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=-9.6 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS autolearn=ham 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 69F71C43464 for ; Fri, 18 Sep 2020 13:30:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 03DB5235FA for ; Fri, 18 Sep 2020 13:30:02 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="iaE8JMtg" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726619AbgIRNaC (ORCPT ); Fri, 18 Sep 2020 09:30:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46736 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726126AbgIRNaC (ORCPT ); Fri, 18 Sep 2020 09:30:02 -0400 Received: from mail-qt1-x844.google.com (mail-qt1-x844.google.com [IPv6:2607:f8b0:4864:20::844]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 08894C0613CE; Fri, 18 Sep 2020 06:30:02 -0700 (PDT) Received: by mail-qt1-x844.google.com with SMTP id n10so4923297qtv.3; Fri, 18 Sep 2020 06:30:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=vASDjEll6360SujAnjlOkOkT4JdvbE9lhOhXWeoPleE=; b=iaE8JMtgxMFET5j8BgD9mRCKX/eq0V3KVrnKyozizQNZ/SK2gOuiy9LuDCcd5wN9yo ZiYisPuSzE/UqpsvLSxzY7O/J0x+MCPvX/9+kLqhkoqljp38LRLoFFnkaax1TtE8bVof pVLq0q0gY+yuypZK42If1I+/HfvlPUvypPQYZG/AX/Ko929il5wWQXDijPvUzgWO9YMl nzChB4l2bH9/YXxDoN72CKoM9/hIcifgZ7GPxQecPmcKF78/PFbUzl1ib0JM+Mj4zz1T c90HOkfg3+k+fuiDt8WMpHvcM8+PCKlVNKFlaCwNMvIhlAOJNpTzAcbqiDjGnaNHyiu7 H15g== 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=vASDjEll6360SujAnjlOkOkT4JdvbE9lhOhXWeoPleE=; b=NVMH+zNvBs+eVauhg8f2mONNvFMAs+3Rg43MvRu2VPxCpTytD5NxAeBa6GMubsCCw6 HPqgDHT3wgnP78ZqyntMaO7AmKPdOivzIFAGL0Xz1CjJQiOGiizC8a7enkTx08qn5tjM gndKqIH6ph1//AIBpnQjoUEPH9R2T/4nFrpIcGo7AZHPGx1iS9dMMWudN3R8s7Uuw84W CFmwRW9BwslFZw9Eja6ubvZ5bGOMUDOFRlQ35ZjWVR4tZgtlQxYn9J1FK+Gk4Mk1u2st dnYkroM4+/iqnS3OJ/gUxCr3hpkABYn8yAdm5pA9ogztXZY3GFBt7Xv2Y8uyuH6j05wN jSMQ== X-Gm-Message-State: AOAM530k3rxTfmHZ3bACOx7Zwf/EpCu3KLk3OkhvVhSuEDTsDMzULHVK U/+u98BuOUdZi3Drtwsl6t8= X-Google-Smtp-Source: ABdhPJwP89l58R0b0P2ljD2Q/hpiLcFOLGbgRZjclDShsIg/UelGnTmLNnAFslgB0yxcJKURjsYOeg== X-Received: by 2002:ac8:1488:: with SMTP id l8mr33223704qtj.131.1600435801141; Fri, 18 Sep 2020 06:30:01 -0700 (PDT) Received: from localhost.localdomain ([2001:1284:f013:eda9:8c35:6fe5:a04c:832]) by smtp.gmail.com with ESMTPSA id p3sm1996690qkj.113.2020.09.18.06.29.59 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 18 Sep 2020 06:30:00 -0700 (PDT) Received: by localhost.localdomain (Postfix, from userid 1000) id C354BC1D68; Fri, 18 Sep 2020 10:29:57 -0300 (-03) Date: Fri, 18 Sep 2020 10:29:57 -0300 From: Marcelo Ricardo Leitner To: Henry Ptasinski Cc: linux-sctp@vger.kernel.org, netdev@vger.kernel.org, Vlad Yasevich , Neil Horman , "David S . Miller" , Jakub Kicinski , Corey Minyard Subject: Re: [PATCH] net: sctp: Fix IPv6 ancestor_size calc in sctp_copy_descendant Message-ID: <20200918132957.GB82043@localhost.localdomain> References: <20200918015610.3596417-1-hptasinski@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200918015610.3596417-1-hptasinski@google.com> Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Fri, Sep 18, 2020 at 01:56:10AM +0000, Henry Ptasinski wrote: > When calculating ancestor_size with IPv6 enabled, simply using > sizeof(struct ipv6_pinfo) doesn't account for extra bytes needed for > alignment in the struct sctp6_sock. On x86, there aren't any extra > bytes, but on ARM the ipv6_pinfo structure is aligned on an 8-byte > boundary so there were 4 pad bytes that were omitted from the > ancestor_size calculation. This would lead to corruption of the > pd_lobby pointers, causing an oops when trying to free the sctp > structure on socket close. Makes sense. > > Signed-off-by: Henry Ptasinski Please add a: Fixes: 636d25d557d1 ("sctp: not copy sctp_sock pd_lobby in sctp_copy_descendant") > --- > net/sctp/socket.c | 10 ++++++---- > 1 file changed, 6 insertions(+), 4 deletions(-) > > diff --git a/net/sctp/socket.c b/net/sctp/socket.c > index 836615f71a7d..a6358c81f087 100644 > --- a/net/sctp/socket.c > +++ b/net/sctp/socket.c > @@ -9220,12 +9220,14 @@ void sctp_copy_sock(struct sock *newsk, struct sock *sk, > static inline void sctp_copy_descendant(struct sock *sk_to, ^^^^^^ I'll send a patch to fix/remove this. > const struct sock *sk_from) > { > - int ancestor_size = sizeof(struct inet_sock) + > - sizeof(struct sctp_sock) - > - offsetof(struct sctp_sock, pd_lobby); ^^^^^^^^ Then, as this patch is actually fixing the aforementioned commit, please also update the comment on sctp_sock definition, as pd_lobby now is also skipped. > + size_t ancestor_size = sizeof(struct inet_sock); > > if (sk_from->sk_family == PF_INET6) > - ancestor_size += sizeof(struct ipv6_pinfo); > + ancestor_size += sizeof(struct sctp6_sock); As you probably noticed by the build bot email already, there need to be some protection to building without IPv6 enabled. To avoid ifdefs here, something similar to how inet_sk_copy_descendant() is done is probably welcomed, but please feel free to be creative. :-) > + else > + ancestor_size += sizeof(struct sctp_sock); > + > + ancestor_size -= offsetof(struct sctp_sock, pd_lobby); > > __inet_sk_copy_descendant(sk_to, sk_from, ancestor_size); > } > -- > 2.28.0.681.g6f77f65b4e-goog >