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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 626D0C25B08 for ; Wed, 17 Aug 2022 09:29:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231225AbiHQJ33 (ORCPT ); Wed, 17 Aug 2022 05:29:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56814 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229620AbiHQJ32 (ORCPT ); Wed, 17 Aug 2022 05:29:28 -0400 Received: from mail-pg1-x52c.google.com (mail-pg1-x52c.google.com [IPv6:2607:f8b0:4864:20::52c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9FF682E9C4 for ; Wed, 17 Aug 2022 02:29:27 -0700 (PDT) Received: by mail-pg1-x52c.google.com with SMTP id l64so11530295pge.0 for ; Wed, 17 Aug 2022 02:29:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=message-id:date:content-id:mime-version:subject:cc:to:from:from:to :cc; bh=kLiP6zcg3Ginhw+XDh+5eBGHIFnSXP2cU/cS9A26ohQ=; b=mhaFtdvQYUfjx8JrB3TC/rmyx2q4Aqo5rz9NGQsc+XHmtVXzYnAv3ukftr+3BbbJvN fYy+n0Dnz8hbd1N2ffY6EmajtRP3d8vYNSDfJAmP1yOHvevIDaaTGorbt6wQdqJKHYnx UrjV+MG7uK/u/aHjNitybhpLPsItf3CRWRcoFHdHzyJHGnuUM3Hxc6+PLJAMl+iy2gkh n4iG3LUtWgt9o1dL3UPmwVvJd1YlB5cJl5ihqQrWkX7ZtRlFOfHR/GEZ17QjMHZ6n32t dTlMwnB2cmzJOwiyeU77xe21i3/Qi4KcGwv64FqNcwXprED5dC7GIhDwh2VZvmYnaH0W RbjQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=message-id:date:content-id:mime-version:subject:cc:to:from :x-gm-message-state:from:to:cc; bh=kLiP6zcg3Ginhw+XDh+5eBGHIFnSXP2cU/cS9A26ohQ=; b=ZrpI5jGErgyjqNGQyz8eWcF1ApR/8Ut4d7w5bMGKItvmrsv42ONhUi5HnqEP5ON4Oi 9VwkwEHDIIxvpxHS1e4zn7ZxmIRduOy0OR1uAwzzPm/hecxm6VqQz46zBqo468ogPjKk o64MO6V6CNMzh0A0RGgxYPVcA0aI2j4MCRa01KXWnRf5PksXp88Q+HQhdc1sg1w1xeq0 1qAyFT7poVemOEs/qEWp1p5K2sCcXYAXkRIfTJ9Bac6BsqiJv3UkQbooiislRJc3CbL7 uABOUsA/C+MDxI6DBEHjD3rNxEQCsObO8YJun0xpA/QVs0rYAYhscn/HxT86chAChLEo dtoA== X-Gm-Message-State: ACgBeo3kLup/sNFWIwLqrad7GS22jERo+OLDGkl5QvkPee5W3llZLibm oZIGG88g/X3fjJfazp+/wtkvyU89ytw= X-Google-Smtp-Source: AA6agR7z3q5sONuMTch3iLMuS6kBlsk2j74Nd4RRjDhS14hlvXcke8WyJPNbrCZF+wTO5cKanJSbvQ== X-Received: by 2002:a05:6a00:1a88:b0:52f:52df:ce1d with SMTP id e8-20020a056a001a8800b0052f52dfce1dmr25087851pfv.13.1660728567110; Wed, 17 Aug 2022 02:29:27 -0700 (PDT) Received: from jromail.nowhere (h219-110-108-104.catv02.itscom.jp. [219.110.108.104]) by smtp.gmail.com with ESMTPSA id u18-20020a170902e21200b00172a670607asm44903plb.300.2022.08.17.02.29.26 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 17 Aug 2022 02:29:26 -0700 (PDT) Received: from localhost ([127.0.0.1] helo=jrobl) by jrobl id 1oOFMa-0001z9-JP ; Wed, 17 Aug 2022 18:29:24 +0900 From: "J. R. Okajima" To: neilb@suse.de, trond.myklebust@hammerspace.com Cc: linux-nfs@vger.kernel.org Subject: NFS, two d_delete() calls in nfs_unlink() MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-ID: <7633.1660728564.1@jrobl> Date: Wed, 17 Aug 2022 18:29:24 +0900 Message-ID: <7634.1660728564@jrobl> Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org Hello NeilBrown and Trond Myklebust, By the commin in v6.0-rc1, 3c59366c207e 2022-08-08 NFS: don't unhash dentry during unlink/rename nfs_unlink() stopped calling __d_drop(). And it MAY cause two d_delete() calls. If it happens, the second call leads to NULL pointer access because d_inode is already cleared. Here is the detail. nfs_unlink() + nfs_safe_remove() + NFS_PROTO(dir)->remove() <-- returns ENOENT + nfs_dentry_handle_enoent() + if (simple_positive()) d_delete() <-- 1st call and d_inode is cleared + nfs_dentry_remove_handle_error() + if (ENOENT) d_delete() <-- second call and NULL d_inode is accessed How about adding a condition for d_delete() call in nfs_dentry_remove_handle_error(), such like simple_positive()? J. R. Okajima