From patchwork Thu Jan 14 08:09:51 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thinh Nguyen X-Patchwork-Id: 12018849 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 637DEC433E9 for ; Thu, 14 Jan 2021 08:11:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2F69E233FD for ; Thu, 14 Jan 2021 08:11:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728020AbhANIKy (ORCPT ); Thu, 14 Jan 2021 03:10:54 -0500 Received: from smtprelay-out1.synopsys.com ([149.117.73.133]:53798 "EHLO smtprelay-out1.synopsys.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727155AbhANIKx (ORCPT ); Thu, 14 Jan 2021 03:10:53 -0500 Received: from mailhost.synopsys.com (sv1-mailhost2.synopsys.com [10.205.2.132]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by smtprelay-out1.synopsys.com (Postfix) with ESMTPS id 7FD5F40409; Thu, 14 Jan 2021 08:09:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=synopsys.com; s=mail; t=1610611793; bh=DYt3fzSUtsgqmE3RhzpKHDj+iN18zUya5J+pxlOZcEk=; h=Date:From:Subject:To:Cc:From; b=a5Wiq/SB3uBpQNmhY+LGcdlNBn+8uIt0M2Aclh9wcAy0Rsc56ipj17DYdj6zZy3wU saXtKbUByc9nqC4cflk/1fQcheNcksd/QbLRlbLwHelsC9l4oTCKZ9274RZK+cDYRj 2KsHaGI7Wr+OuS7WTe+5NYrXuoSRJV2wRhuRF9Du3lVWFDL82x7bChLe1BI/WOB5GV DVUO99ZpOVI2wyl2lH3gBeG/2aJUU42jTi72+yFrj/7tu92ZHlIOikDAE3D9Vve07f RpZSHNNWTWIi+w1AWTSDO8RLPtZp+cTtTHld116M7exOut4TqnRLgoI7x+16OjzifL YeEC3BITvIjOw== Received: from te-lab16 (unknown [10.10.52.11]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mailhost.synopsys.com (Postfix) with ESMTPSA id 371CEA0072; Thu, 14 Jan 2021 08:09:51 +0000 (UTC) Received: by te-lab16 (sSMTP sendmail emulation); Thu, 14 Jan 2021 00:09:51 -0800 Date: Thu, 14 Jan 2021 00:09:51 -0800 Message-Id: <338ea01fbd69b1985ef58f0f59af02c805ddf189.1610611437.git.Thinh.Nguyen@synopsys.com> X-SNPS-Relay: synopsys.com From: Thinh Nguyen Subject: [PATCH v3] usb: udc: core: Use lock when write to soft_connect To: Felipe Balbi , Greg Kroah-Hartman , linux-usb@vger.kernel.org, Peter Chen , Lee Jones , Alan Stern , Dejin Zheng , Sebastian Andrzej Siewior , "Ahmed S. Darwish" , Michal Nazarewicz Cc: stable@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org Use lock to guard against concurrent access for soft-connect/disconnect operations when writing to soft_connect sysfs. Cc: stable@vger.kernel.org Fixes: 2ccea03a8f7e ("usb: gadget: introduce UDC Class") Signed-off-by: Thinh Nguyen Acked-by: Felipe Balbi --- Changes in v3: - Improve flow: avoid assigning "ret = n" early Changes in v2: - Consolidate mutex_unlock to a single place using "goto out" drivers/usb/gadget/udc/core.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) base-commit: 4e0dcf62ab4cf917d0cbe751b8bf229a065248d4 diff --git a/drivers/usb/gadget/udc/core.c b/drivers/usb/gadget/udc/core.c index 6a62bbd01324..ea114f922ccf 100644 --- a/drivers/usb/gadget/udc/core.c +++ b/drivers/usb/gadget/udc/core.c @@ -1529,10 +1529,13 @@ static ssize_t soft_connect_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t n) { struct usb_udc *udc = container_of(dev, struct usb_udc, dev); + ssize_t ret; + mutex_lock(&udc_lock); if (!udc->driver) { dev_err(dev, "soft-connect without a gadget driver\n"); - return -EOPNOTSUPP; + ret = -EOPNOTSUPP; + goto out; } if (sysfs_streq(buf, "connect")) { @@ -1543,10 +1546,14 @@ static ssize_t soft_connect_store(struct device *dev, usb_gadget_udc_stop(udc); } else { dev_err(dev, "unsupported command '%s'\n", buf); - return -EINVAL; + ret = -EINVAL; + goto out; } - return n; + ret = n; +out: + mutex_unlock(&udc_lock); + return ret; } static DEVICE_ATTR_WO(soft_connect);