Fix deadlock issue

- An application can cause a deadlock if it uses a mutex lock within a callback.

Change-Id: I7d71961a2622dfd763120eacdd63c7e81afe897d
Signed-off-by: Inkyun Kil <inkyun.kil@samsung.com>

1 files changed, 87 insertions, 68 deletions

diff --git a/src/message_port_remote.c b/src/message_port_remote.c
index 31463fc..18458d1 100644
--- a/src/message_port_remote.c
+++ b/src/message_port_remote.c
@@ -326,10 +326,13 @@ static gboolean __socket_request_handler(GIOChannel *gio,
 	int fd = 0;
 	message_port_callback_info_s *callback_info;
 	message_port_pkt_s *pkt = NULL;
-	message_port_local_port_info_s *local_port_info;
 	bundle *kb = NULL;
 	bool ret = true;
 	bool existed = true;
+	int copied_local_id = 0;
+	char *copied_remote_app_id = NULL;
+	void *user_data = NULL;
+	message_port_message_cb callback = NULL;
 
 	callback_info = (message_port_callback_info_s *)data;
 	if (callback_info == NULL)
@@ -339,21 +342,29 @@ static gboolean __socket_request_handler(GIOChannel *gio,
 	if (__validate_callback_info(callback_info) == false) {
 		ret = FALSE;
 		existed = FALSE;
+		message_port_unlock_mutex();
 		goto out;
 	}
 
 	if (__validate_local_info(callback_info->local_id) == false) {
 		ret = FALSE;
+		message_port_unlock_mutex();
 		goto out;
 	}
 
-	local_port_info = callback_info->local_info;
-	if (local_port_info == NULL || local_port_info->callback == NULL) {
-		_LOGE("Failed to get callback info");
+	user_data = callback_info->local_info->user_data;
+	callback = callback_info->local_info->callback;
+	copied_local_id = callback_info->local_id;
+	copied_remote_app_id = strdup(callback_info->remote_app_id);
+	if (copied_remote_app_id == NULL) {
+		_LOGE("Failed to copy remote app id");
 		ret = FALSE;
+		message_port_unlock_mutex();
 		goto out;
 	}
 
+	message_port_unlock_mutex();
+
 	if (cond == G_IO_HUP) {
 		_LOGI("socket G_IO_HUP");
 		ret = FALSE;
@@ -382,13 +393,11 @@ static gboolean __socket_request_handler(GIOChannel *gio,
 	}
 
 	if (pkt->is_bidirection)
-		local_port_info->callback(callback_info->local_id,
-				callback_info->remote_app_id, pkt->remote_port_name,
-				pkt->is_trusted, kb, local_port_info->user_data);
+		callback(copied_local_id, copied_remote_app_id, pkt->remote_port_name,
+				pkt->is_trusted, kb, user_data);
 	else
-		local_port_info->callback(callback_info->local_id,
-				callback_info->remote_app_id, NULL,
-				pkt->is_trusted, kb, local_port_info->user_data);
+		callback(copied_local_id, copied_remote_app_id, NULL, pkt->is_trusted, kb,
+				user_data);
 
 	bundle_free(kb);
 
@@ -401,10 +410,14 @@ out:
 		free(pkt);
 	}
 
-	if (ret == FALSE && existed == TRUE)
+	if (ret == FALSE && existed == TRUE) {
+		message_port_lock_mutex();
 		__callback_info_free_by_info(callback_info);
+		message_port_unlock_mutex();
+	}
 
-	message_port_unlock_mutex();
+	if (copied_remote_app_id)
+		free(copied_remote_app_id);
 
 	return ret;
 }
@@ -488,7 +501,7 @@ static void __callback_info_update_user_data(int local_id, message_port_message_
 /* LCOV_EXCL_STOP */
 }
 
-static bool __receive_message(GVariant *parameters, GDBusMethodInvocation *invocation)
+static void __receive_message(GVariant *parameters, GDBusMethodInvocation *invocation)
 {
 	char *local_port = NULL;
 	char *local_appid = NULL;
@@ -504,6 +517,9 @@ static bool __receive_message(GVariant *parameters, GDBusMethodInvocation *invoc
 	message_port_local_port_info_s *mi;
 	int local_reg_id = 0;
 	message_port_callback_info_s *callback_info = NULL;
+	void *user_data = NULL;
+	int copied_local_id = 0;
+	message_port_message_cb callback = NULL;
 
 	char buf[1024];
 	GDBusMessage *msg;
@@ -511,53 +527,64 @@ static bool __receive_message(GVariant *parameters, GDBusMethodInvocation *invoc
 	int fd_len;
 	int *returned_fds = NULL;
 	int fd;
-	bool ret = false;
 	char *key_appid;
 
-	message_port_lock_mutex();
 	g_variant_get(parameters, "(&s&sbb&s&sbu&s)", &local_appid, &local_port, &local_trusted, &bi_dir,
 			&remote_appid, &remote_port, &remote_trusted, &len, &raw);
 
 	if (!remote_port) {
 		_LOGE("Invalid argument : remote_port is NULL");
-		goto out;
+		return;
 	}
+
 	if (!remote_appid) {
 		_LOGE("Invalid argument : remote_appid is NULL");
-		goto out;
+		return;
+	}
+
+	if (strcmp(remote_appid, app_id) != 0) {
+		_LOGE("Invalid argument : remote_appid (%s)", remote_appid);
+		return;
+	}
+
+		if (!local_port) {
+		_LOGE("Invalid argument : local_port");
+		return;
 	}
 
 	if (!local_appid) {
 		_LOGE("Invalid argument : local_appid");
-		goto out;
+		return;
 	}
 
