Fix: illegal memory access in viewer_list_sessions

[lttng-tools.git] / src / bin / lttng-relayd / live.c

diff --git a/src/bin/lttng-relayd/live.c b/src/bin/lttng-relayd/live.c
index 0cf2665161251a71ce1351e76c5f997598c5251d..f87e4baf0846ad9b666ac78ceb98cec6b4635247 100644 (file)
--- a/src/bin/lttng-relayd/live.c
+++ b/src/bin/lttng-relayd/live.c
@@ -831,10 +831,19 @@ int viewer_list_sessions(struct relay_connection *conn)
                        buf_count = new_buf_count;
                }
                send_session = &send_session_buf[count];
-               strncpy(send_session->session_name, session->session_name,
-                               sizeof(send_session->session_name));
-               strncpy(send_session->hostname, session->hostname,
-                               sizeof(send_session->hostname));
+               if (lttng_strncpy(send_session->session_name,
+                               session->session_name,
+                               sizeof(send_session->session_name))) {
+                       ret = -1;
+                       rcu_read_unlock();
+                       goto end_free;
+               }
+               if (lttng_strncpy(send_session->hostname, session->hostname,
+                               sizeof(send_session->hostname))) {
+                       ret = -1;
+                       rcu_read_unlock();
+                       goto end_free;
+               }
                send_session->id = htobe64(session->id);
                send_session->live_timer = htobe32(session->live_timer);
                if (session->viewer_attached) {
@@ -1734,6 +1743,78 @@ end:
        return ret;
 }
 
+/*
+ * Detach a viewer session.
+ *
+ * Return 0 on success or else a negative value.
+ */
+static
+int viewer_detach_session(struct relay_connection *conn)
+{
+       int ret;
+       struct lttng_viewer_detach_session_response response;
+       struct lttng_viewer_detach_session_request request;
+       struct relay_session *session = NULL;
+       uint64_t viewer_session_to_close;
+
+       DBG("Viewer detach session received");
+
+       assert(conn);
+
+       health_code_update();
+
+       /* Receive the request from the connected client. */
+       ret = recv_request(conn->sock, &request, sizeof(request));
+       if (ret < 0) {
+               goto end;
+       }
+       viewer_session_to_close = be64toh(request.session_id);
+
+       if (!conn->viewer_session) {
+               DBG("Client trying to detach before creating a live viewer session");
+               response.status = htobe32(LTTNG_VIEWER_DETACH_SESSION_ERR);
+               goto send_reply;
+       }
+
+       health_code_update();
+
+       memset(&response, 0, sizeof(response));
+       DBG("Detaching from session ID %" PRIu64, viewer_session_to_close);
+
+       session = session_get_by_id(be64toh(request.session_id));
+       if (!session) {
+               DBG("Relay session %" PRIu64 " not found",
+                               be64toh(request.session_id));
+               response.status = htobe32(LTTNG_VIEWER_DETACH_SESSION_UNK);
+               goto send_reply;
+       }
+
+       ret = viewer_session_is_attached(conn->viewer_session, session);
+       if (ret != 1) {
+               DBG("Not attached to this session");
+               response.status = htobe32(LTTNG_VIEWER_DETACH_SESSION_ERR);
+               goto send_reply_put;
+       }
+
+       viewer_session_close_one_session(conn->viewer_session, session);
+       response.status = htobe32(LTTNG_VIEWER_DETACH_SESSION_OK);
+       DBG("Session %" PRIu64 " detached.", viewer_session_to_close);
+
+send_reply_put:
+       session_put(session);
+
+send_reply:
+       health_code_update();
+       ret = send_response(conn->sock, &response, sizeof(response));
+       if (ret < 0) {
+               goto end;
+       }
+       health_code_update();
+       ret = 0;
+
+end:
+       return ret;
+}
 
 /*
  * live_relay_unknown_command: send -1 if received unknown command
@@ -1795,6 +1876,9 @@ int process_control(struct lttng_viewer_cmd *recv_hdr,
        case LTTNG_VIEWER_CREATE_SESSION:
                ret = viewer_create_session(conn);
                break;
+       case LTTNG_VIEWER_DETACH_SESSION:
+               ret = viewer_detach_session(conn);
+               break;
        default:
                ERR("Received unknown viewer command (%u)",
                                be32toh(recv_hdr->cmd));