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=-0.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 0F0E6C47258 for ; Tue, 5 May 2020 20:35:25 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id C68F620757 for ; Tue, 5 May 2020 20:35:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="REiW3W0M" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C68F620757 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 5DFFC8E0006; Tue, 5 May 2020 16:35:24 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 590868E0003; Tue, 5 May 2020 16:35:24 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 4A6AC8E0006; Tue, 5 May 2020 16:35:24 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0066.hostedemail.com [216.40.44.66]) by kanga.kvack.org (Postfix) with ESMTP id 30EBC8E0003 for ; Tue, 5 May 2020 16:35:24 -0400 (EDT) Received: from smtpin09.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id DA051824559C for ; Tue, 5 May 2020 20:35:23 +0000 (UTC) X-FDA: 76783820526.09.sofa71_8661385e89042 X-HE-Tag: sofa71_8661385e89042 X-Filterd-Recvd-Size: 2493 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf41.hostedemail.com (Postfix) with ESMTP for ; Tue, 5 May 2020 20:35:23 +0000 (UTC) Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 2728020752; Tue, 5 May 2020 20:35:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588710922; bh=FlarCttK714TCgXtLmYHtw4n67Swh0WSbhkChXfoK6Y=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=REiW3W0Ma8o3zstTFwYlU20TscGpSEG9Ai+jA01wL570DTG19447riGJRlCdoUgwy whVbWcZYGa0UsxP2sQkC69QmhA/BNYTM7mgR46rxKa87WTynbSZB0ALYZKJqDAiytr sBAqhbsUS4k/vPLw2zQ1884irPHC7ElqjGpJt6fo= Date: Tue, 5 May 2020 13:35:21 -0700 From: Andrew Morton To: David Howells Cc: Waiman Long , Jarkko Sakkinen , James Morris , "Serge E. Hallyn" , linux-mm@kvack.org, keyrings@vger.kernel.org, linux-kernel@vger.kernel.org, Linus Torvalds , Joe Perches , Matthew Wilcox , David Rientjes Subject: Re: [PATCH v3] mm: Add kvfree_sensitive() for freeing sensitive data objects Message-Id: <20200505133521.eb8901d0b92e09452191ab49@linux-foundation.org> In-Reply-To: <694340.1586290917@warthog.procyon.org.uk> References: <694135.1586290793@warthog.procyon.org.uk> <20200407200318.11711-1-longman@redhat.com> <694340.1586290917@warthog.procyon.org.uk> X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.31; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, 07 Apr 2020 21:21:57 +0100 David Howells wrote: > David Howells wrote: > > > > if (unlikely(key_data)) > > > - __kvzfree(key_data, key_data_len); > > > + kvfree_sensitive(key_data, key_data_len); > > > > I think the if-statement is redundant. > > Ah - I see that you explicitly wanted to keep it. Why's that? > There's a good chance it'll get janitored at some point. Indeed. Perhaps add a few little comments to explain the reasoning and to keep the janitorial fingers away?