From nobody Mon Feb 9 21:38:24 2026 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 B714AEB64DD for ; Sat, 5 Aug 2023 08:42:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229602AbjHEIl7 (ORCPT ); Sat, 5 Aug 2023 04:41:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58670 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229534AbjHEIlu (ORCPT ); Sat, 5 Aug 2023 04:41:50 -0400 Received: from dggsgout12.his.huawei.com (unknown [45.249.212.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 25CA444B8 for ; Sat, 5 Aug 2023 01:41:48 -0700 (PDT) Received: from mail02.huawei.com (unknown [172.30.67.143]) by dggsgout12.his.huawei.com (SkyGuard) with ESMTP id 4RHwzp1NHpz4f3l7H for ; Sat, 5 Aug 2023 16:41:42 +0800 (CST) Received: from huaweicloud.com (unknown [10.174.178.55]) by APP4 (Coremail) with SMTP id gCh0CgAHuKtGC85kcXBwPg--.1103S5; Sat, 05 Aug 2023 16:41:44 +0800 (CST) From: thunder.leizhen@huaweicloud.com To: Greg Kroah-Hartman , "Rafael J . Wysocki" , linux-kernel@vger.kernel.org Cc: Zhen Lei Subject: [PATCH 1/2] kobject: Add sanity check for kset->kobj.ktype in kset_register() Date: Sat, 5 Aug 2023 16:41:13 +0800 Message-Id: <20230805084114.1298-2-thunder.leizhen@huaweicloud.com> X-Mailer: git-send-email 2.37.3.windows.1 In-Reply-To: <20230805084114.1298-1-thunder.leizhen@huaweicloud.com> References: <20230805084114.1298-1-thunder.leizhen@huaweicloud.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: gCh0CgAHuKtGC85kcXBwPg--.1103S5 X-Coremail-Antispam: 1UD129KBjvJXoW7KrWDKFW3Cr47uw45Zw13Jwb_yoW8Xr1UpF 4akF13trWrCr47Zw4DJF4kCry5XF1kuF4DurWYgw1Fqr4rKFWqgw13tr1kZF43urWxXFW2 qF10yws0v3yDAaDanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUU9mb4IE77IF4wAFF20E14v26r4j6ryUM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6r1S6rWUM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI8067AKxVWUGw A2048vs2IY020Ec7CjxVAFwI0_Jrv_JF4l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0rcxS w2x7M28EF7xvwVC0I7IYx2IY67AKxVW5JVW7JwA2z4x0Y4vE2Ix0cI8IcVCY1x0267AKxV W8Jr0_Cr1UM28EF7xvwVC2z280aVAFwI0_GcCE3s1l84ACjcxK6I8E87Iv6xkF7I0E14v2 6rxl6s0DM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F40Ex7xfMc Ij6xIIjxv20xvE14v26r1j6r18McIj6I8E87Iv67AKxVWUJVW8JwAm72CE4IkC6x0Yz7v_ Jr0_Gr1lF7xvr2IYc2Ij64vIr41lw4CEc2x0rVAKj4xxMxAIw28IcxkI7VAKI48JMxC20s 026xCaFVCjc4AY6r1j6r4UMI8I3I0E5I8CrVAFwI0_Jr0_Jr4lx2IqxVCjr7xvwVAFwI0_ JrI_JrWlx4CE17CEb7AF67AKxVWUAVWUtwCIc40Y0x0EwIxGrwCI42IY6xIIjxv20xvE14 v26r1j6r1xMIIF0xvE2Ix0cI8IcVCY1x0267AKxVWUJVW8JwCI42IY6xAIw20EY4v20xva j40_Jr0_JF4lIxAIcVC2z280aVAFwI0_Jr0_Gr1lIxAIcVC2z280aVCY1x0267AKxVW8Jr 0_Cr1UYxBIdaVFxhVjvjDU0xZFpf9x07UtsqAUUUUU= X-CM-SenderInfo: hwkx0vthuozvpl2kv046kxt4xhlfz01xgou0bp/ X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Zhen Lei When I register a kset in the following way: static struct kset my_kset; kobject_set_name(&my_kset.kobj, "my_kset"); ret =3D 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 --- lib/kobject.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/lib/kobject.c b/lib/kobject.c index 14e845209226ab8..72fa20f405f1520 100644 --- a/lib/kobject.c +++ b/lib/kobject.c @@ -861,6 +861,11 @@ int kset_register(struct kset *k) if (!k) return -EINVAL; =20 + if (!k->kobj.ktype) { + pr_err("must have a ktype to be initialized properly!\n"); + return -EINVAL; + } + kset_init(k); err =3D kobject_add_internal(&k->kobj); if (err) { --=20 2.34.1