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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id D2D94D74960 for ; Fri, 19 Dec 2025 07:04:47 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 028466B0088; Fri, 19 Dec 2025 02:04:47 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id EEE2A6B0089; Fri, 19 Dec 2025 02:04:46 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id DEC146B008A; Fri, 19 Dec 2025 02:04:46 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id C90F26B0088 for ; Fri, 19 Dec 2025 02:04:46 -0500 (EST) Received: from smtpin23.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id 4C10E13B0A2 for ; Fri, 19 Dec 2025 07:04:46 +0000 (UTC) X-FDA: 84235332972.23.4631122 Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by imf08.hostedemail.com (Postfix) with ESMTP id 90A1516000E for ; Fri, 19 Dec 2025 07:04:44 +0000 (UTC) Authentication-Results: imf08.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=TOr918U1; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf08.hostedemail.com: domain of rppt@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=rppt@kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1766127884; a=rsa-sha256; cv=none; b=XQTHA7R8sA1/GzADU4eU/N1b38lm/0/4j3i82vUrmZp7N/Cbtwlyzx9gFTHsUeS5eErgkX iCwl2DXfzJKx709lJkEcNclJ/xLHwQQpRn0Lp1UqAaRs5+CUzzXFJV8RoBiwMXmnAsgd2X 6aFET7zzll+DMUUpJdImjaTt2jFKX84= ARC-Authentication-Results: i=1; imf08.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=TOr918U1; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf08.hostedemail.com: domain of rppt@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=rppt@kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1766127884; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=y8pIRHj989/yP044y8FmVi5laJrkIYribs4FwH/K2J0=; b=csB0H0lKa1Tx2DCMk+X9h1F6NK2AjuURFd5zX2WCMWBqPzyS4g3ihladYPh6cIVmC1xrgv oDvaSpaTZkcwGsukQMabNz7maDnQZS74SnHS49pMfTph+8bgwJDbCXmpzZZZY97w7mN20V 40tQzNQt0rmJMsTgLQdsHlJahqxlN/I= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sea.source.kernel.org (Postfix) with ESMTP id 9B61243589; Fri, 19 Dec 2025 07:04:43 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A7AD3C4CEF1; Fri, 19 Dec 2025 07:04:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1766127883; bh=7pM3pg1E+9Zhsdy3FeEbki6cuZHG9Wz4UgMWqEJpnNo=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=TOr918U1kBoZTAW5Zj1HzhhsHwDFWVt795xvXCPwfM6E+PyiG9LY60zL1vfEb0RGX BOaVX40lZQaLWgAaghTz47Y8D2PAj338vLnd3yeAWHOH1xeiMIUP+VwqxG8iazyZRz DllbqGBkxwWKORxC/b4IqP0Y1gLEm0VHXomya3cgfHlvpuNMFSMTpj319w01wgL7d9 TZ+J64XgCH7cmGJphFXXy8eAQN/cSbo6xtLpsWrXG+LJM6bJT27gvIBlX8jvjwsfcv jJDcoFzBbJyhf2ayhVy9BIG7iR4VmxYCQXn1zbDN7yxY3Qelg8xMTnKCpHtQsgPeh/ sHhI61OJzC5sg== Date: Fri, 19 Dec 2025 09:04:34 +0200 From: Mike Rapoport To: Thorsten Blum Cc: Ingo Molnar , Peter Zijlstra , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Valentin Schneider , Andrew Morton , David Hildenbrand , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Suren Baghdasaryan , Michal Hocko , Kees Cook , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] fork: Replace simple_strtoul with kstrtoul in coredump_filter_setup Message-ID: References: <20251215142152.4082-2-thorsten.blum@linux.dev> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20251215142152.4082-2-thorsten.blum@linux.dev> X-Rspam-User: X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: 90A1516000E X-Stat-Signature: gcoubgkisncg1yrn7ffdx84yhhguy8qo X-HE-Tag: 1766127884-565752 X-HE-Meta: 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 nQDm66dw KmGtBf/z65nzi8nnMMZgtpADy4vBHuwMKdzH/HHc18oDLWJDCip1smCbyPT6ZnM7nrasyrUlOtt4k/OrCgAL1jUeacLbA/6a0EI85z20J1cD9gys/HAKR5zw/sp6LrlOBMYD7kaX1egm0P754IvZLf3oUA9FAHc026Sx/38m2OCCkTpy9dqOwQrKH5tKEvspAf/YnzvSX+BHTk+8OeSe9BVhNSk0Z9sF3Ui6YPHDleQBlj3Mz5Bjd4hnqByaTTwnibJVv1UAZNu5VqSfvySHV+PzanJn7WuKOsSmlSt9aNuqCnRVQ39jVxpNL/M74eMUlhTGpU6QJtolV0aw9gVvkThDWUNAFlbtOd3dGe8osQAzaLec= 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: List-Subscribe: List-Unsubscribe: On Mon, Dec 15, 2025 at 03:21:52PM +0100, Thorsten Blum wrote: > Replace simple_strtoul() with the recommended kstrtoul() for parsing the > 'coredump_filter=' boot parameter. > > Check the return value of kstrtoul() and reject invalid values. This > adds error handling while preserving behavior for existing values, and > removes use of the deprecated simple_strtoul() helper. The current code > silently sets 'default_dump_filter = 0' if parsing fails, instead of > leaving the default value (MMF_DUMP_FILTER_DEFAULT) unchanged. > > Rename the static variable 'default_dump_filter' to 'coredump_filter' > since it does not necessarily contain the default value and the current > name can be misleading. > > Signed-off-by: Thorsten Blum Acked-by: Mike Rapoport (Microsoft) > --- > kernel/fork.c | 11 ++++++----- > 1 file changed, 6 insertions(+), 5 deletions(-) > > diff --git a/kernel/fork.c b/kernel/fork.c > index b1f3915d5f8e..f33ee7fe53ad 100644 > --- a/kernel/fork.c > +++ b/kernel/fork.c > @@ -1012,13 +1012,14 @@ static struct task_struct *dup_task_struct(struct task_struct *orig, int node) > > __cacheline_aligned_in_smp DEFINE_SPINLOCK(mmlist_lock); > > -static unsigned long default_dump_filter = MMF_DUMP_FILTER_DEFAULT; > +static unsigned long coredump_filter = MMF_DUMP_FILTER_DEFAULT; > > static int __init coredump_filter_setup(char *s) > { > - default_dump_filter = > - (simple_strtoul(s, NULL, 0) << MMF_DUMP_FILTER_SHIFT) & > - MMF_DUMP_FILTER_MASK; > + if (kstrtoul(s, 0, &coredump_filter)) > + return 0; > + coredump_filter <<= MMF_DUMP_FILTER_SHIFT; > + coredump_filter &= MMF_DUMP_FILTER_MASK; > return 1; > } > > @@ -1104,7 +1105,7 @@ static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p, > __mm_flags_overwrite_word(mm, mmf_init_legacy_flags(flags)); > mm->def_flags = current->mm->def_flags & VM_INIT_DEF_MASK; > } else { > - __mm_flags_overwrite_word(mm, default_dump_filter); > + __mm_flags_overwrite_word(mm, coredump_filter); > mm->def_flags = 0; > } > > -- > Thorsten Blum > GPG: 1D60 735E 8AEF 3BE4 73B6 9D84 7336 78FD 8DFE EAD4 > -- Sincerely yours, Mike.