Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932470AbXAIWpV (ORCPT ); Tue, 9 Jan 2007 17:45:21 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932484AbXAIWpV (ORCPT ); Tue, 9 Jan 2007 17:45:21 -0500 Received: from smtp.osdl.org ([65.172.181.24]:49785 "EHLO smtp.osdl.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932470AbXAIWpU (ORCPT ); Tue, 9 Jan 2007 17:45:20 -0500 Date: Tue, 9 Jan 2007 14:42:03 -0800 From: Andrew Morton To: Michael Halcrow Cc: linux-kernel@vger.kernel.org, tshighla@us.ibm.com, theotso@us.ibm.com Subject: Re: [PATCH 3/3] eCryptfs: Encrypted passthrough Message-Id: <20070109144203.ce1ed092.akpm@osdl.org> In-Reply-To: <20070109222337.GF16578@us.ibm.com> References: <20070109222107.GC16578@us.ibm.com> <20070109222337.GF16578@us.ibm.com> X-Mailer: Sylpheed version 2.2.7 (GTK+ 2.8.6; i686-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1189 Lines: 38 On Tue, 9 Jan 2007 16:23:37 -0600 Michael Halcrow wrote: > + page_virt = (char *)kmap(page); Do we _have_ to use kmap here? It's slow and theoretically deadlocky. kmap_atomic() is much preferred. Can the other kmap() calls in ecryptfs be converted? We'd actually like to remove kmap() one day. Not much chance of that, but it's an objective. > + if (!page_virt) { > + rc = -ENOMEM; > + printk(KERN_ERR "Error mapping page\n"); > + goto out; > + } > + memset(page_virt, 0, PAGE_CACHE_SIZE); > + if (page->index == 0) { > + rc = ecryptfs_read_xattr_region( > + page_virt, file->f_path.dentry); Are we assured that ecryptfs_read_xattr_region() cannot overrun the page? > + set_header_info(page_virt, crypt_stat); > + } The kernel must always run flush_dcache_page() after modifying a pagecache page by hand. Please review all of ecryptfs for this. > + kunmap(page); - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/