samples: bluetooth: Fix PAwR null dereference on disconnection

If an involuntary disconnection happened it could set default_conn to NULL
while it was still being used in the main while loop.

Signed-off-by: Hakan Jansson <[email protected]>

Author: hakanjansson

samples/bluetooth/periodic_adv_rsp/src/main.c

@@ -20,6 +20,13 @@ static K_SEM_DEFINE(sem_discovered, 0, 1);
 static K_SEM_DEFINE(sem_written, 0, 1);
 static K_SEM_DEFINE(sem_disconnected, 0, 1);
 
+struct k_poll_event events[] = {
+	K_POLL_EVENT_STATIC_INITIALIZER(K_POLL_TYPE_SEM_AVAILABLE, K_POLL_MODE_NOTIFY_ONLY,
+					&sem_connected, 0),
+	K_POLL_EVENT_STATIC_INITIALIZER(K_POLL_TYPE_SEM_AVAILABLE, K_POLL_MODE_NOTIFY_ONLY,
+					&sem_disconnected, 0),
+};
+
 static struct bt_uuid_128 pawr_char_uuid =
 	BT_UUID_INIT_128(BT_UUID_128_ENCODE(0x12345678, 0x1234, 0x5678, 0x1234, 0x56789abcdef1));
 static uint16_t pawr_attr_handle;
@@ -116,9 +123,6 @@ void disconnected_cb(struct bt_conn *conn, uint8_t reason)
 {
 	printk("Disconnected, reason 0x%02X %s\n", reason, bt_hci_err_to_str(reason));
 
-	bt_conn_unref(default_conn);
-	default_conn = NULL;
-
 	k_sem_give(&sem_disconnected);
 }
 
@@ -303,7 +307,14 @@ int main(void)
 
 		printk("Scanning successfully started\n");
 
-		k_sem_take(&sem_connected, K_FOREVER);
+		/* Wait for either remote info available or involuntary disconnect */
+		k_poll(events, ARRAY_SIZE(events), K_FOREVER);
+		err = k_sem_take(&sem_connected, K_NO_WAIT);
+		if (err) {
+			printk("Disconnected before remote info available\n");
+
+			goto disconnected;
+		}
 
 		err = bt_le_per_adv_set_info_transfer(pawr_adv, default_conn, 0);
 		if (err) {
@@ -373,11 +384,15 @@ int main(void)
 		k_sleep(K_MSEC(per_adv_params.interval_max * 2));
 
 		err = bt_conn_disconnect(default_conn, BT_HCI_ERR_REMOTE_USER_TERM_CONN);
-		if (err) {
+		if (err != 0 && err != -ENOTCONN) {
 			return 0;
 		}
 
+disconnected:
 		k_sem_take(&sem_disconnected, K_FOREVER);
+
+		bt_conn_unref(default_conn);
+		default_conn = NULL;
 	}
 
 	printk("Maximum numnber of syncs onboarded\n");