From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F217CC433E5 for ; Wed, 17 Jun 2020 23:12:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D086720734 for ; Wed, 17 Jun 2020 23:12:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726946AbgFQXMS (ORCPT ); Wed, 17 Jun 2020 19:12:18 -0400 Received: from smtprelay0191.hostedemail.com ([216.40.44.191]:41454 "EHLO smtprelay.hostedemail.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726761AbgFQXMS (ORCPT ); Wed, 17 Jun 2020 19:12:18 -0400 Received: from filter.hostedemail.com (clb03-v110.bra.tucows.net [216.40.38.60]) by smtprelay07.hostedemail.com (Postfix) with ESMTP id C6BF8181D330D; Wed, 17 Jun 2020 23:12:13 +0000 (UTC) X-Session-Marker: 6A6F6540706572636865732E636F6D X-HE-Tag: anger66_3706ec726e0b X-Filterd-Recvd-Size: 3931 Received: from XPS-9350.home (unknown [47.151.133.149]) (Authenticated sender: joe@perches.com) by omf11.hostedemail.com (Postfix) with ESMTPA; Wed, 17 Jun 2020 23:12:07 +0000 (UTC) Message-ID: <38c5745d14cff75fe264a3bc61d19fd837baf7ad.camel@perches.com> Subject: Re: [PATCH v4 0/3] mm, treewide: Rename kzfree() to kfree_sensitive() From: Joe Perches To: Denis Efremov , Waiman Long , Andrew Morton , David Howells , Jarkko Sakkinen , James Morris , "Serge E. Hallyn" , Linus Torvalds , Matthew Wilcox , David Rientjes Cc: Michal Hocko , Johannes Weiner , Dan Carpenter , David Sterba , "Jason A . Donenfeld" , linux-mm@kvack.org, keyrings@vger.kernel.org, linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org, linux-pm@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-amlogic@lists.infradead.org, linux-mediatek@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, linux-ppp@vger.kernel.org, wireguard@lists.zx2c4.com, linux-wireless@vger.kernel.org, devel@driverdev.osuosl.org, linux-scsi@vger.kernel.org, target-devel@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-cifs@vger.kernel.org, linux-fscrypt@vger.kernel.org, ecryptfs@vger.kernel.org, kasan-dev@googlegroups.com, linux-bluetooth@vger.kernel.org, linux-wpan@vger.kernel.org, linux-sctp@vger.kernel.org, linux-nfs@vger.kernel.org, tipc-discussion@lists.sourceforge.net, linux-security-module@vger.kernel.org, linux-integrity@vger.kernel.org Date: Wed, 17 Jun 2020 16:12:06 -0700 In-Reply-To: <17e4fede-bab0-d93c-6964-69decc889d7d@ispras.ru> References: <20200616015718.7812-1-longman@redhat.com> <17e4fede-bab0-d93c-6964-69decc889d7d@ispras.ru> Content-Type: text/plain; charset="ISO-8859-1" User-Agent: Evolution 3.36.2-0ubuntu1 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-fscrypt-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fscrypt@vger.kernel.org On Thu, 2020-06-18 at 00:31 +0300, Denis Efremov wrote: > > On 6/16/20 9:53 PM, Joe Perches wrote: > > On Mon, 2020-06-15 at 21:57 -0400, Waiman Long wrote: > > > v4: > > > - Break out the memzero_explicit() change as suggested by Dan Carpenter > > > so that it can be backported to stable. > > > - Drop the "crypto: Remove unnecessary memzero_explicit()" patch for > > > now as there can be a bit more discussion on what is best. It will be > > > introduced as a separate patch later on after this one is merged. > > > > To this larger audience and last week without reply: > > https://lore.kernel.org/lkml/573b3fbd5927c643920e1364230c296b23e7584d.camel@perches.com/ > > > > Are there _any_ fastpath uses of kfree or vfree? > > > > Many patches have been posted recently to fix mispairings > > of specific types of alloc and free functions. > > I've prepared a coccinelle script to highlight these mispairings in a function > a couple of days ago: https://lkml.org/lkml/2020/6/5/953 > I've listed all the fixes in the commit message. > > Not so many mispairings actually, and most of them are harmless like: > kmalloc(E) -> kvfree(E) > > However, coccinelle script can't detect cross-functions mispairings, i.e. > allocation in one function, free in another funtion. Hey Denis, thanks for those patches. If possible, it's probably better to not require these pairings and use a single standard kfree/free function. Given the existing ifs in kfree in slab/slob/slub, it seems likely that adding a few more wouldn't have much impact.