upstream url: https://code.9front.org/hg/drawterm/rev/fbf56ef73faf

diff -upr drawterm-20170119.orig/kern/devmouse.c drawterm-20170119/kern/devmouse.c
--- drawterm-20170119.orig/kern/devmouse.c	2017-01-30 09:18:21.250082979 +0100
+++ drawterm-20170119/kern/devmouse.c	2017-01-30 09:18:40.093373597 +0100
@@ -122,7 +122,7 @@ mouseclose(Chan *c)
 long
 mouseread(Chan *c, void *va, long n, vlong offset)
 {
-	char buf[4*12+1];
+	char buf[1+4*12+1];
 	Mousestate m;
 	uchar *p;
 	int b;