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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 7FCFAC3ABC9 for ; Tue, 13 May 2025 03:55:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=tH28IR6cEDMJu6Zp6rniPm7B0/eMWW2T/aX6be9+u0c=; b=F98EyVFc3EGGftInskIy44uWma ZyHjYRm+kCcgUqUUgtQ1DAtCN/SABPW2CTVGjZFxJ2FQj58sht6ZEHLWqUddIEBZqKuL3zmT5V6uv DIKoErqOPrATvVlvFlult903PY5aMg1XifzStYRLJUQhd18ghJiidTQBfQ9sSXAxOA6tMdYPPZvzk Jxk4vrKpoWfS54OiR8fC2FcHBLGwQ3eLZO6N9ADdWXAuHFJGfgFqU2CAE429g1iA8Wg4d6r2beDlc upE2dnf9vJxcFMGfkTmRQGkkF2JMPG53uoJ+GQ1Ef+DlQMfXY3Z22bXMH8GMPssBXQkp6OmGx+8b0 TBJYUCNA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1uEgjz-0000000BHBN-17Wl; Tue, 13 May 2025 03:55:39 +0000 Received: from out30-98.freemail.mail.aliyun.com ([115.124.30.98]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1uEgjv-0000000BH9e-39MP for kexec@lists.infradead.org; Tue, 13 May 2025 03:55:38 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1747108528; h=Message-ID:Date:MIME-Version:Subject:To:From:Content-Type; bh=tH28IR6cEDMJu6Zp6rniPm7B0/eMWW2T/aX6be9+u0c=; b=QnSuCW8NmQmaTwybPF6PtvksGCtIhNuGLLenUZoMIuaM80+KeUZy+YNDW6TGwY2KgQmBhEIQDOXmYHRp7WZ5RYXK6mxu91/btxrYOgcgCxiin9DpMwRT8jV/uypeBtOcOJxDz1bJelnSCp0wXu82xMGfF4pAtDTEvL2vj8B0iec= Received: from 30.221.65.46(mailfrom:hsiangkao@linux.alibaba.com fp:SMTPD_---0WaRTmuN_1747108522 cluster:ay36) by smtp.aliyun-inc.com; Tue, 13 May 2025 11:55:23 +0800 Message-ID: <9c4b14de-692a-415d-876f-c72e42aaba6f@linux.alibaba.com> Date: Tue, 13 May 2025 11:55:22 +0800 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RFC PATCH] ima: add a knob to make IMA be able to be disabled To: Coiby Xu Cc: Roberto Sassu , Baoquan He , chenste@linux.microsoft.com, RuiRui Yang , linux-integrity@vger.kernel.org, kexec@lists.infradead.org, Christian Brauner , Mimi Zohar References: <65057b5256a28c3416e6b90a143d741801e68b03.camel@linux.ibm.com> <02563b1e8b0000bedf94ded447a8372f21d4304a.camel@linux.ibm.com> <80766b04cafd24a1d7171b8da03c822d86272f3c.camel@linux.ibm.com> <00d282d0cf06c3ac208ab9edfddedda1c9a5a77b.camel@linux.ibm.com> From: Gao Xiang In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250512_205536_431372_CF3AC86D X-CRM114-Status: GOOD ( 15.10 ) X-BeenThere: kexec@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "kexec" Errors-To: kexec-bounces+kexec=archiver.kernel.org@lists.infradead.org Hi Coiby, On 2025/5/13 08:14, Coiby Xu wrote: > On Fri, May 09, 2025 at 09:03:11AM -0400, Mimi Zohar wrote: ... >>> >>> > I'm aware that some >>> > store the security xattr information in a file and write it out as xattrs. >>> >>> If the built initramfs as a CPIO file doesn't carry xattrs, the loaded >>> initramfs still doesn't have xattrs. I just found the initramfs could >>> opt to use squashfs or erofs which supports xattrs but currently it's >>> hardcoded to disable xattrs. For example, recently the dracut erorfs >>> module also follows squashfs to disable xattrs [1]. So in the near >>> future, I don't expect xattrs to be supported in kdump. >>> >>> [1] https://github.com/dracut-ng/dracut-ng/pull > > Sorry, I didn't notice the link is incomplete. It should be > > [1] https://github.com/dracut-ng/dracut-ng/pull/1296 > >> >> Right, so the issue isn't the initramfs root filesystem, but CPIO.  Either CPIO >> would need to be extended, which multiple people have attempted to do, or the xattrs >> could be stored in a file and written out to the initramfs root filesystem.  In fact >> Roberto's last attempts at adding CPIO xattr support did something like that. >> >> https://lore.kernel.org/linux-integrity/20190523121803.21638-1-roberto.sassu@huawei.com/ > > Thanks for introducing Roberto's work to me! I wrote some words on initramfs vs initrd erofs on related threads: https://lore.kernel.org/r/934af3e3-3153-40c1-9a25-7a8d08fdb007@linux.alibaba.com https://lore.kernel.org/r/582bc002-f0c8-4dbb-8fa5-4c10a479b518@linux.alibaba.com/T/#u The CPIO standard doesn't support xattrs, also initramfs could cause unnecessary unpacking. But anyway it needs more work on this stuff too. Thanks, Gao Xiang > >> >> Mimi >> >