From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dmitry Torokhov Subject: Re: [PATCH] Input: cyttsp4 - Fix error on calculating memory size passed to krealloc. Date: Fri, 3 Nov 2017 12:09:39 -0700 Message-ID: <20171103190939.eibdhyg4kqapzdkn@dtor-ws> References: <1509477598-7010-1-git-send-email-vince.k.kim@gmail.com> <20171102235451.wc7l22vpuxr4n32c@dtor-ws> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mail-io0-f195.google.com ([209.85.223.195]:44319 "EHLO mail-io0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751957AbdKCTJn (ORCPT ); Fri, 3 Nov 2017 15:09:43 -0400 Content-Disposition: inline In-Reply-To: Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: Vince Kim Cc: Ferruh Yigit , linux-input@vger.kernel.org, linux-kernel@vger.kernel.org On Thu, Nov 02, 2017 at 08:49:35PM -0700, Vince Kim wrote: > Hello Dmitry, > > I attached patch with signed-off-by. *sigh* did you try compile that? + if (si->si_ofs.test_ofs <= si->si_ofs.cydata_ofs) + dev_err(cd->dev, "%s: invalid offset test_ofs:%zd, cydata_ofs:%zd \n", __func__, si->si_ofs.test_ofs, si->si_ofs.cydata_ofs); + return -EINVAL; + } + There is an opening curly brace missing. Same goes for the other 3 chunks of the patch. I fixed it up. > If you need a patch inline, please let me know. The inline patch formatted according to Documentation/SubmittingPatches is preferred, but I'd settle on something that compiles. Thanks. > > Thanks, > Vince > > > > > On Thu, Nov 2, 2017 at 4:54 PM, Dmitry Torokhov > wrote: > > > Hi Vince, > > > > On Wed, Nov 01, 2017 at 09:13:58PM -0700, Vince Kim wrote: > > > It looks patch send to the maintainer rejected. > > > > > > > I can take the patch, but I need your signed-off-by please. > > > > > Can anyone take a look? > > > > > > > > > > > > *==============================* > > > > > > *Delivery has failed to these recipients or groups:* > > > > > > Ferruh Yigit (fery@cypress.com) > > > Your message wasn't delivered due to a permission or security issue. It > > may > > > have been rejected by a moderator, the address may only accept e-mail > > from > > > certain senders, or another restriction may be preventing delivery. > > > *==============================* > > > > > > On Tue, Oct 31, 2017 at 12:19 PM, Vince Kim > > wrote: > > > > > > > There are several places to perform subtraction to calculate buffer > > > > size such as: > > > > > > > > si->si_ofs.cydata_size = si->si_ofs.test_ofs - si->si_ofs.cydata_ofs; > > > > ... > > > > p = krealloc(si->si_ptrs.cydata, si->si_ofs.cydata_size, GFP_KERNEL); > > > > > > > > Actually, data types of above variables during subtraction are size_t, > > so > > > > it is > > > > unsigned. That means if second operand(si->si_ofs.cydata_ofs) is > > > > greater than the first operand(si->si_ofs.test_ofs), then resulting > > > > si->si_ofs.cydata_size could result in an unsigned integer wrap which > > is > > > > not desiarable. > > > > > > > > The properway to correct this problem is to perform a test of both > > > > operands to avoid having unsigned wrap. > > > > --- > > > > drivers/input/touchscreen/cyttsp4_core.c | 20 ++++++++++++++++++++ > > > > 1 file changed, 20 insertions(+) > > > > > > > > diff --git a/drivers/input/touchscreen/cyttsp4_core.c > > > > b/drivers/input/touchscreen/cyttsp4_core.c > > > > index beaf61c..eecc7f1 100644 > > > > --- a/drivers/input/touchscreen/cyttsp4_core.c > > > > +++ b/drivers/input/touchscreen/cyttsp4_core.c > > > > @@ -201,6 +201,11 @@ static int cyttsp4_si_get_cydata(struct cyttsp4 > > *cd) > > > > void *p; > > > > int rc; > > > > > > > > + if (si->si_ofs.test_ofs <= si->si_ofs.cydata_ofs) > > > > + dev_err(cd->dev, "%s: invalid offset test_ofs:%zd, > > > > cydata_ofs:%zd \n", __func__, si->si_ofs.test_ofs, > > si->si_ofs.cydata_ofs); > > > > + return -EINVAL; > > > > + } > > > > + > > > > si->si_ofs.cydata_size = si->si_ofs.test_ofs - > > > > si->si_ofs.cydata_ofs; > > > > dev_dbg(cd->dev, "%s: cydata size: %zd\n", __func__, > > > > si->si_ofs.cydata_size); > > > > @@ -270,6 +275,11 @@ static int cyttsp4_si_get_test_data(struct > > cyttsp4 > > > > *cd) > > > > void *p; > > > > int rc; > > > > > > > > + if (si->si_ofs.pcfg_ofs <= si->si_ofs.test_ofs) > > > > + dev_err(cd->dev, "%s: invalid offset pcfg_ofs:%zd, > > > > test_ofs:%zd \n", __func__, si->si_ofs.pcfg_ofs, si->si_ofs.test_ofs); > > > > + return -EINVAL; > > > > + } > > > > + > > > > si->si_ofs.test_size = si->si_ofs.pcfg_ofs - > > si->si_ofs.test_ofs; > > > > > > > > p = krealloc(si->si_ptrs.test, si->si_ofs.test_size, > > GFP_KERNEL); > > > > @@ -321,6 +331,11 @@ static int cyttsp4_si_get_pcfg_data(struct > > cyttsp4 > > > > *cd) > > > > void *p; > > > > int rc; > > > > > > > > + if (si->si_ofs.opcfg_ofs <= si->si_ofs.pcfg_ofs) > > > > + dev_err(cd->dev, "%s: invalid offset opcfg_ofs:%zd, > > > > pcfg_ofs:%zd \n", __func__, si->si_ofs.opcfg_ofs, si->si_ofs.pcfg_ofs); > > > > + return -EINVAL; > > > > + } > > > > + > > > > si->si_ofs.pcfg_size = si->si_ofs.opcfg_ofs - > > si->si_ofs.pcfg_ofs; > > > > > > > > p = krealloc(si->si_ptrs.pcfg, si->si_ofs.pcfg_size, > > GFP_KERNEL); > > > > @@ -367,6 +382,11 @@ static int cyttsp4_si_get_opcfg_data(struct > > cyttsp4 > > > > *cd) > > > > void *p; > > > > int rc; > > > > > > > > + if (si->si_ofs.ddata_ofs <= si->si_ofs.opcfg_ofs) > > > > + dev_err(cd->dev, "%s: invalid offset ddata_ofs:%zd, > > > > opcfg_ofs:%zd \n", __func__, si->si_ofs.ddata_ofs, > > si->si_ofs.opcfg_ofs); > > > > + return -EINVAL; > > > > + } > > > > + > > > > si->si_ofs.opcfg_size = si->si_ofs.ddata_ofs - > > > > si->si_ofs.opcfg_ofs; > > > > > > > > p = krealloc(si->si_ptrs.opcfg, si->si_ofs.opcfg_size, > > GFP_KERNEL); > > > > -- > > > > 2.7.4 > > > > > > > > > > > > -- > > Dmitry > > -- Dmitry