From cf074a9b0e589bad8e6b210ac1e3a4714463f7db Mon Sep 17 00:00:00 2001
From: Phillip Wood <phillip.wood@dunelm.org.uk>
Date: Thu, 4 Oct 2018 11:07:42 +0100
Subject: [PATCH] diff --color-moved-ws: fix out of bounds string access

When adjusting the start of the string to take account of the change
in indentation the code was not checking that the string being
adjusted was in fact longer than the indentation change. This was
detected by asan.

Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk>
Reviewed-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 diff.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/diff.c b/diff.c
index 566419dc75..6f12212134 100644
--- a/diff.c
+++ b/diff.c
@@ -865,7 +865,7 @@ static int cmp_in_block_with_wsd(const struct diff_options *o,
 		al -= wslen;
 	}
 
-	if (strcmp(a, c))
+	if (al != cl || memcmp(a, c, al))
 		return 1;
 
 	return 0;