[SCTP]: Handle address add/delete events in a more efficient way.
Currently in SCTP, we maintain a local address list by rebuilding the whole
list from the device list whenever we get a address add/delete event.
This patch fixes it by only adding/deleting the address for which we
receive the event.
Also removed the sctp_local_addr_lock() which is no longer needed as we
now use list_for_each_safe() to traverse this list. This fixes the bugs
in sctp_copy_laddrs_xxx() routines where we do copy_to_user() while
holding this lock.
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h
index c089f93..b00d85e 100644
--- a/include/net/sctp/structs.h
+++ b/include/net/sctp/structs.h
@@ -201,13 +201,12 @@
struct sctp_bind_hashbucket *port_hashtable;
/* This is the global local address list.
- * We actively maintain this complete list of interfaces on
- * the system by catching routing events.
+ * We actively maintain this complete list of addresses on
+ * the system by catching address add/delete events.
*
* It is a list of sctp_sockaddr_entry.
*/
struct list_head local_addr_list;
- spinlock_t local_addr_lock;
/* Flag to indicate if addip is enabled. */
int addip_enable;
@@ -243,7 +242,6 @@
#define sctp_port_alloc_lock (sctp_globals.port_alloc_lock)
#define sctp_port_hashtable (sctp_globals.port_hashtable)
#define sctp_local_addr_list (sctp_globals.local_addr_list)
-#define sctp_local_addr_lock (sctp_globals.local_addr_lock)
#define sctp_addip_enable (sctp_globals.addip_enable)
#define sctp_prsctp_enable (sctp_globals.prsctp_enable)
diff --git a/net/sctp/ipv6.c b/net/sctp/ipv6.c
index 3c3e560..d8d36de 100644
--- a/net/sctp/ipv6.c
+++ b/net/sctp/ipv6.c
@@ -78,8 +78,44 @@
#include <asm/uaccess.h>
+/* Event handler for inet6 address addition/deletion events. */
+int sctp_inet6addr_event(struct notifier_block *this, unsigned long ev,
+ void *ptr)
+{
+ struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr;
+ struct sctp_sockaddr_entry *addr;
+ struct list_head *pos, *temp;
+
+ switch (ev) {
+ case NETDEV_UP:
+ addr = kmalloc(sizeof(struct sctp_sockaddr_entry), GFP_ATOMIC);
+ if (addr) {
+ addr->a.v6.sin6_family = AF_INET6;
+ addr->a.v6.sin6_port = 0;
+ memcpy(&addr->a.v6.sin6_addr, &ifa->addr,
+ sizeof(struct in6_addr));
+ addr->a.v6.sin6_scope_id = ifa->idev->dev->ifindex;
+ list_add_tail(&addr->list, &sctp_local_addr_list);
+ }
+ break;
+ case NETDEV_DOWN:
+ list_for_each_safe(pos, temp, &sctp_local_addr_list) {
+ addr = list_entry(pos, struct sctp_sockaddr_entry, list);
+ if (ipv6_addr_equal(&addr->a.v6.sin6_addr, &ifa->addr)) {
+ list_del(pos);
+ kfree(addr);
+ break;
+ }
+ }
+
+ break;
+ }
+
+ return NOTIFY_DONE;
+}
+
static struct notifier_block sctp_inet6addr_notifier = {
- .notifier_call = sctp_inetaddr_event,
+ .notifier_call = sctp_inet6addr_event,
};
/* ICMP error handler. */
diff --git a/net/sctp/protocol.c b/net/sctp/protocol.c
index f2ba861..b61f334 100644
--- a/net/sctp/protocol.c
+++ b/net/sctp/protocol.c
@@ -163,7 +163,7 @@
/* Extract our IP addresses from the system and stash them in the
* protocol structure.
*/
-static void __sctp_get_local_addr_list(void)
+static void sctp_get_local_addr_list(void)
{
struct net_device *dev;
struct list_head *pos;
@@ -179,17 +179,8 @@
read_unlock(&dev_base_lock);
}
-static void sctp_get_local_addr_list(void)
-{
- unsigned long flags;
-
- sctp_spin_lock_irqsave(&sctp_local_addr_lock, flags);
- __sctp_get_local_addr_list();
- sctp_spin_unlock_irqrestore(&sctp_local_addr_lock, flags);
-}
-
/* Free the existing local addresses. */
-static void __sctp_free_local_addr_list(void)
+static void sctp_free_local_addr_list(void)
{
struct sctp_sockaddr_entry *addr;
struct list_head *pos, *temp;
@@ -201,27 +192,15 @@
}
}
-/* Free the existing local addresses. */
-static void sctp_free_local_addr_list(void)
-{
- unsigned long flags;
-
- sctp_spin_lock_irqsave(&sctp_local_addr_lock, flags);
- __sctp_free_local_addr_list();
- sctp_spin_unlock_irqrestore(&sctp_local_addr_lock, flags);
-}
-
/* 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;
- unsigned long flags;
+ struct list_head *pos, *temp;
- sctp_spin_lock_irqsave(&sctp_local_addr_lock, flags);
- list_for_each(pos, &sctp_local_addr_list) {
+ list_for_each_safe(pos, temp, &sctp_local_addr_list) {
addr = list_entry(pos, struct sctp_sockaddr_entry, list);
if (sctp_in_scope(&addr->a, scope)) {
/* Now that the address is in scope, check to see if
@@ -242,7 +221,6 @@
}
end_copy:
- sctp_spin_unlock_irqrestore(&sctp_local_addr_lock, flags);
return error;
}
@@ -622,18 +600,36 @@
seq_printf(seq, "%d.%d.%d.%d ", NIPQUAD(addr->v4.sin_addr));
}
-/* Event handler for inet address addition/deletion events.
