From 4118b13c0c191e3d5dcd5c73e37b19b49c5381e1 Mon Sep 17 00:00:00 2001
From: Adam Langley <agl@imperialviolet.org>
Date: Fri, 6 Jun 2014 14:44:20 -0700
Subject: [PATCH 05/16] Fix return code for truncated DTLS fragment.
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Previously, a truncated DTLS fragment in
|dtls1_process_out_of_seq_message| would cause *ok to be cleared, but
the return value would still be the number of bytes read. This would
cause |dtls1_get_message| not to consider it an error and it would
continue processing as normal until the calling function noticed that
*ok was zero.

I can't see an exploit here because |dtls1_get_message| uses
|s->init_num| as the length, which will always be zero from what I can
see.

Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Emilia Käsper <emilia@openssl.org>
---
 ssl/d1_both.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/ssl/d1_both.c b/ssl/d1_both.c
index bb52d92..ac0fcaa 100644
--- a/ssl/d1_both.c
+++ b/ssl/d1_both.c
@@ -771,7 +771,9 @@ dtls1_process_out_of_seq_message(SSL *s, struct hm_header_st* msg_hdr, int *ok)
 			/* read the body of the fragment (header has already been read */
 			i = s->method->ssl_read_bytes(s,SSL3_RT_HANDSHAKE,
 				frag->fragment,frag_len,0);
-			if (i<=0 || (unsigned long)i!=frag_len)
+			if ((unsigned long)i!=frag_len)
+				i = -1;
+			if (i<=0)
 				goto err;
 			}
 
-- 
2.0.1