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=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,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 C5147C54FCB for ; Mon, 27 Apr 2020 17:31:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8F5C02076A for ; Mon, 27 Apr 2020 17:31:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588008698; bh=sQuHvJ8hED/DxfS8jREtJCqTkhgs+wdBCB4nmSyo64Q=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=IcA54Enxi/Os/Su/zeEae9rGFac+Zof/Lpnz5GGxBKNPLRUnROjwEAJP9JDayH/mH IDHnhtBbW1aFLMaRgvdQW9Gu17elzG/BCJ997UeKkV8bHMWzCnhVdY+wUUT5zU2SOG B+NEqLCHqZ92IcbgYD/qfXuESpsiWS/tMbWnvNyE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726448AbgD0Rbh (ORCPT ); Mon, 27 Apr 2020 13:31:37 -0400 Received: from mail.kernel.org ([198.145.29.99]:45672 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726244AbgD0Rbh (ORCPT ); Mon, 27 Apr 2020 13:31:37 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 4464E20775; Mon, 27 Apr 2020 17:31:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588008696; bh=sQuHvJ8hED/DxfS8jREtJCqTkhgs+wdBCB4nmSyo64Q=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=MSUAHvjim2B5zkwUH81DpVvb9f5Af9nvOVGON+fWy6Pl3f4f9JKnPNWBguiH6soWT M51gp+VtCd++fOceKouXW6MDiUTJpEqgW/2ghM+k06Rh0qcXC8NOwbnXDuHv/+HKb0 FbXnluTxO5RPPGoGWxT4wjGOADtC/NiVSgAJxzMI= Date: Mon, 27 Apr 2020 19:31:34 +0200 From: Greg Kroah-Hartman To: youngjun Cc: Tejun Heo , linux-kernel@vger.kernel.org Subject: Re: [PATCH] kernfs: fix possibility of NULL pointer dereference. Message-ID: <20200427173134.GC3936841@kroah.com> References: <20200427164836.48765-1-her0gyugyu@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200427164836.48765-1-her0gyugyu@gmail.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Apr 27, 2020 at 09:48:36AM -0700, youngjun wrote: > When dentry is negative, "kernfs_dentry_node" returns NULL. > In this case, "kernfs_root" dereferences NULL pointer. > > Signed-off-by: youngjun > --- > fs/kernfs/dir.c | 18 ++++++++++-------- > 1 file changed, 10 insertions(+), 8 deletions(-) And how can this be triggered on a kernfs filesystem? thanks, greg k-h