From nobody Tue Jun 23 15:11:13 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 3A2E0C433FE for ; Thu, 3 Mar 2022 01:46:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231476AbiCCBq4 (ORCPT ); Wed, 2 Mar 2022 20:46:56 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52188 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231445AbiCCBqx (ORCPT ); Wed, 2 Mar 2022 20:46:53 -0500 X-Greylist: delayed 914 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Wed, 02 Mar 2022 17:46:07 PST Received: from mail-m974.mail.163.com (mail-m974.mail.163.com [123.126.97.4]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 67AC21B6E18; Wed, 2 Mar 2022 17:46:07 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:Subject:Date:Message-Id:MIME-Version; bh=XAi7D k9Yg7EF/mSMo8raLyxYjVznmUNk90i0YbDYo5A=; b=ZEmq/qzrJtrY9zC207PgZ REzIQycl5G5Qj/X4NlmoD0WDcQJJIo/2XwUaDq+pebvUyOZ0q/RK6IWhS58FaZaj NLHKooZXW2WFd1/q87NjPrpNq51uyfD7UAx3EZeW/lM1eAo2Q/pFkztOqoXHwAnJ FqL/lfJ8JYmk+SV6qQxKps= Received: from localhost.localdomain (unknown [218.106.182.227]) by smtp4 (Coremail) with SMTP id HNxpCgBnPKQzGiBi+_cuEw--.7369S4; Thu, 03 Mar 2022 09:30:37 +0800 (CST) From: Jianglei Nie To: davem@davemloft.net, kuba@kernel.org, caihuoqing@baidu.com Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Jianglei Nie Subject: [PATCH] net: arc_emac: Fix use after free in arc_mdio_probe() Date: Thu, 3 Mar 2022 09:30:22 +0800 Message-Id: <20220303013022.459154-1-niejianglei2021@163.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: HNxpCgBnPKQzGiBi+_cuEw--.7369S4 X-Coremail-Antispam: 1Uf129KBjvdXoW7Gw45KFyDGF47urW7GrW3Wrg_yoWDZFgE9w 18Za43Jw43tr90gw4j9F4ayryvk3yUXrs3uF4fKr9xAr9rCr47X3WkuF93Jr1kuws2qF9I qayayrW7u348KjkaLaAFLSUrUUUUUb8apTn2vfkv8UJUUUU8Yxn0WfASr-VFAUDa7-sFnT 9fnUUvcSsGvfC2KfnxnUUI43ZEXa7xREzuWtUUUUU== X-Originating-IP: [218.106.182.227] X-CM-SenderInfo: xqlhyxxdqjzvrlsqjii6rwjhhfrp/1tbiQx24jFc7XpwVewAAsq Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" If bus->state is equal to MDIOBUS_ALLOCATED, mdiobus_free(bus) will free the "bus". But bus->name is still used in the next line, which will lead to a use after free. We can fix it by assigning dev_err_probe() to dev_err before the bus is freed to avoid the uaf. Signed-off-by: Jianglei Nie --- drivers/net/ethernet/arc/emac_mdio.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/arc/emac_mdio.c b/drivers/net/ethernet/ar= c/emac_mdio.c index 9acf589b1178..795a25c5848a 100644 --- a/drivers/net/ethernet/arc/emac_mdio.c +++ b/drivers/net/ethernet/arc/emac_mdio.c @@ -165,9 +165,10 @@ int arc_mdio_probe(struct arc_emac_priv *priv) =20 error =3D of_mdiobus_register(bus, priv->dev->of_node); if (error) { - mdiobus_free(bus); - return dev_err_probe(priv->dev, error, + int dev_err =3D dev_err_probe(priv->dev, error, "cannot register MDIO bus %s\n", bus->name); + mdiobus_free(bus); + return dev_err; } =20 return 0; --=20 2.25.1