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 9051FE7D0A1 for ; Thu, 21 Sep 2023 23:27:55 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 21D376B027A; Thu, 21 Sep 2023 19:27:55 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 1CD886B027B; Thu, 21 Sep 2023 19:27:55 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 095D16B027C; Thu, 21 Sep 2023 19:27:55 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id EA2F76B027A for ; Thu, 21 Sep 2023 19:27:54 -0400 (EDT) Received: from smtpin25.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id BA4E280891 for ; Thu, 21 Sep 2023 23:27:54 +0000 (UTC) X-FDA: 81262194468.25.CDBCAE5 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by imf30.hostedemail.com (Postfix) with ESMTP id ECE7080012 for ; Thu, 21 Sep 2023 23:27:52 +0000 (UTC) Authentication-Results: imf30.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b="oNLDJ5/1"; dmarc=none; spf=pass (imf30.hostedemail.com: domain of akpm@linux-foundation.org designates 145.40.68.75 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1695338873; 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:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=kihQxl1G0jpVDyuXxocl6/1jo7sGaJhEu0m1tC9mTUc=; b=ZigHuq127eGv88LOOvZLVahGZByT3MxNoCbg/QArq+6yckNDQKlcmSdi8UK5lB3a0qMPus fW/U7K6pBrsn7lNNT9zjMzZpNOKD7JiHDwbrWoP00LWwwpvwJkANAfdd+m7DQd7ZRHV2x0 rt32eaZY5OQ7I3XDllwtj9hkQuK/PeA= ARC-Authentication-Results: i=1; imf30.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b="oNLDJ5/1"; dmarc=none; spf=pass (imf30.hostedemail.com: domain of akpm@linux-foundation.org designates 145.40.68.75 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1695338873; a=rsa-sha256; cv=none; b=BVTqsd+7dqP7MQy25hr67u1LGWmixMqL79pIvkra0dBd0ACQ0snqfgPDMmljUEyAmItMJq VantGx+BtkfhBvl2jJDc4rErnmlBLmYNTud591Wtu03/9W41856nvvGaVc0RKca3OIumO7 RATeXjW2xjpZjkGiFZbFglTzZL+NC8o= Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 24A12B8224A; Thu, 21 Sep 2023 23:27:51 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 786FDC433C8; Thu, 21 Sep 2023 23:27:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1695338869; bh=SJbxiQb0unKA+nMj2mRavTDir6g83Ub6YVE1qG4Rjns=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=oNLDJ5/1ert+fipFAqVCBE140YejWbtzCnP3HKI6PchHFLLHn3KPqD86onbbwNuQ2 zvLy5pP+yrLkXEXKb1D0eq9MXQ8BmPW7/D6azUQsFeNbwK+NP7ySXNUHezM7O5PKzK PHI1/5FErfcroy0Vvda8f9adqRLTIj+H3GLapQu4= Date: Thu, 21 Sep 2023 16:27:48 -0700 From: Andrew Morton To: Matthew Wilcox Cc: "Liam R. Howlett" , maple-tree@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, pedro.falcato@gmail.com, stable Subject: Re: [PATCH 0/2] maple_tree: Fix mas_prev() state regression. Message-Id: <20230921162748.a85eb5af766e0662e4f22a5e@linux-foundation.org> In-Reply-To: References: <20230921181236.509072-1-Liam.Howlett@oracle.com> <20230921112521.fc07c658804f4e188179da77@linux-foundation.org> <20230921185330.j5jw3oms4tc6crkf@revolver> X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: ECE7080012 X-Rspam-User: X-Rspamd-Server: rspam05 X-Stat-Signature: cpqy6geohommnu8pn7zbxz3ryyrdg3fc X-HE-Tag: 1695338872-341630 X-HE-Meta: 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 Mfy8vFeK 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 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 Thu, 21 Sep 2023 20:23:11 +0100 Matthew Wilcox wrote: > > > It isn't clear what are the user-visible effects of this flaw? Please > > > send this along and I'll paste it in. > > > > > > User may notice that mas_prev() or mas_next() calls that result in going > > outside of the limit passed to the call will cause incorrect returns on > > subsequent calls using that maple state, such as mas_find() skipping an > > entry. > > When Andrew says "User visible" he means "userspace visible". Not > "in kernel user visible". What are the _consequences_. Thanks ;) We have a Link: (https://gist.github.com/heatd/85d2971fae1501b55b6ea401fbbe485b) but it takes us to the reproducer code. If it took us to Pedro's initial bug report then the sun would shine and birds would sing.