[PATCH AUTOSEL 4.14] nfc: Do not send datagram if socket state isn't LLCP_BOUND

[Sasha Levin]

From: Siddh Raman Pant <code@xxxxxxxx>

[ Upstream commit 6ec0d7527c4287369b52df3bcefd21a0c4fb2b7c ]

As we know we cannot send the datagram (state can be set to LLCP_CLOSED
by nfc_llcp_socket_release()), there is no need to proceed further.

Thus, bail out early from llcp_sock_sendmsg().

Signed-off-by: Siddh Raman Pant <code@xxxxxxxx>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>
Reviewed-by: Suman Ghosh <sumang@xxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 net/nfc/llcp_sock.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/net/nfc/llcp_sock.c b/net/nfc/llcp_sock.c
index 5bd6494573942..3b37c1ba93e48 100644
--- a/net/nfc/llcp_sock.c
+++ b/net/nfc/llcp_sock.c
@@ -803,6 +803,11 @@ static int llcp_sock_sendmsg(struct socket *sock, struct msghdr *msg,
 	}
 
 	if (sk->sk_type == SOCK_DGRAM) {
+		if (sk->sk_state != LLCP_BOUND) {
+			release_sock(sk);
+			return -ENOTCONN;
+		}
+
 		DECLARE_SOCKADDR(struct sockaddr_nfc_llcp *, addr,
 				 msg->msg_name);
 
-- 
2.43.0