Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753293AbdGYTX1 (ORCPT ); Tue, 25 Jul 2017 15:23:27 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:35314 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751975AbdGYTXZ (ORCPT ); Tue, 25 Jul 2017 15:23:25 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Vincent Cuissard , Johan Hovold , Samuel Ortiz Subject: [PATCH 4.12 012/196] NFC: nfcmrvl: do not use device-managed resources Date: Tue, 25 Jul 2017 12:20:11 -0700 Message-Id: <20170725192046.903283056@linuxfoundation.org> X-Mailer: git-send-email 2.13.3 In-Reply-To: <20170725192046.422343510@linuxfoundation.org> References: <20170725192046.422343510@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2950 Lines: 90 4.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Johan Hovold commit 0cbe40112f42cf5e008f9127f6cd5952ba3946c7 upstream. This specifically fixes resource leaks in the registration error paths. Device-managed resources is a bad fit for this driver as devices can be registered from the n_nci line discipline. Firstly, a tty may not even have a corresponding device (should it be part of a Unix98 pty) something which would lead to a NULL-pointer dereference when registering resources. Secondly, if the tty has a class device, its lifetime exceeds that of the line discipline, which means that resources would leak every time the line discipline is closed (or if registration fails). Currently, the devres interface was only being used to request a reset gpio despite the fact that it was already explicitly freed in nfcmrvl_nci_unregister_dev() (along with the private data), something which also prevented the resource leak at close. Note that the driver treats gpio number 0 as invalid despite it being perfectly valid. This will be addressed in a follow-up patch. Fixes: b2fe288eac72 ("NFC: nfcmrvl: free reset gpio") Fixes: 4a2b947f56b3 ("NFC: nfcmrvl: add chip reset management") Cc: Vincent Cuissard Signed-off-by: Johan Hovold Signed-off-by: Samuel Ortiz Signed-off-by: Greg Kroah-Hartman --- drivers/nfc/nfcmrvl/main.c | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-) --- a/drivers/nfc/nfcmrvl/main.c +++ b/drivers/nfc/nfcmrvl/main.c @@ -124,12 +124,13 @@ struct nfcmrvl_private *nfcmrvl_nci_regi memcpy(&priv->config, pdata, sizeof(*pdata)); if (priv->config.reset_n_io) { - rc = devm_gpio_request_one(dev, - priv->config.reset_n_io, - GPIOF_OUT_INIT_LOW, - "nfcmrvl_reset_n"); - if (rc < 0) + rc = gpio_request_one(priv->config.reset_n_io, + GPIOF_OUT_INIT_LOW, + "nfcmrvl_reset_n"); + if (rc < 0) { + priv->config.reset_n_io = 0; nfc_err(dev, "failed to request reset_n io\n"); + } } if (phy == NFCMRVL_PHY_SPI) { @@ -154,7 +155,7 @@ struct nfcmrvl_private *nfcmrvl_nci_regi if (!priv->ndev) { nfc_err(dev, "nci_allocate_device failed\n"); rc = -ENOMEM; - goto error; + goto error_free_gpio; } nci_set_drvdata(priv->ndev, priv); @@ -179,7 +180,9 @@ struct nfcmrvl_private *nfcmrvl_nci_regi error_free_dev: nci_free_device(priv->ndev); -error: +error_free_gpio: + if (priv->config.reset_n_io) + gpio_free(priv->config.reset_n_io); kfree(priv); return ERR_PTR(rc); } @@ -195,7 +198,7 @@ void nfcmrvl_nci_unregister_dev(struct n nfcmrvl_fw_dnld_deinit(priv); if (priv->config.reset_n_io) - devm_gpio_free(priv->dev, priv->config.reset_n_io); + gpio_free(priv->config.reset_n_io); nci_unregister_device(ndev); nci_free_device(ndev);