From: Jérémie Galarneau <jeremie.galarneau@efficios.com>
Date: Fri, 11 Oct 2019 20:26:29 +0000 (-0400)
Subject: Fix: sessiond: don't assert on event creation error
X-Git-Tag: v2.12.0-rc1~310
X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=commitdiff_plain;h=e9f11505edfba881935d966c0ce09a39571a1887

Fix: sessiond: don't assert on event creation error

Don't assert if an application tracer reports that an event already
exists. This could be caused by a bug on the tracer end or memory
corruption on the application's end. In either case, an assert() is
too strict; simply report the error.

Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
---

diff --git a/src/bin/lttng-sessiond/ust-app.c b/src/bin/lttng-sessiond/ust-app.c
index aea37badb..b3251c19c 100644
--- a/src/bin/lttng-sessiond/ust-app.c
+++ b/src/bin/lttng-sessiond/ust-app.c
@@ -3142,8 +3142,19 @@ int create_ust_app_event(struct ust_app_session *ua_sess,
 	/* Create it on the tracer side */
 	ret = create_ust_event(app, ua_sess, ua_chan, ua_event);
 	if (ret < 0) {
-		/* Not found previously means that it does not exist on the tracer */
-		assert(ret != -LTTNG_UST_ERR_EXIST);
+		/*
+		 * Not found previously means that it does not exist on the
+		 * tracer. If the application reports that the event existed,
+		 * it means there is a bug in the sessiond or lttng-ust
+		 * (or corruption, etc.)
+		 */
+		if (ret == -LTTNG_UST_ERR_EXIST) {
+			ERR("Tracer for application reported that an event being created already existed: "
+					"event_name = \"%s\", pid = %d, ppid = %d, uid = %d, gid = %d",
+					uevent->attr.name,
+					app->pid, app->ppid, app->uid,
+					app->gid);
+		}
 		goto error;
 	}