diff --git a/dix/dispatch.c b/dix/dispatch.c
index c651c3d88..92be773e6 100644
--- a/dix/dispatch.c
+++ b/dix/dispatch.c
@@ -3766,14 +3766,11 @@ int
 ProcEstablishConnection(ClientPtr client)
 {
     const char *reason;
-    char *auth_proto, *auth_string;
     xConnClientPrefix *prefix;
 
     REQUEST(xReq);
 
     prefix = (xConnClientPrefix *) ((char *) stuff + sz_xReq);
-    auth_proto = (char *) prefix + sz_xConnClientPrefix;
-    auth_string = auth_proto + pad_to_int32(prefix->nbytesAuthProto);
 
     if ((client->req_len << 2) != sz_xReq + sz_xConnClientPrefix +
             pad_to_int32(prefix->nbytesAuthProto) +
@@ -3782,12 +3779,15 @@ ProcEstablishConnection(ClientPtr client)
     else if ((prefix->majorVersion != X_PROTOCOL) ||
         (prefix->minorVersion != X_PROTOCOL_REVISION))
         reason = "Protocol version mismatch";
-    else
+    else {
+        char *auth_proto = (char *) prefix + sz_xConnClientPrefix;
+        char *auth_string = auth_proto + pad_to_int32(prefix->nbytesAuthProto);
         reason = ClientAuthorized(client,
                                   (unsigned short) prefix->nbytesAuthProto,
                                   auth_proto,
                                   (unsigned short) prefix->nbytesAuthString,
                                   auth_string);
+    }
 
     return (SendConnSetup(client, reason));
 }