From patchwork Wed Nov 23 13:28:08 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yang Yingliang X-Patchwork-Id: 13053666 X-Patchwork-Delegate: kuba@kernel.org 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 47B83C433FE for ; Wed, 23 Nov 2022 13:42:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236245AbiKWNm3 (ORCPT ); Wed, 23 Nov 2022 08:42:29 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55162 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238852AbiKWNmB (ORCPT ); Wed, 23 Nov 2022 08:42:01 -0500 Received: from szxga08-in.huawei.com (szxga08-in.huawei.com [45.249.212.255]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 240AE7CBAC for ; Wed, 23 Nov 2022 05:30:15 -0800 (PST) Received: from dggpemm500021.china.huawei.com (unknown [172.30.72.56]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4NHMRp3hRDz15Mly; Wed, 23 Nov 2022 21:29:42 +0800 (CST) Received: from dggpemm500007.china.huawei.com (7.185.36.183) by dggpemm500021.china.huawei.com (7.185.36.109) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Wed, 23 Nov 2022 21:30:13 +0800 Received: from huawei.com (10.175.103.91) by dggpemm500007.china.huawei.com (7.185.36.183) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Wed, 23 Nov 2022 21:30:12 +0800 From: Yang Yingliang To: CC: , , , , , , , , Subject: [PATCH net] net: phy: fix null-ptr-deref while probe() failed Date: Wed, 23 Nov 2022 21:28:08 +0800 Message-ID: <20221123132808.2090427-1-yangyingliang@huawei.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 X-Originating-IP: [10.175.103.91] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To dggpemm500007.china.huawei.com (7.185.36.183) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org I got a null-ptr-deref report as following when doing fault injection test: BUG: kernel NULL pointer dereference, address: 0000000000000058 Oops: 0000 [#1] PREEMPT SMP KASAN PTI CPU: 1 PID: 253 Comm: 507-spi-dm9051 Tainted: G B N 6.1.0-rc3+ Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 RIP: 0010:klist_put+0x2d/0xd0 Call Trace: klist_remove+0xf1/0x1c0 device_release_driver_internal+0x23e/0x2d0 bus_remove_device+0x1bd/0x240 device_del+0x357/0x770 phy_device_remove+0x11/0x30 mdiobus_unregister+0xa5/0x140 release_nodes+0x6a/0xa0 devres_release_all+0xf8/0x150 device_unbind_cleanup+0x19/0xd0 //probe path: phy_device_register() device_add() phy_connect phy_attach_direct() //set device driver probe() //it's failed, driver is not bound device_bind_driver() // probe failed, it's not called //remove path: phy_device_remove() device_del() device_release_driver_internal() __device_release_driver() //dev->drv is not NULL klist_remove() <- knode_driver is not added yet, cause null-ptr-deref In phy_attach_direct(), after setting the 'dev->driver', probe() fails, device_bind_driver() is not called, so the knode_driver->n_klist is not set, then it causes null-ptr-deref in __device_release_driver() while deleting device. Fix this by setting dev->driver to NULL in the error path in phy_attach_direct(). Fixes: e13934563db0 ("[PATCH] PHY Layer fixup") Signed-off-by: Yang Yingliang --- drivers/net/phy/phy_device.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c index 57849ac0384e..a72adabfd2a7 100644 --- a/drivers/net/phy/phy_device.c +++ b/drivers/net/phy/phy_device.c @@ -1520,6 +1520,7 @@ int phy_attach_direct(struct net_device *dev, struct phy_device *phydev, error_module_put: module_put(d->driver->owner); + d->driver = NULL; error_put_device: put_device(d); if (ndev_owner != bus->owner)