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=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_MUTT 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 A263CC43613 for ; Thu, 20 Jun 2019 14:04:00 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 778182075E for ; Thu, 20 Jun 2019 14:04:00 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="b1UowkdF" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 778182075E Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.cz Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-mtd-bounces+linux-mtd=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=YGCo3MX3mxbkrXmMm5USkToDmPDtTKv6ddF1tqDr5gs=; b=b1UowkdFEnBdP6 q/6iYzjShW+geHkMIm2qNEYcwedS8a/4aTY0llg29Npb/cXArLf/84zgQ4Zb0UwLTTl6nsg4doE7C OqNOlmSEEfPdPNwA0kbC0JmkWug/YKntP1/gIayof8Jse3JZpt/wIr8wSaPz6fD9/2X9moTOQLi14 usT8VxA4+e8CrUTWjdHTN75c7ma5w2wkP6eJrNMMa+l3xffxvkaYUASGNBZt55RbYHSauI4Cn3p6b BQ8ZcpjRP0GPjtrgir6A5cnS9RCE/ZhDqibVuu+bOsLHeZ5h+Mu85NjOi8ccz6rvhdUNCwgIZLgF8 b8q/D4Ayai2DI+96an+g==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92 #3 (Red Hat Linux)) id 1hdxfK-000361-Av; Thu, 20 Jun 2019 14:03:50 +0000 Received: from mx2.suse.de ([195.135.220.15] helo=mx1.suse.de) by bombadil.infradead.org with esmtps (Exim 4.92 #3 (Red Hat Linux)) id 1hdxfH-00035M-FC for linux-mtd@lists.infradead.org; Thu, 20 Jun 2019 14:03:48 +0000 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 05638AF85; Thu, 20 Jun 2019 14:03:46 +0000 (UTC) Received: by quack2.suse.cz (Postfix, from userid 1000) id A12B31E434F; Thu, 20 Jun 2019 16:03:45 +0200 (CEST) Date: Thu, 20 Jun 2019 16:03:45 +0200 From: Jan Kara To: "Darrick J. Wong" Subject: Re: [PATCH 4/6] vfs: don't allow most setxattr to immutable files Message-ID: <20190620140345.GI30243@quack2.suse.cz> References: <156022836912.3227213.13598042497272336695.stgit@magnolia> <156022840560.3227213.4776913678782966728.stgit@magnolia> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <156022840560.3227213.4776913678782966728.stgit@magnolia> User-Agent: Mutt/1.10.1 (2018-07-13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190620_070347_660794_F9686BEA X-CRM114-Status: GOOD ( 18.36 ) X-BeenThere: linux-mtd@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-efi@vger.kernel.org, linux-btrfs@vger.kernel.org, yuchao0@huawei.com, linux-mm@kvack.org, clm@fb.com, adilger.kernel@dilger.ca, matthew.garrett@nebula.com, linux-nilfs@vger.kernel.org, linux-ext4@vger.kernel.org, devel@lists.orangefs.org, josef@toxicpanda.com, reiserfs-devel@vger.kernel.org, viro@zeniv.linux.org.uk, dsterba@suse.com, jaegeuk@kernel.org, tytso@mit.edu, ard.biesheuvel@linaro.org, linux-kernel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-xfs@vger.kernel.org, jk@ozlabs.org, jack@suse.com, linux-fsdevel@vger.kernel.org, linux-mtd@lists.infradead.org, ocfs2-devel@oss.oracle.com Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-mtd" Errors-To: linux-mtd-bounces+linux-mtd=archiver.kernel.org@lists.infradead.org On Mon 10-06-19 21:46:45, Darrick J. Wong wrote: > From: Darrick J. Wong > > The chattr manpage has this to say about immutable files: > > "A file with the 'i' attribute cannot be modified: it cannot be deleted > or renamed, no link can be created to this file, most of the file's > metadata can not be modified, and the file can not be opened in write > mode." > > However, we don't actually check the immutable flag in the setattr code, > which means that we can update inode flags and project ids and extent > size hints on supposedly immutable files. Therefore, reject setflags > and fssetxattr calls on an immutable file if the file is immutable and > will remain that way. > > Signed-off-by: Darrick J. Wong > --- > fs/inode.c | 31 +++++++++++++++++++++++++++++++ > 1 file changed, 31 insertions(+) > > > diff --git a/fs/inode.c b/fs/inode.c > index a3757051fd55..adfb458bf533 100644 > --- a/fs/inode.c > +++ b/fs/inode.c > @@ -2184,6 +2184,17 @@ int vfs_ioc_setflags_check(struct inode *inode, int oldflags, int flags) > !capable(CAP_LINUX_IMMUTABLE)) > return -EPERM; > > + /* > + * We aren't allowed to change any other flags if the immutable flag is > + * already set and is not being unset. > + */ > + if ((oldflags & FS_IMMUTABLE_FL) && > + (flags & FS_IMMUTABLE_FL)) { > + if ((oldflags & ~FS_IMMUTABLE_FL) != > + (flags & ~FS_IMMUTABLE_FL)) This check looks a bit strange when you've just check FS_IMMUTABLE_FL isn't changing... Why not just oldflags != flags? > + if ((old_fa->fsx_xflags & FS_XFLAG_IMMUTABLE) && > + (fa->fsx_xflags & FS_XFLAG_IMMUTABLE)) { > + if ((old_fa->fsx_xflags & ~FS_XFLAG_IMMUTABLE) != > + (fa->fsx_xflags & ~FS_XFLAG_IMMUTABLE)) Ditto here... > + return -EPERM; > + if (old_fa->fsx_projid != fa->fsx_projid) > + return -EPERM; > + if ((fa->fsx_xflags & (FS_XFLAG_EXTSIZE | > + FS_XFLAG_EXTSZINHERIT)) && > + old_fa->fsx_extsize != fa->fsx_extsize) > + return -EPERM; > + if ((old_fa->fsx_xflags & FS_XFLAG_COWEXTSIZE) && > + old_fa->fsx_cowextsize != fa->fsx_cowextsize) > + return -EPERM; > + } > + > /* Extent size hints of zero turn off the flags. */ > if (fa->fsx_extsize == 0) > fa->fsx_xflags &= ~(FS_XFLAG_EXTSIZE | FS_XFLAG_EXTSZINHERIT); Honza -- Jan Kara SUSE Labs, CR ______________________________________________________ Linux MTD discussion mailing list http://lists.infradead.org/mailman/listinfo/linux-mtd/