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 AE5FAEEB57A for ; Sat, 9 Sep 2023 00:44:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346193AbjIIAoT (ORCPT ); Fri, 8 Sep 2023 20:44:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33118 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1346200AbjIIAni (ORCPT ); Fri, 8 Sep 2023 20:43:38 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C29704226; Fri, 8 Sep 2023 17:41:01 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E7CEBC116AB; Sat, 9 Sep 2023 00:40:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1694220044; bh=kOtzIdYvM65eOSCLmigwS5A6OwdOKeLzb2TKCJOMY8I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=m2kOOVNsTAu95GQXG7NqdBGF5E9p1P3pDBClN93RkYlxOVB9iFBrKzUuR24TD9NNl hy+tKHf5+1TpMyjToOvL8bTN5eFx1IORw4o7wEjyMbL7JzyMheXaQoRURCjDKYK8eb dSUucrQIXak4sBuIhLqBxX9NVeMVvxDpKQMm05Nyh2sHuYr9jQ/6xnbum/tViWaq1+ B+HDX19BhqSUtl0NOHEVIJ70JD9ZExuM+YIA4cBp6U8hunZ3o1ow0AkzfY8t4/6lom 9NZnCNR/N+ST79Z3S2jjYwi7CtWGQizttSe9FJ+2G082aYmLmwFeddqR7cIJ8BVsUk /x8Hax+C4lG6A== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Zhen Lei , Greg Kroah-Hartman , Sasha Levin Subject: [PATCH AUTOSEL 5.4 14/14] kobject: Add sanity check for kset->kobj.ktype in kset_register() Date: Fri, 8 Sep 2023 20:40:14 -0400 Message-Id: <20230909004015.3580832-14-sashal@kernel.org> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230909004015.3580832-1-sashal@kernel.org> References: <20230909004015.3580832-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 5.4.256 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Zhen Lei [ Upstream commit 4d0fe8c52bb3029d83e323c961221156ab98680b ] When I register a kset in the following way: static struct kset my_kset; kobject_set_name(&my_kset.kobj, "my_kset"); ret = kset_register(&my_kset); A null pointer dereference exception is occurred: [ 4453.568337] Unable to handle kernel NULL pointer dereference at \ virtual address 0000000000000028 ... ... [ 4453.810361] Call trace: [ 4453.813062] kobject_get_ownership+0xc/0x34 [ 4453.817493] kobject_add_internal+0x98/0x274 [ 4453.822005] kset_register+0x5c/0xb4 [ 4453.825820] my_kobj_init+0x44/0x1000 [my_kset] ... ... Because I didn't initialize my_kset.kobj.ktype. According to the description in Documentation/core-api/kobject.rst: - A ktype is the type of object that embeds a kobject. Every structure that embeds a kobject needs a corresponding ktype. So add sanity check to make sure kset->kobj.ktype is not NULL. Signed-off-by: Zhen Lei Link: https://lore.kernel.org/r/20230805084114.1298-2-thunder.leizhen@huaweicloud.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- lib/kobject.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/lib/kobject.c b/lib/kobject.c index 0c6d17503a113..c4025a880d753 100644 --- a/lib/kobject.c +++ b/lib/kobject.c @@ -877,6 +877,11 @@ int kset_register(struct kset *k) if (!k) return -EINVAL; + if (!k->kobj.ktype) { + pr_err("must have a ktype to be initialized properly!\n"); + return -EINVAL; + } + kset_init(k); err = kobject_add_internal(&k->kobj); if (err) -- 2.40.1