-	if (!is_local_port_registed(remote_port, remote_trusted, &local_reg_id, &mi)) {
-		_LOGE("Invalid argument : remote_port:(%s) trusted(%d)", remote_port, remote_trusted);
-		goto out;
+	if (!len) {
+		_LOGE("Invalid argument : data_len");
+		return;
 	}
 
-	callback_info = __create_callback_info(mi, local_appid);
-	if (callback_info == NULL) {
-		goto out;
+	data = bundle_decode(raw, len);
+	if (!data) {
+		_LOGE("Invalid argument : message");
+		return;
 	}
 
-	if (!local_port) {
-		_LOGE("Invalid argument : local_port");
-		goto out;
-	}
-	if (strcmp(remote_appid, app_id) != 0) {
-		_LOGE("Invalid argument : remote_appid (%s)", remote_appid);
-		goto out;
+	message_port_lock_mutex();
+	if (!is_local_port_registed(remote_port, remote_trusted, &local_reg_id, &mi)) {
+		_LOGE("Invalid argument : remote_port:(%s) trusted(%d)", remote_port, remote_trusted);
+		message_port_unlock_mutex();
+		return;
 	}
-	if (strcmp(remote_port, callback_info->local_info->port_name) != 0) {
+
+	copied_local_id = mi->local_id;
+	user_data = mi->user_data;
+	callback = mi->callback;
+
+	if (strcmp(remote_port, mi->port_name) != 0) {
 		_LOGE("Invalid argument : remote_port (%s)", remote_port);
-		goto out;
-	}
-	if (!len) {
-		_LOGE("Invalid argument : data_len");
-		goto out;
+		message_port_unlock_mutex();
+		return;
 	}
+
 	if (remote_trusted) {
 /* LCOV_EXCL_START */
 		if (g_hash_table_lookup(__trusted_app_list_hash, (gpointer)local_appid) == NULL) {
@@ -570,30 +597,14 @@ static bool __receive_message(GVariant *parameters, GDBusMethodInvocation *invoc
 				} else {
 					_LOGE("The application (%s) is not signed with the same certificate",
 							local_appid);
-					goto out;
+					message_port_unlock_mutex();
+					return;
 				}
 			}
 		}
 /* LCOV_EXCL_STOP */
 	}
 
-	data = bundle_decode(raw, len);
-	if (!data) {
-		_LOGE("Invalid argument : message");
-		goto out;
-	}
-
-	LOGD("call calback %s", local_appid);
-	if (bi_dir)
-		callback_info->local_info->callback(callback_info->local_info->local_id,
-			local_appid, local_port, local_trusted, data, callback_info->local_info->user_data);
-	else
-		callback_info->local_info->callback(callback_info->local_info->local_id,
-			local_appid, NULL, false, data, callback_info->local_info->user_data);
-	bundle_free(data);
-
-	ret = true;
-
 	msg = g_dbus_method_invocation_get_message(invocation);
 	fd_list = g_dbus_message_get_unix_fd_list(msg);
 
@@ -602,18 +613,25 @@ static bool __receive_message(GVariant *parameters, GDBusMethodInvocation *invoc
 		returned_fds = g_unix_fd_list_steal_fds(fd_list, &fd_len);
 		if (returned_fds == NULL) {
 			_LOGE("fail to get fds");
-			ret = false;
-			goto out;
+			goto cb;
 		}
 		fd = returned_fds[0];
+		g_free(returned_fds);
 
 		LOGI("g_unix_fd_list_get %d fd: [%d]", fd_len, fd);
 		if (fd > 0) {
+			callback_info = __create_callback_info(mi, local_appid);
+			if (callback_info == NULL) {
+				close(fd);
+				goto cb;
+			}
+
 			callback_info->gio_read = g_io_channel_unix_new(fd);
 			if (!callback_info->gio_read) {
 				_LOGE("Error is %s\n", strerror_r(errno, buf, sizeof(buf)));
-				ret = false;
-				goto out;
+				__callback_info_free(callback_info);
+				close(fd);
+				goto cb;
 			}
 
 			callback_info->g_src_id = g_io_add_watch_full(
@@ -624,22 +642,23 @@ static bool __receive_message(GVariant *parameters, GDBusMethodInvocation *invoc
 					NULL);
 			if (callback_info->g_src_id == 0) {
 				_LOGE("fail to add watch on socket");
-				ret = false;
-				goto out;
+				__callback_info_free(callback_info);
+				goto cb;
 			}
 			__callback_info_append(callback_info);
 		}
 	}
 
-out:
+cb:
 	message_port_unlock_mutex();
-	if (ret == false)
-		__callback_info_free(callback_info);
 
-	if (returned_fds)
-		g_free(returned_fds);
-
-	return ret;
+	LOGD("call calback %s", local_appid);
+	if (bi_dir)
+		callback(copied_local_id, local_appid, local_port, local_trusted, data,
+				user_data);
+	else
+		callback(copied_local_id, local_appid, NULL, false, data, user_data);
+	bundle_free(data);
 }
 
 static void __on_sender_name_appeared(GDBusConnection *connection,