From patchwork Sat May 29 06:05:26 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Changbin Du X-Patchwork-Id: 450256 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=-15.8 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,USER_AGENT_GIT 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 E674AC47082 for ; Sat, 29 May 2021 06:05:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A3F5661186 for ; Sat, 29 May 2021 06:05:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229667AbhE2GHL (ORCPT ); Sat, 29 May 2021 02:07:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40440 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229547AbhE2GHK (ORCPT ); Sat, 29 May 2021 02:07:10 -0400 Received: from mail-pj1-x102b.google.com (mail-pj1-x102b.google.com [IPv6:2607:f8b0:4864:20::102b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 82EAFC061574; Fri, 28 May 2021 23:05:33 -0700 (PDT) Received: by mail-pj1-x102b.google.com with SMTP id pi6-20020a17090b1e46b029015cec51d7cdso3694249pjb.5; Fri, 28 May 2021 23:05:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=dj+sVpS2uayKHiIJ1N88jZYGI1O1BdFKfgWRCDtgcRw=; b=oBmxC+MnK9tUUJJeZJufxG9NHq6kIQQY6R/LuZVLQ1FItodhfhciBM8szGm+onRt+V sJuT9r/hTu+8FGSjHRwM4W23A/aKAPgxuEnjWPC9Ys4gpC8ZjJfKVcowoY0qkiFXiqwe YHtdljdCNhQAllPwxV5IvA8r/4QYgzFFJ7X9Wm+XC5cMQtQgKRnOUXCv4JfmRTCMVpSj qaddp1VvIN9DKDGkuzDb18YknshlgbUS5EykGhN11mQ/Gh+XK/Weoz2ESOl7bhzLJ2Kn kVsglDU/IcTpy8YPCxwOfZIlmvkjKMyOs37r0ILDIIMYBd2n2vuy0Va40IcmbZZJaIX1 oJkA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=dj+sVpS2uayKHiIJ1N88jZYGI1O1BdFKfgWRCDtgcRw=; b=H2BajBvPSc2we4zKO69pzUc7BfgLV13Zl5eMWsoyGZeharnJR+qF7O9ov3LNUZ4ryt uvdZ8rqmDsoBWnM1U/6bKVMKGLGh2MP4QO5jcBM4FWwsiWsJH07XJhSoRYIGqLqNPViy M8PdHrs8Y2fmWwn5A/LhAWvxlTnhaakuK+8K89AClgccxjauloIjlhOhp1nz12cHhN2p paT1bBi0R8WadlflWiz1+b2Vd6qT+8fYdUW+D+zpg+J9LH3IapCElskzIOA04XVm6+Xt 86+AKzq2YuJ5HTGwkVhkk377IsLF6nE8PuNrt4ca8MFeVTzjUFvcTzicagbflMDZIV4U WBjQ== X-Gm-Message-State: AOAM530VrVzsRUvq9SOg/xdwklCf2YxQVAEC4Mclv7WzNUD32U+zndwt FCAYMYA2utaum23XO0jD0UA= X-Google-Smtp-Source: ABdhPJzJk51CMG+RbBrsd/wxt+xHRmOmoRQjW/Qa/nDEtITWWRgyGAkJkaAnPaWE3UlY/yzLqkCysg== X-Received: by 2002:a17:90a:d482:: with SMTP id s2mr8407870pju.230.1622268332834; Fri, 28 May 2021 23:05:32 -0700 (PDT) Received: from vultr.guest ([141.164.41.4]) by smtp.gmail.com with ESMTPSA id u4sm5841520pgl.43.2021.05.28.23.05.30 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 28 May 2021 23:05:32 -0700 (PDT) From: Changbin Du To: "David S. Miller" , Jakub Kici nski Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Changbin Du , stable@vger.kernel.org Subject: [PATCH] net: fix oops in socket ioctl cmd SIOCGSKNS when NET_NS is disabled Date: Sat, 29 May 2021 14:05:26 +0800 Message-Id: <20210529060526.422987-1-changbin.du@gmail.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org 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 --- net/socket.c | 4 ++++ 1 file changed, 4 insertions(+) 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); +#else + err = -ENOTSUPP; +#endif break; case SIOCGSTAMP_OLD: case SIOCGSTAMPNS_OLD: