From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BDA66C433E0 for ; Sat, 30 May 2020 15:51:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 94BB72074D for ; Sat, 30 May 2020 15:51:44 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="LFauSk/m" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729063AbgE3Pvn (ORCPT ); Sat, 30 May 2020 11:51:43 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:49037 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728927AbgE3Pvn (ORCPT ); Sat, 30 May 2020 11:51:43 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1590853901; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=T0Lu+lmTMR1GonhEKL4kTfNnILEmWnuXbiCGc9IKu1o=; b=LFauSk/mGGIKfvRZhRds2XYApu14k0s486X7amORZidpJ68YMyNIm52dxW9VI5AGQew4gY Kw1wMBjym5B0D9B0C9dv0P/ZwOVkWCW55j56U4qXL88uOK31sLUOxc5yHNuxSUIL+z2hk7 j9/QKuiJT2cdF8EiRuK9hi9Af1b7hzI= Received: from mail-wm1-f72.google.com (mail-wm1-f72.google.com [209.85.128.72]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-427-mPGdDA2FMOO5Sgatl7T6VQ-1; Sat, 30 May 2020 11:51:40 -0400 X-MC-Unique: mPGdDA2FMOO5Sgatl7T6VQ-1 Received: by mail-wm1-f72.google.com with SMTP id s15so1625729wmc.8 for ; Sat, 30 May 2020 08:51:39 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=T0Lu+lmTMR1GonhEKL4kTfNnILEmWnuXbiCGc9IKu1o=; b=rSZp2QH1FNpdQHZtK+lwiWDRQHeyUm0wYIeG234MXeszCEanCGPHPLnmdtWu/p+LZZ bSYhWNwmPMLJaD3oiUH3ytL/YUFiHiwZ7zaQcu4RFMjg565NCZAcFdsZMXwuQ4UU2+lo 0Bo2+8t+U+RdRha5aqVzg30Q+l259F2KqN8eTxRDq47KtnArQ33mXdCG0uX1+CzK9aC9 I0Dv6v9/AXd3TT2N2buzNkeIzZNXfg6XNtK1yDF6hmNE1oYG/lspEsONrAH3Nt2htRF4 2XNnPuOIeqnCJIEgYpElo6je5bgzr0uHpqR748XwCsLdGw7yeVTEdtQaGEtMm1wIf/K9 RQyQ== X-Gm-Message-State: AOAM531XBGLzphWZNRPbRQoIq9rdnEgrvslQ7ogWbsPa1A2pD80BQZt3 HNT3PCwADj/xHNd9A7OXD4Bp82IhO/5rX5BhUUlb64KOd0rKx1f9YRy4UfdusVg4Jrtf76xDwxo bLZqq0lG3qasW4cDT X-Received: by 2002:a5d:4e8c:: with SMTP id e12mr13338133wru.194.1590853899103; Sat, 30 May 2020 08:51:39 -0700 (PDT) X-Google-Smtp-Source: ABdhPJxIayqCnq1HFd4eXHCYr76m1nhJFdgaM+ickdPUSPCiNQxWvhJLM14kvS0e9RzDtWJSEg0rkg== X-Received: by 2002:a5d:4e8c:: with SMTP id e12mr13338120wru.194.1590853898937; Sat, 30 May 2020 08:51:38 -0700 (PDT) Received: from pc-3.home (2a01cb058918ce00dd1a5a4f9908f2d5.ipv6.abo.wanadoo.fr. [2a01:cb05:8918:ce00:dd1a:5a4f:9908:f2d5]) by smtp.gmail.com with ESMTPSA id a124sm4435553wmh.4.2020.05.30.08.51.38 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 30 May 2020 08:51:38 -0700 (PDT) Date: Sat, 30 May 2020 17:51:36 +0200 From: Guillaume Nault To: Eric Dumazet Cc: "David S . Miller" , netdev , Eric Dumazet , James Chapman , syzbot Subject: Re: [PATCH net] l2tp: add sk_family checks to l2tp_validate_socket Message-ID: <20200530155136.GA31596@pc-3.home> References: <20200529183225.150288-1-edumazet@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200529183225.150288-1-edumazet@google.com> Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Fri, May 29, 2020 at 11:32:25AM -0700, Eric Dumazet wrote: > syzbot was able to trigger a crash after using an ISDN socket > and fool l2tp. > > Fix this by making sure the UDP socket is of the proper family. > > --- a/net/l2tp/l2tp_core.c > +++ b/net/l2tp/l2tp_core.c > @@ -1458,6 +1458,9 @@ static int l2tp_validate_socket(const struct sock *sk, const struct net *net, > if (sk->sk_type != SOCK_DGRAM) > return -EPROTONOSUPPORT; > > + if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6) > + return -EPROTONOSUPPORT; > + > if ((encap == L2TP_ENCAPTYPE_UDP && sk->sk_protocol != IPPROTO_UDP) || > (encap == L2TP_ENCAPTYPE_IP && sk->sk_protocol != IPPROTO_L2TP)) > return -EPROTONOSUPPORT; > Thanks a lot! Acked-by: Guillaume Nault