From patchwork Mon Aug 24 08:31:27 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 265102 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=-13.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=ham 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 3F64AC433E1 for ; Mon, 24 Aug 2020 09:11:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 13ED2206BE for ; Mon, 24 Aug 2020 09:11:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1598260307; bh=ObB8scPObpqBxHgYAz3uByh5AW7ZXQnLWcvr0snphRw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=cEVaoqyW243gAgTIYV0cuyE+e5O0guaXh5Y48wLkXAbeuU51dygzj0kEwed2rJjj1 056ql1nXF3WYzoKU9/hNmrynDiiXpruhU+fyl8NqEvhJDGJHUpc7qhuoTOo53PeqCr iNdvw+VwdXEPFKAQp4Mu/n4Ryob8thcjtd8J2GjI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727986AbgHXJLp (ORCPT ); Mon, 24 Aug 2020 05:11:45 -0400 Received: from mail.kernel.org ([198.145.29.99]:40652 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730511AbgHXI4R (ORCPT ); Mon, 24 Aug 2020 04:56:17 -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 39EEC22D07; Mon, 24 Aug 2020 08:56:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1598259376; bh=ObB8scPObpqBxHgYAz3uByh5AW7ZXQnLWcvr0snphRw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Cs12CjfLnqJ8hVtGNC3xfWxFHtJIkJmwM+kcRsagr8V04Xv/oaI707lmLPmt6F1Xj FrMKH36qw3BjsOgrBUg/GJbI4i6pzfv0Bpsnn/OHvwuArb3IoXK69uU/vqDmzqow6T LCP69gIgxkwRSwy2fEm04u/DLeFvg3/IFen7vWNg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eiichi Tsukata , "Darrick J. Wong" , Sasha Levin Subject: [PATCH 4.19 36/71] xfs: Fix UBSAN null-ptr-deref in xfs_sysfs_init Date: Mon, 24 Aug 2020 10:31:27 +0200 Message-Id: <20200824082357.690791630@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200824082355.848475917@linuxfoundation.org> References: <20200824082355.848475917@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Eiichi Tsukata [ Upstream commit 96cf2a2c75567ff56195fe3126d497a2e7e4379f ] If xfs_sysfs_init is called with parent_kobj == NULL, UBSAN shows the following warning: UBSAN: null-ptr-deref in ./fs/xfs/xfs_sysfs.h:37:23 member access within null pointer of type 'struct xfs_kobj' Call Trace: dump_stack+0x10e/0x195 ubsan_type_mismatch_common+0x241/0x280 __ubsan_handle_type_mismatch_v1+0x32/0x40 init_xfs_fs+0x12b/0x28f do_one_initcall+0xdd/0x1d0 do_initcall_level+0x151/0x1b6 do_initcalls+0x50/0x8f do_basic_setup+0x29/0x2b kernel_init_freeable+0x19f/0x20b kernel_init+0x11/0x1e0 ret_from_fork+0x22/0x30 Fix it by checking parent_kobj before the code accesses its member. Signed-off-by: Eiichi Tsukata Reviewed-by: Darrick J. Wong [darrick: minor whitespace edits] Signed-off-by: Darrick J. Wong Signed-off-by: Sasha Levin --- fs/xfs/xfs_sysfs.h | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/fs/xfs/xfs_sysfs.h b/fs/xfs/xfs_sysfs.h index e9f810fc67317..43585850f1546 100644 --- a/fs/xfs/xfs_sysfs.h +++ b/fs/xfs/xfs_sysfs.h @@ -32,9 +32,11 @@ xfs_sysfs_init( struct xfs_kobj *parent_kobj, const char *name) { + struct kobject *parent; + + parent = parent_kobj ? &parent_kobj->kobject : NULL; init_completion(&kobj->complete); - return kobject_init_and_add(&kobj->kobject, ktype, - &parent_kobj->kobject, "%s", name); + return kobject_init_and_add(&kobj->kobject, ktype, parent, "%s", name); } static inline void