From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Theodore Ts'o" Subject: Re: [PATCH v4 10/16] fs-verity: implement FS_IOC_ENABLE_VERITY ioctl Date: Sat, 15 Jun 2019 11:08:21 -0400 Message-ID: <20190615150821.GK6142@mit.edu> References: <20190606155205.2872-1-ebiggers@kernel.org> <20190606155205.2872-11-ebiggers@kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from [172.30.20.202] (helo=mx.sourceforge.net) by sfs-ml-2.v29.lw.sourceforge.com with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.90_1) (envelope-from ) id 1hcAIE-00087n-Tl for linux-f2fs-devel@lists.sourceforge.net; Sat, 15 Jun 2019 15:08:34 +0000 Received: from outgoing-auth-1.mit.edu ([18.9.28.11] helo=outgoing.mit.edu) by sfi-mx-3.v28.lw.sourceforge.com with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.90_1) id 1hcAID-00FWTQ-LT for linux-f2fs-devel@lists.sourceforge.net; Sat, 15 Jun 2019 15:08:35 +0000 Content-Disposition: inline In-Reply-To: <20190606155205.2872-11-ebiggers@kernel.org> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linux-f2fs-devel-bounces@lists.sourceforge.net To: Eric Biggers Cc: "Darrick J . Wong" , linux-api@vger.kernel.org, Dave Chinner , linux-f2fs-devel@lists.sourceforge.net, linux-fscrypt@vger.kernel.org, linux-fsdevel@vger.kernel.org, Jaegeuk Kim , linux-integrity@vger.kernel.org, linux-ext4@vger.kernel.org, Linus Torvalds , Christoph Hellwig , Victor Hsieh On Thu, Jun 06, 2019 at 08:51:59AM -0700, Eric Biggers wrote: > From: Eric Biggers > > Add a function for filesystems to call to implement the > FS_IOC_ENABLE_VERITY ioctl. This ioctl enables fs-verity on a file. > > See the "FS_IOC_ENABLE_VERITY" section of > Documentation/filesystems/fsverity.rst for the documentation. > > Signed-off-by: Eric Biggers > diff --git a/fs/verity/enable.c b/fs/verity/enable.c > new file mode 100644 > index 000000000000..7e7ef9d3c376 > --- /dev/null > +++ b/fs/verity/enable.c > + /* Tell the filesystem to finish enabling verity on the file */ > + err = vops->end_enable_verity(filp, desc, desc_size, params.tree_size); > + if (err) { > + fsverity_err(inode, "%ps() failed with err %d", > + vops->end_enable_verity, err); > + fsverity_free_info(vi); > + } else { > + /* Successfully enabled verity */ > + > + WARN_ON(!IS_VERITY(inode)); > + > + /* > + * Readers can start using ->i_verity_info immediately, so it > + * can't be rolled back once set. So don't set it until just > + * after the filesystem has successfully enabled verity. > + */ > + fsverity_set_info(inode, vi); > + } If end_enable_Verity() retuns success, and IS_VERITY is not set, I would think that we should report the error via fsverity_err() and return an error to userspace, and *not* call fsverity_set_info(). I don't think the stack trace printed by WARN_ON is going to very interesting, since the call path which gets us to enable_verity() is not going to be surprising. > + > + if (inode->i_size <= 0) { > + err = -EINVAL; > + goto out_unlock; > + } How hard would it be to support fsverity for zero-length files? There would be no Merkle tree, but there still would be an fsverity header file on which we can calculate a checksum for the digital signature. - Ted 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=-8.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_MUTT autolearn=ham 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 F1984C31E50 for ; Sat, 15 Jun 2019 15:08:36 +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 BF8BE20866; Sat, 15 Jun 2019 15:08:36 +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="d4jsq7Wz"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=sf.net header.i=@sf.net header.b="Sk/94Rxa" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BF8BE20866 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=mit.edu 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-2.v29.lw.sourceforge.com) by sfs-ml-2.v29.lw.sourceforge.com with esmtp (Exim 4.90_1) (envelope-from ) id 1hcAIG-00087u-0U; Sat, 15 Jun 2019 15:08:36 +0000 Received: from [172.30.20.202] (helo=mx.sourceforge.net) by sfs-ml-2.v29.lw.sourceforge.com with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.90_1) (envelope-from ) id 1hcAIE-00087n-Tl for