CVE-2015-5370: s4:librpc/rpc: make use of dcerpc_map_ack_reason() in dcerpc_bind_recv...

This should give better error messages if the server doesn't support
a specific abstract/transfer syntax.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=11344

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Günther Deschner <gd@samba.org>

diff --git a/source4/librpc/rpc/dcerpc.c b/source4/librpc/rpc/dcerpc.c
index bd9c59d8a8584ec9da8c1dab82e596038943676b..c799eabcf7ad59e7b381f004853cf4b494b43c2e 100644 (file)
--- a/source4/librpc/rpc/dcerpc.c
+++ b/source4/librpc/rpc/dcerpc.c
@@ -1343,13 +1343,21 @@ static void dcerpc_bind_recv_handler(struct rpc_request *subreq,
        }
 
        if ((pkt->ptype != DCERPC_PKT_BIND_ACK) ||
-           (pkt->u.bind_ack.num_results == 0) ||
-           (pkt->u.bind_ack.ctx_list[0].result != 0)) {
+           (pkt->u.bind_ack.num_results == 0)) {
                state->p->last_fault_code = DCERPC_NCA_S_PROTO_ERROR;
                tevent_req_nterror(req, NT_STATUS_NET_WRITE_FAULT);
                return;
        }
 
+       if (pkt->u.bind_ack.ctx_list[0].result != 0) {
+               status = dcerpc_map_ack_reason(&pkt->u.bind_ack.ctx_list[0]);
+               DEBUG(2,("dcerpc: bind_ack failed - reason %d - %s\n",
+                        pkt->u.bind_ack.ctx_list[0].reason.value,
+                        nt_errstr(status)));
+               tevent_req_nterror(req, status);
+               return;
+       }
+
        /*
         * DCE-RPC 1.1 (c706) specifies
         * CONST_MUST_RCV_FRAG_SIZE as 1432