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=-8.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 424FBC76194 for ; Mon, 22 Jul 2019 10:13:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 26A61218BE for ; Mon, 22 Jul 2019 10:13:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729143AbfGVKNK (ORCPT ); Mon, 22 Jul 2019 06:13:10 -0400 Received: from www262.sakura.ne.jp ([202.181.97.72]:51583 "EHLO www262.sakura.ne.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726846AbfGVKNK (ORCPT ); Mon, 22 Jul 2019 06:13:10 -0400 Received: from fsav104.sakura.ne.jp (fsav104.sakura.ne.jp [27.133.134.231]) by www262.sakura.ne.jp (8.15.2/8.15.2) with ESMTP id x6MACgmF054823; Mon, 22 Jul 2019 19:12:42 +0900 (JST) (envelope-from penguin-kernel@i-love.sakura.ne.jp) Received: from www262.sakura.ne.jp (202.181.97.72) by fsav104.sakura.ne.jp (F-Secure/fsigk_smtp/530/fsav104.sakura.ne.jp); Mon, 22 Jul 2019 19:12:42 +0900 (JST) X-Virus-Status: clean(F-Secure/fsigk_smtp/530/fsav104.sakura.ne.jp) Received: from [192.168.1.8] (softbank126012062002.bbtec.net [126.12.62.2]) (authenticated bits=0) by www262.sakura.ne.jp (8.15.2/8.15.2) with ESMTPSA id x6MACf89054813 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NO); Mon, 22 Jul 2019 19:12:42 +0900 (JST) (envelope-from penguin-kernel@i-love.sakura.ne.jp) Subject: Re: [PATCH 02/10] vfs: syscall: Add move_mount(2) to move mounts around From: Tetsuo Handa To: John Johansen Cc: "Eric W. Biederman" , Al Viro , David Howells , linux-api@vger.kernel.org, linux-fsdevel@vger.kernel.org, torvalds@linux-foundation.org, linux-security-module@vger.kernel.org References: <155059610368.17079.2220554006494174417.stgit@warthog.procyon.org.uk> <155059611887.17079.12991580316407924257.stgit@warthog.procyon.org.uk> <20190708131831.GT17978@ZenIV.linux.org.uk> <874l3wo3gq.fsf@xmission.com> <20190708180132.GU17978@ZenIV.linux.org.uk> <20190708202124.GX17978@ZenIV.linux.org.uk> <87pnmkhxoy.fsf@xmission.com> <5802b8b1-f734-1670-f83b-465eda133936@i-love.sakura.ne.jp> Message-ID: <1698ec76-f56c-1e65-2f11-318c0ed225bb@i-love.sakura.ne.jp> Date: Mon, 22 Jul 2019 19:12:43 +0900 User-Agent: Mozilla/5.0 (Windows NT 6.3; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <5802b8b1-f734-1670-f83b-465eda133936@i-love.sakura.ne.jp> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: I did not see AppArmor patch for this problem in 5.3-rc1. John, are you OK with this patch for 5.2-stable and 5.3 ? On 2019/07/09 19:51, Tetsuo Handa wrote: > For now, can we apply this patch for 5.2-stable ? > > >>>From dd62fab0592e02580fd5a34222a2d11bfc179f61 Mon Sep 17 00:00:00 2001 > From: Tetsuo Handa > Date: Tue, 9 Jul 2019 19:05:49 +0900 > Subject: [PATCH] LSM: Disable move_mount() syscall when TOMOYO or AppArmor is enabled. > > Commit 2db154b3ea8e14b0 ("vfs: syscall: Add move_mount(2) to move mounts > around") introduced security_move_mount() LSM hook, but we missed that > TOMOYO and AppArmor did not implement hooks for checking move_mount(2). > For pathname based access controls like TOMOYO and AppArmor, unchecked > mount manipulation is not acceptable. Therefore, until TOMOYO and AppArmor > implement hooks, in order to avoid unchecked mount manipulation, pretend > as if move_mount(2) is unavailable when either TOMOYO or AppArmor is > enabled. > > Signed-off-by: Tetsuo Handa > Fixes: 2db154b3ea8e14b0 ("vfs: syscall: Add move_mount(2) to move mounts around") > Cc: stable@vger.kernel.org # 5.2 > --- > include/linux/lsm_hooks.h | 6 ++++++ > security/apparmor/lsm.c | 1 + > security/tomoyo/tomoyo.c | 1 + > 3 files changed, 8 insertions(+) > > diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h > index 47f58cf..cd411b7 100644 > --- a/include/linux/lsm_hooks.h > +++ b/include/linux/lsm_hooks.h > @@ -2142,4 +2142,10 @@ static inline void security_delete_hooks(struct security_hook_list *hooks, > > extern int lsm_inode_alloc(struct inode *inode); > > +static inline int no_move_mount(const struct path *from_path, > + const struct path *to_path) > +{ > + return -ENOSYS; > +} > + > #endif /* ! __LINUX_LSM_HOOKS_H */ > diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c > index ec3a928..5cdf63b 100644 > --- a/security/apparmor/lsm.c > +++ b/security/apparmor/lsm.c > @@ -1158,6 +1158,7 @@ struct lsm_blob_sizes apparmor_blob_sizes __lsm_ro_after_init = { > LSM_HOOK_INIT(capable, apparmor_capable), > > LSM_HOOK_INIT(sb_mount, apparmor_sb_mount), > + LSM_HOOK_INIT(move_mount, no_move_mount), > LSM_HOOK_INIT(sb_umount, apparmor_sb_umount), > LSM_HOOK_INIT(sb_pivotroot, apparmor_sb_pivotroot), > > diff --git a/security/tomoyo/tomoyo.c b/security/tomoyo/tomoyo.c > index 716c92e..be1b1a1 100644 > --- a/security/tomoyo/tomoyo.c > +++ b/security/tomoyo/tomoyo.c > @@ -558,6 +558,7 @@ static void tomoyo_task_free(struct task_struct *task) > LSM_HOOK_INIT(path_chown, tomoyo_path_chown), > LSM_HOOK_INIT(path_chroot, tomoyo_path_chroot), > LSM_HOOK_INIT(sb_mount, tomoyo_sb_mount), > + LSM_HOOK_INIT(move_mount, no_move_mount), > LSM_HOOK_INIT(sb_umount, tomoyo_sb_umount), > LSM_HOOK_INIT(sb_pivotroot, tomoyo_sb_pivotroot), > LSM_HOOK_INIT(socket_bind, tomoyo_socket_bind), >