From: Jim Meyering <jim@meyering.net>
Date: Mon, 16 Apr 2012 15:20:02 +0000 (+0200)
Subject: diff: avoid stack-buffer-read-overrun for very long name
X-Git-Tag: v1.7.10.2~34^2~1
X-Git-Url: http://git.tremily.us/?a=commitdiff_plain;h=48e510b6a29b1066016cbbee75c0b196174a88d4;p=git.git

diff: avoid stack-buffer-read-overrun for very long name

Due to the use of strncpy without explicit NUL termination,
we could end up passing names n1 or n2 that are not NUL-terminated
to queue_diff, which requires NUL-terminated strings.
Ensure that each is NUL terminated.

Signed-off-by: Jim Meyering <meyering@redhat.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---

diff --git a/diff-no-index.c b/diff-no-index.c
index 3a3614468..5cd3ff584 100644
--- a/diff-no-index.c
+++ b/diff-no-index.c
@@ -109,6 +109,7 @@ static int queue_diff(struct diff_options *o,
 				n1 = buffer1;
 				strncpy(buffer1 + len1, p1.items[i1++].string,
 						PATH_MAX - len1);
+				buffer1[PATH_MAX-1] = 0;
 			}
 
 			if (comp < 0)
@@ -117,6 +118,7 @@ static int queue_diff(struct diff_options *o,
 				n2 = buffer2;
 				strncpy(buffer2 + len2, p2.items[i2++].string,
 						PATH_MAX - len2);
+				buffer2[PATH_MAX-1] = 0;
 			}
 
 			ret = queue_diff(o, n1, n2);