From: Toni Wilen <twilen@winuae.net>
Date: Sun, 14 Dec 2025 11:00:04 +0000 (+0200)
Subject: Fix genlock buffer overflow
X-Git-Tag: 6020~8
X-Git-Url: https://git.unchartedbackwaters.co.uk/w/?a=commitdiff_plain;h=14d61c8a5b4ab001d270a5650c77607d8408dd9a;p=francis%2Fwinuae.git

Fix genlock buffer overflow
---

diff --git a/drawing.cpp b/drawing.cpp
index e6729997..47596273 100644
--- a/drawing.cpp
+++ b/drawing.cpp
@@ -7074,8 +7074,7 @@ void draw_denise_border_line_fast(int gfx_ypos, bool blank, enum nln_how how, st
 			draw_blank_end();
 		}
 
-		total = end - start;
-		if (need_genlock_data && gbuf && total) {
+		if (need_genlock_data && gbuf && total > 0) {
 			int max = addrdiff(xlinebuffer_genlock_end, gbufp);
 			total += GENLOCK_EXTRA_CLEAR;
 			if (total > max) {