linux-f2fs-devel@lists.sourceforge.net; Sat, 15 Jun 2019 15:08:34 +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=i9lqEJFTGPJLQh+Jx5UxSLe4/u0iv1+ABKGOLFQY+O4=; b=d4jsq7WzHevSeEMsq11Ictmxdq CncZjjkXc1CkSlds/AM6/BvC6Ch971O3CFHCOmdM8+OeLaYj2WWrNRL5LCuaRZlBts4a2FPj782lm dV+133xP0L6FeNk38M9FQ/MTmqtiJPbYF73HIozJQgRHFVyIfC+4ZRvJhpVa7gHeepp0=; 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=i9lqEJFTGPJLQh+Jx5UxSLe4/u0iv1+ABKGOLFQY+O4=; b=Sk/94Rxatg9m9HResi39BiIgtx /D/L47IWnL0LZE/i5z5Ia2l7mx7QxdLSfWbuceAbr6jHlZwT+RnetRPD84n5r/eh5sS0SLyRpACVj U1fsZzRv8gB9lEClUUBn21tg6Lwo1R1Wlq0feAdhKYoGrQnr6jWbEKiEE09WxknSomWY=; Received: from outgoing-auth-1.mit.edu ([18.9.28.11] helo=outgoing.mit.edu) by sfi-mx-3.v28.lw.sourceforge.com with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.90_1) id 1hcAID-00FWTQ-LT for linux-f2fs-devel@lists.sourceforge.net; Sat, 15 Jun 2019 15:08:35 +0000 Received: from callcc.thunk.org (rrcs-74-87-88-165.west.biz.rr.com [74.87.88.165]) (authenticated bits=0) (User authenticated as tytso@ATHENA.MIT.EDU) by outgoing.mit.edu (8.14.7/8.12.4) with ESMTP id x5FF8Lhv005865 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Sat, 15 Jun 2019 11:08:22 -0400 Received: by callcc.thunk.org (Postfix, from userid 15806) id 2BC23420484; Sat, 15 Jun 2019 11:08:21 -0400 (EDT) Date: Sat, 15 Jun 2019 11:08:21 -0400 From: "Theodore Ts'o" To: Eric Biggers Message-ID: <20190615150821.GK6142@mit.edu> References: <20190606155205.2872-1-ebiggers@kernel.org> <20190606155205.2872-11-ebiggers@kernel.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20190606155205.2872-11-ebiggers@kernel.org> User-Agent: Mutt/1.10.1 (2018-07-13) X-Headers-End: 1hcAID-00FWTQ-LT Subject: Re: [f2fs-dev] [PATCH v4 10/16] fs-verity: implement FS_IOC_ENABLE_VERITY ioctl 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: "Darrick J . Wong" , linux-api@vger.kernel.org, Dave Chinner , linux-f2fs-devel@lists.sourceforge.net, linux-fscrypt@vger.kernel.org, linux-fsdevel@vger.kernel.org, Jaegeuk Kim , linux-integrity@vger.kernel.org, linux-ext4@vger.kernel.org, Linus Torvalds , Christoph Hellwig , Victor Hsieh Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Errors-To: linux-f2fs-devel-bounces@lists.sourceforge.net Message-ID: <20190615150821.DD0LPqeRazcKYn68B_4JVPHHEVW4VHKi3VdPaPyVbdw@z> On Thu, Jun 06, 2019 at 08:51:59AM -0700, Eric Biggers wrote: > From: Eric Biggers > > Add a function for filesystems to call to implement the > FS_IOC_ENABLE_VERITY ioctl. This ioctl enables fs-verity on a file. > > See the "FS_IOC_ENABLE_VERITY" section of > Documentation/filesystems/fsverity.rst for the documentation. > > Signed-off-by: Eric Biggers > diff --git a/fs/verity/enable.c b/fs/verity/enable.c > new file mode 100644 > index 000000000000..7e7ef9d3c376 > --- /dev/null > +++ b/fs/verity/enable.c > + /* Tell the filesystem to finish enabling verity on the file */ > + err = vops->end_enable_verity(filp, desc, desc_size, params.tree_size); > + if (err) { > + fsverity_err(inode, "%ps() failed with err %d", > + vops->end_enable_verity, err); > + fsverity_free_info(vi); > + } else { > + /* Successfully enabled verity */ > + > + WARN_ON(!IS_VERITY(inode)); > + > + /* > + * Readers can start using ->i_verity_info immediately, so it > + * can't be rolled back once set. So don't set it until just > + * after the filesystem has successfully enabled verity. > + */ > + fsverity_set_info(inode, vi); > + } If end_enable_Verity() retuns success, and IS_VERITY is not set, I would think that we should report the error via fsverity_err() and return an error to userspace, and *not* call fsverity_set_info(). I don't think the stack trace printed by WARN_ON is going to very interesting, since the call path which gets us to enable_verity() is not going to be surprising. > + > + if (inode->i_size <= 0) { > + err = -EINVAL; > + goto out_unlock; > + } How hard would it be to support fsverity for zero-length files? There would be no Merkle tree, but there still would be an fsverity header file on which we can calculate a checksum for the digital signature. - Ted _______________________________________________ Linux-f2fs-devel mailing list Linux-f2fs-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel