From 2b4809406b6536cbb67a2282bf855710b8454dc2 Mon Sep 17 00:00:00 2001
From: Werner Koch <wk@gnupg.org>
Date: Mon, 24 Nov 2014 19:38:04 +0100
Subject: [PATCH] gpg: Fix off-by-one read in the attribute subpacket parser.
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* g10/parse-packet.c (parse_attribute_subpkts): Check that the
attribute packet is large enough for the subpacket type.
--

Reported-by: Hanno Böck
Signed-off-by: Werner Koch <wk@gnupg.org>

(backported from commit 0988764397f99db4efef1eabcdb8072d6159af76)
---
 g10/parse-packet.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/g10/parse-packet.c b/g10/parse-packet.c
index dcda8ef59..db1702f88 100644
--- a/g10/parse-packet.c
+++ b/g10/parse-packet.c
@@ -2026,6 +2026,14 @@ parse_attribute_subpkts(PKT_user_id *uid)
       if( buflen < n )
 	goto too_short;
 
+      if (!n)
+        {
+          /* Too short to encode the subpacket type.  */
+          if (opt.verbose)
+            log_info ("attribute subpacket too short\n");
+          break;
+        }
+
       attribs=xrealloc(attribs,(count+1)*sizeof(struct user_attribute));
       memset(&attribs[count],0,sizeof(struct user_attribute));