[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>

1 files changed, 2 insertions, 4 deletions

diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h
index c089f93ba591..b00d85e14fe1 100644
--- a/include/net/sctp/structs.h
+++ b/include/net/sctp/structs.h
@@ -201,13 +201,12 @@ extern struct sctp_globals {
         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 @@ extern struct sctp_globals {
 #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)