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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A343CC433EF for ; Sun, 24 Oct 2021 05:38:12 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 5670660F93 for ; Sun, 24 Oct 2021 05:38:12 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 5670660F93 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id B5A006B006C; Sun, 24 Oct 2021 01:38:11 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id B09816B0071; Sun, 24 Oct 2021 01:38:11 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 9F735940007; Sun, 24 Oct 2021 01:38:11 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0044.hostedemail.com [216.40.44.44]) by kanga.kvack.org (Postfix) with ESMTP id 8C2D46B006C for ; Sun, 24 Oct 2021 01:38:11 -0400 (EDT) Received: from smtpin40.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 412DB32064 for ; Sun, 24 Oct 2021 05:38:11 +0000 (UTC) X-FDA: 78730225182.40.B416C9E Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf06.hostedemail.com (Postfix) with ESMTP id C9B11801AB02 for ; Sun, 24 Oct 2021 05:38:10 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id CE9E360C4A; Sun, 24 Oct 2021 05:38:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1635053888; bh=rjQWlX3TCvMDgEHLTPEDl04VRpnK/72Rf+QAmajZC6Q=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=OWdrVFBebnH1ElaX1rUDLya9cgAkyp9NAbj2xxAxQsKvHCjhy7JjfQdfhTus79Gdw 80fF/zu6ODHzdOozSbaaCzh2pmk7XpEkuoCAD8igIfPS5e7FfqQedKqdx7x/a4CvT7 DhrGFcGwCX4zHrNKGy4119S2L1tPw/PAKZb256YRY3N8aUsEpurYXhW1QxnrXCRqHu MEq0SQ82aJPtKjXXcf1X7U3RMk0opYbQB+NvTzJksACiR2zWRz8mUO1KoMX2XqzEjR Vkej9yY1V8M2y0TmmmB/+MYytzGcU/Q92ERPakZi2d9DD4UQ6gdiXJxseLrcJi45A+ vkksxN4hYUzxQ== Date: Sun, 24 Oct 2021 08:37:59 +0300 From: Mike Rapoport To: Matthew Wilcox Cc: Kees Cook , Dmitry Vyukov , syzbot , Jordy Zomer , akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, syzkaller-bugs@googlegroups.com Subject: Re: [syzbot] WARNING: refcount bug in sys_memfd_secret Message-ID: References: <00000000000062d0fc05cef24c57@google.com> <088FF23B-CD8E-4E53-B702-53E2C2382062@chromium.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: C9B11801AB02 X-Stat-Signature: pdboxkh9itpcoukrc96ppgxz1eaq8ryu Authentication-Results: imf06.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=OWdrVFBe; spf=pass (imf06.hostedemail.com: domain of rppt@kernel.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=rppt@kernel.org; dmarc=pass (policy=none) header.from=kernel.org X-HE-Tag: 1635053890-35645 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 Sat, Oct 23, 2021 at 11:46:18PM +0100, Matthew Wilcox wrote: > On Sat, Oct 23, 2021 at 10:03:11AM -0700, Kees Cook wrote: > > On October 23, 2021 8:27:28 AM PDT, Mike Rapoport wrote: > > >and my first reaction was to send a revert the untested commit 110860541f44 > > >("mm/secretmem: use refcount_t instead of atomic_t"). > > I think you should. This isn't a real problem. Do you mean that creation of 4 billion of file descriptors is not feasible? -- Sincerely yours, Mike.