Fix: Missing rcu_read_lock in get_session_max_subbuf_size()

[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 8c13c2dd6aa24414c6a6ee61c3999afe11f68933..2c6f6f4a7bcb443d4a7e6638e489bd04d395e8bc 100644 (file)
--- a/src/bin/lttng-sessiond/cmd.c
+++ b/src/bin/lttng-sessiond/cmd.c
@@ -1604,11 +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);
-               /* We have passed ownership */
-               filter_expression = NULL;
-               filter = NULL;
+               {
+                       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;
                }
@@ -1616,8 +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;
@@ -3033,12 +3054,14 @@ static uint64_t get_session_max_subbuf_size(struct ltt_session *session)
                struct ltt_ust_channel *uchan;
                struct ltt_ust_session *usess = session->ust_session;
 
+               rcu_read_lock();
                cds_lfht_for_each_entry(usess->domain_global.channels->ht, &iter.iter,
                                uchan, node.node) {
                        if (uchan->attr.subbuf_size > max_size) {
                                max_size = uchan->attr.subbuf_size;
                        }
                }
+               rcu_read_unlock();
        }
 
        return max_size;