Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756217Ab0H3R2P (ORCPT ); Mon, 30 Aug 2010 13:28:15 -0400 Received: from hera.kernel.org ([140.211.167.34]:43074 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755539Ab0H3R2M (ORCPT ); Mon, 30 Aug 2010 13:28:12 -0400 Message-ID: <4C7BEA30.1090000@kernel.org> Date: Mon, 30 Aug 2010 19:28:16 +0200 From: Tejun Heo User-Agent: Mozilla/5.0 (X11; U; Linux i686 (x86_64); en-US; rv:1.9.2.8) Gecko/20100802 Thunderbird/3.1.2 MIME-Version: 1.0 To: Jeffrey Carlyle CC: OLUSANYA SOYANNWO , linux-kernel@vger.kernel.org, Hu Tao , jaxboe@fusionio.com, torvalds@osdl.org Subject: Re: [PATCH v6] scatterlist: prevent invalid free when alloc fails References: <4C7BD8BE.7050600@kernel.org> <20100830165022.96032603843@il93ubuntu.localdomain> In-Reply-To: <20100830165022.96032603843@il93ubuntu.localdomain> X-Enigmail-Version: 1.1.1 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.3 (hera.kernel.org [127.0.0.1]); Mon, 30 Aug 2010 17:28:07 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 893 Lines: 23 On 08/30/2010 06:19 PM, Jeffrey Carlyle wrote: > When alloc fails, free_table is being called. Depending on the number of > bytes requested, we determine if we are going to call _get_free_page() > or kmalloc(). When alloc fails, our math is wrong (due to sg_size - 1), > and the last buffer is wrongfully assumed to have been allocated by > kmalloc. Hence, kfree gets called and a panic occurs. > > Signed-off-by: Jeffrey Carlyle > Signed-off-by: Olusanya Soyannwo > Cc: Tejun Heo > Cc: Jens Axboe Acked-by: Tejun Heo Thanks. :-) -- tejun -- 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/