Fix: Ambiguous agent event filter bytecode ownership

[lttng-tools.git] / src / bin / lttng-sessiond / cmd.c

diff --git a/src/bin/lttng-sessiond/cmd.c b/src/bin/lttng-sessiond/cmd.c
index c2b0248ea5210e4506b9086d2228b89fbf89c1ff..2dcc52b7a2aff880bdfbb1c9fc61cb8ece35c27d 100644 (file)
--- a/src/bin/lttng-sessiond/cmd.c
+++ b/src/bin/lttng-sessiond/cmd.c
@@ -16,6 +16,7 @@
  */
 
 #define _GNU_SOURCE
+#define _LGPL_SOURCE
 #include <assert.h>
 #include <inttypes.h>
 #include <urcu/list.h>
@@ -1385,6 +1386,7 @@ end:
 
 /*
  * Command LTTNG_ENABLE_EVENT processed by the client thread.
+ * We own filter, exclusion, and filter_expression.
  */
 int cmd_enable_event(struct ltt_session *session, struct lttng_domain *domain,
                char *channel_name, struct lttng_event *event,
@@ -1536,6 +1538,10 @@ int cmd_enable_event(struct ltt_session *session, struct lttng_domain *domain,
                /* At this point, the session and channel exist on the tracer */
                ret = event_ust_enable_tracepoint(usess, uchan, event,
                                filter_expression, filter, exclusion);
+               /* We have passed ownership */
+               filter_expression = NULL;
+               filter = NULL;
+               exclusion = NULL;
                if (ret != LTTNG_OK) {
                        goto error;
                }
@@ -1598,8 +1604,30 @@ int cmd_enable_event(struct ltt_session *session, struct lttng_domain *domain,
                        assert(0);
                }
 
-               ret = cmd_enable_event(session, &tmp_dom, (char *) default_chan_name,
-                       &uevent, filter_expression, filter, NULL, wpipe);
+               {
+                       struct lttng_filter_bytecode *filter_copy = NULL;
+
+                       if (filter) {
+                               filter_copy = zmalloc(
+                                       sizeof(struct lttng_filter_bytecode)
+                                       + filter->len);
+                               if (!filter_copy) {
+                                       goto error;
+                               }
+
+                               memcpy(filter_copy, filter,
+                                       sizeof(struct lttng_filter_bytecode)
+                                       + filter->len);
+                       }
+
+                       ret = cmd_enable_event(session, &tmp_dom,
+                                       (char *) default_chan_name,
+                                       &uevent, filter_expression, filter_copy,
+                                       NULL, wpipe);
+                       /* We have passed ownership */
+                       filter_expression = NULL;
+               }
+
                if (ret != LTTNG_OK && ret != LTTNG_ERR_UST_EVENT_ENABLED) {
                        goto error;
                }
@@ -1607,8 +1635,10 @@ int cmd_enable_event(struct ltt_session *session, struct lttng_domain *domain,
                /* The wild card * means that everything should be enabled. */
                if (strncmp(event->name, "*", 1) == 0 && strlen(event->name) == 1) {
                        ret = event_agent_enable_all(usess, agt, event, filter);
+                       filter = NULL;
                } else {
                        ret = event_agent_enable(usess, agt, event, filter);
+                       filter = NULL;
                }
                if (ret != LTTNG_OK) {
                        goto error;
@@ -1629,6 +1659,9 @@ int cmd_enable_event(struct ltt_session *session, struct lttng_domain *domain,
        ret = LTTNG_OK;
 
 error:
+       free(filter_expression);
+       free(filter);
+       free(exclusion);
        rcu_read_unlock();
        return ret;
 }