diff --git a/fileio.c b/fileio.c
index ba0a1d0..03fc4be 100644
--- a/fileio.c
+++ b/fileio.c
@@ -2006,6 +2006,7 @@ int do_string(__G__ length, option)   /* return PK-type error code */
     unsigned comment_bytes_left;
     unsigned int block_len;
     int error=PK_OK;
+    unsigned int length2;
 #ifdef AMIGA
     char tmp_fnote[2 * AMIGA_FILENOTELEN];   /* extra room for squozen chars */
 #endif
@@ -2292,8 +2293,12 @@ int do_string(__G__ length, option)   /* return PK-type error code */
             seek_zipf(__G__ G.cur_zipfile_bufstart - G.extra_bytes +
                       (G.inptr-G.inbuf) + length);
         } else {
-            if (readbuf(__G__ (char *)G.extra_field, length) == 0)
+            if ((length2 = readbuf(__G__ (char *)G.extra_field, length)) == 0)
                 return PK_EOF;
+            if(length2 < length) {
+              memset (__G__ (char *)G.extra_field+length2, 0 , length-length2);
+              length = length2;
+            }
             /* Looks like here is where extra fields are read */
             getZip64Data(__G__ G.extra_field, length);
 #ifdef UNICODE_SUPPORT
fs/?id=e89763682ee5b0ba9c770c53a29832e96b76b1ee'>refs</a><a class='active' href='/guix/log/gnu/tests/cachefilesd.scm'>log</a><a href='/guix/tree/gnu/tests/cachefilesd.scm?id=e89763682ee5b0ba9c770c53a29832e96b76b1ee'>tree</a><a href='/guix/commit/gnu/tests/cachefilesd.scm?id=e89763682ee5b0ba9c770c53a29832e96b76b1ee'>commit</a><a href='/guix/diff/gnu/tests/cachefilesd.scm?id=e89763682ee5b0ba9c770c53a29832e96b76b1ee'>diff</a></td><td class='form'><form class='right' method='get' action='/guix/log/gnu/tests/cachefilesd.scm'>
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<div class='path'>path: <a href='/guix/log/?id=e89763682ee5b0ba9c770c53a29832e96b76b1ee'>root</a>/<a href='/guix/log/gnu?id=e89763682ee5b0ba9c770c53a29832e96b76b1ee'>gnu</a>/<a href='/guix/log/gnu/tests?id=e89763682ee5b0ba9c770c53a29832e96b76b1ee'>tests</a>/<a href='/guix/log/gnu/tests/cachefilesd.scm?id=e89763682ee5b0ba9c770c53a29832e96b76b1ee'>cachefilesd.scm</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/tests/cachefilesd.scm?id=e89763682ee5b0ba9c770c53a29832e96b76b1ee&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2023-08-15 23:30:44 +0200'>2023-08-15</span></td><td><a href='/guix/commit/gnu/tests/cachefilesd.scm?id=b8ee6b8a59bf02f47a6668e016905308b441523e'>services: Add cachefilesd service.</a><span class='msg-avail'>...<span class='msg-tooltip'>Thanks to Bruno Victal "mirai" for cooperating on this patch and for
generously sharing a wealth of insights about Guix services.

Thanks to Jean-Baptiste Note for an early version of this service!

* doc/guix.texi (Linux Services)[Cachefilesd Service]: New heading.
* gnu/services/linux.scm (serialize-string, non-negative-integer?)
(serialize-non-negative-integer, string, non-negative-integer)
(make-option-serializer, make-percentage-threshold-serializer): New
procedures.
(cachefilesd-configuration): New record type.
(cachefilesd-service-type): New variable.
* gnu/tests/cachefilesd.scm: New file.
* gnu/local.mk (GNU_SYSTEM_MODULES): Add it.

Co-authored-by: Bruno Victal &lt;mirai@makinata.eu&gt;
Signed-off-by: Ludovic Courtès &lt;ludo@gnu.org&gt;
</span></span></td><td>Felix Lechner</td></tr>