Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757372Ab2BIMm4 (ORCPT ); Thu, 9 Feb 2012 07:42:56 -0500 Received: from casper.infradead.org ([85.118.1.10]:41224 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753785Ab2BIMmz (ORCPT ); Thu, 9 Feb 2012 07:42:55 -0500 Message-ID: <4F33BF02.7060906@kernel.dk> Date: Thu, 09 Feb 2012 13:41:38 +0100 From: Jens Axboe MIME-Version: 1.0 To: Andrew Morton CC: Dan Carpenter , linux-kernel@vger.kernel.org Subject: Re: integer overflows in kernel/relay.c References: <20120207141155.GA16184@elgon.mountain> <4F323388.7040902@kernel.dk> <20120208142513.4db2493a.akpm@linux-foundation.org> In-Reply-To: <20120208142513.4db2493a.akpm@linux-foundation.org> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1435 Lines: 41 On 02/08/2012 11:25 PM, Andrew Morton wrote: > On Wed, 08 Feb 2012 09:34:16 +0100 > Jens Axboe wrote: > >> On 02/07/2012 03:11 PM, Dan Carpenter wrote: >>> My static checker is warning about integer overflows in kernel/relay.c >>> >>> relay_create_buf() >>> 170 >>> 171 buf->padding = kmalloc(chan->n_subbufs * sizeof(size_t *), GFP_KERNEL); >>> ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ >>> This can only overflow on 32bit systems. >> >> Correct > > This is a relatively common problem. Converting a kzalloc() call to > kcalloc() fixes it. But we do not have a non-zeroing version of > kcalloc(). > > Please, someone complete this patch and send it to me! > > > --- a/include/linux/slab.h~a > +++ a/include/linux/slab.h > @@ -240,11 +240,16 @@ size_t ksize(const void *); > * for general use, and so are not documented here. For a full list of > * potential flags, always refer to linux/gfp.h. > */ > -static inline void *kcalloc(size_t n, size_t size, gfp_t flags) > +static inline void *wtf_do_i_call_this(size_t n, size_t size, gfp_t flags) kzcalloc()? Either that, or long_and_verbose(). -- Jens Axboe -- 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/