From: Jérémie Galarneau <jeremie.galarneau@efficios.com>
Date: Sat, 12 Jan 2019 19:53:56 +0000 (-0500)
Subject: Fix: leak of filter bytecode and expression on agent event re-enable
X-Git-Tag: v2.10.6~3
X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=5e28af3877ffdb24d0462d9a4ba77f2128cf9cc7;p=lttng-tools.git

Fix: leak of filter bytecode and expression on agent event re-enable

The agent subsystem does not properly assume the clean-up of an
event's filter bytecode and expression when a previously disabled
event is re-enabled.

This change ensures that the ownership of both the filter bytecode
and expression is assumed by the agent subsystem and discarded
when a matching event is found.

Steps to reproduce the leak:
$ lttng create
$ lttng enable-event --python allo --filter 'a[42] == 241'
$ lttng disable-event --python allo
$ lttng enable-event --python allo --filter 'a[42] == 241'

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

diff --git a/src/bin/lttng-sessiond/event.c b/src/bin/lttng-sessiond/event.c
index b7b80d366..e2c4c553f 100644
--- a/src/bin/lttng-sessiond/event.c
+++ b/src/bin/lttng-sessiond/event.c
@@ -512,12 +512,14 @@ int event_agent_enable(struct ltt_ust_session *usess,
 			ret = LTTNG_ERR_NOMEM;
 			goto error;
 		}
-
+		filter = NULL;
+		filter_expression = NULL;
 		created = 1;
 	}
 
 	/* Already enabled? */
 	if (aevent->enabled) {
+		ret = LTTNG_OK;
 		goto end;
 	}
 
@@ -538,13 +540,16 @@ int event_agent_enable(struct ltt_ust_session *usess,
 		agent_add_event(aevent, agt);
 	}
 
-end:
-	return LTTNG_OK;
+	ret = LTTNG_OK;
+	goto end;
 
 error:
 	if (created) {
 		agent_destroy_event(aevent);
 	}
+end:
+	free(filter);
+	free(filter_expression);
 	return ret;
 }