From: Tim Kientzle <kientzle@gmail.com>
Date: Fri, 26 Sep 2014 01:51:57 +0000 (-0700)
Subject: Issue 378: compute string pointers after concatenation, to protect against reallocati... 
X-Git-Tag: v3.1.900a~200
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c1732828cd802c26e18891c4c95f49c15819c985;p=thirdparty%2Flibarchive.git

Issue 378: compute string pointers after concatenation, to protect against reallocation moving the string
---

diff --git a/libarchive/archive_util.c b/libarchive/archive_util.c
index 1b685d109..3a951c819 100644
--- a/libarchive/archive_util.c
+++ b/libarchive/archive_util.c
@@ -330,10 +330,11 @@ __archive_mktemp(const char *tmpdir)
 	/*
 	 * Create a temporary file.
 	 */
+	const wchar_t *suffix = L"XXXXXXXXXX";
 	archive_wstrcat(&temp_name, L"libarchive_");
-	xp = temp_name.s + archive_strlen(&temp_name);
-	archive_wstrcat(&temp_name, L"XXXXXXXXXX");
+	archive_wstrcat(&temp_name, suffix);
 	ep = temp_name.s + archive_strlen(&temp_name);
+	xp = ep - wcslen(suffix);
 
 	if (!CryptAcquireContext(&hProv, NULL, NULL, PROV_RSA_FULL,
 		CRYPT_VERIFYCONTEXT)) {