1 files changed, 52 insertions, 82 deletions

diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 33354602ae86..772fbfb4bfda 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -367,14 +367,10 @@ SCTP_STATIC int sctp_do_bind(struct sock *sk, union sctp_addr *addr, int len)
         if (!bp->port)
                 bp->port = inet_sk(sk)->num;
 
-        /* Add the address to the bind address list.  */
-        sctp_local_bh_disable();
-        sctp_write_lock(&ep->base.addr_lock);
-
-        /* Use GFP_ATOMIC since BHs are disabled.  */
+        /* Add the address to the bind address list.
+         * Use GFP_ATOMIC since BHs will be disabled.
+         */
         ret = sctp_add_bind_addr(bp, addr, 1, GFP_ATOMIC);
-        sctp_write_unlock(&ep->base.addr_lock);
-        sctp_local_bh_enable();
 
         /* Copy back into socket for getsockname() use. */
         if (!ret) {
@@ -544,15 +540,12 @@ static int sctp_send_asconf_add_ip(struct sock		*sk,
                 if (i < addrcnt)
                         continue;
 
-                /* Use the first address in bind addr list of association as
-                 * Address Parameter of ASCONF CHUNK.
+                /* Use the first valid address in bind addr list of
+                 * association as Address Parameter of ASCONF CHUNK.
                  */
-                sctp_read_lock(&asoc->base.addr_lock);
                 bp = &asoc->base.bind_addr;
                 p = bp->address_list.next;
                 laddr = list_entry(p, struct sctp_sockaddr_entry, list);
-                sctp_read_unlock(&asoc->base.addr_lock);
-
                 chunk = sctp_make_asconf_update_ip(asoc, &laddr->a, addrs,
                                                    addrcnt, SCTP_PARAM_ADD_IP);
                 if (!chunk) {
@@ -567,8 +560,6 @@ static int sctp_send_asconf_add_ip(struct sock		*sk,
                 /* Add the new addresses to the bind address list with
                  * use_as_src set to 0.
                  */
-                sctp_local_bh_disable();
-                sctp_write_lock(&asoc->base.addr_lock);
                 addr_buf = addrs;
                 for (i = 0; i < addrcnt; i++) {
                         addr = (union sctp_addr *)addr_buf;
@@ -578,8 +569,6 @@ static int sctp_send_asconf_add_ip(struct sock		*sk,
                                                     GFP_ATOMIC);
                         addr_buf += af->sockaddr_len;
                 }
-                sctp_write_unlock(&asoc->base.addr_lock);
-                sctp_local_bh_enable();
         }
 
 out:
@@ -651,13 +640,7 @@ 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
                  */
-                sctp_local_bh_disable();
-                sctp_write_lock(&ep->base.addr_lock);
-
-                retval = sctp_del_bind_addr(bp, sa_addr);
-
-                sctp_write_unlock(&ep->base.addr_lock);
-                sctp_local_bh_enable();
+                retval = sctp_del_bind_addr(bp, sa_addr, call_rcu);
 
                 addr_buf += af->sockaddr_len;
 err_bindx_rem:
@@ -748,14 +731,16 @@ static int sctp_send_asconf_del_ip(struct sock		*sk,
                  * make sure that we do not delete all the addresses in the
                  * association.
                  */
-                sctp_read_lock(&asoc->base.addr_lock);
                 bp = &asoc->base.bind_addr;
                 laddr = sctp_find_unmatch_addr(bp, (union sctp_addr *)addrs,
                                                addrcnt, sp);
-                sctp_read_unlock(&asoc->base.addr_lock);
                 if (!laddr)
                         continue;
 
