Fix from 1.0.0-stable branch.

1 files changed, 10 insertions, 1 deletions

diff --git a/ssl/d1_both.c b/ssl/d1_both.c
index 5727c73776..63d00062f2 100644
--- a/ssl/d1_both.c
+++ b/ssl/d1_both.c
@@ -561,7 +561,16 @@ dtls1_process_out_of_seq_message(SSL *s, struct hm_header_st* msg_hdr, int *ok)
 	if ((msg_hdr->frag_off+frag_len) > msg_hdr->msg_len)
 		goto err;
 
-	if (msg_hdr->seq <= s->d1->handshake_read_seq)
+	/* Try to find item in queue, to prevent duplicate entries */
+	memset(seq64be,0,sizeof(seq64be));
+	seq64be[6] = (unsigned char) (msg_hdr->seq>>8);
+	seq64be[7] = (unsigned char) msg_hdr->seq;
+	item = pqueue_find(s->d1->buffered_messages, seq64be);
+	
+	/* Discard the message if sequence number was already there, is
+	 * too far in the future or the fragment is already in the queue */
+	if (msg_hdr->seq <= s->d1->handshake_read_seq ||
+		msg_hdr->seq > s->d1->handshake_read_seq + 10 || item != NULL)
 		{
 		unsigned char devnull [256];