From 8de8c8738086501bbe3057ed6f4b70dded657488 Mon Sep 17 00:00:00 2001 From: Sridhar Samudrala Date: Fri, 19 May 2006 10:58:12 -0700 Subject: [PATCH 1/5] [SCTP]: Set sk_err so that poll wakes up after a non-blocking connect failure. Also fix some other cases where sk_err is not set for 1-1 style sockets. Signed-off-by: Sridhar Samudrala --- include/net/sctp/command.h | 1 + net/sctp/input.c | 4 +- net/sctp/sm_sideeffect.c | 16 ++++++-- net/sctp/sm_statefuns.c | 75 ++++++++++++++++++++++++-------------- net/sctp/socket.c | 1 + 5 files changed, 64 insertions(+), 33 deletions(-) diff --git a/include/net/sctp/command.h b/include/net/sctp/command.h index 34a1a09e5aef..807d6f1ef4b5 100644 --- a/include/net/sctp/command.h +++ b/include/net/sctp/command.h @@ -99,6 +99,7 @@ typedef enum { SCTP_CMD_DEL_NON_PRIMARY, /* Removes non-primary peer transports. */ SCTP_CMD_T3_RTX_TIMERS_STOP, /* Stops T3-rtx pending timers */ SCTP_CMD_FORCE_PRIM_RETRAN, /* Forces retrans. over primary path. */ + SCTP_CMD_SET_SK_ERR, /* Set sk_err */ SCTP_CMD_LAST } sctp_verb_t; diff --git a/net/sctp/input.c b/net/sctp/input.c index d117ebc75cf8..7523f4df2da6 100644 --- a/net/sctp/input.c +++ b/net/sctp/input.c @@ -412,7 +412,7 @@ 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; @@ -490,7 +490,7 @@ 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; diff --git a/net/sctp/sm_sideeffect.c b/net/sctp/sm_sideeffect.c index 8d1dc24bab4c..c5beb2ad7ef7 100644 --- a/net/sctp/sm_sideeffect.c +++ b/net/sctp/sm_sideeffect.c @@ -498,10 +498,6 @@ static void sctp_cmd_assoc_failed(sctp_cmd_seq_t *commands, sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, SCTP_STATE(SCTP_STATE_CLOSED)); - /* Set sk_err to ECONNRESET on a 1-1 style socket. */ - if (!sctp_style(asoc->base.sk, UDP)) - asoc->base.sk->sk_err = ECONNRESET; - /* SEND_FAILED sent later when cleaning up the association. */ asoc->outqueue.error = error; sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); @@ -838,6 +834,15 @@ static void sctp_cmd_del_non_primary(struct sctp_association *asoc) return; } +/* Helper function to set sk_err on a 1-1 style socket. */ +static void sctp_cmd_set_sk_err(struct sctp_association *asoc, int error) +{ + struct sock *sk = asoc->base.sk; + + if (!sctp_style(sk, UDP)) + sk->sk_err = error; +} + /* These three macros allow us to pull the debugging code out of the * main flow of sctp_do_sm() to keep attention focused on the real * functionality there. @@ -1458,6 +1463,9 @@ static int sctp_cmd_interpreter(sctp_event_t event_type, local_cork = 0; asoc->peer.retran_path = t; break; + case SCTP_CMD_SET_SK_ERR: + sctp_cmd_set_sk_err(asoc, cmd->obj.error); + break; default: printk(KERN_WARNING "Impossible command: %u, %p\n", cmd->verb, cmd->obj.ptr); diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c index 8cdba51ec076..174f7a7c6cd1 100644 --- a/net/sctp/sm_statefuns.c +++ b/net/sctp/sm_statefuns.c @@ -93,7 +93,7 @@ static sctp_disposition_t sctp_sf_shut_8_4_5(const struct sctp_endpoint *ep, static struct sctp_sackhdr *sctp_sm_pull_sack(struct sctp_chunk *chunk); static sctp_disposition_t sctp_stop_t1_and_abort(sctp_cmd_seq_t *commands, - __u16 error, + __u16 error, int sk_err, const struct sctp_association *asoc, struct sctp_transport *transport); @@ -448,7 +448,7 @@ sctp_disposition_t sctp_sf_do_5_1C_ack(const struct sctp_endpoint *ep, __u32 init_tag; struct sctp_chunk *err_chunk; struct sctp_packet *packet; - sctp_disposition_t ret; + __u16 error; if (!sctp_vtag_verify(chunk, asoc)) return sctp_sf_pdiscard(ep, asoc, type, arg, commands); @@ -480,11 +480,9 @@ sctp_disposition_t sctp_sf_do_5_1C_ack(const struct sctp_endpoint *ep, goto nomem; sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); - sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, - SCTP_STATE(SCTP_STATE_CLOSED)); - SCTP_INC_STATS(SCTP_MIB_ABORTEDS); - sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); - return