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Diffstat (limited to 'net/sctp/protocol.c')
-rw-r--r--net/sctp/protocol.c79
1 files changed, 49 insertions, 30 deletions
diff --git a/net/sctp/protocol.c b/net/sctp/protocol.c
index e98579b788b..3d036cdfae4 100644
--- a/net/sctp/protocol.c
+++ b/net/sctp/protocol.c
@@ -153,6 +153,9 @@ static void sctp_v4_copy_addrlist(struct list_head *addrlist,
addr->a.v4.sin_family = AF_INET;
addr->a.v4.sin_port = 0;
addr->a.v4.sin_addr.s_addr = ifa->ifa_local;
+ addr->valid = 1;
+ INIT_LIST_HEAD(&addr->list);
+ INIT_RCU_HEAD(&addr->rcu);
list_add_tail(&addr->list, addrlist);
}
}
@@ -192,16 +195,24 @@ static void sctp_free_local_addr_list(void)
}
}
+void sctp_local_addr_free(struct rcu_head *head)
+{
+ struct sctp_sockaddr_entry *e = container_of(head,
+ struct sctp_sockaddr_entry, rcu);
+ kfree(e);
+}
+
/* Copy the local addresses which are valid for 'scope' into 'bp'. */
int sctp_copy_local_addr_list(struct sctp_bind_addr *bp, sctp_scope_t scope,
gfp_t gfp, int copy_flags)
{
struct sctp_sockaddr_entry *addr;
int error = 0;
- struct list_head *pos, *temp;
- list_for_each_safe(pos, temp, &sctp_local_addr_list) {
- addr = list_entry(pos, struct sctp_sockaddr_entry, list);
+ rcu_read_lock();
+ list_for_each_entry_rcu(addr, &sctp_local_addr_list, list) {
+ if (!addr->valid)
+ continue;
if (sctp_in_scope(&addr->a, scope)) {
/* Now that the address is in scope, check to see if
* the address type is really supported by the local
@@ -213,7 +224,7 @@ int sctp_copy_local_addr_list(struct sctp_bind_addr *bp, sctp_scope_t scope,
(copy_flags & SCTP_ADDR6_ALLOWED) &&
(copy_flags & SCTP_ADDR6_PEERSUPP)))) {
error = sctp_add_bind_addr(bp, &addr->a, 1,
- GFP_ATOMIC);
+ GFP_ATOMIC);
if (error)
goto end_copy;
}
@@ -221,6 +232,7 @@ int sctp_copy_local_addr_list(struct sctp_bind_addr *bp, sctp_scope_t scope,
}
end_copy:
+ rcu_read_unlock();
return error;
}
@@ -416,9 +428,7 @@ static struct dst_entry *sctp_v4_get_dst(struct sctp_association *asoc,
struct rtable *rt;
struct flowi fl;
struct sctp_bind_addr *bp;
- rwlock_t *addr_lock;
struct sctp_sockaddr_entry *laddr;
- struct list_head *pos;
struct dst_entry *dst = NULL;
union sctp_addr dst_saddr;
@@ -447,23 +457,20 @@ static struct dst_entry *sctp_v4_get_dst(struct sctp_association *asoc,
goto out;
bp = &asoc->base.bind_addr;
- addr_lock = &asoc->base.addr_lock;
if (dst) {
/* Walk through the bind address list and look for a bind
* address that matches the source address of the returned dst.
*/
- sctp_read_lock(addr_lock);
- list_for_each(pos, &bp->address_list) {
- laddr = list_entry(pos, struct sctp_sockaddr_entry,
- list);
- if (!laddr->use_as_src)
+ rcu_read_lock();
+ list_for_each_entry_rcu(laddr, &bp->address_list, list) {
+ if (!laddr->valid || !laddr->use_as_src)
continue;
sctp_v4_dst_saddr(&dst_saddr, dst, htons(bp->port));
if (sctp_v4_cmp_addr(&dst_saddr, &laddr->a))
goto out_unlock;
}
- sctp_read_unlock(addr_lock);
+ rcu_read_unlock();
/* None of the bound addresses match the source address of the
* dst. So release it.
@@ -475,10 +482,10 @@ static struct dst_entry *sctp_v4_get_dst(struct sctp_association *asoc,
/* Walk through the bind address list and try to get a dst that
* matches a bind address as the source address.
