Fix CVE-2017-14166:

https://github.com/libarchive/libarchive/issues/935
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-14166

Patch copied from upstream source repository:

https://github.com/libarchive/libarchive/commit/fa7438a0ff4033e4741c807394a9af6207940d71

From fa7438a0ff4033e4741c807394a9af6207940d71 Mon Sep 17 00:00:00 2001
From: Joerg Sonnenberger <joerg@bec.de>
Date: Tue, 5 Sep 2017 18:12:19 +0200
Subject: [PATCH] Do something sensible for empty strings to make fuzzers
 happy.

---
 libarchive/archive_read_support_format_xar.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/libarchive/archive_read_support_format_xar.c b/libarchive/archive_read_support_format_xar.c
index 7a22beb9d..93eeacc5e 100644
--- a/libarchive/archive_read_support_format_xar.c
+++ b/libarchive/archive_read_support_format_xar.c
@@ -1040,6 +1040,9 @@ atol10(const char *p, size_t char_cnt)
 	uint64_t l;
 	int digit;
 
+	if (char_cnt == 0)
+		return (0);
+
 	l = 0;
 	digit = *p - '0';
 	while (digit >= 0 && digit < 10  && char_cnt-- > 0) {
@@ -1054,7 +1057,10 @@ atol8(const char *p, size_t char_cnt)
 {
 	int64_t l;
 	int digit;
-        
+
+	if (char_cnt == 0)
+		return (0);
+
 	l = 0;
 	while (char_cnt-- > 0) {
 		if (*p >= '0' && *p <= '7')
?id=bd1bce0896150d7351d0c5553d197b0d628d8471'>tree</a><a href='/guix/commit/gnu/installer/timezone.scm?id=bd1bce0896150d7351d0c5553d197b0d628d8471'>commit</a><a href='/guix/diff/gnu/installer/timezone.scm?id=bd1bce0896150d7351d0c5553d197b0d628d8471'>diff</a></td><td class='form'><form class='right' method='get' action='/guix/log/gnu/installer/timezone.scm'>
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le='2020-08-02 15:54:37 +0300'>2020-08-02</span></td><td><a href='/guix/commit/tests/services/linux.scm?id=587e0d911dfff81647015e89847084b606e68f71'>services: Add zram-device-service.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/services/linux.scm (&lt;zram-device-configuration&gt;): New record.
(zram-device-service-type): New variable.
* doc/guix.texi (Linux Services): Document it.
* tests/services/linux.scm (zram-swap-device-test): New tests.
</span></span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2020-01-31 23:37:13 -0500'>2020-01-31</span></td><td><a href='/guix/commit/tests/services/linux.scm?id=d3e439e355284f136ff13eb3e6fffb4661552f3b'>gnu: Add earlyoom-service-type.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/services/linux.scm: New file.
* tests/services/linux.scm: Add test.
* Makefile.am (SCM_TESTS): Register test.
* doc/guix.texi (Linux Services): Add a new section and document the new
service and its configuration.
</span></span></td><td>Maxim Cournoyer</td></tr>