From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Biggers Subject: Re: [PATCH V2 10/13] fscrypt_encrypt_page: Loop across all blocks mapped by a page range Date: Tue, 30 Apr 2019 10:11:35 -0700 Message-ID: <20190430171133.GC48973@gmail.com> References: <20190428043121.30925-1-chandan@linux.ibm.com> <20190428043121.30925-11-chandan@linux.ibm.com> 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 1hLWIB-0004Bz-FU for linux-f2fs-devel@lists.sourceforge.net; Tue, 30 Apr 2019 17:11:43 +0000 Received: from mail.kernel.org ([198.145.29.99]) by sfi-mx-4.v28.lw.sourceforge.com with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.90_1) id 1hLWIA-000p3z-9U for linux-f2fs-devel@lists.sourceforge.net; Tue, 30 Apr 2019 17:11:43 +0000 Content-Disposition: inline In-Reply-To: <20190428043121.30925-11-chandan@linux.ibm.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linux-f2fs-devel-bounces@lists.sourceforge.net To: Chandan Rajendra Cc: tytso@mit.edu, linux-f2fs-devel@lists.sourceforge.net, hch@infradead.org, linux-fscrypt@vger.kernel.org, adilger.kernel@dilger.ca, linux-fsdevel@vger.kernel.org, jaegeuk@kernel.org, linux-ext4@vger.kernel.org On Sun, Apr 28, 2019 at 10:01:18AM +0530, Chandan Rajendra wrote: > For subpage-sized blocks, this commit now encrypts all blocks mapped by > a page range. > > Signed-off-by: Chandan Rajendra > --- > fs/crypto/crypto.c | 37 +++++++++++++++++++++++++------------ > 1 file changed, 25 insertions(+), 12 deletions(-) > > diff --git a/fs/crypto/crypto.c b/fs/crypto/crypto.c > index 4f0d832cae71..2d65b431563f 100644 > --- a/fs/crypto/crypto.c > +++ b/fs/crypto/crypto.c > @@ -242,18 +242,26 @@ struct page *fscrypt_encrypt_page(const struct inode *inode, Need to update the function comment to clearly explain what this function actually does now. > { > struct fscrypt_ctx *ctx; > struct page *ciphertext_page = page; > + int i, page_nr_blks; > int err; > > BUG_ON(len % FS_CRYPTO_BLOCK_SIZE != 0); > Make a 'blocksize' variable so you don't have to keep calling i_blocksize(). Also, you need to check whether 'len' and 'offs' are filesystem-block-aligned, since the code now assumes it. const unsigned int blocksize = i_blocksize(inode); if (!IS_ALIGNED(len | offs, blocksize)) return -EINVAL; However, did you check whether that's always true for ubifs? It looks like it may expect to encrypt a prefix of a block, that is only padded to the next 16-byte boundary. > + page_nr_blks = len >> inode->i_blkbits; > + > if (inode->i_sb->s_cop->flags & FS_CFLG_OWN_PAGES) { > /* with inplace-encryption we just encrypt the page */ > - err = fscrypt_do_page_crypto(inode, FS_ENCRYPT, lblk_num, page, > - ciphertext_page, len, offs, > - gfp_flags); > - if (err) > - return ERR_PTR(err); > - > + for (i = 0; i < page_nr_blks; i++) { > + err = fscrypt_do_page_crypto(inode, FS_ENCRYPT, > + lblk_num, page, > + ciphertext_page, > + i_blocksize(inode), offs, > + gfp_flags); > + if (err) > + return ERR_PTR(err); > + ++lblk_num; > + offs += i_blocksize(inode); > + } > return ciphertext_page; > } > > @@ -269,12 +277,17 @@ struct page *fscrypt_encrypt_page(const struct inode *inode, > goto errout; > > ctx->control_page = page; > - err = fscrypt_do_page_crypto(inode, FS_ENCRYPT, lblk_num, > - page, ciphertext_page, len, offs, > - gfp_flags); > - if (err) { > - ciphertext_page = ERR_PTR(err); > - goto errout; > + > + for (i = 0; i < page_nr_blks; i++) { > + err = fscrypt_do_page_crypto(inode, FS_ENCRYPT, lblk_num, > + page, ciphertext_page, > + i_blocksize(inode), offs, gfp_flags); As I mentioned elsewhere, renaming fscrypt_do_page_crypto() to fscrypt_crypt_block() would make more sense now. > + if (err) { > + ciphertext_page = ERR_PTR(err); > + goto errout; > + } > + ++lblk_num; > + offs += i_blocksize(inode); > } > SetPagePrivate(ciphertext_page); > set_page_private(ciphertext_page, (unsigned long)ctx); > -- > 2.19.1 >