caif: Fix for a race in socket transmit with flow control.

Kill faulty checks on flow-off leading to connection drop at race conditions.
caif_socket checks for flow-on before transmitting and goes to sleep or
return -EAGAIN upon flow stop. Remove faulty subsequent checks on flow-off
leading to connection drop. Also fix memory leaks on some of the errors paths.

Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/caif/cfdgml.c

@@ -86,12 +86,17 @@ static int cfdgml_transmit(struct cflayer *layr, struct cfpkt *pkt)
 	struct caif_payload_info *info;
 	struct cfsrvl *service = container_obj(layr);
 	int ret;
-	if (!cfsrvl_ready(service, &ret))
+
+	if (!cfsrvl_ready(service, &ret)) {
+		cfpkt_destroy(pkt);
 		return ret;
+	}
 
 	/* STE Modem cannot handle more than 1500 bytes datagrams */
-	if (cfpkt_getlen(pkt) > DGM_MTU)
+	if (cfpkt_getlen(pkt) > DGM_MTU) {
+		cfpkt_destroy(pkt);
 		return -EMSGSIZE;
+	}
 
 	cfpkt_add_head(pkt, &zero, 3);
 	packet_type = 0x08; /* B9 set - UNCLASSIFIED */