===================================================================
RCS file: /cvsrepo/anoncvs/cvs/src/usr.bin/tmux/screen-write.c,v
retrieving revision 1.222
retrieving revision 1.222.2.1
diff -u -r1.222 -r1.222.2.1
--- src/usr.bin/tmux/screen-write.c	2023/09/15 15:49:05	1.222
+++ src/usr.bin/tmux/screen-write.c	2023/11/20 18:08:24	1.222.2.1
@@ -1,4 +1,4 @@
-/* $OpenBSD: screen-write.c,v 1.222 2023/09/15 15:49:05 nicm Exp $ */
+/* $OpenBSD: screen-write.c,v 1.222.2.1 2023/11/20 18:08:24 bluhm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -2024,6 +2024,10 @@
 		} else if (!utf8_has_zwj(&last.data))
 			return (0);
 	}
+
+	/* Check if this combined character would be too long. */
+	if (last.data.size + ud->size > sizeof last.data.data)
+		return (0);
 
 	/* Combining; flush any pending output. */
 	screen_write_collect_flush(ctx, 0, __func__);