SCTP_DISPOSITION_DELETE_TCB; + return sctp_stop_t1_and_abort(commands, SCTP_ERROR_INV_PARAM, + ECONNREFUSED, asoc, + chunk->transport); } /* Verify the INIT chunk before processing it. */ @@ -511,27 +509,16 @@ sctp_disposition_t sctp_sf_do_5_1C_ack(const struct sctp_endpoint *ep, sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, SCTP_PACKET(packet)); SCTP_INC_STATS(SCTP_MIB_OUTCTRLCHUNKS); - sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, - SCTP_STATE(SCTP_STATE_CLOSED)); - sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, - SCTP_NULL()); - return SCTP_DISPOSITION_CONSUME; + error = SCTP_ERROR_INV_PARAM; } else { - sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, - SCTP_STATE(SCTP_STATE_CLOSED)); - sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, - SCTP_NULL()); - return SCTP_DISPOSITION_NOMEM; + error = SCTP_ERROR_NO_RESOURCE; } } else { - ret = sctp_sf_tabort_8_4_8(ep, asoc, type, arg, - commands); - sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, - SCTP_STATE(SCTP_STATE_CLOSED)); - sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, - SCTP_NULL()); - return ret; + sctp_sf_tabort_8_4_8(ep, asoc, type, arg, commands); + error = SCTP_ERROR_INV_PARAM; } + return sctp_stop_t1_and_abort(commands, error, ECONNREFUSED, + asoc, chunk->transport); } /* Tag the variable length parameters. Note that we never @@ -886,6 +873,8 @@ sctp_disposition_t sctp_sf_sendbeat_8_3(const struct sctp_endpoint *ep, struct sctp_transport *transport = (struct sctp_transport *) arg; if (asoc->overall_error_count >= asoc->max_retrans) { + sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, + SCTP_ERROR(ETIMEDOUT)); /* CMD_ASSOC_FAILED calls CMD_DELETE_TCB. */ sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, SCTP_U32(SCTP_ERROR_NO_ERROR)); @@ -2126,6 +2115,8 @@ static sctp_disposition_t sctp_sf_do_5_2_6_stale(const struct sctp_endpoint *ep, int attempts = asoc->init_err_counter + 1; if (attempts > asoc->max_init_attempts) { + sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, + SCTP_ERROR(ETIMEDOUT)); sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED, SCTP_U32(SCTP_ERROR_STALE_COOKIE)); return SCTP_DISPOSITION_DELETE_TCB; @@ -2262,6 +2253,7 @@ sctp_disposition_t sctp_sf_do_9_1_abort(const struct sctp_endpoint *ep, if (len >= sizeof(struct sctp_chunkhdr) + sizeof(struct sctp_errhdr)) error = ((sctp_errhdr_t *)chunk->skb->data)->cause; + sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, SCTP_ERROR(ECONNRESET)); /* ASSOC_FAILED will DELETE_TCB. */ sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, SCTP_U32(error)); SCTP_INC_STATS(SCTP_MIB_ABORTEDS); @@ -2306,7 +2298,8 @@ sctp_disposition_t sctp_sf_cookie_wait_abort(const struct sctp_endpoint *ep, if (len >= sizeof(struct sctp_chunkhdr) + sizeof(struct sctp_errhdr)) error = ((sctp_errhdr_t *)chunk->skb->data)->cause; - return sctp_stop_t1_and_abort(commands, error, asoc, chunk->transport); + return sctp_stop_t1_and_abort(commands, error, ECONNREFUSED, asoc, + chunk->transport); } /* @@ -2318,7 +2311,8 @@ sctp_disposition_t sctp_sf_cookie_wait_icmp_abort(const struct sctp_endpoint *ep void *arg, sctp_cmd_seq_t *commands) { - return sctp_stop_t1_and_abort(commands, SCTP_ERROR_NO_ERROR, asoc, + return sctp_stop_t1_and_abort(commands, SCTP_ERROR_NO_ERROR, + ENOPROTOOPT, asoc, (struct sctp_transport *)arg); } @@ -2343,7 +2337,7 @@ sctp_disposition_t sctp_sf_cookie_echoed_abort(const struct sctp_endpoint *ep, * This is common code called by several sctp_sf_*_abort() functions above. */ static sctp_disposition_t sctp_stop_t1_and_abort(sctp_cmd_seq_t *commands, - __u16 error, + __u16 error, int sk_err, const struct sctp_association *asoc, struct sctp_transport *transport) { @@ -2353,6 +2347,7 @@ static sctp_disposition_t sctp_stop_t1_and_abort(sctp_cmd_seq_t *commands, SCTP_INC_STATS(SCTP_MIB_ABORTEDS); sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); + sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, SCTP_ERROR(sk_err)); /* CMD_INIT_FAILED will DELETE_TCB. */ sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED, SCTP_U32(error)); @@ -3336,6 +3331,8 @@ sctp_disposition_t sctp_sf_do_asconf_ack(const struct sctp_endpoint *ep, sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO)); sctp_add_cmd_sf(commands, SCTP_CMD_DISCARD_PACKET,SCTP_NULL()); + sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, + SCTP_ERROR(ECONNABORTED)); sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, SCTP_U32(SCTP_ERROR_ASCONF_ACK)); SCTP_INC_STATS(SCTP_MIB_ABORTEDS); @@ -3362,6 +3359,8 @@ sctp_disposition_t sctp_sf_do_asconf_ack(const struct sctp_endpoint *ep, * processing the rest of the chunks in the packet. */ sctp_add_cmd_sf(commands, SCTP_CMD_DISCARD_PACKET,SCTP_NULL()); + sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, + SCTP_ERROR(ECONNABORTED)); sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, SCTP_U32(SCTP_ERROR_ASCONF_ACK)); SCTP_INC_STATS(SCTP_MIB_ABORTEDS); @@ -3714,9 +3713,13 @@ static sctp_disposition_t sctp_sf_violation_chunklen( if (asoc->state <= SCTP_STATE_COOKIE_ECHOED) { sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); + sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, + SCTP_ERROR(ECONNREFUSED)); sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED, SCTP_U32(SCTP_ERROR_PROTO_VIOLATION)); } else { + sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, + SCTP_ERROR(ECONNABORTED)); sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, SCTP_U32(SCTP_ERROR_PROTO_VIOLATION)); SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); @@ -4034,6 +4037,8 @@ sctp_disposition_t sctp_sf_do_9_1_prm_abort( * TCB. This is a departure from our typical NOMEM handling. */ + sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, + SCTP_ERROR(ECONNABORTED)); /* Delete the established association. */ sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, SCTP_U32(SCTP_ERROR_USER_ABORT)); @@ -4175,6 +4180,8 @@ sctp_disposition_t sctp_sf_cookie_wait_prm_abort( * TCB. This is a departure from our typical NOMEM handling. */ + sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, + SCTP_ERROR(ECONNREFUSED)); /* Delete the established association. */ sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED, SCTP_U32(SCTP_ERROR_USER_ABORT)); @@ -4543,6 +4550,8 @@ sctp_disposition_t sctp_sf_do_6_3_3_rtx(const struct sctp_endpoint *ep, struct sctp_transport *transport = arg; if (asoc->overall_error_count >= asoc->max_retrans) { + sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, + SCTP_ERROR(ETIMEDOUT)); /* CMD_ASSOC_FAILED calls CMD_DELETE_TCB. */ sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, SCTP_U32(SCTP_ERROR_NO_ERROR)); @@ -4662,6 +4671,8 @@ sctp_disposition_t sctp_sf_t1_init_timer_expire(const struct sctp_endpoint *ep, SCTP_DEBUG_PRINTK("Giving up on INIT, attempts: %d" " max_init_attempts: %d\n", attempts, asoc->max_init_attempts); + sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, + SCTP_ERROR(ETIMEDOUT)); sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED, SCTP_U32(SCTP_ERROR_NO_ERROR)); return SCTP_DISPOSITION_DELETE_TCB; @@ -4711,6 +4722,8 @@ sctp_disposition_t sctp_sf_t1_cookie_timer_expire(const struct sctp_endpoint *ep sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); } else { + sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, + SCTP_ERROR(ETIMEDOUT)); sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED, SCTP_U32(SCTP_ERROR_NO_ERROR)); return SCTP_DISPOSITION_DELETE_TCB; @@ -4742,6 +4755,8 @@ sctp_disposition_t sctp_sf_t2_timer_expire(const struct sctp_endpoint *ep, SCTP_DEBUG_PRINTK("Timer T2 expired.