tipc: Don't use iocb argument in socket layer

Currently the iocb argument is used to idenfiy whether or not socket
lock is hold before tipc_sendmsg()/tipc_send_stream() is called. But
this usage prevents iocb argument from being dropped through sendmsg()
at socket common layer. Therefore, in the commit we introduce two new
functions called __tipc_sendmsg() and __tipc_send_stream(). When they
are invoked, it assumes that their callers have taken socket lock,
thereby avoiding the weird usage of iocb argument.

Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 44 insertions, 38 deletions

diff --git a/net/tipc/socket.c b/net/tipc/socket.c
index f73e975af80b..c245ec31fa4c 100644
--- a/net/tipc/socket.c
+++ b/net/tipc/socket.c
@@ -114,6 +114,9 @@ static int tipc_sk_withdraw(struct tipc_sock *tsk, uint scope,
 static struct tipc_sock *tipc_sk_lookup(struct net *net, u32 portid);
 static int tipc_sk_insert(struct tipc_sock *tsk);
 static void tipc_sk_remove(struct tipc_sock *tsk);
+static int __tipc_send_stream(struct socket *sock, struct msghdr *m,
+                              size_t dsz);
+static int __tipc_sendmsg(struct socket *sock, struct msghdr *m, size_t dsz);
 
 static const struct proto_ops packet_ops;
 static const struct proto_ops stream_ops;
@@ -907,6 +910,18 @@ static int tipc_wait_for_sndmsg(struct socket *sock, long *timeo_p)
 static int tipc_sendmsg(struct kiocb *iocb, struct socket *sock,
                         struct msghdr *m, size_t dsz)
 {
+        struct sock *sk = sock->sk;
+        int ret;
+
+        lock_sock(sk);
+        ret = __tipc_sendmsg(sock, m, dsz);
+        release_sock(sk);
+
+        return ret;
+}
+
+static int __tipc_sendmsg(struct socket *sock, struct msghdr *m, size_t dsz)
+{
         DECLARE_SOCKADDR(struct sockaddr_tipc *, dest, m->msg_name);
         struct sock *sk = sock->sk;
         struct tipc_sock *tsk = tipc_sk(sk);
@@ -931,22 +946,13 @@ static int tipc_sendmsg(struct kiocb *iocb, struct socket *sock,
         if (dsz > TIPC_MAX_USER_MSG_SIZE)
                 return -EMSGSIZE;
 
-        if (iocb)
-                lock_sock(sk);
-
         if (unlikely(sock->state != SS_READY)) {
-                if (sock->state == SS_LISTENING) {
-                        rc = -EPIPE;
-                        goto exit;
-                }
-                if (sock->state != SS_UNCONNECTED) {
-                        rc = -EISCONN;
-                        goto exit;
-                }
-                if (tsk->published) {
-                        rc = -EOPNOTSUPP;
-                        goto exit;
-                }
+                if (sock->state == SS_LISTENING)
+                        return -EPIPE;
+                if (sock->state != SS_UNCONNECTED)
+                        return -EISCONN;
+                if (tsk->published)
+                        return -EOPNOTSUPP;
                 if (dest->addrtype == TIPC_ADDR_NAME) {
                         tsk->conn_type = dest->addr.name.name.type;
                         tsk->conn_instance = dest->addr.name.name.instance;
@@ -956,8 +962,7 @@ static int tipc_sendmsg(struct kiocb *iocb, struct socket *sock,
         timeo = sock_sndtimeo(sk, m->msg_flags & MSG_DONTWAIT);
 
         if (dest->addrtype == TIPC_ADDR_MCAST) {
-                rc = tipc_sendmcast(sock, seq, m, dsz, timeo);
-                goto exit;
+                return tipc_sendmcast(sock, seq, m, dsz, timeo);
         } else if (dest->addrtype == TIPC_ADDR_NAME) {
                 u32 type = dest->addr.name.name.type;
                 u32 inst = dest->addr.name.name.instance;
@@ -972,10 +977,8 @@ static int tipc_sendmsg(struct kiocb *iocb, struct socket *sock,
                 dport = tipc_nametbl_translate(net, type, inst, &dnode);
                 msg_set_destnode(mhdr, dnode);
                 msg_set_destport(mhdr, dport);
-                if (unlikely(!dport && !dnode)) {
-                        rc = -EHOSTUNREACH;
-                        goto exit;
-                }
+                if (unlikely(!dport && !dnode))
+                        return -EHOSTUNREACH;
         } else if (dest->addrtype == TIPC_ADDR_ID) {
                 dnode = dest->addr.id.node;
                 msg_set_type(mhdr, TIPC_DIRECT_MSG);
@@ -990,7 +993,7 @@ new_mtu:
         mtu = tipc_node_get_mtu(net, dnode, tsk->portid);
         rc = tipc_msg_build(mhdr, m, 0, dsz, mtu, pktchain);
         if (rc < 0)
-                goto exit;
+                return rc;
 
         do {
                 skb = skb_peek(pktchain);
@@ -1013,9 +1016,6 @@ new_mtu:
                 if (rc)
                         __skb_queue_purge(pktchain);
         } while (!rc);
-exit:
-        if (iocb)
-                release_sock(sk);
 
         return rc;
 }
@@ -1066,6 +1066,18 @@ static int tipc_send_stream(struct kiocb *iocb, struct socket *sock,
                             struct msghdr *m, size_t dsz)
 {
         struct sock *sk = sock->sk;
+        int ret;
+
+        lock_sock(sk);
+        ret = __tipc_send_stream(sock, m, dsz);
+        release_sock(sk);
+
+        return ret;
+}
+
+static int __tipc_send_stream(struct socket *sock, struct msghdr *m, size_t dsz)
+{
+        struct sock *sk = sock->sk;
         struct net *net = sock_net(sk);
         struct tipc_sock *tsk = tipc_sk(sk);
         struct tipc_msg *mhdr = &tsk->phdr;
@@ -1080,7 +1092,7 @@ static int tipc_send_stream(struct kiocb *iocb, struct socket *sock,
 
         /* Handle implied connection establishment */
         if (unlikely(dest)) {
-                rc = tipc_sendmsg(iocb, sock, m, dsz);
+                rc = __tipc_sendmsg(sock, m, dsz);
                 if (dsz && (dsz == rc))
                         tsk->sent_unacked = 1;
                 return rc;
@@ -1088,15 +1100,11 @@ static int tipc_send_stream(struct kiocb *iocb, struct socket *sock,
         if (dsz > (uint)INT_MAX)
                 return -EMSGSIZE;
 
-        if (iocb)
-                lock_sock(sk);
-
         if (unlikely(sock->state != SS_CONNECTED)) {
                 if (sock->state == SS_DISCONNECTING)
-                        rc = -EPIPE;
+                        return -EPIPE;
                 else
-                        rc = -ENOTCONN;
-                goto exit;
+                        return -ENOTCONN;
         }
 
         timeo = sock_sndtimeo(sk, m->msg_flags & MSG_DONTWAIT);
@@ -1108,7 +1116,7 @@ next:
         send = min_t(uint, dsz - sent, TIPC_MAX_USER_MSG_SIZE);
         rc = tipc_msg_build(mhdr, m, sent, send, mtu, pktchain);
         if (unlikely(rc < 0))
-                goto exit;
+                return rc;
         do {
                 if (likely(!tsk_conn_cong(tsk))) {
                         rc = tipc_link_xmit(net, pktchain, dnode, portid);
@@ -1133,9 +1141,7 @@ next:
                 if (rc)
                         __skb_queue_purge(pktchain);
         } while (!rc);
-exit:
-        if (iocb)
-                release_sock(sk);
+
         return sent ? sent : rc;
 }
 
@@ -1947,7 +1953,7 @@ static int tipc_connect(struct socket *sock, struct sockaddr *dest,
                 if (!timeout)
                         m.msg_flags = MSG_DONTWAIT;
 
-                res = tipc_sendmsg(NULL, sock, &m, 0);
+                res = __tipc_sendmsg(sock, &m, 0);
                 if ((res < 0) && (res != -EWOULDBLOCK))
                         goto exit;
 
@@ -2103,7 +2109,7 @@ static int tipc_accept(struct socket *sock, struct socket *new_sock, int flags)
                 struct msghdr m = {NULL,};
 
                 tsk_advance_rx_queue(sk);
-                tipc_send_packet(NULL, new_sock, &m, 0);
+                __tipc_send_stream(new_sock, &m, 0);
         } else {
                 __skb_dequeue(&sk->sk_receive_queue);
                 __skb_queue_head(&new_sk->sk_receive_queue, buf);