net: mqtt: Fix NULL pointer dereference in logs

MQTT packet_length_encode function accepts NULL buf argument, therefore it cannot be dereferenced without a check. Signed-off-by: Robert Lubos <[email protected]>
punitvara · Nov 28, 2018 · b5f9771 · b5f9771
1 parent a26db60
commit b5f9771
Showing 1 changed file with 2 additions and 1 deletion.
diff --git a/subsys/net/lib/mqtt_sock/mqtt_encoder.c b/subsys/net/lib/mqtt_sock/mqtt_encoder.c
@@ -153,7 +153,8 @@ static u8_t packet_length_encode(u32_t length, struct buf_ctx *buf)
 {
 	u8_t encoded_bytes = 0;
 
-	MQTT_TRC(">> length:0x%08x cur:%p, end:%p", length, buf->cur, buf->end);
+	MQTT_TRC(">> length:0x%08x cur:%p, end:%p", length,
+		 (buf == NULL) ? 0 : buf->cur, (buf == NULL) ? 0 : buf->end);
 
 	do {
 		encoded_bytes++;