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=-6.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, 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 9B380C55179 for ; Thu, 29 Oct 2020 15:31:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4053220796 for ; Thu, 29 Oct 2020 15:31:17 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="key not found in DNS" (0-bit key) header.d=szeredi.hu header.i=@szeredi.hu header.b="ZeVFlYxb" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728316AbgJ2PbQ (ORCPT ); Thu, 29 Oct 2020 11:31:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46542 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728307AbgJ2PbA (ORCPT ); Thu, 29 Oct 2020 11:31:00 -0400 Received: from mail-vs1-xe35.google.com (mail-vs1-xe35.google.com [IPv6:2607:f8b0:4864:20::e35]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5C6F4C0613D2 for ; Thu, 29 Oct 2020 08:21:07 -0700 (PDT) Received: by mail-vs1-xe35.google.com with SMTP id r1so1698608vsi.12 for ; Thu, 29 Oct 2020 08:21:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=szeredi.hu; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=G2vNhDEm3HbJWwlXQvfrqMnwz+Y6hXypKtoqXX91090=; b=ZeVFlYxbfCuY/CTkTlqJNy9tAAAQX1+083ZdKCIa7x1FWR21+Plm1CPrBsd03fL+a1 9kxhuhqHA5xuykUmXmhTjs+dynTESM5EFHJjUSvzEMHqzuKqmcs6r4xBJiNaMTBnPwr9 M9dts4aQTunZ21ku0hMwe6NKyEo9QpURz2Z28= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=G2vNhDEm3HbJWwlXQvfrqMnwz+Y6hXypKtoqXX91090=; b=bvU+EQPxYxfTmDrqRlUbaUyHOluVEzANGObwsK8JCneO6MG+wqFFop3Z2TNN62ebIJ kQuLSw6SpgtahBtDZ6Fq+FG75n4f3+6wxPr/WAgyguJQ1myvTUt/vllvr0su1F3UsZv7 kRl+uboMnAomFRVYK43AjUx/DZruz+R5lzVRqoTlciQmY8pAwfOQ5uhNDmsg7ILOCReD v9VedZuKF7Dsnjjm7ZIn2J8lLVLAnu+gZk6a/oTxcO1zSkzejsH+JF2NjOzUKJp6AslJ yN7tLiyfgO+XF5+/0uT5YbDA+Txo1+IJF05CAiyNBh7Yc1e2rHUDF3JX77ZOLesT6jfn M9kg== X-Gm-Message-State: AOAM5317yup4iBZ5ZQJD4KTjBOzETp0GuYbD4q9Dmh62mES7kn4Bw6UI xbIqqLciL05NPieaEWgeuTjqj1Fd6nEp1zrVU2YN8A== X-Google-Smtp-Source: ABdhPJyPUNHkn7dNetro3OoklJYl1bWTjUQtaDqS1cgdmcB2snVQpIK+qd+2mZzS1qZQtfW6kHTw+C8nB2PbP9ucmKI= X-Received: by 2002:a67:1442:: with SMTP id 63mr3605467vsu.0.1603984866514; Thu, 29 Oct 2020 08:21:06 -0700 (PDT) MIME-Version: 1.0 References: <89f0dbf6713ebd44ec519425e3a947e71f7aed55.camel@redhat.com> In-Reply-To: <89f0dbf6713ebd44ec519425e3a947e71f7aed55.camel@redhat.com> From: Miklos Szeredi Date: Thu, 29 Oct 2020 16:20:55 +0100 Message-ID: Subject: Re: WARN_ON(fuse_insert_writeback(root, wpa)) in tree_insert() To: Qian Cai Cc: Vivek Goyal , Stefan Hajnoczi , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, virtio-fs-list Content-Type: multipart/mixed; boundary="00000000000031f1b005b2d0d437" Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org --00000000000031f1b005b2d0d437 Content-Type: text/plain; charset="UTF-8" On Thu, Oct 29, 2020 at 4:02 PM Qian Cai wrote: > > On Wed, 2020-10-07 at 16:08 -0400, Qian Cai wrote: > > Running some fuzzing by a unprivileged user on virtiofs could trigger the > > warning below. The warning was introduced not long ago by the commit > > c146024ec44c ("fuse: fix warning in tree_insert() and clean up writepage > > insertion"). > > > > From the logs, the last piece of the fuzzing code is: > > > > fgetxattr(fd=426, name=0x7f39a69af000, value=0x7f39a8abf000, size=1) > > I can still reproduce it on today's linux-next. Any idea on how to debug it > further? Can you please try the attached patch? 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