Copied from Debian.

From: Petr Stodulka <pstodulk@redhat.com>
Date: Mon, 14 Sep 2015 18:23:17 +0200
Subject: Upstream fix for heap overflow
Bug-Debian: https://bugs.debian.org/802162
Bug-RedHat: https://bugzilla.redhat.com/show_bug.cgi?id=1260944
Origin: https://bugzilla.redhat.com/attachment.cgi?id=1073002
Forwarded: yes

---
 crypt.c | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

--- a/crypt.c
+++ b/crypt.c
@@ -465,7 +465,17 @@
     GLOBAL(pInfo->encrypted) = FALSE;
     defer_leftover_input(__G);
     for (n = 0; n < RAND_HEAD_LEN; n++) {
-        b = NEXTBYTE;
+        /* 2012-11-23 SMS.  (OUSPG report.)
+         * Quit early if compressed size < HEAD_LEN.  The resulting
+         * error message ("unable to get password") could be improved,
+         * but it's better than trying to read nonexistent data, and
+         * then continuing with a negative G.csize.  (See
+         * fileio.c:readbyte()).
+         */
+        if ((b = NEXTBYTE) == (ush)EOF)
+        {
+            return PK_ERR;
+        }
         h[n] = (uch)b;
         Trace((stdout, " (%02x)", h[n]));
     }
href='/guix/'>summary</a><a href='/guix/refs/?id=b35bd82a80b20ce4061a007e1ef8035c3be27879'>refs</a><a class='active' href='/guix/log/gnu/packages/aux-files/linux-libre/4.19-i686.conf'>log</a><a href='/guix/tree/gnu/packages/aux-files/linux-libre/4.19-i686.conf?id=b35bd82a80b20ce4061a007e1ef8035c3be27879'>tree</a><a href='/guix/commit/gnu/packages/aux-files/linux-libre/4.19-i686.conf?id=b35bd82a80b20ce4061a007e1ef8035c3be27879'>commit</a><a href='/guix/diff/gnu/packages/aux-files/linux-libre/4.19-i686.conf?id=b35bd82a80b20ce4061a007e1ef8035c3be27879'>diff</a></td><td class='form'><form class='right' method='get' action='/guix/log/gnu/packages/aux-files/linux-libre/4.19-i686.conf'>
<input type='hidden' name='id' value='b35bd82a80b20ce4061a007e1ef8035c3be27879'/><select name='qt'>
<option value='grep'>log msg</option>
<option value='author'>author</option>
<option value='committer'>committer</option>
<option value='range'>range</option>
</select>
<input class='txt' type='search' size='10' name='q' value=''/>
<input type='submit' value='search'/>
</form>
</td></tr></table>
<div class='path'>path: <a href='/guix/log/?id=b35bd82a80b20ce4061a007e1ef8035c3be27879'>root</a>/<a href='/guix/log/gnu?id=b35bd82a80b20ce4061a007e1ef8035c3be27879'>gnu</a>/<a href='/guix/log/gnu/packages?id=b35bd82a80b20ce4061a007e1ef8035c3be27879'>packages</a>/<a href='/guix/log/gnu/packages/aux-files?id=b35bd82a80b20ce4061a007e1ef8035c3be27879'>aux-files</a>/<a href='/guix/log/gnu/packages/aux-files/linux-libre?id=b35bd82a80b20ce4061a007e1ef8035c3be27879'>linux-libre</a>/<a href='/guix/log/gnu/packages/aux-files/linux-libre/4.19-i686.conf?id=b35bd82a80b20ce4061a007e1ef8035c3be27879'>4.19-i686.conf</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/gnu/packages/aux-files/linux-libre/4.19-i686.conf?id=b35bd82a80b20ce4061a007e1ef8035c3be27879&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2023-02-19 01:00:01 +0100'>2023-02-19</span></td><td><a href='/guix/commit/gnu/packages/aux-files/linux-libre/4.19-i686.conf?id=e701f67246680c81dd111cf7136b936bf7d8718b'>gnu: linux-libre: Consistently provide the drop_monitor module.</a><span class='msg-avail'>...</span></td><td>Tobias Geerinckx-Rice</td></tr>