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]) by smtp.lore.kernel.org (Postfix) with ESMTP id E97F7C43334 for ; Thu, 2 Jun 2022 18:41:37 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 667796B0071; Thu, 2 Jun 2022 14:41:37 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 5EF546B0073; Thu, 2 Jun 2022 14:41:37 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 48D706B0074; Thu, 2 Jun 2022 14:41:37 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id 35EE16B0071 for ; Thu, 2 Jun 2022 14:41:37 -0400 (EDT) Received: from smtpin19.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay13.hostedemail.com (Postfix) with ESMTP id D5AE160D99 for ; Thu, 2 Jun 2022 18:41:36 +0000 (UTC) X-FDA: 79534164192.19.9089710 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by imf05.hostedemail.com (Postfix) with ESMTP id D4A74100026 for ; Thu, 2 Jun 2022 18:41:00 +0000 (UTC) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 4C4D9B82042; Thu, 2 Jun 2022 18:41:34 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C1B92C385A5; Thu, 2 Jun 2022 18:41:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1654195293; bh=BiBtVCnOnVCnBb/s+KIDqG6XVHJWq/doHqTwPsrqDDg=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=wcfwJ2N6m6iYkyLPXAvxRttyDCvkGAqeByInXKFMdk9RkuPrnImtmzX0YBMzcdDw5 1luGPe9SVVlz0r6sPFfRuMQgvEfILrNJZPihvvI2uKazI53rfhy38KX9b7BkUgtnMD CuPQREkUiB1ovWxFj1XxqayxFBkbwg4GW5TJpvyc= Date: Thu, 2 Jun 2022 11:41:32 -0700 From: Andrew Morton To: Roman Gushchin Cc: linux-mm@kvack.org, Dave Chinner , linux-kernel@vger.kernel.org, Kent Overstreet , Hillf Danton , Christophe JAILLET , Muchun Song Subject: Re: [PATCH v5 6/6] mm: shrinkers: add scan interface for shrinker debugfs Message-Id: <20220602114132.f6e5675b2d2a4085b9b1e8c4@linux-foundation.org> In-Reply-To: References: <20220601032227.4076670-1-roman.gushchin@linux.dev> <20220601032227.4076670-7-roman.gushchin@linux.dev> <20220601142351.5e04fea5586ca51898d8785f@linux-foundation.org> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.33; x86_64-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Stat-Signature: cj8n9gxtr1ooppqb78sru59uze4gostm X-Rspam-User: Authentication-Results: imf05.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=wcfwJ2N6; dmarc=none; spf=pass (imf05.hostedemail.com: domain of akpm@linux-foundation.org designates 145.40.68.75 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: D4A74100026 X-HE-Tag: 1654195260-487846 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 Wed, 1 Jun 2022 17:56:22 -0700 Roman Gushchin wrote: > > > > > + ssize_t ret; > > > + > > > + if (copy_from_user(kbuf, buf, read_len)) > > > + return -EFAULT; > > > + kbuf[read_len] = '\0'; > > > + > > > + if (sscanf(kbuf, "%lu %d %lu", &ino, &nid, &nr_to_scan) < 2) > > > > Was it intentional to permit more than three args? > > Good catch! No, of course it wasn't intentional. > > Below is an updated version of this patch. > > ... > > + if (sscanf(kbuf, "%lu %d %lu", &ino, &nid, &nr_to_scan) != 2) > + return -EINVAL; s/2/3/methinks?