From patchwork Mon May 31 13:13:39 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 451019 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=-19.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT 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 E1FE4C47096 for ; Mon, 31 May 2021 14:21:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CEB1761408 for ; Mon, 31 May 2021 14:21:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233450AbhEaOXZ (ORCPT ); Mon, 31 May 2021 10:23:25 -0400 Received: from mail.kernel.org ([198.145.29.99]:43304 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233083AbhEaORj (ORCPT ); Mon, 31 May 2021 10:17:39 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 08190619A8; Mon, 31 May 2021 13:43:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1622468621; bh=jiGlot0zVWrzzRPERQIkJbnbZREjL7ezFimv9H6oI/o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=tlA3YTjUeSEF/1Y0S6JAq8uKxGtYrjI5V8T2wZvInNaYP40AxBgRFGHQRVqU2hTyc SLaPC0sMIswglbhpbXcK9kyB/tPXLzNf5v+53GpjLCfuYCXxvMBm9s78fKM+AU7t+r Qk0J0Oe0BRwrh/ApUyC2qEHbuXSHGn7ke0QDIqRY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Yoshihiro Shimoda Subject: [PATCH 5.4 062/177] usb: gadget: udc: renesas_usb3: Fix a race in usb3_start_pipen() Date: Mon, 31 May 2021 15:13:39 +0200 Message-Id: <20210531130650.046938260@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210531130647.887605866@linuxfoundation.org> References: <20210531130647.887605866@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Yoshihiro Shimoda commit e752dbc59e1241b13b8c4f7b6eb582862e7668fe upstream. The usb3_start_pipen() is called by renesas_usb3_ep_queue() and usb3_request_done_pipen() so that usb3_start_pipen() is possible to cause a race when getting usb3_first_req like below: renesas_usb3_ep_queue() spin_lock_irqsave() list_add_tail() spin_unlock_irqrestore() usb3_start_pipen() usb3_first_req = usb3_get_request() --- [1] --- interrupt --- usb3_irq_dma_int() usb3_request_done_pipen() usb3_get_request() usb3_start_pipen() usb3_first_req = usb3_get_request() ... (the req is possible to be finished in the interrupt) The usb3_first_req [1] above may have been finished after the interrupt ended so that this driver caused to start a transfer wrongly. To fix this issue, getting/checking the usb3_first_req are under spin_lock_irqsave() in the same section. Fixes: 746bfe63bba3 ("usb: gadget: renesas_usb3: add support for Renesas USB3.0 peripheral controller") Cc: stable Signed-off-by: Yoshihiro Shimoda Link: https://lore.kernel.org/r/20210524060155.1178724-1-yoshihiro.shimoda.uh@renesas.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/gadget/udc/renesas_usb3.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) --- a/drivers/usb/gadget/udc/renesas_usb3.c +++ b/drivers/usb/gadget/udc/renesas_usb3.c @@ -1473,7 +1473,7 @@ static void usb3_start_pipen(struct rene struct renesas_usb3_request *usb3_req) { struct renesas_usb3 *usb3 = usb3_ep_to_usb3(usb3_ep); - struct renesas_usb3_request *usb3_req_first = usb3_get_request(usb3_ep); + struct renesas_usb3_request *usb3_req_first; unsigned long flags; int ret = -EAGAIN; u32 enable_bits = 0; @@ -1481,7 +1481,8 @@ static void usb3_start_pipen(struct rene spin_lock_irqsave(&usb3->lock, flags); if (usb3_ep->halt || usb3_ep->started) goto out; - if (usb3_req != usb3_req_first) + usb3_req_first = __usb3_get_request(usb3_ep); + if (!usb3_req_first || usb3_req != usb3_req_first) goto out; if (usb3_pn_change(usb3, usb3_ep->num) < 0)