NFC: llcp: Fix non blocking sockets connections

Without the new LLCP_CONNECTING state, non blocking sockets will be
woken up with a POLLHUP right after calling connect() because their
state is stuck at LLCP_CLOSED.
That prevents userspace from implementing any proper non blocking
socket based NFC p2p client.

Cc: stable@vger.kernel.org
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

diff --git a/net/nfc/llcp.h b/net/nfc/llcp.h
index 71f649e5ef495fd289f506dd1f8313d5dc54af35..f4d48b57ea113467807d0dd7517c4263bcd64939 100644 (file)
--- a/net/nfc/llcp.h
+++ b/net/nfc/llcp.h
@@ -19,6 +19,7 @@
 
 enum llcp_state {
        LLCP_CONNECTED = 1, /* wait_for_packet() wants that */
+       LLCP_CONNECTING,
        LLCP_DISCONNECTING,
        LLCP_CLOSED,
        LLCP_BOUND,

diff --git a/net/nfc/llcp_sock.c b/net/nfc/llcp_sock.c
index 47e7acfc0236952cbc9dc502df42c255a4232fae..d308402b67d80c192c948aa6db05c15089cfdbe8 100644 (file)
--- a/net/nfc/llcp_sock.c
+++ b/net/nfc/llcp_sock.c
@@ -571,7 +571,7 @@ static unsigned int llcp_sock_poll(struct file *file, struct socket *sock,
        if (sk->sk_shutdown == SHUTDOWN_MASK)
                mask |= POLLHUP;
 
-       if (sock_writeable(sk))
+       if (sock_writeable(sk) && sk->sk_state == LLCP_CONNECTED)
                mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
        else
                set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
@@ -729,14 +729,16 @@ static int llcp_sock_connect(struct socket *sock, struct sockaddr *_addr,
        if (ret)
                goto sock_unlink;
 
+       sk->sk_state = LLCP_CONNECTING;
+
        ret = sock_wait_state(sk, LLCP_CONNECTED,
                              sock_sndtimeo(sk, flags & O_NONBLOCK));
-       if (ret)
+       if (ret && ret != -EINPROGRESS)
                goto sock_unlink;
 
        release_sock(sk);
 
-       return 0;
+       return ret;
 
 sock_unlink:
        nfc_llcp_put_ssap(local, llcp_sock->ssap);