X-Git-Url: https://git.lttng.org/?a=blobdiff_plain;ds=sidebyside;f=src%2Fbin%2Flttng-sessiond%2Fust-app.c;h=335c20ff18556f6df3705be8be6440ff14b1f00e;hb=9bc07046c0e2a572eb3821e276949537614f74e0;hp=77888048794c39d2cdd329122eccb3af633da39f;hpb=8005f29ac9f079b844b3e6bb0261e19a76ccd4da;p=lttng-tools.git

diff --git a/src/bin/lttng-sessiond/ust-app.c b/src/bin/lttng-sessiond/ust-app.c
index 778880487..335c20ff1 100644
--- a/src/bin/lttng-sessiond/ust-app.c
+++ b/src/bin/lttng-sessiond/ust-app.c
@@ -865,6 +865,8 @@ static struct ust_app_session *create_ust_app_session(
 		ret = ustctl_create_session(app->key.sock);
 		if (ret < 0) {
 			ERR("Creating session for app pid %d", app->key.pid);
+			/* This means that the tracer is gone... */
+			ua_sess = (void*) -1UL;
 			goto error;
 		}
 
@@ -1275,6 +1277,13 @@ int ust_app_register(struct ust_register_msg *msg, int sock)
 		close(sock);
 		return -EINVAL;
 	}
+	if (msg->major != LTTNG_UST_COMM_MAJOR) {
+		ERR("Registration failed: application \"%s\" (pid: %d) has "
+			"communication protocol version %u.%u, but sessiond supports 2.x.\n",
+			msg->name, msg->pid, msg->major, msg->minor);
+		close(sock);
+		return -EINVAL;
+	}
 	lta = zmalloc(sizeof(struct ust_app));
 	if (lta == NULL) {
 		PERROR("malloc");
@@ -1750,8 +1759,11 @@ int ust_app_create_channel_glb(struct ltt_ust_session *usess,
 		 */
 		ua_sess = create_ust_app_session(usess, app);
 		if (ua_sess == NULL) {
-			/* Major problem here and it's maybe the tracer or malloc() */
+			/* The malloc() failed. */
 			goto error;
+		} else if (ua_sess == (void *) -1UL) {
+			/* The application's socket is not valid. Contiuing */
+			continue;
 		}
 
 		/* Create channel onto application */
@@ -2025,10 +2037,12 @@ int ust_app_stop_trace(struct ltt_ust_session *usess, struct ust_app *app)
 		goto error_rcu_unlock;
 	}
 
-	/* Not started, continuing. */
-	if (ua_sess->started == 0) {
-		goto end;
-	}
+	/*
+	 * If started = 0, it means that stop trace has been called for a session
+	 * that was never started. This is a code flow error and should never
+	 * happen.
+	 */
+	assert(ua_sess->started == 1);
 
 	/* This inhibits UST tracing */
 	ret = ustctl_stop_session(app->key.sock, ua_sess->handle);
@@ -2059,8 +2073,6 @@ int ust_app_stop_trace(struct ltt_ust_session *usess, struct ust_app *app)
 				ret);
 	}
 
-	ua_sess->started = 0;
-
 end:
 	rcu_read_unlock();
 	return 0;