Fix CVE-2017-14502:

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-14502
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=573

Patch copied from upstream source repository:

https://github.com/libarchive/libarchive/commit/5562545b5562f6d12a4ef991fae158bf4ccf92b6

From 5562545b5562f6d12a4ef991fae158bf4ccf92b6 Mon Sep 17 00:00:00 2001
From: Joerg Sonnenberger <joerg@bec.de>
Date: Sat, 9 Sep 2017 17:47:32 +0200
Subject: [PATCH] Avoid a read off-by-one error for UTF16 names in RAR
 archives.

Reported-By: OSS-Fuzz issue 573
---
 libarchive/archive_read_support_format_rar.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/libarchive/archive_read_support_format_rar.c b/libarchive/archive_read_support_format_rar.c
index cbb14c32..751de697 100644
--- a/libarchive/archive_read_support_format_rar.c
+++ b/libarchive/archive_read_support_format_rar.c
@@ -1496,7 +1496,11 @@ read_header(struct archive_read *a, struct archive_entry *entry,
         return (ARCHIVE_FATAL);
       }
       filename[filename_size++] = '\0';
-      filename[filename_size++] = '\0';
+      /*
+       * Do not increment filename_size here as the computations below
+       * add the space for the terminating NUL explicitly.
+       */
+      filename[filename_size] = '\0';
 
       /* Decoded unicode form is UTF-16BE, so we have to update a string
        * conversion object for it. */
-- 
2.15.1

