Follow on from CVE-2014-3571. This fixes the code that was the original source

of the crash due to p being NULL. Steve's fix prevents this situation from
occuring - however this is by no means obvious by looking at the code for
dtls1_get_record. This fix just makes things look a bit more sane.

Reviewed-by: Dr Stephen Henson <steve@openssl.org>

diff --git a/ssl/d1_pkt.c b/ssl/d1_pkt.c
index b76703a5e0542172f0620d732a2729e7f2600689..2851add08a94c1ad695fac459c058bd5014da0bc 100644 (file)
--- a/ssl/d1_pkt.c
+++ b/ssl/d1_pkt.c
@@ -679,7 +679,8 @@ again:
                 * would be dropped unnecessarily.
                 */
                if (!(s->d1->listen && rr->type == SSL3_RT_HANDSHAKE &&
-                   *p == SSL3_MT_CLIENT_HELLO) &&
+                   s->packet_length > DTLS1_RT_HEADER_LENGTH &&
+                   s->packet[DTLS1_RT_HEADER_LENGTH] == SSL3_MT_CLIENT_HELLO) &&
                    !dtls1_record_replay_check(s, bitmap))
                        {
                        rr->length = 0;