\n"); if (asoc->overall_error_count >= asoc->max_retrans) { + sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, + SCTP_ERROR(ETIMEDOUT)); /* Note: CMD_ASSOC_FAILED calls CMD_DELETE_TCB. */ sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, SCTP_U32(SCTP_ERROR_NO_ERROR)); @@ -4817,6 +4832,8 @@ sctp_disposition_t sctp_sf_t4_timer_expire( if (asoc->overall_error_count >= asoc->max_retrans) { sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO)); + sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, + SCTP_ERROR(ETIMEDOUT)); sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, SCTP_U32(SCTP_ERROR_NO_ERROR)); SCTP_INC_STATS(SCTP_MIB_ABORTEDS); @@ -4870,6 +4887,8 @@ sctp_disposition_t sctp_sf_t5_timer_expire(const struct sctp_endpoint *ep, goto nomem; sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); + sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, + SCTP_ERROR(ETIMEDOUT)); sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, SCTP_U32(SCTP_ERROR_NO_ERROR)); @@ -5309,6 +5328,8 @@ static int sctp_eat_data(const struct sctp_association *asoc, * processing the rest of the chunks in the packet. */ sctp_add_cmd_sf(commands, SCTP_CMD_DISCARD_PACKET,SCTP_NULL()); + sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, + SCTP_ERROR(ECONNABORTED)); sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, SCTP_U32(SCTP_ERROR_NO_DATA)); SCTP_INC_STATS(SCTP_MIB_ABORTEDS); diff --git a/net/sctp/socket.c b/net/sctp/socket.c index b6e4b89539b3..90863307bcd9 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -1057,6 +1057,7 @@ static int __sctp_connect(struct sock* sk, inet_sk(sk)->dport = htons(asoc->peer.port); af = sctp_get_af_specific(to.sa.sa_family); af->to_sk_daddr(&to, sk); + sk->sk_err = 0; timeo = sock_sndtimeo(sk, sk->sk_socket->file->f_flags & O_NONBLOCK); err = sctp_wait_for_connect(asoc, &timeo); From 61c9fed41638249f8b6ca5345064eb1beb50179f Mon Sep 17 00:00:00 2001 From: Vladislav Yasevich Date: Fri, 19 May 2006 11:01:18 -0700 Subject: [PATCH 2/5] [SCTP]: A better solution to fix the race between sctp_peeloff() and sctp_rcv(). The goal is to hold the ref on the association/endpoint throughout the state-machine process. We accomplish like this: /* ref on the assoc/ep is taken during lookup */ if owned_by_user(sk) sctp_add_backlog(skb, sk); else inqueue_push(skb, sk); /* drop the ref on the assoc/ep */ However, in sctp_add_backlog() we take the ref on assoc/ep and hold it while the skb is on the backlog queue. This allows us to get rid of the sock_hold/sock_put in the lookup routines. Now sctp_backlog_rcv() needs to account for potential association move. In the unlikely event that association moved, we need to retest if the new socket is locked by user. If we don't this, we may have two packets racing up the stack toward the same socket and we can't deal with it. If the new socket is still locked, we'll just add the skb to its backlog continuing to hold the ref on the association. This get's rid of the need to move packets from one backlog to another and it also safe in case new packets arrive on the same backlog queue. The last step, is to lock the new socket when we are moving the association to it. This is needed in case any new packets arrive on the association when it moved. We want these to go to the backlog since we would like to avoid the race between this new packet and a packet that may be sitting on the backlog queue of the old socket toward the same association. Signed-off-by: Vladislav Yasevich Signed-off-by: Sridhar Samudrala --- net/sctp/input.c | 134 ++++++++++++++++++++++++++-------------------- net/sctp/socket.c | 16 +++--- 2 files changed, 86 insertions(+), 64 deletions(-) diff --git a/net/sctp/input.c b/net/sctp/input.c index 7523f4df2da6..1662f9cc869e 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) @@ -186,7 +188,6 @@ 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; @@ -197,7 +198,6 @@ 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; } @@ -253,25 +253,18 @@ 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)) - sk_add_backlog(sk, skb); + sctp_add_backlog(sk, skb); else - sctp_backlog_rcv(sk, skb); + sctp_inq_push(&chunk->rcvr->inqueue, chunk); - /* 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); + + /* Release the asoc/ep ref we took in the lookup calls. */ + if (asoc) + sctp_association_put(asoc); + else + sctp_endpoint_put(ep); return 0; @@ -280,8 +273,7 @@ discard_it: 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 @@ -290,56 +282,87 @@ 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 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 (rcvr->dead) { - sctp_chunk_free(chunk); - } else { - inqueue = &chunk->rcvr->inqueue; - sctp_inq_push(inqueue, chunk); - } + 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(); - /* 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)); - 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; + /* 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(); - 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; - } + sk_add_backlog(sk, skb); } /* Handle icmp frag needed error. */ @@ -453,7 +476,6 @@ 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; @@ -463,7 +485,6 @@ 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); } @@ -716,7 +737,6 @@ 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; } @@ -818,7 +838,6 @@ static struct sctp_association *__sctp_lookup_association( hit: *pt = transport; sctp_association_hold(asoc); - sock_hold(epb->sk); read_unlock(&head->lock); return asoc; } @@ -846,7 +865,6 @@ 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; } diff --git a/net/sctp/socket.c b/net/sctp/socket.c index 90863307bcd9..b1a17758003a 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -1229,7 +1229,7 @@ SCTP_STATIC void sctp_close(struct sock *sk, long timeout) ep = sctp_sk(sk)->ep; - /* Walk all associations on a socket, not on an endpoint. */ + /* Walk all associations on an endpoint. */ list_for_each_safe(pos, temp, &ep->asocs) { asoc = list_entry(pos, struct sctp_association, asocs); @@ -5318,6 +5318,7 @@ static int sctp_wait_for_sndbuf(struct sctp_association *asoc, long *timeo_p, */ sctp_release_sock(sk); current_timeo = schedule_timeout(current_timeo); + BUG_ON(sk != asoc->base.sk); sctp_lock_sock(sk); *timeo_p = current_timeo; @@ -5605,12 +5606,14 @@ static void sctp_sock_migrate(struct sock *oldsk, struct sock *newsk, */ newsp->type = type; - spin_lock_bh(&oldsk->sk_lock.slock); - /* Migrate the backlog from oldsk to newsk. */ - sctp_backlog_migrate(assoc, oldsk, newsk); - /* Migrate the association to the new socket. */ + /* Mark the new socket "in-use" by the user so that any packets + * that may arrive on the association after we've moved it are + * queued to the backlog. This prevents a potential race between + * backlog processing on the old socket and new-packet processing + * on the new socket. + */ + sctp_lock_sock(newsk); sctp_assoc_migrate(assoc, newsk); - spin_unlock_bh(&oldsk->sk_lock.slock); /* If the association on the newsk is already closed before accept() * is called, set RCV_SHUTDOWN flag. @@ -5619,6 +5622,7 @@ static void sctp_sock_migrate(struct sock *oldsk, struct sock *newsk, newsk->sk_shutdown |= RCV_SHUTDOWN; newsk->sk_state = SCTP_SS_ESTABLISHED; + sctp_release_sock(newsk); } /* This proto struct describes the ULP interface for SCTP. */ From dd2d1c6f2958d027e4591ca5d2a04dfe36ca6512 Mon Sep 17 00:00:00 2001 From: Vladislav Yasevich Date: Fri, 19 May 2006 11:52:20 -0700 Subject: [PATCH 3/5] [SCTP]: Respect the real chunk length when walking parameters. When performing bound checks during the parameter processing, we want to use the real chunk and paramter lengths for bounds instead of the rounded ones. This prevents us from potentially walking of the end if the chunk length was miscalculated. We still use rounded lengths when advancing the pointer. This was found during a conformance test that changed the chunk length without modifying parameters. Signed-off-by: Vlad Yasevich Signed-off-by: Sridhar Samudrala --- include/net/sctp/sctp.