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 3C164CE79CE for ; Wed, 20 Sep 2023 12:07:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235193AbjITMHr (ORCPT ); Wed, 20 Sep 2023 08:07:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40776 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235211AbjITMHq (ORCPT ); Wed, 20 Sep 2023 08:07:46 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2378B92 for ; Wed, 20 Sep 2023 05:07:41 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6827BC433CB; Wed, 20 Sep 2023 12:07:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1695211660; bh=Fvf9/DSqtBXdCBxQzC92ulSBuMJWTL/mA8CuIE6M4oA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ciVDSlOd8v6BO8Jf378WN5+iYQYO6d77gPnWueIgy2itJ8oFSHTBpuSi46oaLSPRB p3a6GwOy7eBQwNMi1aY+8+kjSPf11mdxYuSHqD5kq5iAI2RW5pEocDyYW65B23psfA BIHgX6thdQe7VKtLUGqP4/pDO6EwLZtKZGi0eaWE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Zhen Lei , Sasha Levin Subject: [PATCH 4.14 176/186] kobject: Add sanity check for kset->kobj.ktype in kset_register() Date: Wed, 20 Sep 2023 13:31:19 +0200 Message-ID: <20230920112843.240593473@linuxfoundation.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20230920112836.799946261@linuxfoundation.org> References: <20230920112836.799946261@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ 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 bbbb067de8ecd..b908655c58123 100644 --- a/lib/kobject.c +++ b/lib/kobject.c @@ -814,6 +814,11 @@ 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