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 41625EEB57A for ; Sat, 9 Sep 2023 00:44:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231760AbjIIAoq (ORCPT ); Fri, 8 Sep 2023 20:44:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55832 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239148AbjIIAoK (ORCPT ); Fri, 8 Sep 2023 20:44:10 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8101C44BB; Fri, 8 Sep 2023 17:41:30 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 43529C116AD; Sat, 9 Sep 2023 00:41:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1694220074; bh=h9hr9675zwbHgx9IvJpYZTExERs50tDCPS5XM22kAQo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=LMPb6RNPgxfMmph3tyZztrloCaqsDSA22VkX/dX9IplA12mE34ypWRWi8OQitZs9a V4BnCZlqrKKeRVDclISy6yfxVRMjXCQf05K40M51M5cdvgYWmh3UX8nwnLnc4ZbhUC qGQwFEE/4zc33Ycd8g/u3+DS+pg+rTxUQkNmUqbtS4NssUQblgiGCXRd9xJH+CWHk/ T9rQaPhgSKOuoDZlkpFWjT3TPgIZjRsPJrF0g3eOReLS2Ef8Wj6zAZGcLm2+qvRuQX O/64I+ykenNwiUPbB4tUsAre4h3txZVJIoVhT+XpjHEJnbK3zBPw9HCxQ+8DN0AKv9 aoIpweR69RSew== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Zhen Lei , Greg Kroah-Hartman , Sasha Levin Subject: [PATCH AUTOSEL 4.19 14/14] kobject: Add sanity check for kset->kobj.ktype in kset_register() Date: Fri, 8 Sep 2023 20:40:45 -0400 Message-Id: <20230909004045.3581014-14-sashal@kernel.org> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230909004045.3581014-1-sashal@kernel.org> References: <20230909004045.3581014-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 4.19.294 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@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 97d86dc17c42b..2bab65232925a 100644 --- a/lib/kobject.c +++ b/lib/kobject.c @@ -829,6 +829,11 @@ 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