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=-12.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 29502C47082 for ; Mon, 31 May 2021 17:15:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 059A66108D for ; Mon, 31 May 2021 17:15:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233218AbhEaRRT (ORCPT ); Mon, 31 May 2021 13:17:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51992 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233480AbhEaRPn (ORCPT ); Mon, 31 May 2021 13:15:43 -0400 Received: from mail-pj1-x102a.google.com (mail-pj1-x102a.google.com [IPv6:2607:f8b0:4864:20::102a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 63606C0611EB; Mon, 31 May 2021 08:29:07 -0700 (PDT) Received: by mail-pj1-x102a.google.com with SMTP id k22-20020a17090aef16b0290163512accedso128947pjz.0; Mon, 31 May 2021 08:29:07 -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=R3ERwvWAJQeMnwLML6I5CNggHBvI3ijt6irwEhA0CSU=; b=ZjcWRA2zVVf2u39IwROdRm+73SIR4lpLX33ihPFpccyUmmwKGXuEURi0bGu4ChqTds qbWYG7Ryuo/jLZeeXHauSo899ebOPGJ9UIr2EkiM//zBZcok6/ELX79M6ZqIdWEksGOV lSuljF4vJqYpWRlmsJB2tMuqpqgxVajKZO/q3dLh/26/ghOonKlPwxqxSJ7ZkJFdA1cR C2zlYiuSeJ5EKIsIqhq0Ww3jwn+xPLMNrjEJy4r+fbqgBXQWk7HkSpfAJJPvp1/BztMK /Ze895BJAIxsRCi3pGceCSh/CP6Nql9so5EzCN93ySHKrawSCQgjdiqOnqu5AJEaFHVP /GUw== 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=R3ERwvWAJQeMnwLML6I5CNggHBvI3ijt6irwEhA0CSU=; b=UEIB1Lty8JBvtPbqWmBG3dRXo513wC5cdFIpiBt2uMuLo7phjm3p5V8vcZX0e6hn72 GJnwJQP/ClCIRiED4+LY9FjgEsAiV+hkVLesHAJv7fOtuNOZtC08+nOG3hY8rDfxJ7YT FrU/QhW0Zo8sDVAxcVOxQELw1rcLljlrApZugezXnFDW9qK09muTlsubz0WmEiUZxmxu bQ2Yo4aGXybNyIxrfMTJWKJ9uZgNtIj8w1OCwjkt0QzORrqU78c5VzpqC7KZB8eDnDz7 wCxAc8/+LTrxRlPjuTLXNoAfdaL4ZHek4hb8i/5lZtHwqKBbEUJX6KWsBvuPspXg1ok+ g3ug== X-Gm-Message-State: AOAM532COuGdn0j1MPjtacfmVK+/AzKTPcFs/g0sYJ4lYiqz9U0rhOtL fQXlJVoXBNKAA+I3i0SyjsI= X-Google-Smtp-Source: ABdhPJxzmBuYkOtFsW5fXmvfOuELbxqIAdDR2FQ12ZJ1ILKtDC6SzoIpta8D6y5gWAqw7OkY0VqRHA== X-Received: by 2002:a17:903:2482:b029:fd:696c:1d2b with SMTP id p2-20020a1709032482b02900fd696c1d2bmr21292801plw.24.1622474946893; Mon, 31 May 2021 08:29:06 -0700 (PDT) Received: from mail.google.com ([141.164.41.4]) by smtp.gmail.com with ESMTPSA id t13sm4319859pfh.97.2021.05.31.08.29.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 31 May 2021 08:29:06 -0700 (PDT) Date: Mon, 31 May 2021 23:28:58 +0800 From: Changbin Du To: Jakub Kicinski Cc: Changbin Du , "David S. Miller" , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: Re: [PATCH] net: fix oops in socket ioctl cmd SIOCGSKNS when NET_NS is disabled Message-ID: <20210531152858.nz2orstfcm2bwvjr@mail.google.com> References: <20210529060526.422987-1-changbin.du@gmail.com> <20210529112735.22bdc153@kicinski-fedora-PC1C0HJN.hsd1.ca.comcast.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210529112735.22bdc153@kicinski-fedora-PC1C0HJN.hsd1.ca.comcast.net> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, May 29, 2021 at 11:27:35AM -0700, Jakub Kicinski wrote: > On Sat, 29 May 2021 14:05:26 +0800 Changbin Du wrote: > > When NET_NS is not enabled, socket ioctl cmd SIOCGSKNS should do nothing > > but acknowledge userspace it is not supported. Otherwise, kernel would > > panic wherever nsfs trys to access ns->ops since the proc_ns_operations > > is not implemented in this case. > > > > [7.670023] Unable to handle kernel NULL pointer dereference at virtual address 00000010 > > [7.670268] pgd = 32b54000 > > [7.670544] [00000010] *pgd=00000000 > > [7.671861] Internal error: Oops: 5 [#1] SMP ARM > > [7.672315] Modules linked in: > > [7.672918] CPU: 0 PID: 1 Comm: systemd Not tainted 5.13.0-rc3-00375-g6799d4f2da49 #16 > > [7.673309] Hardware name: Generic DT based system > > [7.673642] PC is at nsfs_evict+0x24/0x30 > > [7.674486] LR is at clear_inode+0x20/0x9c > > > > Signed-off-by: Changbin Du > > Cc: # v4.9 > > Please provide a Fixes tag. > Now it will be fixed by nsfs side. And the code has been changed to many times.. > > diff --git a/net/socket.c b/net/socket.c > > index 27e3e7d53f8e..644b46112d35 100644 > > --- a/net/socket.c > > +++ b/net/socket.c > > @@ -1149,11 +1149,15 @@ static long sock_ioctl(struct file *file, unsigned cmd, unsigned long arg) > > mutex_unlock(&vlan_ioctl_mutex); > > break; > > case SIOCGSKNS: > > +#ifdef CONFIG_NET_NS > > err = -EPERM; > > if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) > > break; > > > > err = open_related_ns(&net->ns, get_net_ns); > > There's a few more places with this exact code. Can we please add the > check in get_net_ns? That should fix all callers. > > > +#else > > + err = -ENOTSUPP; > > EOPNOTSUPP, you shouldn't return ENOTSUPP to user space. > Thanks for pointing out. Will change it. > > +#endif > > break; > > case SIOCGSTAMP_OLD: > > case SIOCGSTAMPNS_OLD: > -- Cheers, Changbin Du