From nobody Sun Jun 28 08:36:27 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 210BEC433F5 for ; Wed, 9 Feb 2022 19:17:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232237AbiBITR2 (ORCPT ); Wed, 9 Feb 2022 14:17:28 -0500 Received: from gmail-smtp-in.l.google.com ([23.128.96.19]:49772 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229696AbiBITRX (ORCPT ); Wed, 9 Feb 2022 14:17:23 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 57E17C1DF8E8; Wed, 9 Feb 2022 11:17:17 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 01446B82381; Wed, 9 Feb 2022 19:15:11 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 39060C340E7; Wed, 9 Feb 2022 19:15:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1644434109; bh=eDuTti1Xl3WBHB7wzjkGc4GxcUg/vQ6edwJO2tDO8Hw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=uP6HYqcpZqXRle2c+2R/u2a7OKXmowgwUk9ArLx7RU6PHdRSYYqnDm8yr9/MeRiDa yzZ+8IQGbCdXjebdBhta0RS9Bi2g92UoKudw9B0hyWv0o0DifOUjteAOMnmeaqnjmz QUjHmngd8CaVPWY16kNmaDKaHWIFnaEQTkxCJCSE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Tabitha Sable , "Eric W. Biederman" , Tejun Heo , =?UTF-8?q?Michal=20Koutn=C3=BD?= Subject: [PATCH 4.19 1/2] cgroup-v1: Require capabilities to set release_agent Date: Wed, 9 Feb 2022 20:14:03 +0100 Message-Id: <20220209191248.652388187@linuxfoundation.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220209191248.596319706@linuxfoundation.org> References: <20220209191248.596319706@linuxfoundation.org> User-Agent: quilt/0.66 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Eric W. Biederman commit 24f6008564183aa120d07c03d9289519c2fe02af upstream. The cgroup release_agent is called with call_usermodehelper. The function call_usermodehelper starts the release_agent with a full set fo capabilitie= s. Therefore require capabilities when setting the release_agaent. Reported-by: Tabitha Sable Tested-by: Tabitha Sable Fixes: 81a6a5cdd2c5 ("Task Control Groups: automatic userspace notification= of idle cgroups") Cc: stable@vger.kernel.org # v2.6.24+ Signed-off-by: "Eric W. Biederman" Signed-off-by: Tejun Heo [mkoutny: Adjust for pre-fs_context, duplicate mount/remount check, drop lo= g messages.] Acked-by: Michal Koutn=C3=BD Signed-off-by: Greg Kroah-Hartman Tested-by: Guenter Roeck Tested-by: Hulk Robot Tested-by: Jeffrin Jose T Tested-by: Linux Kernel Functional Testing Tested-by: Pavel Machek (CIP) Tested-by: Shuah Khan Tested-by: Sudip Mukherjee --- kernel/cgroup/cgroup-v1.c | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) --- a/kernel/cgroup/cgroup-v1.c +++ b/kernel/cgroup/cgroup-v1.c @@ -577,6 +577,14 @@ static ssize_t cgroup_release_agent_writ =20 BUILD_BUG_ON(sizeof(cgrp->root->release_agent_path) < PATH_MAX); =20 + /* + * Release agent gets called with all capabilities, + * require capabilities to set release agent. + */ + if ((of->file->f_cred->user_ns !=3D &init_user_ns) || + !capable(CAP_SYS_ADMIN)) + return -EPERM; + cgrp =3D cgroup_kn_lock_live(of->kn, false); if (!cgrp) return -ENODEV; @@ -1048,6 +1056,7 @@ static int cgroup1_remount(struct kernfs { int ret =3D 0; struct cgroup_root *root =3D cgroup_root_from_kf(kf_root); + struct cgroup_namespace *ns =3D current->nsproxy->cgroup_ns; struct cgroup_sb_opts opts; u16 added_mask, removed_mask; =20 @@ -1061,6 +1070,12 @@ static int cgroup1_remount(struct kernfs if (opts.subsys_mask !=3D root->subsys_mask || opts.release_agent) pr_warn("option changes via remount are deprecated (pid=3D%d comm=3D%s)\= n", task_tgid_nr(current), current->comm); + /* See cgroup1_mount release_agent handling */ + if (opts.release_agent && + ((ns->user_ns !