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=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,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 B7911C43381 for ; Mon, 25 Feb 2019 18:41:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8D72120652 for ; Mon, 25 Feb 2019 18:41:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728889AbfBYSl6 (ORCPT ); Mon, 25 Feb 2019 13:41:58 -0500 Received: from shards.monkeyblade.net ([23.128.96.9]:43770 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725936AbfBYSl6 (ORCPT ); Mon, 25 Feb 2019 13:41:58 -0500 Received: from localhost (unknown [IPv6:2601:601:9f80:35cd::bf5]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) (Authenticated sender: davem-davemloft) by shards.monkeyblade.net (Postfix) with ESMTPSA id 14B2D14EE240E; Mon, 25 Feb 2019 10:41:57 -0800 (PST) Date: Mon, 25 Feb 2019 10:41:56 -0800 (PST) Message-Id: <20190225.104156.1331861489514486019.davem@davemloft.net> To: ebiggers@kernel.org Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, maowenan@huawei.com, xiyou.wangcong@gmail.com, lorenzo@google.com, penguin-kernel@i-love.sakura.ne.jp, viro@zeniv.linux.org.uk Subject: Re: [PATCH net] net: socket: set sock->sk to NULL after calling proto_ops::release() From: David Miller In-Reply-To: <20190221221356.173485-1-ebiggers@kernel.org> References: <20190221221356.173485-1-ebiggers@kernel.org> X-Mailer: Mew version 6.8 on Emacs 26.1 Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Mon, 25 Feb 2019 10:41:57 -0800 (PST) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Eric Biggers Date: Thu, 21 Feb 2019 14:13:56 -0800 > From: Eric Biggers > > Commit 9060cb719e61 ("net: crypto set sk to NULL when af_alg_release.") > fixed a use-after-free in sockfs_setattr() when an AF_ALG socket is > closed concurrently with fchownat(). However, it ignored that many > other proto_ops::release() methods don't set sock->sk to NULL and > therefore allow the same use-after-free: ... > Rather than fixing all these and relying on every socket type to get > this right forever, just make __sock_release() set sock->sk to NULL > itself after calling proto_ops::release(). > > Reproducer that produces the KASAN splat when any of these socket types > are configured into the kernel: ... > Fixes: 86741ec25462 ("net: core: Add a UID field to struct sock.") > Signed-off-by: Eric Biggers Applied and queued up for -stable, thanks Eric.