From 210e402acd3e284b32db1901e43bf1470e659e49 Mon Sep 17 00:00:00 2001
From: Werner Koch <wk@gnupg.org>
Date: Fri, 8 Jun 2018 10:45:21 +0200
Subject: [PATCH] gpg: Sanitize diagnostic with the original file name.

* g10/mainproc.c (proc_plaintext): Sanitize verbose output.
--

This fixes a forgotten sanitation of user supplied data in a verbose
mode diagnostic.  The mention CVE is about using this to inject
status-fd lines into the stderr output.  Other harm good as well be
done.  Note that GPGME based applications are not affected because
GPGME does not fold status output into stderr.

CVE-id: CVE-2018-12020
GnuPG-bug-id: 4012
(cherry picked from commit 13f135c7a252cc46cff96e75968d92b6dc8dce1b)
---
 g10/mainproc.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/g10/mainproc.c b/g10/mainproc.c
index 116b72a6b..72b0dd828 100644
--- a/g10/mainproc.c
+++ b/g10/mainproc.c
@@ -758,7 +758,14 @@ proc_plaintext( CTX c, PACKET *pkt )
   if (pt->namelen == 8 && !memcmp( pt->name, "_CONSOLE", 8))
     log_info (_("Note: sender requested \"for-your-eyes-only\"\n"));
   else if (opt.verbose)
-    log_info (_("original file name='%.*s'\n"), pt->namelen, pt->name);
+    {
+      /* We don't use print_utf8_buffer because that would require a
+       * string change which we don't want in 2.2.  It is also not
+       * clear whether the filename is always utf-8 encoded.  */
+      char *tmp = make_printable_string (pt->name, pt->namelen, 0);
+      log_info (_("original file name='%.*s'\n"), (int)strlen (tmp), tmp);
+      xfree (tmp);
+    }
 
   free_md_filter_context (&c->mfx);
   if (gcry_md_open (&c->mfx.md, 0, 0))
-- 
2.17.1