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/include/net/sctp/sctp.h b/include/net/sctp/sctp.h index e673b2c984e9..aa6033ca7cd8 100644 --- a/include/net/sctp/sctp.h +++ b/include/net/sctp/sctp.h @@ -461,12 +461,12 @@ static inline int sctp_frag_point(const struct sctp_sock *sp, int pmtu) * there is room for a param header too. */ #define sctp_walk_params(pos, chunk, member)\ -_sctp_walk_params((pos), (chunk), WORD_ROUND(ntohs((chunk)->chunk_hdr.length)), member) +_sctp_walk_params((pos), (chunk), ntohs((chunk)->chunk_hdr.length), member) #define _sctp_walk_params(pos, chunk, end, member)\ for (pos.v = chunk->member;\ pos.v <= (void *)chunk + end - sizeof(sctp_paramhdr_t) &&\ - pos.v <= (void *)chunk + end - WORD_ROUND(ntohs(pos.p->length)) &&\ + pos.v <= (void *)chunk + end - ntohs(pos.p->length) &&\ ntohs(pos.p->length) >= sizeof(sctp_paramhdr_t);\ pos.v += WORD_ROUND(ntohs(pos.p->length))) @@ -477,7 +477,7 @@ _sctp_walk_errors((err), (chunk_hdr), ntohs((chunk_hdr)->length)) for (err = (sctp_errhdr_t *)((void *)chunk_hdr + \ sizeof(sctp_chunkhdr_t));\ (void *)err <= (void *)chunk_hdr + end - sizeof(sctp_errhdr_t) &&\ - (void *)err <= (void *)chunk_hdr + end - WORD_ROUND(ntohs(err->length)) &&\ + (void *)err <= (void *)chunk_hdr + end - ntohs(err->length) &&\ ntohs(err->length) >= sizeof(sctp_errhdr_t); \ err = (sctp_errhdr_t *)((void *)err + WORD_ROUND(ntohs(err->length)))) From a601266e4f3c479790f373c2e3122a766d123652 Mon Sep 17 00:00:00 2001 From: Vladislav Yasevich Date: Fri, 19 May 2006 14:25:53 -0700 Subject: [PATCH 4/5] [SCTP]: Validate the parameter length in HB-ACK chunk. If SCTP receives a badly formatted HB-ACK chunk, it is possible that we may access invalid memory and potentially have a buffer overflow. We should really make sure that the chunk format is what we expect, before attempting to touch the data. Signed-off-by: Vlad Yasevich Signed-off-by: Sridhar Samudrala --- net/sctp/sm_statefuns.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c index 174f7a7c6cd1..8bc279219a72 100644 --- a/net/sctp/sm_statefuns.c +++ b/net/sctp/sm_statefuns.c @@ -1019,6 +1019,12 @@ sctp_disposition_t sctp_sf_backbeat_8_3(const struct sctp_endpoint *ep, commands); hbinfo = (sctp_sender_hb_info_t *) chunk->skb->data; + /* Make sure that the length of the parameter is what we expect */ + if (ntohs(hbinfo->param_hdr.length) != + sizeof(sctp_sender_hb_info_t)) { + return SCTP_DISPOSITION_DISCARD; + } + from_addr = hbinfo->daddr; link = sctp_assoc_lookup_paddr(asoc, &from_addr); From b89498a1c2941c00889dd025f52dcb653a5083bc Mon Sep 17 00:00:00 2001 From: Vladislav Yasevich Date: Fri, 19 May 2006 14:32:06 -0700 Subject: [PATCH 5/5] [SCTP]: Allow linger to abort 1-N style sockets. Enable SO_LINGER functionality for 1-N style sockets. The socket API draft will be clarfied to allow for this functionality. The linger settings will apply to all associations on a given socket. Signed-off-by: Vladislav Yasevich Signed-off-by: Sridhar Samudrala --- net/sctp/socket.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/net/sctp/socket.c b/net/sctp/socket.c index b1a17758003a..174d4d35e951 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -1242,13 +1242,13 @@ SCTP_STATIC void sctp_close(struct sock *sk, long timeout) if (sctp_state(asoc, CLOSED)) { sctp_unhash_established(asoc); sctp_association_free(asoc); + continue; + } + } - } else if (sock_flag(sk, SOCK_LINGER) && - !sk->sk_lingertime) - sctp_primitive_ABORT(asoc, NULL); - else - sctp_primitive_SHUTDOWN(asoc, NULL); - } else + if (sock_flag(sk, SOCK_LINGER) && !sk->sk_lingertime) + sctp_primitive_ABORT(asoc, NULL); + else sctp_primitive_SHUTDOWN(asoc, NULL); }