+                /* We do not need RCU protection throughout this loop
+                 * because this is done under a socket lock from the
+                 * setsockopt call.
+                 */
                 chunk = sctp_make_asconf_update_ip(asoc, laddr, addrs, addrcnt,
                                                    SCTP_PARAM_DEL_IP);
                 if (!chunk) {
@@ -766,23 +751,16 @@ static int sctp_send_asconf_del_ip(struct sock		*sk,
                 /* Reset use_as_src flag for the addresses in the bind address
                  * list that are to be deleted.
                  */
-                sctp_local_bh_disable();
-                sctp_write_lock(&asoc->base.addr_lock);
                 addr_buf = addrs;
                 for (i = 0; i < addrcnt; i++) {
                         laddr = (union sctp_addr *)addr_buf;
                         af = sctp_get_af_specific(laddr->v4.sin_family);
-                        list_for_each(pos1, &bp->address_list) {
-                                saddr = list_entry(pos1,
-                                                   struct sctp_sockaddr_entry,
-                                                   list);
+                        list_for_each_entry(saddr, &bp->address_list, list) {
                                 if (sctp_cmp_addr_exact(&saddr->a, laddr))
                                         saddr->use_as_src = 0;
                         }
                         addr_buf += af->sockaddr_len;
                 }
-                sctp_write_unlock(&asoc->base.addr_lock);
-                sctp_local_bh_enable();
 
                 /* Update the route and saddr entries for all the transports
                  * as some of the addresses in the bind address list are
@@ -4059,9 +4037,7 @@ static int sctp_getsockopt_local_addrs_num_old(struct sock *sk, int len,
         sctp_assoc_t id;
         struct sctp_bind_addr *bp;
         struct sctp_association *asoc;
-        struct list_head *pos, *temp;
         struct sctp_sockaddr_entry *addr;
-        rwlock_t *addr_lock;
         int cnt = 0;
 
         if (len < sizeof(sctp_assoc_t))
@@ -4078,17 +4054,13 @@ static int sctp_getsockopt_local_addrs_num_old(struct sock *sk, int len,
          */
         if (0 == id) {
                 bp = &sctp_sk(sk)->ep->base.bind_addr;
-                addr_lock = &sctp_sk(sk)->ep->base.addr_lock;
         } else {
                 asoc = sctp_id2assoc(sk, id);
                 if (!asoc)
                         return -EINVAL;
                 bp = &asoc->base.bind_addr;
-                addr_lock = &asoc->base.addr_lock;
         }
 
-        sctp_read_lock(addr_lock);
-
         /* If the endpoint is bound to 0.0.0.0 or ::0, count the valid
          * addresses from the global local address list.
          */
@@ -4096,27 +4068,33 @@ static int sctp_getsockopt_local_addrs_num_old(struct sock *sk, int len,
                 addr = list_entry(bp->address_list.next,
                                   struct sctp_sockaddr_entry, list);
                 if (sctp_is_any(&addr->a)) {
-                        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 ((PF_INET == sk->sk_family) &&
                                     (AF_INET6 == addr->a.sa.sa_family))
                                         continue;
+
                                 cnt++;
                         }
+                        rcu_read_unlock();
                 } else {
                         cnt = 1;
                 }
                 goto done;
         }
 
-        list_for_each(pos, &bp->address_list) {
+        /* Protection on the bound address list is not needed,
+         * since in the socket option context we hold the socket lock,
+         * so there is no way that the bound address list can change.
+         */
+        list_for_each_entry(addr, &bp->address_list, list) {
                 cnt ++;
         }
-
 done:
-        sctp_read_unlock(addr_lock);
         return cnt;
 }
 
@@ -4127,14 +4105,16 @@ static int sctp_copy_laddrs_old(struct sock *sk, __u16 port,
                                         int max_addrs, void *to,
                                         int *bytes_copied)
 {
-        struct list_head *pos, *next;
         struct sctp_sockaddr_entry *addr;
         union sctp_addr temp;
         int cnt = 0;
         int addrlen;
 
