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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2802CC433FE for ; Mon, 4 Oct 2021 13:08:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0F96B61BA9 for ; Mon, 4 Oct 2021 13:08:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235357AbhJDNKS (ORCPT ); Mon, 4 Oct 2021 09:10:18 -0400 Received: from mail.kernel.org ([198.145.29.99]:39514 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235157AbhJDNHp (ORCPT ); Mon, 4 Oct 2021 09:07:45 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 445BA613A8; Mon, 4 Oct 2021 13:01:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1633352512; bh=Rs3Vcciiab+UuXssMClhbU/oEVDVBzV1cge3WXf6soM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=E857S6SrMiXvogquHm0oPVaHU04B74MZ0gaYi7kcIgXC32cghBWg84ZUQknz2gsRy swj/aVWiM+BlBEmqNk4uKdM1CtTNmCNAK5Or9BGL6bp08PK9I8/pPMZcaaGuzRLvmI nhjTBjZHlL+/6+F1NadfAH6kB0VYAuc6Eyj3WBTY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dan Carpenter , Johannes Thumshirn Subject: [PATCH 4.19 16/95] mcb: fix error handling in mcb_alloc_bus() Date: Mon, 4 Oct 2021 14:51:46 +0200 Message-Id: <20211004125034.088348054@linuxfoundation.org> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20211004125033.572932188@linuxfoundation.org> References: <20211004125033.572932188@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Dan Carpenter commit 25a1433216489de4abc889910f744e952cb6dbae upstream. There are two bugs: 1) If ida_simple_get() fails then this code calls put_device(carrier) but we haven't yet called get_device(carrier) and probably that leads to a use after free. 2) After device_initialize() then we need to use put_device() to release the bus. This will free the internal resources tied to the device and call mcb_free_bus() which will free the rest. Fixes: 5d9e2ab9fea4 ("mcb: Implement bus->dev.release callback") Fixes: 18d288198099 ("mcb: Correctly initialize the bus's device") Cc: stable@vger.kernel.org Signed-off-by: Dan Carpenter Signed-off-by: Johannes Thumshirn Link: https://lore.kernel.org/r/32e160cf6864ce77f9d62948338e24db9fd8ead9.1630931319.git.johannes.thumshirn@wdc.com Signed-off-by: Greg Kroah-Hartman --- drivers/mcb/mcb-core.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) --- a/drivers/mcb/mcb-core.c +++ b/drivers/mcb/mcb-core.c @@ -280,8 +280,8 @@ struct mcb_bus *mcb_alloc_bus(struct dev bus_nr = ida_simple_get(&mcb_ida, 0, 0, GFP_KERNEL); if (bus_nr < 0) { - rc = bus_nr; - goto err_free; + kfree(bus); + return ERR_PTR(bus_nr); } bus->bus_nr = bus_nr; @@ -296,12 +296,12 @@ struct mcb_bus *mcb_alloc_bus(struct dev dev_set_name(&bus->dev, "mcb:%d", bus_nr); rc = device_add(&bus->dev); if (rc) - goto err_free; + goto err_put; return bus; -err_free: - put_device(carrier); - kfree(bus); + +err_put: + put_device(&bus->dev); return ERR_PTR(rc); } EXPORT_SYMBOL_GPL(mcb_alloc_bus);