SCTP: Update RCU handling during the ADD-IP case

After learning more about rcu, it looks like the ADD-IP hadling
doesn't need to call call_rcu_bh.  All the rcu critical sections
use rcu_read_lock, so using call_rcu_bh is wrong here.
Now, restore the local_bh_disable() code blocks and use normal
call_rcu() calls.  Also restore the missing return statement.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>

4 files changed, 10 insertions, 15 deletions

diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h
index 482c2aab3d67..a17701740624 100644
--- a/include/net/sctp/structs.h
+++ b/include/net/sctp/structs.h
@@ -1185,9 +1185,7 @@ int sctp_bind_addr_copy(struct sctp_bind_addr *dest,
                         int flags);
 int sctp_add_bind_addr(struct sctp_bind_addr *, union sctp_addr *,
                        __u8 use_as_src, gfp_t gfp);
-int sctp_del_bind_addr(struct sctp_bind_addr *, union sctp_addr *,
-                        void fastcall (*rcu_call)(struct rcu_head *,
-                                          void (*func)(struct rcu_head *)));
+int sctp_del_bind_addr(struct sctp_bind_addr *, union sctp_addr *);
 int sctp_bind_addr_match(struct sctp_bind_addr *, const union sctp_addr *,
                          struct sctp_sock *);
 union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr   *bp,
diff --git a/net/sctp/bind_addr.c b/net/sctp/bind_addr.c
index dfffa94fb9f6..cae95af9a8cc 100644
--- a/net/sctp/bind_addr.c
+++ b/net/sctp/bind_addr.c
@@ -180,9 +180,7 @@ 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,
-                        void fastcall (*rcu_call)(struct rcu_head *head,
-                                         void (*func)(struct rcu_head *head)))
+int sctp_del_bind_addr(struct sctp_bind_addr *bp, union sctp_addr *del_addr)
 {
         struct sctp_sockaddr_entry *addr, *temp;
 
@@ -198,15 +196,10 @@ int sctp_del_bind_addr(struct sctp_bind_addr *bp, union sctp_addr *del_addr,
                 }
         }
 
-        /* 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);
+                call_rcu(&addr->rcu, sctp_local_addr_free);
                 SCTP_DBG_OBJCNT_DEC(addr);
+                return 0;
         }
 
         return -EINVAL;
diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c
index 5de4729fe993..c60564dd169d 100644
--- a/net/sctp/sm_make_chunk.c
+++ b/net/sctp/sm_make_chunk.c
@@ -2953,13 +2953,17 @@ static int sctp_asconf_param_success(struct sctp_association *asoc,
                 /* This is always done in BH context with a socket lock
                  * held, so the list can not change.
                  */
+                local_bh_disable();
                 list_for_each_entry(saddr, &bp->address_list, list) {
                         if (sctp_cmp_addr_exact(&saddr->a, &addr))
                                 saddr->use_as_src = 1;
                 }
+                local_bh_enable();
                 break;
         case SCTP_PARAM_DEL_IP:
-                retval = sctp_del_bind_addr(bp, &addr, call_rcu_bh);
+                local_bh_disable();
+                retval = sctp_del_bind_addr(bp, &addr);
+                local_bh_enable();
                 list_for_each(pos, &asoc->peer.transport_addr_list) {
                         transport = list_entry(pos, struct sctp_transport,
                                                  transports);
diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index a7ecf3159e53..6ce9b490fad5 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -660,7 +660,7 @@ static int sctp_bindx_rem(struct sock *sk, struct sockaddr *addrs, int addrcnt)
                  * socket routing and failover schemes. Refer to comments in
                  * sctp_do_bind(). -daisy
                  */
-                retval = sctp_del_bind_addr(bp, sa_addr, call_rcu);
+                retval = sctp_del_bind_addr(bp, sa_addr);
 
                 addr_buf += af->sockaddr_len;
 err_bindx_rem: