From patchwork Tue Dec 13 12:56:14 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: lizetao X-Patchwork-Id: 13071964 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 78888C4332F for ; Tue, 13 Dec 2022 11:52:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235307AbiLMLwF (ORCPT ); Tue, 13 Dec 2022 06:52:05 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46532 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234707AbiLMLwD (ORCPT ); Tue, 13 Dec 2022 06:52:03 -0500 Received: from szxga08-in.huawei.com (szxga08-in.huawei.com [45.249.212.255]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BCB94FAF2; Tue, 13 Dec 2022 03:52:01 -0800 (PST) Received: from kwepemi500012.china.huawei.com (unknown [172.30.72.53]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4NWcJl1072z15NJj; Tue, 13 Dec 2022 19:51:03 +0800 (CST) Received: from huawei.com (10.175.101.6) by kwepemi500012.china.huawei.com (7.221.188.12) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.34; Tue, 13 Dec 2022 19:51:59 +0800 From: Li Zetao To: CC: , , , , , , , Subject: [PATCH net v2] r6040: Fix kmemleak in probe and remove Date: Tue, 13 Dec 2022 20:56:14 +0800 Message-ID: <20221213125614.927754-1-lizetao1@huawei.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <7f35ca55-cbed-98ac-4988-1b783db21dc5@huawei.com> References: <7f35ca55-cbed-98ac-4988-1b783db21dc5@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.101.6] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To kwepemi500012.china.huawei.com (7.221.188.12) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org There is a memory leaks reported by kmemleak: unreferenced object 0xffff888116111000 (size 2048): comm "modprobe", pid 817, jiffies 4294759745 (age 76.502s) hex dump (first 32 bytes): 00 c4 0a 04 81 88 ff ff 08 10 11 16 81 88 ff ff ................ 08 10 11 16 81 88 ff ff 00 00 00 00 00 00 00 00 ................ backtrace: [] kmalloc_trace+0x22/0x60 [] phy_device_create+0x4e/0x90 [] get_phy_device+0xd2/0x220 [] mdiobus_scan+0xa4/0x2e0 [] __mdiobus_register+0x482/0x8b0 [] r6040_init_one+0x714/0xd2c [r6040] ... The problem occurs in probe process as follows: r6040_init_one: mdiobus_register mdiobus_scan <- alloc and register phy_device, the reference count of phy_device is 3 r6040_mii_probe phy_connect <- connect to the first phy_device, so the reference count of the first phy_device is 4, others are 3 register_netdev <- fault inject succeeded, goto error handling path // error handling path err_out_mdio_unregister: mdiobus_unregister(lp->mii_bus); err_out_mdio: mdiobus_free(lp->mii_bus); <- the reference count of the first phy_device is 1, it is not released and other phy_devices are released // similarly, the remove process also has the same problem The root cause is traced to the phy_device is not disconnected when removes one r6040 device in r6040_remove_one() or on error handling path after r6040_mii probed successfully. In r6040_mii_probe(), a net ethernet device is connected to the first PHY device of mii_bus, in order to notify the connected driver when the link status changes, which is the default behavior of the PHY infrastructure to handle everything. Therefore the phy_device should be disconnected when removes one r6040 device or on error handling path. Fix it by adding phy_disconnect() when removes one r6040 device or on error handling path after r6040_mii probed successfully. Fixes: 3831861b4ad8 ("r6040: implement phylib") Signed-off-by: Li Zetao Reviewed-by: Leon Romanovsky --- v1 -> v2: change the subject prefix "PATCH" to "PATCH net" and change the goto label name "err_out_r6040_mii_remove" to "err_out_phy_disconnect" drivers/net/ethernet/rdc/r6040.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/rdc/r6040.c b/drivers/net/ethernet/rdc/r6040.c index eecd52ed1ed2..f4d434c379e7 100644 --- a/drivers/net/ethernet/rdc/r6040.c +++ b/drivers/net/ethernet/rdc/r6040.c @@ -1159,10 +1159,12 @@ static int r6040_init_one(struct pci_dev *pdev, const struct pci_device_id *ent) err = register_netdev(dev); if (err) { dev_err(&pdev->dev, "Failed to register net device\n"); - goto err_out_mdio_unregister; + goto err_out_phy_disconnect; } return 0; +err_out_phy_disconnect: + phy_disconnect(dev->phydev); err_out_mdio_unregister: mdiobus_unregister(lp->mii_bus); err_out_mdio: @@ -1186,6 +1188,7 @@ static void r6040_remove_one(struct pci_dev *pdev) struct r6040_private *lp = netdev_priv(dev); unregister_netdev(dev); + phy_disconnect(dev->phydev); mdiobus_unregister(lp->mii_bus); mdiobus_free(lp->mii_bus); netif_napi_del(&lp->napi);