=3D &init_user_ns) || !capable(CAP_SYS_ADMIN))) { + ret =3D -EINVAL; + goto out_unlock; + } =20 added_mask =3D opts.subsys_mask & ~root->subsys_mask; removed_mask =3D root->subsys_mask & ~opts.subsys_mask; @@ -1224,6 +1239,15 @@ struct dentry *cgroup1_mount(struct file ret =3D -EPERM; goto out_unlock; } + /* + * Release agent gets called with all capabilities, + * require capabilities to set release agent. + */ + if (opts.release_agent && + ((ns->user_ns !=3D &init_user_ns) || !capable(CAP_SYS_ADMIN))) { + ret =3D -EINVAL; + goto out_unlock; + } =20 root =3D kzalloc(sizeof(*root), GFP_KERNEL); if (!root) { From nobody Sun Jun 28 08:36:27 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 72AADC43217 for ; Wed, 9 Feb 2022 19:17:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231704AbiBITRi (ORCPT ); Wed, 9 Feb 2022 14:17:38 -0500 Received: from gmail-smtp-in.l.google.com ([23.128.96.19]:50102 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233098AbiBITR0 (ORCPT ); Wed, 9 Feb 2022 14:17:26 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 40C26C0F8692; Wed, 9 Feb 2022 11:17:21 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 0868AB82399; Wed, 9 Feb 2022 19:15:14 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 382E9C340E7; Wed, 9 Feb 2022 19:15:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1644434112; bh=dCxPR4JBeSv02HURTnL42udmBp2yb2pJ1Ew0FokUAEM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kqbuinsX3+4H6y7jzBhRE5piA+qUZMz2QPFsSb9yF+yBp4s3jVive7d657Ww194af Aw43WzAL4SebE7wit/Y/gnEWwzDsiGIhMO2d9dtYwgIuSwz7AUVt8v8Mjfy2po3f6A +ga/dZDC+I+fKL8hmZuZ3hAcTdbcm+EP3EZQ1ySc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Ulf Hansson , Xiyu Yang , Xin Xiong , Xin Tan , Tony Lindgren , Yang Li , linux-mmc@vger.kernel.org, whitehat002 Subject: [PATCH 4.19 2/2] moxart: fix potential use-after-free on remove path Date: Wed, 9 Feb 2022 20:14:04 +0100 Message-Id: <20220209191248.685713468@linuxfoundation.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220209191248.596319706@linuxfoundation.org> References: <20220209191248.596319706@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Greg Kroah-Hartman commit bd2db32e7c3e35bd4d9b8bbff689434a50893546 upstream. It was reported that the mmc host structure could be accessed after it was freed in moxart_remove(), so fix this by saving the base register of the device and using it instead of the pointer dereference. Cc: Ulf Hansson Cc: Xiyu Yang Cc: Xin Xiong Cc: Xin Tan Cc: Tony Lindgren Cc: Yang Li Cc: linux-mmc@vger.kernel.org Cc: stable Reported-by: whitehat002 Signed-off-by: Greg Kroah-Hartman Link: https://lore.kernel.org/r/20220127071638.4057899-1-gregkh@linuxfounda= tion.org Signed-off-by: Ulf Hansson Signed-off-by: Greg Kroah-Hartman Tested-by: Guenter Roeck Tested-by: Hulk Robot Tested-by: Jeffrin Jose T Tested-by: Linux Kernel Functional Testing Tested-by: Pavel Machek (CIP) Tested-by: Shuah Khan Tested-by: Sudip Mukherjee --- drivers/mmc/host/moxart-mmc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/mmc/host/moxart-mmc.c +++ b/drivers/mmc/host/moxart-mmc.c @@ -696,12 +696,12 @@ static int moxart_remove(struct platform if (!IS_ERR(host->dma_chan_rx)) dma_release_channel(host->dma_chan_rx); mmc_remove_host(mmc); - mmc_free_host(mmc); =20 writel(0, host->base + REG_INTERRUPT_MASK); writel(0, host->base + REG_POWER_CONTROL); writel(readl(host->base + REG_CLOCK_CONTROL) | CLK_OFF, host->base + REG_CLOCK_CONTROL); + mmc_free_host(mmc); } return 0; }