-        list_for_each_safe(pos, next, &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 ((PF_INET == sk->sk_family) &&
                     (AF_INET6 == addr->a.sa.sa_family))
                         continue;
@@ -4149,6 +4129,7 @@ static int sctp_copy_laddrs_old(struct sock *sk, __u16 port,
                 cnt ++;
                 if (cnt >= max_addrs) break;
         }
+        rcu_read_unlock();
 
         return cnt;
 }
@@ -4156,14 +4137,16 @@ static int sctp_copy_laddrs_old(struct sock *sk, __u16 port,
 static int sctp_copy_laddrs(struct sock *sk, __u16 port, void *to,
                             size_t space_left, int *bytes_copied)
 {
-        struct list_head *pos, *next;
         struct sctp_sockaddr_entry *addr;
         union sctp_addr temp;
         int cnt = 0;
         int addrlen;
 
-        list_for_each_safe(pos, next, &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 ((PF_INET == sk->sk_family) &&
                     (AF_INET6 == addr->a.sa.sa_family))
                         continue;
@@ -4171,8 +4154,10 @@ static int sctp_copy_laddrs(struct sock *sk, __u16 port, void *to,
                 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 (space_left < addrlen)
-                        return -ENOMEM;
+                if (space_left < addrlen) {
+                        cnt =  -ENOMEM;
+                        break;
+                }
                 memcpy(to, &temp, addrlen);
 
                 to += addrlen;
@@ -4180,6 +4165,7 @@ static int sctp_copy_laddrs(struct sock *sk, __u16 port, void *to,
                 space_left -= addrlen;
                 *bytes_copied += addrlen;
         }
+        rcu_read_unlock();
 
         return cnt;
 }
@@ -4192,7 +4178,6 @@ static int sctp_getsockopt_local_addrs_old(struct sock *sk, int len,
 {
         struct sctp_bind_addr *bp;
         struct sctp_association *asoc;
-        struct list_head *pos;
         int cnt = 0;
         struct sctp_getaddrs_old getaddrs;
         struct sctp_sockaddr_entry *addr;
@@ -4200,7 +4185,6 @@ static int sctp_getsockopt_local_addrs_old(struct sock *sk, int len,
         union sctp_addr temp;
         struct sctp_sock *sp = sctp_sk(sk);
         int addrlen;
-        rwlock_t *addr_lock;
         int err = 0;
         void *addrs;
         void *buf;
@@ -4222,13 +4206,11 @@ static int sctp_getsockopt_local_addrs_old(struct sock *sk, int len,
          */
         if (0 == getaddrs.assoc_id) {
                 bp = &sctp_sk(sk)->ep->base.bind_addr;
-                addr_lock = &sctp_sk(sk)->ep->base.addr_lock;
         } else {
                 asoc = sctp_id2assoc(sk, getaddrs.assoc_id);
                 if (!asoc)
                         return -EINVAL;
                 bp = &asoc->base.bind_addr;
-                addr_lock = &asoc->base.addr_lock;
         }
 
         to = getaddrs.addrs;
@@ -4242,8 +4224,6 @@ static int sctp_getsockopt_local_addrs_old(struct sock *sk, int len,
         if (!addrs)
                 return -ENOMEM;
 
-        sctp_read_lock(addr_lock);
-
         /* If the endpoint is bound to 0.0.0.0 or ::0, get the valid
          * addresses from the global local address list.
          */
@@ -4259,8 +4239,11 @@ static int sctp_getsockopt_local_addrs_old(struct sock *sk, int len,
         }
 
         buf = addrs;
-        list_for_each(pos, &bp->address_list) {
-                addr = list_entry(pos, struct sctp_sockaddr_entry, list);
+        /* Protection on the bound address list is not needed since
+         * in the socket option context we hold a socket lock and
+         * thus the bound address list can't change.
+         */
+        list_for_each_entry(addr, &bp->address_list, list) {
                 memcpy(&temp, &addr->a, sizeof(temp));
                 sctp_get_pf_specific(sk->sk_family)->addr_v4map(sp, &temp);
                 addrlen = sctp_get_af_specific(temp.sa.sa_family)->sockaddr_len;
@@ -4272,8 +4255,6 @@ static int sctp_getsockopt_local_addrs_old(struct sock *sk, int len,
         }
 
