Change behavior on missing/present event to warn instead of asserting. (457d38a6) · Commits · k3rn3l_kr4z3_ / The-Onion-Router

changes/bug16248

0 → 100644

+8 −0

Original line number	Diff line number	Diff line
		o Major bugfixes (dns proxy mode, crash):
		- Avoid crashing when running as a DNS proxy. Closes bug 16248; bugfix on
		0.2.0.1-alpha. Patch from 'cypherpunks'.

		o Minor features (bug-resistance):
		- Make Tor survive errors involving connections without a corresponding
		event object. Previously we'd fail with an assertion; now we produce a
		log message. Related to bug 16248.

src/or/main.c

+37 −12

Original line number	Diff line number	Diff line
		@@ -506,6 +506,35 @@ connection_is_reading(connection_t *conn)
		(conn->read_event && event_pending(conn->read_event, EV_READ, NULL));
		}

		static int
		connection_check_event(connection_t conn, struct event ev)
		{
		int bad;

		if (conn->type == CONN_TYPE_AP && TO_EDGE_CONN(conn)->is_dns_request) {
		bad = ev != NULL;
		} else {
		bad = ev == NULL;
		}

		if (bad) {
		log_warn(LD_BUG, "Event missing on connection %p [%s;%s]. "
		"socket=%d. linked=%d. "
		"is_dns_request=%d. Marked_for_close=%s:%d",
		conn,
		conn_type_to_string(conn->type),
		conn_state_to_string(conn->type, conn->state),
		(int)conn->s, (int)conn->linked,
		(conn->type == CONN_TYPE_AP && TO_EDGE_CONN(conn)->is_dns_request),
		conn->marked_for_close_file ? conn->marked_for_close_file : "-",
		conn->marked_for_close
		);
		log_backtrace(LOG_WARN, LD_BUG, "Backtrace attached.");
		return -1;
		}
		return 0;
		}

		/** Tell the main loop to stop notifying <b>conn</b> of any read events. */
		void
		connection_stop_reading(connection_t *conn)
		@@ -517,14 +546,10 @@ connection_stop_reading(connection_t *conn)
		return;
		});

		/* if dummy conn then no socket and no event, nothing to do here */
		if (conn->type == CONN_TYPE_AP && TO_EDGE_CONN(conn)->is_dns_request) {
		tor_assert(!conn->read_event);
		if (connection_check_event(conn, conn->read_event) < 0) {
		return;
		}

		tor_assert(conn->read_event);

		if (conn->linked) {
		conn->reading_from_linked_conn = 0;
		connection_stop_reading_from_linked_conn(conn);
		@@ -548,14 +573,10 @@ connection_start_reading(connection_t *conn)
		return;
		});

		/* if dummy conn then no socket and no event, nothing to do here */
		if (conn->type == CONN_TYPE_AP && TO_EDGE_CONN(conn)->is_dns_request) {
		tor_assert(!conn->read_event);
		if (connection_check_event(conn, conn->read_event) < 0) {
		return;
		}

		tor_assert(conn->read_event);

		if (conn->linked) {
		conn->reading_from_linked_conn = 1;
		if (connection_should_read_from_linked_conn(conn))
		@@ -594,7 +615,9 @@ connection_stop_writing(connection_t *conn)
		return;
		});

		tor_assert(conn->write_event);
		if (connection_check_event(conn, conn->write_event) < 0) {
		return;
		}

		if (conn->linked) {
		conn->writing_to_linked_conn = 0;
		@@ -620,7 +643,9 @@ connection_start_writing(connection_t *conn)
		return;
		});

		tor_assert(conn->write_event);
		if (connection_check_event(conn, conn->write_event) < 0) {
		return;
		}

		if (conn->linked) {
		conn->writing_to_linked_conn = 1;