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=-6.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FSL_HELO_FAKE,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,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 258BBC04AA8 for ; Tue, 30 Apr 2019 16:51:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F006F21670 for ; Tue, 30 Apr 2019 16:51:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1556643080; bh=3A7w+7LZPtm+9FWKjAgeHNtIX9e4JIDaC+A4dd4ARQ8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=p5stuL7qOilp0xHze/7OxXADYBthe9AMir94xoIkyed01NnVV5HgVwX/UVOhsEeKy Oku3Qhc2J1ACCd0baSpXTZpC842Bf8MuPRWeXmOZTmciiOBmQv5A2VhNT6NbmUDAKT d6MOc1/nXdL48GwsDSevXtobI6YXA/QLojt4UPsM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726061AbfD3QvS (ORCPT ); Tue, 30 Apr 2019 12:51:18 -0400 Received: from mail.kernel.org ([198.145.29.99]:37252 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725942AbfD3QvS (ORCPT ); Tue, 30 Apr 2019 12:51:18 -0400 Received: from gmail.com (unknown [104.132.1.77]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 52DF92147A; Tue, 30 Apr 2019 16:51:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1556643077; bh=3A7w+7LZPtm+9FWKjAgeHNtIX9e4JIDaC+A4dd4ARQ8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Ac5F7t0j6x24hq3IoaAVr5vKg3sOed28k6SV2U+v0kOOicvbQ9Bo+Z8sR/VlBjaY4 Wt7nXL7vV9xnSg1i4wF3IeXYBaH/rsVuS3+KuNG778bEP5XGmZt+kTV/rN1VaGl+Gr MGfC0vxfwf3QR6eLBLVcoQPWxrmliOTjA5P2PDsM= Date: Tue, 30 Apr 2019 09:51:15 -0700 From: Eric Biggers To: Chandan Rajendra Cc: linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-fscrypt@vger.kernel.org, tytso@mit.edu, adilger.kernel@dilger.ca, jaegeuk@kernel.org, yuchao0@huawei.com, hch@infradead.org Subject: Re: [PATCH V2 12/13] fscrypt_zeroout_range: Encrypt all zeroed out blocks of a page Message-ID: <20190430165114.GA48973@gmail.com> References: <20190428043121.30925-1-chandan@linux.ibm.com> <20190428043121.30925-13-chandan@linux.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190428043121.30925-13-chandan@linux.ibm.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Sun, Apr 28, 2019 at 10:01:20AM +0530, Chandan Rajendra wrote: > For subpage-sized blocks, this commit adds code to encrypt all zeroed > out blocks mapped by a page. > > Signed-off-by: Chandan Rajendra > --- > fs/crypto/bio.c | 40 ++++++++++++++++++---------------------- > 1 file changed, 18 insertions(+), 22 deletions(-) > > diff --git a/fs/crypto/bio.c b/fs/crypto/bio.c > index 856f4694902d..46dd2ec50c7d 100644 > --- a/fs/crypto/bio.c > +++ b/fs/crypto/bio.c > @@ -108,29 +108,23 @@ EXPORT_SYMBOL(fscrypt_pullback_bio_page); > int fscrypt_zeroout_range(const struct inode *inode, pgoff_t lblk, > sector_t pblk, unsigned int len) > { > - struct fscrypt_ctx *ctx; > struct page *ciphertext_page = NULL; > struct bio *bio; > + u64 total_bytes, page_bytes; page_bytes should be 'unsigned int', since it's <= PAGE_SIZE. > int ret, err = 0; > > - BUG_ON(inode->i_sb->s_blocksize != PAGE_SIZE); > - > - ctx = fscrypt_get_ctx(inode, GFP_NOFS); > - if (IS_ERR(ctx)) > - return PTR_ERR(ctx); > + total_bytes = len << inode->i_blkbits; Should cast len to 'u64' here, in case it's greater than UINT_MAX / blocksize. > > - ciphertext_page = fscrypt_alloc_bounce_page(ctx, GFP_NOWAIT); > - if (IS_ERR(ciphertext_page)) { > - err = PTR_ERR(ciphertext_page); > - goto errout; > - } > + while (total_bytes) { > + page_bytes = min_t(u64, total_bytes, PAGE_SIZE); > > - while (len--) { > - err = fscrypt_do_page_crypto(inode, FS_ENCRYPT, lblk, > - ZERO_PAGE(0), ciphertext_page, > - PAGE_SIZE, 0, GFP_NOFS); > - if (err) > + ciphertext_page = fscrypt_encrypt_page(inode, ZERO_PAGE(0), > + page_bytes, 0, lblk, GFP_NOFS); > + if (IS_ERR(ciphertext_page)) { > + err = PTR_ERR(ciphertext_page); > + ciphertext_page = NULL; > goto errout; > + } 'ciphertext_page' is leaked after each loop iteration. Did you mean to free it, or did you mean to reuse it for subsequent iterations? > > bio = bio_alloc(GFP_NOWAIT, 1); > if (!bio) { > @@ -141,9 +135,8 @@ int fscrypt_zeroout_range(const struct inode *inode, pgoff_t lblk, > bio->bi_iter.bi_sector = > pblk << (inode->i_sb->s_blocksize_bits - 9); This line uses ->s_blocksize_bits, but your new code uses ->i_blkbits. AFAIK they'll always be the same, but please pick one or the other to use. > bio_set_op_attrs(bio, REQ_OP_WRITE, 0); > - ret = bio_add_page(bio, ciphertext_page, > - inode->i_sb->s_blocksize, 0); > - if (ret != inode->i_sb->s_blocksize) { > + ret = bio_add_page(bio, ciphertext_page, page_bytes, 0); > + if (ret != page_bytes) { > /* should never happen! */ > WARN_ON(1); > bio_put(bio); > @@ -156,12 +149,15 @@ int fscrypt_zeroout_range(const struct inode *inode, pgoff_t lblk, > bio_put(bio); > if (err) > goto errout; > - lblk++; > - pblk++; > + > + lblk += page_bytes >> inode->i_blkbits; > + pblk += page_bytes >> inode->i_blkbits; > + total_bytes -= page_bytes; > } > err = 0; > errout: > - fscrypt_release_ctx(ctx); > + if (!IS_ERR_OR_NULL(ciphertext_page)) > + fscrypt_restore_control_page(ciphertext_page); > return err; > } > EXPORT_SYMBOL(fscrypt_zeroout_range); > -- > 2.19.1 >