NFC: LLCP connect must wait for a CC frame

Blocking sockets should sleep on a CC (Connection Complete) reception
from the connect() call.

Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 41 insertions, 1 deletions

diff --git a/net/nfc/llcp/sock.c b/net/nfc/llcp/sock.c
index c13e02ebdef9..99196d3b84eb 100644
--- a/net/nfc/llcp/sock.c
+++ b/net/nfc/llcp/sock.c
@@ -27,6 +27,42 @@
 #include "../nfc.h"
 #include "llcp.h"
 
+static int sock_wait_state(struct sock *sk, int state, unsigned long timeo)
+{
+        DECLARE_WAITQUEUE(wait, current);
+        int err = 0;
+
+        pr_debug("sk %p", sk);
+
+        add_wait_queue(sk_sleep(sk), &wait);
+        set_current_state(TASK_INTERRUPTIBLE);
+
+        while (sk->sk_state != state) {
+                if (!timeo) {
+                        err = -EINPROGRESS;
+                        break;
+                }
+
+                if (signal_pending(current)) {
+                        err = sock_intr_errno(timeo);
+                        break;
+                }
+
+                release_sock(sk);
+                timeo = schedule_timeout(timeo);
+                lock_sock(sk);
+                set_current_state(TASK_INTERRUPTIBLE);
+
+                err = sock_error(sk);
+                if (err)
+                        break;
+        }
+
+        __set_current_state(TASK_RUNNING);
+        remove_wait_queue(sk_sleep(sk), &wait);
+        return err;
+}
+
 static struct proto llcp_sock_proto = {
         .name     = "NFC_LLCP",
         .owner    = THIS_MODULE,
@@ -462,9 +498,13 @@ static int llcp_sock_connect(struct socket *sock, struct sockaddr *_addr,
         if (ret)
                 goto put_dev;
 
-        sk->sk_state = LLCP_CONNECTED;
+        ret = sock_wait_state(sk, LLCP_CONNECTED,
+                              sock_sndtimeo(sk, flags & O_NONBLOCK));
+        if (ret)
+                goto put_dev;
 
         release_sock(sk);
+
         return 0;
 
 put_dev: