ -143,7 +144,8 @@ int sctp_rcv(struct sk_buff *skb) __skb_pull(skb, skb->h.raw - skb->data); if (skb->len < sizeof(struct sctphdr)) goto discard_it; - if (sctp_rcv_checksum(skb) < 0) + if ((skb->ip_summed != CHECKSUM_UNNECESSARY) && + (sctp_rcv_checksum(skb) < 0)) goto discard_it; skb_pull(skb, sizeof(struct sctphdr)); @@ -191,7 +193,6 @@ int sctp_rcv(struct sk_buff *skb) */ if (sk->sk_bound_dev_if && (sk->sk_bound_dev_if != af->skb_iif(skb))) { - sock_put(sk); if (asoc) { sctp_association_put(asoc); asoc = NULL; @@ -202,7 +203,6 @@ int sctp_rcv(struct sk_buff *skb) sk = sctp_get_ctl_sock(); ep = sctp_sk(sk)->ep; sctp_endpoint_hold(ep); - sock_hold(sk); rcvr = &ep->base; } @@ -221,26 +221,17 @@ int sctp_rcv(struct sk_buff *skb) } } - /* SCTP seems to always need a timestamp right now (FIXME) */ - if (skb->tstamp.off_sec == 0) { - __net_timestamp(skb); - sock_enable_timestamp(sk); - } - if (!xfrm_policy_check(sk, XFRM_POLICY_IN, skb, family)) goto discard_release; nf_reset(skb); - ret = sk_filter(sk, skb, 1); - if (ret) + if (sk_filter(sk, skb)) goto discard_release; /* Create an SCTP packet structure. */ chunk = sctp_chunkify(skb, asoc, sk); - if (!chunk) { - ret = -ENOMEM; + if (!chunk) goto discard_release; - } SCTP_INPUT_CB(skb)->chunk = chunk; /* Remember what endpoint is to handle this packet. */ @@ -261,35 +252,31 @@ int sctp_rcv(struct sk_buff *skb) */ sctp_bh_lock_sock(sk); - /* It is possible that the association could have moved to a different - * socket if it is peeled off. If so, update the sk. - */ - if (sk != rcvr->sk) { - sctp_bh_lock_sock(rcvr->sk); - sctp_bh_unlock_sock(sk); - sk = rcvr->sk; + if (sock_owned_by_user(sk)) { + SCTP_INC_STATS_BH(SCTP_MIB_IN_PKT_BACKLOG); + sctp_add_backlog(sk, skb); + } else { + SCTP_INC_STATS_BH(SCTP_MIB_IN_PKT_SOFTIRQ); + sctp_inq_push(&chunk->rcvr->inqueue, chunk); } - if (sock_owned_by_user(sk)) - sk_add_backlog(sk, skb); - else - sctp_backlog_rcv(sk, skb); - - /* Release the sock and the sock ref we took in the lookup calls. - * The asoc/ep ref will be released in sctp_backlog_rcv. - */ sctp_bh_unlock_sock(sk); - sock_put(sk); - return ret; + /* Release the asoc/ep ref we took in the lookup calls. */ + if (asoc) + sctp_association_put(asoc); + else + sctp_endpoint_put(ep); + + return 0; discard_it: + SCTP_INC_STATS_BH(SCTP_MIB_IN_PKT_DISCARDS); kfree_skb(skb); - return ret; + return 0; discard_release: - /* Release any structures we may be holding. */ - sock_put(sk); + /* Release the asoc/ep ref we took in the lookup calls. */ if (asoc) sctp_association_put(asoc); else @@ -298,56 +285,87 @@ discard_release: goto discard_it; } -/* Handle second half of inbound skb processing. If the sock was busy, - * we may have need to delay processing until later when the sock is - * released (on the backlog). If not busy, we call this routine - * directly from the bottom half. +/* Process the backlog queue of the socket. Every skb on + * the backlog holds a ref on an association or endpoint. + * We hold this ref throughout the state machine to make + * sure that the structure we need is still around. */ int sctp_backlog_rcv(struct sock *sk, struct sk_buff *skb) { struct sctp_chunk *chunk = SCTP_INPUT_CB(skb)->chunk; - struct sctp_inq *inqueue = NULL; + struct sctp_inq *inqueue = &chunk->rcvr->inqueue; struct sctp_ep_common *rcvr = NULL; + int backloged = 0; rcvr = chunk->rcvr; - BUG_TRAP(rcvr->sk == sk); - - if (rcvr->dead) { - sctp_chunk_free(chunk); - } else { - inqueue = &chunk->rcvr->inqueue; - sctp_inq_push(inqueue, chunk); - } - - /* Release the asoc/ep ref we took in the lookup calls in sctp_rcv. */ - if (SCTP_EP_TYPE_ASSOCIATION == rcvr->type) - sctp_association_put(sctp_assoc(rcvr)); - else - sctp_endpoint_put(sctp_ep(rcvr)); - + /* If the rcvr is dead then the association or endpoint + * has been deleted and we can safely drop the chunk + * and refs that we are holding. + */ + if (rcvr->dead) { + sctp_chunk_free(chunk); + goto done; + } + + if (unlikely(rcvr->sk != sk)) { + /* In this case, the association moved from one socket to + * another. We are currently sitting on the backlog of the + * old socket, so we need to move. + * However, since we are here in the process context we + * need to take make sure that the user doesn't own + * the new socket when we process the packet. + * If the new socket is user-owned, queue the chunk to the + * backlog of the new socket without dropping any refs. + * Otherwise, we can safely push the chunk on the inqueue. + */ + + sk = rcvr->sk; + sctp_bh_lock_sock(sk); + + if (sock_owned_by_user(sk)) { + sk_add_backlog(sk, skb); + backloged = 1; + } else + sctp_inq_push(inqueue, chunk); + + sctp_bh_unlock_sock(sk); + + /* If the chunk was backloged again, don't drop refs */ + if (backloged) + return 0; + } else { + sctp_inq_push(inqueue, chunk); + } + +done: + /* Release the refs we took in sctp_add_backlog */ + if (SCTP_EP_TYPE_ASSOCIATION == rcvr->type) + sctp_association_put(sctp_assoc(rcvr)); + else if (SCTP_EP_TYPE_SOCKET == rcvr->type) + sctp_endpoint_put(sctp_ep(rcvr)); + else + BUG(); + return 0; } -void sctp_backlog_migrate(struct sctp_association *assoc, - struct sock *oldsk, struct sock *newsk) +static void sctp_add_backlog(struct sock *sk, struct sk_buff *skb) { - struct sk_buff *skb; - struct sctp_chunk *chunk; + struct sctp_chunk *chunk = SCTP_INPUT_CB(skb)->chunk; + struct sctp_ep_common *rcvr = chunk->rcvr; - skb = oldsk->sk_backlog.head; - oldsk->sk_backlog.head = oldsk->sk_backlog.tail = NULL; - while (skb != NULL) { - struct sk_buff *next = skb->next; - - chunk = SCTP_INPUT_CB(skb)->chunk; - skb->next = NULL; - if (&assoc->base == chunk->rcvr) - sk_add_backlog(newsk, skb); - else - sk_add_backlog(oldsk, skb); - skb = next; - } + /* Hold the assoc/ep while hanging on the backlog queue. + * This way, we know structures we need will not disappear from us + */ + if (SCTP_EP_TYPE_ASSOCIATION == rcvr->type) + sctp_association_hold(sctp_assoc(rcvr)); + else if (SCTP_EP_TYPE_SOCKET == rcvr->type) + sctp_endpoint_hold(sctp_ep(rcvr)); + else + BUG(); + + sk_add_backlog(sk, skb); } /* Handle icmp frag needed error. */ @@ -367,7 +385,7 @@ void sctp_icmp_frag_needed(struct sock *sk, struct sctp_association *asoc, * pmtu discovery on this transport. */ t->pathmtu = SCTP_DEFAULT_MINSEGMENT; - t->param_flags = (t->param_flags & ~SPP_HB) | + t->param_flags = (t->param_flags & ~SPP_PMTUD) | SPP_PMTUD_DISABLE; } else { t->pathmtu = pmtu; @@ -420,7 +438,7 @@ struct sock *sctp_err_lookup(int family, struct sk_buff *skb, union sctp_addr daddr; struct sctp_af *af; struct sock *sk = NULL; - struct sctp_association *asoc = NULL; + struct sctp_association *asoc; struct sctp_transport *transport = NULL; *app = NULL; *tpp = NULL; @@ -461,7 +479,6 @@ struct sock *sctp_err_lookup(int family, struct sk_buff *skb, return sk; out: - sock_put(sk); if (asoc) sctp_association_put(asoc); return NULL; @@ -471,7 +488,6 @@ out: void sctp_err_finish(struct sock *sk, struct sctp_association *asoc) { sctp_bh_unlock_sock(sk); - sock_put(sk); if (asoc) sctp_association_put(asoc); } @@ -498,7 +514,7 @@ void sctp_v4_err(struct sk_buff *skb, __u32 info) int type = skb->h.icmph->type; int code = skb->h.icmph->code; struct sock *sk; - struct sctp_association *asoc; + struct sctp_association *asoc = NULL; struct sctp_transport *transport; struct inet_sock *inet; char *saveip, *savesctp; @@ -710,7 +726,7 @@ static struct sctp_endpoint *__sctp_rcv_lookup_endpoint(const union sctp_addr *l struct sctp_endpoint *ep; int hash; - hash = sctp_ep_hashfn(laddr->v4.sin_port); + hash = sctp_ep_hashfn(ntohs(laddr->v4.sin_port)); head = &sctp_ep_hashtable[hash]; read_lock(&head->lock); for (epb = head->chain; epb; epb = epb->next) { @@ -724,7 +740,6 @@ static struct sctp_endpoint *__sctp_rcv_lookup_endpoint(const union sctp_addr *l hit: sctp_endpoint_hold(ep); - sock_hold(epb->sk); read_unlock(&head->lock); return ep; } @@ -756,6 +771,9 @@ static void __sctp_hash_established(struct sctp_association *asoc) /* Add an association to the hash. Local BH-safe. */ void sctp_hash_established(struct sctp_association *asoc) { + if (asoc->temp) + return; + sctp_local_bh_disable(); __sctp_hash_established(asoc); sctp_local_bh_enable(); @@ -789,6 +807,9 @@ static void __sctp_unhash_established(struct sctp_association *asoc) /* Remove association from the hash table. Local BH-safe. */ void sctp_unhash_established(struct sctp_association *asoc) { + if (asoc->temp) + return; + sctp_local_bh_disable(); __sctp_unhash_established(asoc); sctp_local_bh_enable(); @@ -809,7 +830,7 @@ static struct sctp_association *__sctp_lookup_association( /* Optimize here for direct hit, only listening connections can * have wildcards anyways. */ - hash = sctp_assoc_hashfn(local->v4.sin_port, peer->v4.sin_port); + hash = sctp_assoc_hashfn(ntohs(local->v4.sin_port), ntohs(peer->v4.sin_port)); head = &sctp_assoc_hashtable[hash]; read_lock(&head->lock); for (epb = head->chain; epb; epb = epb->next) { @@ -826,7 +847,6 @@ static struct sctp_association *__sctp_lookup_association( hit: *pt = transport; sctp_association_hold(asoc); - sock_hold(epb->sk); read_unlock(&head->lock); return asoc; } @@ -854,7 +874,6 @@ int sctp_has_association(const union sctp_addr *laddr, struct sctp_transport *transport; if ((asoc = sctp_lookup_association(laddr, paddr, &transport))) { - sock_put(asoc->base.sk); sctp_association_put(asoc); return 1; } @@ -938,7 +957,7 @@ static struct sctp_association *__sctp_rcv_init_lookup(struct sk_buff *skb, if (!af) continue; - af->from_addr_param(paddr, params.addr, ntohs(sh->source), 0); + af->from_addr_param(paddr, params.addr, sh->source, 0); asoc = __sctp_lookup_association(laddr, paddr, &transport); if (asoc)