*/
- sctp_read_lock(addr_lock);
- list_for_each(pos, &bp->address_list) {
- laddr = list_entry(pos, struct sctp_sockaddr_entry, list);
-
+ rcu_read_lock();
+ list_for_each_entry_rcu(laddr, &bp->address_list, list) {
+ if (!laddr->valid)
+ continue;
if ((laddr->use_as_src) &&
(AF_INET == laddr->a.sa.sa_family)) {
fl.fl4_src = laddr->a.v4.sin_addr.s_addr;
@@ -490,7 +497,7 @@ static struct dst_entry *sctp_v4_get_dst(struct sctp_association *asoc,
}
out_unlock:
- sctp_read_unlock(addr_lock);
+ rcu_read_unlock();
out:
if (dst)
SCTP_DEBUG_PRINTK("rt_dst:%u.%u.%u.%u, rt_src:%u.%u.%u.%u\n",
@@ -600,13 +607,18 @@ static void sctp_v4_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
seq_printf(seq, "%d.%d.%d.%d ", NIPQUAD(addr->v4.sin_addr));
}
-/* Event handler for inet address addition/deletion events. */
+/* Event handler for inet address addition/deletion events.
+ * The sctp_local_addr_list needs to be protocted by a spin lock since
+ * multiple notifiers (say IPv4 and IPv6) may be running at the same
+ * time and thus corrupt the list.
+ * The reader side is protected with RCU.
+ */
static int sctp_inetaddr_event(struct notifier_block *this, unsigned long ev,
void *ptr)
{
struct in_ifaddr *ifa = (struct in_ifaddr *)ptr;
- struct sctp_sockaddr_entry *addr;
- struct list_head *pos, *temp;
+ struct sctp_sockaddr_entry *addr = NULL;
+ struct sctp_sockaddr_entry *temp;
switch (ev) {
case NETDEV_UP:
@@ -615,19 +627,25 @@ static int sctp_inetaddr_event(struct notifier_block *this, unsigned long ev,
addr->a.v4.sin_family = AF_INET;
addr->a.v4.sin_port = 0;
addr->a.v4.sin_addr.s_addr = ifa->ifa_local;
- list_add_tail(&addr->list, &sctp_local_addr_list);
+ addr->valid = 1;
+ spin_lock_bh(&sctp_local_addr_lock);
+ list_add_tail_rcu(&addr->list, &sctp_local_addr_list);
+ spin_unlock_bh(&sctp_local_addr_lock);
}
break;
case NETDEV_DOWN:
- list_for_each_safe(pos, temp, &sctp_local_addr_list) {
- addr = list_entry(pos, struct sctp_sockaddr_entry, list);
+ spin_lock_bh(&sctp_local_addr_lock);
+ list_for_each_entry_safe(addr, temp,
+ &sctp_local_addr_list, list) {
if (addr->a.v4.sin_addr.s_addr == ifa->ifa_local) {
- list_del(pos);
- kfree(addr);
+ addr->valid = 0;
+ list_del_rcu(&addr->list);
break;
}
}
-
+ spin_unlock_bh(&sctp_local_addr_lock);
+ if (addr && !addr->valid)
+ call_rcu(&addr->rcu, sctp_local_addr_free);
break;
}
@@ -1160,6 +1178,7 @@ SCTP_STATIC __init int sctp_init(void)
/* Initialize the local address list. */
INIT_LIST_HEAD(&sctp_local_addr_list);
+ spin_lock_init(&sctp_local_addr_lock);
sctp_get_local_addr_list();
/* Register notifier for inet address additions/deletions. */
@@ -1227,6 +1246,9 @@ SCTP_STATIC __exit void sctp_exit(void)
sctp_v6_del_protocol();
inet_del_protocol(&sctp_protocol, IPPROTO_SCTP);
+ /* Unregister notifier for inet address additions/deletions. */
+ unregister_inetaddr_notifier(&sctp_inetaddr_notifier);
+
/* Free the local address list. */
sctp_free_local_addr_list();
@@ -1240,9 +1262,6 @@ SCTP_STATIC __exit void sctp_exit(void)
inet_unregister_protosw(&sctp_stream_protosw);
inet_unregister_protosw(&sctp_seqpacket_protosw);
- /* Unregister notifier for inet address additions/deletions. */
- unregister_inetaddr_notifier(&sctp_inetaddr_notifier);
-
sctp_sysctl_unregister();
list_del(&sctp_ipv4_specific.list);
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-12-28 12:24:51 +0000