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=-12.9 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1, USER_IN_DEF_DKIM_WL autolearn=unavailable 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 12F44C2BBC7 for ; Tue, 14 Apr 2020 00:30:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DF74621655 for ; Tue, 14 Apr 2020 00:30:19 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="PMRE9MFB" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390495AbgDNAaR (ORCPT ); Mon, 13 Apr 2020 20:30:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47856 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390458AbgDNAaB (ORCPT ); Mon, 13 Apr 2020 20:30:01 -0400 Received: from mail-pf1-x441.google.com (mail-pf1-x441.google.com [IPv6:2607:f8b0:4864:20::441]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C5C9DC00860B for ; Mon, 13 Apr 2020 17:30:00 -0700 (PDT) Received: by mail-pf1-x441.google.com with SMTP id y25so3009959pfn.5 for ; Mon, 13 Apr 2020 17:30:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:from:to:cc:subject:in-reply-to:message-id:references :user-agent:mime-version; bh=GtP40NBc6K+wY7TevCqJVJVyGGxw6eyhk3x6njvRZbI=; b=PMRE9MFBjRNguCLZJxvQ0tC6cbj5HN/L0mNJHOjg1H5naWvyPaji8Uw6CjXqOQ2azW MhWs/LuNrHlvICFisvb7Cy6SJ3VKQrmiHJlokad5hGoOXcGXzDY3vorrrgpyAZrAVUDE dUN76VdbMCLvs9G10TRyVoj/R2uKEUPKhrkRhwWPh9Qq6Oj8zqhrDAXwnWHye+K8R3ym lDZQumSHVx6+RupP9U0o1EyjztcXPr7zTXefIIyzd+nYkxQBJg3bKkumuWN4k6N/hrZC eN210smaNX58gX6QVglgalvDGfi5xzWfnOSt7/cWPG1d3xQeaexIo7gZ03EO3NRYAH/8 2wUQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:in-reply-to:message-id :references:user-agent:mime-version; bh=GtP40NBc6K+wY7TevCqJVJVyGGxw6eyhk3x6njvRZbI=; b=cihokw/pOOTtleXqZx2qHXT06oTDUWTskvCu3SpWJP3dk8v6Y9gIG9CEn9QDBnK9cs +v6zT+fjU+8nxSd3FnsMjm3pMnjxdKVex+gopU/EWyGcaosAj6ekFAvm4Sthq0pfU434 IbebJJfHPjJEHqzRAuG9Y5Z5EzgzWD8jIprtl0ALii/CudDxt3Q096H47DO8bOvuw0F+ 9cRfhqldc0l9RKJr73WD2jK/8hbiC8NtLKJVLW7Uw83acrDPnhq3UJ6l9u5DEBJPGgrx QamZ10TJHZy2g6wu/i2R8EXJuZVtrycZ4sNoEEKmoENQq23btZ3Y/TULgwT675Mc9kHm el3A== X-Gm-Message-State: AGi0PuYFJng/QDhSE7pJMhNnjpDbyMKzG3E21VnOHxEThanhsWsjd0nw oSj9kP8W5D+FY9YF1NzQstLY8Q== X-Google-Smtp-Source: APiQypL5W5g7xmsU3GZXO1UecYYPwVLK1dPD412glciRM3pdZ8NSkRu/LjnNHn8Pg6Fxg4L/cgCpIw== X-Received: by 2002:a62:dd48:: with SMTP id w69mr10144721pff.86.1586824199909; Mon, 13 Apr 2020 17:29:59 -0700 (PDT) Received: from [2620:15c:17:3:3a5:23a7:5e32:4598] ([2620:15c:17:3:3a5:23a7:5e32:4598]) by smtp.gmail.com with ESMTPSA id g11sm10055136pjs.17.2020.04.13.17.29.58 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 13 Apr 2020 17:29:59 -0700 (PDT) Date: Mon, 13 Apr 2020 17:29:58 -0700 (PDT) From: David Rientjes X-X-Sender: rientjes@chino.kir.corp.google.com To: Waiman Long cc: Andrew Morton , David Howells , Jarkko Sakkinen , James Morris , "Serge E. Hallyn" , Linus Torvalds , Joe Perches , Matthew Wilcox , linux-mm@kvack.org, keyrings@vger.kernel.org, linux-kernel@vger.kernel.org, x86@kernel.org, linux-crypto@vger.kernel.org, linux-s390@vger.kernel.org, linux-pm@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, linux-amlogic@lists.infradead.org, linux-mediatek@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, intel-wired-lan@lists.osuosl.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, samba-technical@lists.samba.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, cocci@systeme.lip6.fr, linux-security-module@vger.kernel.org, linux-integrity@vger.kernel.org Subject: Re: [PATCH 1/2] mm, treewide: Rename kzfree() to kfree_sensitive() In-Reply-To: <20200413211550.8307-2-longman@redhat.com> Message-ID: References: <20200413211550.8307-1-longman@redhat.com> <20200413211550.8307-2-longman@redhat.com> User-Agent: Alpine 2.21 (DEB 202 2017-01-01) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org On Mon, 13 Apr 2020, Waiman Long wrote: > As said by Linus: > > A symmetric naming is only helpful if it implies symmetries in use. > Otherwise it's actively misleading. > > In "kzalloc()", the z is meaningful and an important part of what the > caller wants. > > In "kzfree()", the z is actively detrimental, because maybe in the > future we really _might_ want to use that "memfill(0xdeadbeef)" or > something. The "zero" part of the interface isn't even _relevant_. > > The main reason that kzfree() exists is to clear sensitive information > that should not be leaked to other future users of the same memory > objects. > > Rename kzfree() to kfree_sensitive() to follow the example of the > recently added kvfree_sensitive() and make the intention of the API > more explicit. In addition, memzero_explicit() is used to clear the > memory to make sure that it won't get optimized away by the compiler. > > The renaming is done by using the command sequence: > > git grep -w --name-only kzfree |\ > xargs sed -i 's/\bkzfree\b/kfree_sensitive/' > > followed by some editing of the kfree_sensitive() kerneldoc and the > use of memzero_explicit() instead of memset(). > > Suggested-by: Joe Perches > Signed-off-by: Waiman Long Acked-by: David Rientjes