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=-3.8 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, MAILING_LIST_MULTI,SIGNED_OFF_BY,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 1E2CFC43331 for ; Tue, 24 Mar 2020 18:24:59 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id D422720714 for ; Tue, 24 Mar 2020 18:24:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="qWQ0JOE3" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D422720714 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 8BACB6B0007; Tue, 24 Mar 2020 14:24:58 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 86BBC6B0008; Tue, 24 Mar 2020 14:24:58 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 781BA6B000A; Tue, 24 Mar 2020 14:24:58 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0003.hostedemail.com [216.40.44.3]) by kanga.kvack.org (Postfix) with ESMTP id 60C506B0007 for ; Tue, 24 Mar 2020 14:24:58 -0400 (EDT) Received: from smtpin04.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id DC89918779B91 for ; Tue, 24 Mar 2020 18:24:57 +0000 (UTC) X-FDA: 76631082234.04.sheet52_2b4ad07f66143 X-HE-Tag: sheet52_2b4ad07f66143 X-Filterd-Recvd-Size: 4297 Received: from mail-qk1-f193.google.com (mail-qk1-f193.google.com [209.85.222.193]) by imf01.hostedemail.com (Postfix) with ESMTP for ; Tue, 24 Mar 2020 18:24:57 +0000 (UTC) Received: by mail-qk1-f193.google.com with SMTP id u4so8491839qkj.13 for ; Tue, 24 Mar 2020 11:24:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=RconwbLGvobrkQrLA8HZT5QCPO0hEEsGfTPRzr6x1ls=; b=qWQ0JOE3fCDg+RdT+hVndA3MY+mCBruUcX/KRXX1erbOlMR8BmWY+rmW0XC5KEltTK Esqctl8cGeg6M5mbdM8kJg6O7WkZBUw3rNFBdmELweVdBaRROiXkV4Idm8F4A2Xw8FGn codkCjZJZWnEcuySG4NFSH1GOpywlWqjp/ZObBdqDN8LWcvTkIpYJySbrrlqjHUJVnMK 6B1SmqHfjnjazYbnBSmOXN1FZ9FQHMPPeavkMV5IlGpVuubHIlf9/n0dhUS8aE/UTp9h ykQLr1yTU0sskkIulH6GAJcxxy6mDya6Pta2xnH7x6y56Jqqh4TVShb+eO9r1Ar3lO9I awnA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to; bh=RconwbLGvobrkQrLA8HZT5QCPO0hEEsGfTPRzr6x1ls=; b=NKHEAGMJnm4TGEA2CK6sLKFlQYAIhKiVXgaTWIKBxVV2qR6JKHHWI1YmJijfOgPCke C2pO25MVp1KqxY2IWrfNX06CbEPlFj/dRXIRmqKYCWOd2uHTH7BhHzPQrn7i7TjP5CTC ZJizpUiWNAJo/4J81L1CC5+BWAbvvPOvOCRTCWdAzNXmFRgJCjXxVxGyq/TxXyk5It2F Jkiyai2RJbQBbJ8J0FkpXdEQQZpZSmoQTdcOCFG6rUEKnEKUVwz2sWIn5X3yFQk7+H8R tIcjQNKQjrMaksSDy0yHj8BcHjLsZ0BxM+/jC0Rg28PDdSuekqfu0hi6SmYPL3RMWFcy mE+g== X-Gm-Message-State: ANhLgQ2Vlgag/egTE/unD2KHYh1jf+95V8U/RWj1LUYgW4RiYpdZVofj KNGILpfMDcqYG4NS2Q1y9Is= X-Google-Smtp-Source: ADFU+vtqLe2wnw4h8YDpEepGFhKK7We9Rhe1ZxfEVlqXh61lSnV6dWCn407Z4KLJK4FVGOuzufntxQ== X-Received: by 2002:a37:91c3:: with SMTP id t186mr26109176qkd.239.1585074296754; Tue, 24 Mar 2020 11:24:56 -0700 (PDT) Received: from localhost ([2620:10d:c091:480::19c2]) by smtp.gmail.com with ESMTPSA id h5sm13514266qkc.118.2020.03.24.11.24.55 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 24 Mar 2020 11:24:56 -0700 (PDT) Date: Tue, 24 Mar 2020 14:24:54 -0400 From: Tejun Heo To: Mina Almasry Cc: syzbot+cac0c4e204952cf449b1@syzkaller.appspotmail.com, Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Giuseppe Scrivano , mike.kravetz@oracle.com, rientjes@google.com Subject: Re: [PATCH -next] hugetlb_cgroup: fix illegal access to memory Message-ID: <20200324182454.GE162390@mtj.duckdns.org> References: <20200313223920.124230-1-almasrymina@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200313223920.124230-1-almasrymina@google.com> X-Bogosity: Ham, tests=bogofilter, spamicity=0.000001, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Fri, Mar 13, 2020 at 03:39:20PM -0700, Mina Almasry wrote: > This appears to be a mistake in commit faced7e0806cf ("mm: hugetlb > controller for cgroups v2"). Essentially that commit does > a hugetlb_cgroup_from_counter assuming that page_counter_try_charge has > initialized counter, but if page_counter_try_charge has failed then it > seems it does not initialize counter, so > hugetlb_cgroup_from_counter(counter) ends up pointing to random memory, > causing kasan to complain. > > Solution, simply use h_cg, instead of > hugetlb_cgroup_from_counter(counter), since that is a reference to the > hugetlb_cgroup anyway. After this change kasan ceases to complain. > > Signed-off-by: Mina Almasry > Reported-by: syzbot+cac0c4e204952cf449b1@syzkaller.appspotmail.com > Fixes: commit faced7e0806cf ("mm: hugetlb controller for cgroups v2") > Cc: Andrew Morton > Cc: linux-mm@kvack.org > Cc: linux-kernel@vger.kernel.org > Cc: Giuseppe Scrivano > Cc: Tejun Heo > Cc: mike.kravetz@oracle.com > Cc: rientjes@google.com Acked-by: Tejun Heo Thanks. -- tejun