 copy_getaddrs:
-        sctp_read_unlock(addr_lock);
-
         /* copy the entire address list into the user provided space */
         if (copy_to_user(to, addrs, bytes_copied)) {
                 err = -EFAULT;
@@ -4295,7 +4276,6 @@ static int sctp_getsockopt_local_addrs(struct sock *sk, int len,
 {
         struct sctp_bind_addr *bp;
         struct sctp_association *asoc;
-        struct list_head *pos;
         int cnt = 0;
         struct sctp_getaddrs getaddrs;
         struct sctp_sockaddr_entry *addr;
@@ -4303,7 +4283,6 @@ static int sctp_getsockopt_local_addrs(struct sock *sk, int len,
         union sctp_addr temp;
         struct sctp_sock *sp = sctp_sk(sk);
         int addrlen;
-        rwlock_t *addr_lock;
         int err = 0;
         size_t space_left;
         int bytes_copied = 0;
@@ -4324,13 +4303,11 @@ static int sctp_getsockopt_local_addrs(struct sock *sk, int len,
          */
         if (0 == getaddrs.assoc_id) {
                 bp = &sctp_sk(sk)->ep->base.bind_addr;
-                addr_lock = &sctp_sk(sk)->ep->base.addr_lock;
         } else {
                 asoc = sctp_id2assoc(sk, getaddrs.assoc_id);
                 if (!asoc)
                         return -EINVAL;
                 bp = &asoc->base.bind_addr;
-                addr_lock = &asoc->base.addr_lock;
         }
 
         to = optval + offsetof(struct sctp_getaddrs,addrs);
@@ -4340,8 +4317,6 @@ static int sctp_getsockopt_local_addrs(struct sock *sk, int len,
         if (!addrs)
                 return -ENOMEM;
 
-        sctp_read_lock(addr_lock);
-
         /* If the endpoint is bound to 0.0.0.0 or ::0, get the valid
          * addresses from the global local address list.
          */
@@ -4353,21 +4328,24 @@ static int sctp_getsockopt_local_addrs(struct sock *sk, int len,
                                                 space_left, &bytes_copied);
                         if (cnt < 0) {
                                 err = cnt;
-                                goto error_lock;
+                                goto out;
                         }
                         goto copy_getaddrs;
                 }
         }
 
         buf = addrs;
-        list_for_each(pos, &bp->address_list) {
-                addr = list_entry(pos, struct sctp_sockaddr_entry, list);
+        /* Protection on the bound address list is not needed since
+         * in the socket option context we hold a socket lock and
+         * thus the bound address list can't change.
+         */
+        list_for_each_entry(addr, &bp->address_list, list) {
                 memcpy(&temp, &addr->a, sizeof(temp));
                 sctp_get_pf_specific(sk->sk_family)->addr_v4map(sp, &temp);
                 addrlen = sctp_get_af_specific(temp.sa.sa_family)->sockaddr_len;
                 if (space_left < addrlen) {
                         err =  -ENOMEM; /*fixme: right error?*/
-                        goto error_lock;
+                        goto out;
                 }
                 memcpy(buf, &temp, addrlen);
                 buf += addrlen;
@@ -4377,8 +4355,6 @@ static int sctp_getsockopt_local_addrs(struct sock *sk, int len,
         }
 
 copy_getaddrs:
-        sctp_read_unlock(addr_lock);
-
         if (copy_to_user(to, addrs, bytes_copied)) {
                 err = -EFAULT;
                 goto out;
@@ -4389,12 +4365,6 @@ copy_getaddrs:
         }
         if (put_user(bytes_copied, optlen))
                 err = -EFAULT;
-
-        goto out;
-
-error_lock:
-        sctp_read_unlock(addr_lock);
-
 out:
         kfree(addrs);
         return err;