- * Basically, whenever there is an event, we re-build our local address list.
- */
+/* Event handler for inet address addition/deletion events. */
int sctp_inetaddr_event(struct notifier_block *this, unsigned long ev,
void *ptr)
{
- unsigned long flags;
+ struct in_ifaddr *ifa = (struct in_ifaddr *)ptr;
+ struct sctp_sockaddr_entry *addr;
+ struct list_head *pos, *temp;
- sctp_spin_lock_irqsave(&sctp_local_addr_lock, flags);
- __sctp_free_local_addr_list();
- __sctp_get_local_addr_list();
- sctp_spin_unlock_irqrestore(&sctp_local_addr_lock, flags);
+ switch (ev) {
+ case NETDEV_UP:
+ addr = kmalloc(sizeof(struct sctp_sockaddr_entry), GFP_ATOMIC);
+ if (addr) {
+ 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);
+ }
+ break;
+ case NETDEV_DOWN:
+ list_for_each_safe(pos, temp, &sctp_local_addr_list) {
+ addr = list_entry(pos, struct sctp_sockaddr_entry, list);
+ if (addr->a.v4.sin_addr.s_addr == ifa->ifa_local) {
+ list_del(pos);
+ kfree(addr);
+ break;
+ }
+ }
+
+ break;
+ }
return NOTIFY_DONE;
}
@@ -1172,13 +1168,12 @@
/* 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. */
register_inetaddr_notifier(&sctp_inetaddr_notifier);
- sctp_get_local_addr_list();
-
__unsafe(THIS_MODULE);
status = 0;
out:
diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 1e8132b..fa29eae 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -3821,10 +3821,9 @@
sctp_assoc_t id;
struct sctp_bind_addr *bp;
struct sctp_association *asoc;
- struct list_head *pos;
+ struct list_head *pos, *temp;
struct sctp_sockaddr_entry *addr;
rwlock_t *addr_lock;
- unsigned long flags;
int cnt = 0;
if (len != sizeof(sctp_assoc_t))
@@ -3859,8 +3858,7 @@
addr = list_entry(bp->address_list.next,
struct sctp_sockaddr_entry, list);
if (sctp_is_any(&addr->a)) {
- sctp_spin_lock_irqsave(&sctp_local_addr_lock, flags);
- list_for_each(pos, &sctp_local_addr_list) {
+ list_for_each_safe(pos, temp, &sctp_local_addr_list) {
addr = list_entry(pos,
struct sctp_sockaddr_entry,
list);
@@ -3869,8 +3867,6 @@
continue;
cnt++;
}
- sctp_spin_unlock_irqrestore(&sctp_local_addr_lock,
- flags);
} else {
cnt = 1;
}
@@ -3892,15 +3888,13 @@
static int sctp_copy_laddrs_to_user_old(struct sock *sk, __u16 port, int max_addrs,
void __user *to)
{
- struct list_head *pos;
+ struct list_head *pos, *next;
struct sctp_sockaddr_entry *addr;
- unsigned long flags;
union sctp_addr temp;
int cnt = 0;
int addrlen;
- sctp_spin_lock_irqsave(&sctp_local_addr_lock, flags);
- list_for_each(pos, &sctp_local_addr_list) {
+ list_for_each_safe(pos, next, &sctp_local_addr_list) {
addr = list_entry(pos, struct sctp_sockaddr_entry, list);
if ((PF_INET == sk->sk_family) &&
(AF_INET6 == addr->a.sa.sa_family))
@@ -3909,16 +3903,13 @@
sctp_get_pf_specific(sk->sk_family)->addr_v4map(sctp_sk(sk),
&temp);
addrlen = sctp_get_af_specific(temp.sa.sa_family)->sockaddr_len;
- if (copy_to_user(to, &temp, addrlen)) {
- sctp_spin_unlock_irqrestore(&sctp_local_addr_lock,
- flags);
+ if (copy_to_user(to, &temp, addrlen))
return -EFAULT;
- }
+
to += addrlen;
cnt ++;
if (cnt >= max_addrs) break;
}
- sctp_spin_unlock_irqrestore(&sctp_local_addr_lock, flags);
return cnt;
}
@@ -3926,15 +3917,13 @@
static int sctp_copy_laddrs_to_user(struct sock *sk, __u16 port,
void __user **to, size_t space_left)
{
- struct list_head *pos;
+ struct list_head *pos, *next;
struct sctp_sockaddr_entry *addr;
- unsigned long flags;
union sctp_addr temp;
int cnt = 0;
int addrlen;
- sctp_spin_lock_irqsave(&sctp_local_addr_lock, flags);
- list_for_each(pos, &sctp_local_addr_list) {
+ list_for_each_safe(pos, next, &sctp_local_addr_list) {
addr = list_entry(pos, struct sctp_sockaddr_entry, list);
if ((PF_INET == sk->sk_family) &&
(AF_INET6 == addr->a.sa.sa_family))
@@ -3945,16 +3934,13 @@
addrlen = sctp_get_af_specific(temp.sa.sa_family)->sockaddr_len;
if(space_left<addrlen)
return -ENOMEM;
- if (copy_to_user(*to, &temp, addrlen)) {
- sctp_spin_unlock_irqrestore(&sctp_local_addr_lock,
- flags);
+ if (copy_to_user(*to, &temp, addrlen))
return -EFAULT;
- }
+
*to += addrlen;
cnt ++;
space_left -= addrlen;
}
- sctp_spin_unlock_irqrestore(&sctp_local_addr_lock, flags);
return cnt;
}