Fix missing locks on `mosq->state`.

Closes #1374. Thanks to Jeff Trull.

ChangeLog.txt

@@ -14,6 +14,7 @@ Broker:
 Client library:
 - Fix reconnect backoff for the situation where connections are dropped rather
   than refused. Closes #737.
+- Fix missing locks on `mosq->state`. Closes #1374.
 
 Documentation:
 - Improve details on global/per listener options in the mosquitto.conf man page.

lib/handle_ping.c

@@ -53,9 +53,15 @@ int handle__pingreq(struct mosquitto *mosq)
 
 int handle__pingresp(struct mosquitto *mosq)
 {
+	int state;
+
 	assert(mosq);
 
-	if(mosq->state != mosq_cs_connected){
+	pthread_mutex_lock(&mosq->state_mutex);
+	state = mosq->state;
+	pthread_mutex_unlock(&mosq->state_mutex);
+
+	if(state != mosq_cs_connected){
 		return MOSQ_ERR_PROTOCOL;
 	}
 

lib/handle_pubackcomp.c

@@ -47,10 +47,15 @@ int handle__pubackcomp(struct mosquitto *mosq, const char *type)
 	int rc;
 	mosquitto_property *properties = NULL;
 	int qos;
+	int state;
 
 	assert(mosq);
 
-	if(mosq->state != mosq_cs_connected){
+	pthread_mutex_lock(&mosq->state_mutex);
+	state = mosq->state;
+	pthread_mutex_unlock(&mosq->state_mutex);
+
+	if(state != mosq_cs_connected){
 		return MOSQ_ERR_PROTOCOL;
 	}
 

lib/handle_publish.c

@@ -40,10 +40,15 @@ int handle__publish(struct mosquitto *mosq)
 	uint16_t mid;
 	int slen;
 	mosquitto_property *properties = NULL;
+	int state;
 
 	assert(mosq);
 
-	if(mosq->state != mosq_cs_connected){
+	pthread_mutex_lock(&mosq->state_mutex);
+	state = mosq->state;
+	pthread_mutex_unlock(&mosq->state_mutex);
+
+	if(state != mosq_cs_connected){
 		return MOSQ_ERR_PROTOCOL;
 	}
 

lib/handle_suback.c

@@ -40,10 +40,15 @@ int handle__suback(struct mosquitto *mosq)
 	int i = 0;
 	int rc;
 	mosquitto_property *properties = NULL;
+	int state;
 
 	assert(mosq);
 
-	if(mosq->state != mosq_cs_connected){
+	pthread_mutex_lock(&mosq->state_mutex);
+	state = mosq->state;
+	pthread_mutex_unlock(&mosq->state_mutex);
+
+	if(state != mosq_cs_connected){
 		return MOSQ_ERR_PROTOCOL;
 	}
 

lib/packet_mosq.c

@@ -202,6 +202,7 @@ int packet__write(struct mosquitto *mosq)
 {
 	ssize_t write_length;
 	struct mosquitto__packet *packet;
+	int state;
 
 	if(!mosq) return MOSQ_ERR_INVAL;
 	if(mosq->sock == INVALID_SOCKET) return MOSQ_ERR_NO_CONN;
@@ -217,10 +218,14 @@ int packet__write(struct mosquitto *mosq)
 	}
 	pthread_mutex_unlock(&mosq->out_packet_mutex);
 
+	pthread_mutex_lock(&mosq->state_mutex);
+	state = mosq->state;
+	pthread_mutex_unlock(&mosq->state_mutex);
+
 #if defined(WITH_TLS) && !defined(WITH_BROKER)
-	if((mosq->state == mosq_cs_connect_pending) || mosq->want_connect){
+	if((state == mosq_cs_connect_pending) || mosq->want_connect){
 #else
-	if(mosq->state == mosq_cs_connect_pending){
+	if(state == mosq_cs_connect_pending){
 #endif
 		pthread_mutex_unlock(&mosq->current_out_packet_mutex);
 		return MOSQ_ERR_SUCCESS;
@@ -316,6 +321,7 @@ int packet__read(struct mosquitto *mosq)
 	uint8_t byte;
 	ssize_t read_length;
 	int rc = 0;
+	int state;
 
 	if(!mosq){
 		return MOSQ_ERR_INVAL;
@@ -323,7 +329,11 @@ int packet__read(struct mosquitto *mosq)
 	if(mosq->sock == INVALID_SOCKET){
 		return MOSQ_ERR_NO_CONN;
 	}
-	if(mosq->state == mosq_cs_connect_pending){
+	pthread_mutex_lock(&mosq->state_mutex);
+	state = mosq->state;
+	pthread_mutex_unlock(&mosq->state_mutex);
+
+	if(state == mosq_cs_connect_pending){
 		return MOSQ_ERR_SUCCESS;
 	}
 

lib/util_mosq.c

@@ -68,6 +68,7 @@ int mosquitto__check_keepalive(struct mosquitto *mosq)
 #ifndef WITH_BROKER
 	int rc;
 #endif
+	int state;
 
 	assert(mosq);
 #if defined(WITH_BROKER) && defined(WITH_BRIDGE)
@@ -88,7 +89,11 @@ int mosquitto__check_keepalive(struct mosquitto *mosq)
 	if(mosq->keepalive && mosq->sock != INVALID_SOCKET &&
 			(now >= next_msg_out || now - last_msg_in >= mosq->keepalive)){
 
-		if(mosq->state == mosq_cs_connected && mosq->ping_t == 0){
+		pthread_mutex_lock(&mosq->state_mutex);
+		state = mosq->state;
+		pthread_mutex_unlock(&mosq->state_mutex);
+
+		if(state == mosq_cs_connected && mosq->ping_t == 0){
 			send__pingreq(mosq);
 			/* Reset last msg times to give the server time to send a pingresp */
 			pthread_mutex_lock(&mosq->msgtime_mutex);