From patchwork Tue Oct 27 23:31:38 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jack Pham X-Patchwork-Id: 11862283 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 825FF92C for ; Wed, 28 Oct 2020 01:38:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5875B21D41 for ; Wed, 28 Oct 2020 01:38:38 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=mg.codeaurora.org header.i=@mg.codeaurora.org header.b="YSXGpCBE" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726137AbgJ1Big (ORCPT ); Tue, 27 Oct 2020 21:38:36 -0400 Received: from m42-4.mailgun.net ([69.72.42.4]:29587 "EHLO m42-4.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1833012AbgJ0XcO (ORCPT ); Tue, 27 Oct 2020 19:32:14 -0400 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1603841534; h=Content-Transfer-Encoding: MIME-Version: Message-Id: Date: Subject: Cc: To: From: Sender; bh=3Y4SeRGOZRE5ONISVbAv/kcnLqyx4oqMlOn/FDMG1vE=; b=YSXGpCBEXserp+UvmRW2TV4XnzdCAGedSvsY1FJmlpJdBUb6PYU2MvVMYPnNBu1XaCCYn3OD 8jpP5gmGww/ckPJrpwhVOw+t0Qhsq/f6RgHOpvBkZ9RWWQ4j+tacO7CfFX33LM4YlQvLPjiP tcR65ypnxLY2g69RcJ9a+KKNWy4= X-Mailgun-Sending-Ip: 69.72.42.4 X-Mailgun-Sid: WyIxZTE2YSIsICJsaW51eC11c2JAdmdlci5rZXJuZWwub3JnIiwgImJlOWU0YSJd Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n01.prod.us-west-2.postgun.com with SMTP id 5f98adec09df41a6c456ac64 (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Tue, 27 Oct 2020 23:31:56 GMT Sender: jackp=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 5C45DC433CB; Tue, 27 Oct 2020 23:31:56 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-caf-mail-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=ALL_TRUSTED,BAYES_00,SPF_FAIL, URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from jackp-linux.qualcomm.com (i-global254.qualcomm.com [199.106.103.254]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: jackp) by smtp.codeaurora.org (Postfix) with ESMTPSA id 29E75C433CB; Tue, 27 Oct 2020 23:31:55 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 29E75C433CB Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; spf=fail smtp.mailfrom=jackp@codeaurora.org From: Jack Pham To: Felipe Balbi , Ruslan Bilovol Cc: Greg Kroah-Hartman , Thinh Nguyen , Andy Shevchenko , linux-usb@vger.kernel.org, Jack Pham , Ferry Toth Subject: [PATCH] usb: gadget: audio: Free requests only after callback Date: Tue, 27 Oct 2020 16:31:38 -0700 Message-Id: <20201027233138.13712-1-jackp@codeaurora.org> X-Mailer: git-send-email 2.24.0 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org As per the kernel doc for usb_ep_dequeue(), it states that "this routine is asynchronous, that is, it may return before the completion routine runs". And indeed since v5.0 the dwc3 gadget driver updated its behavior to place dequeued requests on to a cancelled list to be given back later after the endpoint is stopped. The free_ep() was incorrectly assuming that a request was ready to be freed after calling dequeue which results in a use-after-free in dwc3 when it traverses its cancelled list. Fix this by moving the usb_ep_free_request() call to the callback itself in case the ep is disabled. Fixes: eb9fecb9e69b0 ("usb: gadget: f_uac2: split out audio core") Reported-and-tested-by: Ferry Toth Signed-off-by: Jack Pham --- drivers/usb/gadget/function/u_audio.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/usb/gadget/function/u_audio.c b/drivers/usb/gadget/function/u_audio.c index e6d32c536781..a3b557fad1fd 100644 --- a/drivers/usb/gadget/function/u_audio.c +++ b/drivers/usb/gadget/function/u_audio.c @@ -89,7 +89,12 @@ static void u_audio_iso_complete(struct usb_ep *ep, struct usb_request *req) struct snd_uac_chip *uac = prm->uac; /* i/f shutting down */ - if (!prm->ep_enabled || req->status == -ESHUTDOWN) + if (!prm->ep_enabled) { + usb_ep_free_request(ep, req); + return; + } + + if (req->status == -ESHUTDOWN) return; /* @@ -337,7 +342,6 @@ static inline void free_ep(struct uac_rtd_params *prm, struct usb_ep *ep) for (i = 0; i < params->req_number; i++) { if (prm->ureq[i].req) { usb_ep_dequeue(ep, prm->ureq[i].req); - usb_ep_free_request(ep, prm->ureq[i].req); prm->ureq[i].req = NULL; } }