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);
lected'>koszko</option>
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<div class='path'>path: <a href='/guix/log/?id=737a3c12cd25f76e9fb4872e0a7a1ecb61aff131'>root</a>/<a href='/guix/log/README?id=737a3c12cd25f76e9fb4872e0a7a1ecb61aff131'>README</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/README?id=737a3c12cd25f76e9fb4872e0a7a1ecb61aff131&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2019-11-09 23:04:14 +0100'>2019-11-09</span></td><td><a href='/guix/commit/README?id=0758a70cc008171f31c848128deca9803536fe60'>doc: Mention value /var to localstatedir option.</a><span class='msg-avail'>...<span class='msg-tooltip'>* README (Installing Guix from Guix): Mention value /var to localstatedir option.
* doc/contributing.texi (Building from Git): Likewise.
* doc/guix.texi (Requirements): Likewise.

Signed-off-by: Ludovic Courtès &lt;ludo@gnu.org&gt;
</span></span></td><td>zimoun</td></tr>
<tr><td><span title='2019-09-04 23:41:07 +0200'>2019-09-04</span></td><td><a href='/guix/commit/README?id=f475c6e53e5b6912cc45663d50f1d03dadfb60b8'>doc: Update 'README'.</a><span class='msg-avail'>...<span class='msg-tooltip'>* README: Update intro a bit.
(Installing Guix as non-root): Remove as it's largely outdated.
(Contact): Update.
</span></span></td><td>Ludovic Courtès</td></tr>