Fix CVE-2018-1000097:

https://security-tracker.debian.org/tracker/CVE-2018-1000097
https://nvd.nist.gov/vuln/detail/CVE-2018-1000097

Patch taken from upstream bug report:
https://lists.gnu.org/archive/html/bug-gnu-utils/2018-02/msg00005.html

diff --git a/src/unshar.c b/src/unshar.c
index 80bc3a9..0fc3773 100644
--- a/src/unshar.c
+++ b/src/unshar.c
@@ -240,7 +240,7 @@ find_archive (char const * name, FILE * file, off_t start)
       off_t position = ftello (file);
 
       /* Read next line, fail if no more and no previous process.  */
-      if (!fgets (rw_buffer, BUFSIZ, file))
+      if (!fgets (rw_buffer, rw_base_size, file))
 	{
 	  if (!start)
 	    error (0, 0, _("Found no shell commands in %s"), name);
='koszko' selected='selected'>koszko</option>
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<div class='path'>path: <a href='/guix/log/?id=548d0ddd7fbf91c860b5061d4f6ac58ed249ec5d'>root</a>/<a href='/guix/log/tests?id=548d0ddd7fbf91c860b5061d4f6ac58ed249ec5d'>tests</a>/<a href='/guix/log/tests/ed25519.key?id=548d0ddd7fbf91c860b5061d4f6ac58ed249ec5d'>ed25519.key</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/tests/ed25519.key?id=548d0ddd7fbf91c860b5061d4f6ac58ed249ec5d&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2020-05-04 09:56:12 +0200'>2020-05-04</span></td><td><a href='/guix/commit/tests/ed25519.key?id=43408e304ffb1149f35cb539b40d673d567c9116'>Add (guix openpgp).</a><span class='msg-avail'>...<span class='msg-tooltip'>* guix/openpgp.scm, tests/openpgp.scm, tests/civodul.key,
tests/dsa.key, tests/ed25519.key, tests/rsa.key,
tests/ed25519.sec: New files.
* Makefile.am (MODULES): Add guix/openpgp.scm.
(SCM_TESTS): Add tests/openpgp.scm.
(EXTRA_DIST): Add tests/*.key and tests/ed25519.sec.
</span></span></td><td>Ludovic Courtès</td></tr>
<span title='2019-09-23 10:41:30 +0200'>2019-09-23</span></td><td><a href='/guix/commit/.guix-channel?id=dcc90d15581189dbc30e201db2b807273d6484f0'>Add '.guix-channel' file.</a><span class='msg-avail'>...<span class='msg-tooltip'>* .guix-channel: New file.
* Makefile.am (EXTRA_DIST): Add it.
</span></span></td><td>Ludovic Courtès</td></tr>