}
int cmd_register_trigger(struct command_ctx *cmd_ctx, int sock,
- struct notification_thread_handle *notification_thread)
+ struct notification_thread_handle *notification_thread,
+ struct lttng_trigger **return_trigger)
{
int ret;
size_t trigger_len;
}
}
- /* Set the trigger credential */
- lttng_trigger_set_credentials(trigger, &cmd_creds);
+ /*
+ * Validate the trigger credentials against the command credentials.
+ * Only the root user can register a trigger with non-matching
+ * credentials.
+ */
+ if (!lttng_credentials_is_equal_uid(
+ lttng_trigger_get_credentials(trigger),
+ &cmd_creds)) {
+ if (lttng_credentials_get_uid(&cmd_creds) != 0) {
+ ERR("Trigger credentials do not match the command credentials");
+ ret = LTTNG_ERR_INVALID_TRIGGER;
+ goto end;
+ }
+ }
- /* Inform the notification thread */
+ /*
+ * A reference to the trigger is acquired by the notification thread.
+ * It is safe to return the same trigger to the caller since it the
+ * other user holds a reference.
+ *
+ * The trigger is modified during the execution of the
+ * "register trigger" command. However, by the time the command returns,
+ * it is safe to use without any locking as its properties are
+ * immutable.
+ */
ret = notification_thread_command_register_trigger(notification_thread,
trigger);
+ if (ret != LTTNG_OK) {
+ goto end_notification_thread;
+ }
+
+ /* Return an updated trigger to the client. */
+ *return_trigger = trigger;
+
+end_notification_thread:
/* Ownership of trigger was transferred. */
trigger = NULL;
end:
}
}
- lttng_trigger_set_credentials(trigger, &cmd_creds);
+ /*
+ * Validate the trigger credentials against the command credentials.
+ * Only the root user can unregister a trigger with non-matching
+ * credentials.
+ */
+ if (!lttng_credentials_is_equal_uid(
+ lttng_trigger_get_credentials(trigger),
+ &cmd_creds)) {
+ if (lttng_credentials_get_uid(&cmd_creds) != 0) {
+ ERR("Trigger credentials do not match the command credentials");
+ ret = LTTNG_ERR_INVALID_TRIGGER;
+ goto end;
+ }
+ }
ret = notification_thread_command_unregister_trigger(notification_thread,
trigger);