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=-5.0 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,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 599B4C433FF for ; Wed, 14 Aug 2019 11:00:41 +0000 (UTC) Received: from lists.sourceforge.net (lists.sourceforge.net [216.105.38.7]) (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 24F8E206C1; Wed, 14 Aug 2019 11:00:41 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=sourceforge.net header.i=@sourceforge.net header.b="aSBvSI9m"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=sf.net header.i=@sf.net header.b="iU7TIgWl" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 24F8E206C1 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.cz Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linux-f2fs-devel-bounces@lists.sourceforge.net Received: from [127.0.0.1] (helo=sfs-ml-1.v29.lw.sourceforge.com) by sfs-ml-1.v29.lw.sourceforge.com with esmtp (Exim 4.90_1) (envelope-from ) id 1hxr1E-0004j0-Ep; Wed, 14 Aug 2019 11:00:40 +0000 Received: from [172.30.20.202] (helo=mx.sourceforge.net) by sfs-ml-1.v29.lw.sourceforge.com with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.90_1) (envelope-from ) id 1hxr1C-0004iL-CA; Wed, 14 Aug 2019 11:00:38 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sourceforge.net; s=x; h=In-Reply-To:Content-Type:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To:Content-Transfer-Encoding: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=XiZvbx1Cp6Oqyc0YHfIAj22w+8Ky/OkrizB9nmmqcbc=; b=aSBvSI9mxO3SRZP+A43YNUXw0j rToI9vwBaM6pOB4Wq5DVjS1nEjP8Zf8fAb7M3YgyW+2avv16MnIkOlGThNHvMXHSAsxoj1DqblDUA cBvZCLR7XjWrjjUS/yXZop+WEMbFtEHGj3piVUno/YaCfqhVqDn0YAHqkxGIwsVMuRR8=; DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sf.net; s=x ; h=In-Reply-To:Content-Type:MIME-Version:References:Message-ID:Subject:Cc:To :From:Date:Sender:Reply-To:Content-Transfer-Encoding:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=XiZvbx1Cp6Oqyc0YHfIAj22w+8Ky/OkrizB9nmmqcbc=; b=iU7TIgWlvURQegk4quHMTU9nOx SPKmBAoJrR7XMW8qEzxBwOmo/03YmcqZm9+pvE5tTDtmzPsCWX1XHTM1NqPs9fVGiDL2S8PgJ4FIe 3Cu9REuSBpQrSZtM5xlfY70iB0xHU8mhfvR5XnfX1sJUa3iomCL+M8lyUPKnigUm9Ot0=; Received: from mx2.suse.de ([195.135.220.15] helo=mx1.suse.de) by sfi-mx-1.v28.lw.sourceforge.com with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.90_1) id 1hxr18-005pSh-58; Wed, 14 Aug 2019 11:00:38 +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 3537FADEF; Wed, 14 Aug 2019 11:00:26 +0000 (UTC) Received: by quack2.suse.cz (Postfix, from userid 1000) id 81D741E4200; Wed, 14 Aug 2019 13:00:22 +0200 (CEST) Date: Wed, 14 Aug 2019 13:00:22 +0200 From: Jan Kara To: Mark Salyzyn Message-ID: <20190814110022.GB26273@quack2.suse.cz> References: <20190813145527.26289-1-salyzyn@android.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20190813145527.26289-1-salyzyn@android.com> User-Agent: Mutt/1.10.1 (2018-07-13) X-Headers-End: 1hxr18-005pSh-58 Subject: Re: [f2fs-dev] [PATCH v2] Add flags option to get xattr method paired to __vfs_getxattr X-BeenThere: linux-f2fs-devel@lists.sourceforge.net X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Latchesar Ionkov , Dave Kleikamp , jfs-discussion@lists.sourceforge.net, Phillip Lougher , linux-integrity@vger.kernel.org, Martin Brandenburg , samba-technical@lists.samba.org, Dominique Martinet , Mimi Zohar , Adrian Hunter , linux-mm@kvack.org, Chris Mason , netdev@vger.kernel.org, Andreas Dilger , linux-xfs@vger.kernel.org, Eric Paris , linux-f2fs-devel@lists.sourceforge.net, linux-afs@lists.infradead.org, Stephen Smalley , Mike Marshall , devel@driverdev.osuosl.org, linux-cifs@vger.kernel.org, Paul Moore , Sage Weil , "Darrick J. Wong" , Richard Weinberger , Mark Fasheh , linux-unionfs@vger.kernel.org, Hugh Dickins , James Morris , cluster-devel@redhat.com, Joseph Qi , Vyacheslav Dubeyko , Casey Schaufler , v9fs-developer@lists.sourceforge.net, Ilya Dryomov , linux-ext4@vger.kernel.org, kernel-team@android.com, devel@lists.orangefs.org, Serge Hallyn , Eric Van Hensbergen , ecryptfs@vger.kernel.org, linux-erofs@lists.ozlabs.org, Josef Bacik , reiserfs-devel@vger.kernel.org, Bob Peterson , Joel Becker , Anna Schumaker , David Sterba , Jaegeuk Kim , ceph-devel@vger.kernel.org, selinux@vger.kernel.org, Trond Myklebust , Andreas Gruenbacher , David Howells , linux-nfs@vger.kernel.org, Theodore Ts'o , linux-fsdevel@vger.kernel.org, Artem Bityutskiy , Mathieu Malaterre , Greg Kroah-Hartman , Miklos Szeredi , Jeff Layton , linux-kernel@vger.kernel.org, stable@vger.kernel.org, Tyler Hicks , Steve French , Ernesto =?iso-8859-1?Q?A=2E_Fern=E1ndez?= , linux-btrfs@vger.kernel.org, linux-security-module@vger.kernel.org, Jan Kara , Tejun Heo , linux-mtd@lists.infradead.org, Andrew Morton , David Woodhouse , "David S. Miller" , ocfs2-devel@oss.oracle.com, Alexander Viro Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: linux-f2fs-devel-bounces@lists.sourceforge.net On Tue 13-08-19 07:55:06, Mark Salyzyn wrote: ... > diff --git a/fs/xattr.c b/fs/xattr.c > index 90dd78f0eb27..71f887518d6f 100644 > --- a/fs/xattr.c > +++ b/fs/xattr.c ... > ssize_t > __vfs_getxattr(struct dentry *dentry, struct inode *inode, const char *name, > - void *value, size_t size) > + void *value, size_t size, int flags) > { > const struct xattr_handler *handler; > - > - handler = xattr_resolve_name(inode, &name); > - if (IS_ERR(handler)) > - return PTR_ERR(handler); > - if (!handler->get) > - return -EOPNOTSUPP; > - return handler->get(handler, dentry, inode, name, value, size); > -} > -EXPORT_SYMBOL(__vfs_getxattr); > - > -ssize_t > -vfs_getxattr(struct dentry *dentry, const char *name, void *value, size_t size) > -{ > - struct inode *inode = dentry->d_inode; > int error; > > + if (flags & XATTR_NOSECURITY) > + goto nolsm; Hum, is it OK for XATTR_NOSECURITY to skip even the xattr_permission() check? I understand that for reads of security xattrs it actually does not matter in practice but conceptually that seems wrong to me as XATTR_NOSECURITY is supposed to skip just security-module checks to avoid recursion AFAIU. > diff --git a/include/uapi/linux/xattr.h b/include/uapi/linux/xattr.h > index c1395b5bd432..1216d777d210 100644 > --- a/include/uapi/linux/xattr.h > +++ b/include/uapi/linux/xattr.h > @@ -17,8 +17,9 @@ > #if __UAPI_DEF_XATTR > #define __USE_KERNEL_XATTR_DEFS > > -#define XATTR_CREATE 0x1 /* set value, fail if attr already exists */ > -#define XATTR_REPLACE 0x2 /* set value, fail if attr does not exist */ > +#define XATTR_CREATE 0x1 /* set value, fail if attr already exists */ > +#define XATTR_REPLACE 0x2 /* set value, fail if attr does not exist */ > +#define XATTR_NOSECURITY 0x4 /* get value, do not involve security check */ > #endif It seems confusing to export XATTR_NOSECURITY definition to userspace when that is kernel-internal flag. I'd just define it in include/linux/xattr.h somewhere from the top of flags space (like 0x40000000). Otherwise the patch looks OK to me (cannot really comment on the security module aspect of this whole thing though). Honza -- Jan Kara SUSE Labs, CR _______________________________________________ Linux-f2fs-devel mailing list Linux-f2fs-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel