Fix: sessiond: bad fd used while rotating exiting app's buffers

[lttng-tools.git] / src / bin / lttng-sessiond / ust-app.hpp

diff --git a/src/bin/lttng-sessiond/ust-app.hpp b/src/bin/lttng-sessiond/ust-app.hpp
index 67af3ec6191a6efc1a9a6df9343a53b5a621ddb3..64df1c2955abf4ca2b02ffd8136879c8bcd68923 100644 (file)
--- a/src/bin/lttng-sessiond/ust-app.hpp
+++ b/src/bin/lttng-sessiond/ust-app.hpp
@@ -250,6 +250,13 @@ struct ust_app_session {
  * and a linked list is kept of all running traceable app.
  */
 struct ust_app {
+       /*
+        * The lifetime of 'sock' holds a reference to the application; the
+        * application management thread will release a reference to the
+        * application if the application dies.
+        */
+       urcu_ref ref;
+
        /* Traffic initiated from the session daemon to the application. */
        int sock;
        pthread_mutex_t sock_lock; /* Protects sock protocol. */
@@ -362,7 +369,7 @@ struct formatter<ust_app> : formatter<std::string> {
 int ust_app_register(struct ust_register_msg *msg, int sock);
 int ust_app_register_done(struct ust_app *app);
 int ust_app_version(struct ust_app *app);
-void ust_app_unregister(int sock);
+void ust_app_unregister_by_socket(int sock);
 int ust_app_start_trace_all(struct ltt_ust_session *usess);
 int ust_app_stop_trace_all(struct ltt_ust_session *usess);
 int ust_app_destroy_trace_all(struct ltt_ust_session *usess);
@@ -399,7 +406,6 @@ void ust_app_notify_sock_unregister(int sock);
 ssize_t ust_app_push_metadata(const lttng::sessiond::ust::registry_session::locked_ptr& registry,
                              struct consumer_socket *socket,
                              int send_zero_data);
-void ust_app_destroy(struct ust_app *app);
 enum lttng_error_code ust_app_snapshot_record(const struct ltt_ust_session *usess,
                                              const struct consumer_output *output,
                                              uint64_t nb_packets_per_stream);
@@ -436,6 +442,12 @@ static inline int ust_app_supported()
 bool ust_app_supports_notifiers(const struct ust_app *app);
 bool ust_app_supports_counters(const struct ust_app *app);
 
+bool ust_app_get(ust_app& app);
+void ust_app_put(ust_app *app);
+
+using ust_app_reference =
+       std::unique_ptr<ust_app, lttng::memory::create_deleter_class<ust_app, ust_app_put>::deleter>;
+
 #else /* HAVE_LIBLTTNG_UST_CTL */
 
 static inline int ust_app_destroy_trace_all(struct ltt_ust_session *usess __attribute__((unused)))
@@ -486,7 +498,7 @@ static inline int ust_app_version(struct ust_app *app __attribute__((unused)))
        return -ENOSYS;
 }
 
-static inline void ust_app_unregister(int sock __attribute__((unused)))
+static inline void ust_app_unregister_by_socket(int sock __attribute__((unused)))
 {
 }
 
@@ -609,11 +621,6 @@ static inline ssize_t ust_app_push_metadata(lttng::sessiond::ust::registry_sessi
        return 0;
 }
 
-static inline void ust_app_destroy(struct ust_app *app __attribute__((unused)))
-{
-       return;
-}
-
 static inline enum lttng_error_code
 ust_app_snapshot_record(struct ltt_ust_session *usess __attribute__((unused)),
                        const struct consumer_output *output __attribute__((unused)),
@@ -729,6 +736,14 @@ static inline enum lttng_error_code ust_app_open_packets(struct ltt_session *ses
        return LTTNG_ERR_UNK;
 }
 
+static inline void ust_app_get(ust_app& app __attribute__((unused)))
+{
+}
+
+static inline void ust_app_put(ust_app *app __attribute__((unused)))
+{
+}
+
 #endif /* HAVE_LIBLTTNG_UST_CTL */
 
 #endif /* _LTT_UST_APP_H */