===================================================================
RCS file: /cvsrepo/anoncvs/cvs/src/usr.bin/tmux/window-copy.c,v
retrieving revision 1.198
retrieving revision 1.199
diff -u -r1.198 -r1.199
--- src/usr.bin/tmux/window-copy.c	2018/09/03 08:47:27	1.198
+++ src/usr.bin/tmux/window-copy.c	2018/09/03 08:51:43	1.199
@@ -1,4 +1,4 @@
-/* $OpenBSD: window-copy.c,v 1.198 2018/09/03 08:47:27 nicm Exp $ */
+/* $OpenBSD: window-copy.c,v 1.199 2018/09/03 08:51:43 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -1273,11 +1273,13 @@
 {
 	struct window_copy_mode_data	*data = wp->modedata;
 	const char			*errstr;
-	u_int				 lineno;
+	int				 lineno;
 
-	lineno = strtonum(linestr, 0, screen_hsize(data->backing), &errstr);
+	lineno = strtonum(linestr, -1, INT_MAX, &errstr);
 	if (errstr != NULL)
 		return;
+	if (lineno < 0 || (u_int)lineno > screen_hsize(data->backing))
+		lineno = screen_hsize(data->backing);
 
 	data->oy = lineno;
 	window_copy_update_selection(wp, 1);