diff options
Diffstat (limited to 'net/sctp/bind_addr.c')
-rw-r--r-- | net/sctp/bind_addr.c | 70 |
1 files changed, 47 insertions, 23 deletions
diff --git a/net/sctp/bind_addr.c b/net/sctp/bind_addr.c index fdb287a9e2e..dfffa94fb9f 100644 --- a/net/sctp/bind_addr.c +++ b/net/sctp/bind_addr.c @@ -163,9 +163,15 @@ int sctp_add_bind_addr(struct sctp_bind_addr *bp, union sctp_addr *new, addr->a.v4.sin_port = htons(bp->port); addr->use_as_src = use_as_src; + addr->valid = 1; INIT_LIST_HEAD(&addr->list); - list_add_tail(&addr->list, &bp->address_list); + INIT_RCU_HEAD(&addr->rcu); + + /* We always hold a socket lock when calling this function, + * and that acts as a writer synchronizing lock. + */ + list_add_tail_rcu(&addr->list, &bp->address_list); SCTP_DBG_OBJCNT_INC(addr); return 0; @@ -174,23 +180,35 @@ int sctp_add_bind_addr(struct sctp_bind_addr *bp, union sctp_addr *new, /* Delete an address from the bind address list in the SCTP_bind_addr * structure. */ -int sctp_del_bind_addr(struct sctp_bind_addr *bp, union sctp_addr *del_addr) +int sctp_del_bind_addr(struct sctp_bind_addr *bp, union sctp_addr *del_addr, + void fastcall (*rcu_call)(struct rcu_head *head, + void (*func)(struct rcu_head *head))) { - struct list_head *pos, *temp; - struct sctp_sockaddr_entry *addr; + struct sctp_sockaddr_entry *addr, *temp; - list_for_each_safe(pos, temp, &bp->address_list) { - addr = list_entry(pos, struct sctp_sockaddr_entry, list); + /* We hold the socket lock when calling this function, + * and that acts as a writer synchronizing lock. + */ + list_for_each_entry_safe(addr, temp, &bp->address_list, list) { if (sctp_cmp_addr_exact(&addr->a, del_addr)) { /* Found the exact match. */ - list_del(pos); - kfree(addr); - SCTP_DBG_OBJCNT_DEC(addr); - - return 0; + addr->valid = 0; + list_del_rcu(&addr->list); + break; } } + /* Call the rcu callback provided in the args. This function is + * called by both BH packet processing and user side socket option + * processing, but it works on different lists in those 2 contexts. + * Each context provides it's own callback, whether call_rcu_bh() + * or call_rcu(), to make sure that we wait for an appropriate time. + */ + if (addr && !addr->valid) { + rcu_call(&addr->rcu, sctp_local_addr_free); + SCTP_DBG_OBJCNT_DEC(addr); + } + return -EINVAL; } @@ -300,15 +318,20 @@ int sctp_bind_addr_match(struct sctp_bind_addr *bp, struct sctp_sock *opt) { struct sctp_sockaddr_entry *laddr; - struct list_head *pos; - - list_for_each(pos, &bp->address_list) { - laddr = list_entry(pos, struct sctp_sockaddr_entry, list); - if (opt->pf->cmp_addr(&laddr->a, addr, opt)) - return 1; + int match = 0; + + rcu_read_lock(); + list_for_each_entry_rcu(laddr, &bp->address_list, list) { + if (!laddr->valid) + continue; + if (opt->pf->cmp_addr(&laddr->a, addr, opt)) { + match = 1; + break; + } } + rcu_read_unlock(); - return 0; + return match; } /* Find the first address in the bind address list that is not present in @@ -323,18 +346,19 @@ union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr *bp, union sctp_addr *addr; void *addr_buf; struct sctp_af *af; - struct list_head *pos; int i; - list_for_each(pos, &bp->address_list) { - laddr = list_entry(pos, struct sctp_sockaddr_entry, list); - + /* This is only called sctp_send_asconf_del_ip() and we hold + * the socket lock in that code patch, so that address list + * can't change. + */ + list_for_each_entry(laddr, &bp->address_list, list) { addr_buf = (union sctp_addr *)addrs; for (i = 0; i < addrcnt; i++) { addr = (union sctp_addr *)addr_buf; af = sctp_get_af_specific(addr->v4.sin_family); if (!af) - return NULL; + break; if (opt->pf->cmp_addr(&laddr->a, addr, opt)) break; |