From patchwork Mon Mar 1 16:11:34 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 390173 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=-18.8 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, 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 A6105C433E0 for ; Mon, 1 Mar 2021 16:46:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6FDA164D9E for ; Mon, 1 Mar 2021 16:46:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233332AbhCAQqD (ORCPT ); Mon, 1 Mar 2021 11:46:03 -0500 Received: from mail.kernel.org ([198.145.29.99]:41542 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234878AbhCAQij (ORCPT ); Mon, 1 Mar 2021 11:38:39 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id B66E964F7E; Mon, 1 Mar 2021 16:27:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1614616063; bh=A8lt2b85apJASLVv9bUs5V/vytqUG/OE5vRNzANxHvk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=BvssY6fq0NOi4LsLAv6ruNEal5F6FjYqzGOAa6DFO4AEh/qQZgVaLhvbYGjyXscYw TosmHeaiyJ0AdAdx74lY49luVC93TqviZ5xF/Kei/WkGMPz/i+gWecAgrm9nB805Vf D+7NxQiEa0k33vbBVxJvTr/aDujtMdgiZTFHsmjc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Felipe Balbi , Jack Pham , Jerome Brunet , Sasha Levin , Ferry Toth , Peter Chen Subject: [PATCH 4.14 021/176] usb: gadget: u_audio: Free requests only after callback Date: Mon, 1 Mar 2021 17:11:34 +0100 Message-Id: <20210301161022.027433902@linuxfoundation.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210301161020.931630716@linuxfoundation.org> References: <20210301161020.931630716@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Jack Pham [ Upstream commit 7de8681be2cde9f6953d3be1fa6ce05f9fe6e637 ] 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 Reviewed-and-tested-by: Peter Chen Acked-by: Felipe Balbi Signed-off-by: Jack Pham Signed-off-by: Jerome Brunet Link: https://lore.kernel.org/r/20210118084642.322510-2-jbrunet@baylibre.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/usb/gadget/function/u_audio.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) diff --git a/drivers/usb/gadget/function/u_audio.c b/drivers/usb/gadget/function/u_audio.c index d3a639297e060..0370a1314b88a 100644 --- a/drivers/usb/gadget/function/u_audio.c +++ b/drivers/usb/gadget/function/u_audio.c @@ -98,7 +98,12 @@ 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; /* @@ -360,8 +365,14 @@ 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); + if (usb_ep_dequeue(ep, prm->ureq[i].req)) + usb_ep_free_request(ep, prm->ureq[i].req); + /* + * If usb_ep_dequeue() cannot successfully dequeue the + * request, the request will be freed by the completion + * callback. + */ + prm->ureq[i].req = NULL; } }