X-Git-Url: https://git.lttng.org/?a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fmain.c;h=0e7de6e5e4786d27383eec0481a48504a84b5c04;hb=fb27f84c28e9d8ec7c8ce5ac1b541b0671a4569e;hp=6310db7e601654f5d5f3bc0c1bae41cf866c532a;hpb=772b8f4db503f0dc5ba184b2f71509eb4c718b24;p=lttng-tools.git

diff --git a/src/bin/lttng-sessiond/main.c b/src/bin/lttng-sessiond/main.c
index 6310db7e6..0e7de6e5e 100644
--- a/src/bin/lttng-sessiond/main.c
+++ b/src/bin/lttng-sessiond/main.c
@@ -586,6 +586,34 @@ static int generate_lock_file_path(char *path, size_t len)
 	return ret;
 }
 
+/*
+ * Wait on consumer process termination.
+ *
+ * Need to be called with the consumer data lock held or from a context
+ * ensuring no concurrent access to data (e.g: cleanup).
+ */
+static void wait_consumer(struct consumer_data *consumer_data)
+{
+	pid_t ret;
+	int status;
+
+	if (consumer_data->pid <= 0) {
+		return;
+	}
+
+	DBG("Waiting for complete teardown of consumerd (PID: %d)",
+			consumer_data->pid);
+	ret = waitpid(consumer_data->pid, &status, 0);
+	if (ret == -1) {
+		PERROR("consumerd waitpid pid: %d", consumer_data->pid)
+	}
+	if (!WIFEXITED(status)) {
+		ERR("consumerd termination with error: %d",
+				WEXITSTATUS(ret));
+	}
+	consumer_data->pid = 0;
+}
+
 /*
  * Cleanup the session daemon's data structures.
  */
@@ -680,6 +708,10 @@ static void sessiond_cleanup(void)
 		}
 	}
 
+	wait_consumer(&kconsumer_data);
+	wait_consumer(&ustconsumer64_data);
+	wait_consumer(&ustconsumer32_data);
+
 	DBG("Cleaning up all agent apps");
 	agent_app_ht_clean();
 
@@ -1500,7 +1532,6 @@ error:
 
 	unlink(consumer_data->err_unix_sock_path);
 	unlink(consumer_data->cmd_unix_sock_path);
-	consumer_data->pid = 0;
 	pthread_mutex_unlock(&consumer_data->lock);
 
 	/* Cleanup metadata socket mutex. */
@@ -1787,6 +1818,12 @@ static void sanitize_wait_queue(struct ust_reg_wait_queue *wait_queue)
 				wait_queue->count--;
 				ust_app_destroy(wait_node->app);
 				free(wait_node);
+				/*
+				 * Silence warning of use-after-free in
+				 * cds_list_for_each_entry_safe which uses
+				 * __typeof__(*wait_node).
+				 */
+				wait_node = NULL;
 				break;
 			}
 		}
@@ -1989,7 +2026,7 @@ static void *thread_dispatch_ust_registration(void *data)
 				 * Don't care about return value. Let the manage apps threads
 				 * handle app unregistration upon socket close.
 				 */
-				(void) ust_app_register_done(app->sock);
+				(void) ust_app_register_done(app);
 
 				/*
 				 * Even if the application socket has been closed, send the app
@@ -2935,6 +2972,8 @@ static int process_client_msg(struct command_ctx *cmd_ctx, int sock,
 
 	DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
 
+	assert(!rcu_read_ongoing());
+
 	*sock_error = 0;
 
 	switch (cmd_ctx->lsm->cmd_type) {
@@ -4022,6 +4061,7 @@ setup_error:
 		session_unlock_list();
 	}
 init_setup_error:
+	assert(!rcu_read_ongoing());
 	return ret;
 }
 
@@ -6058,6 +6098,9 @@ exit_options:
 	sessiond_cleanup_options();
 
 exit_set_signal_handler:
+	/* Ensure all prior call_rcu are done. */
+	rcu_barrier();
+
 	if (!retval) {
 		exit(EXIT_SUCCESS);
 	} else {