From patchwork Fri Jun 10 12:17:58 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Linyu Yuan X-Patchwork-Id: 581112 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C23FFCCA481 for ; Fri, 10 Jun 2022 12:18:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1348865AbiFJMST (ORCPT ); Fri, 10 Jun 2022 08:18:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34118 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1348681AbiFJMSM (ORCPT ); Fri, 10 Jun 2022 08:18:12 -0400 Received: from alexa-out.qualcomm.com (alexa-out.qualcomm.com [129.46.98.28]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6C0C9273908; Fri, 10 Jun 2022 05:18:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; i=@quicinc.com; q=dns/txt; s=qcdkim; t=1654863491; x=1686399491; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=W2CKhP/5rS+ZfmpwCbDHWRP6kb6hCpDr3IH/jV3fbT0=; b=uBnrEJMG7EGEZKdjyIaednmfE0Dh066soOrxmx9yYqf9gSlqAQd72WhB lmFeZqrEui8MdnO+e9X9OGaTvN20AAVPdGSeS+Hw8iSMLt7SLcmeFiQTk mVIeo+2MKXFDSuAmGnFzIFeDReLJvjYrQl2Iy0Q4f6Vlxqgafv8c09SJh g=; Received: from ironmsg09-lv.qualcomm.com ([10.47.202.153]) by alexa-out.qualcomm.com with ESMTP; 10 Jun 2022 05:18:11 -0700 X-QCInternal: smtphost Received: from nasanex01c.na.qualcomm.com ([10.47.97.222]) by ironmsg09-lv.qualcomm.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Jun 2022 05:18:10 -0700 Received: from nalasex01b.na.qualcomm.com (10.47.209.197) by nasanex01c.na.qualcomm.com (10.47.97.222) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.986.22; Fri, 10 Jun 2022 05:18:10 -0700 Received: from linyyuan-gv.qualcomm.com (10.80.80.8) by nalasex01b.na.qualcomm.com (10.47.209.197) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.986.22; Fri, 10 Jun 2022 05:18:08 -0700 From: Linyu Yuan To: Felipe Balbi , Greg Kroah-Hartman CC: , , Jack Pham , Michael Wu , "John Keeping" , Linyu Yuan Subject: [PATCH v5 2/2] usb: gadget: f_fs: change ep->ep safe in ffs_epfile_io() Date: Fri, 10 Jun 2022 20:17:58 +0800 Message-ID: <1654863478-26228-3-git-send-email-quic_linyyuan@quicinc.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1654863478-26228-1-git-send-email-quic_linyyuan@quicinc.com> References: <1654863478-26228-1-git-send-email-quic_linyyuan@quicinc.com> MIME-Version: 1.0 X-Originating-IP: [10.80.80.8] X-ClientProxiedBy: nasanex01b.na.qualcomm.com (10.46.141.250) To nalasex01b.na.qualcomm.com (10.47.209.197) Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org In ffs_epfile_io(), when read/write data in blocking mode, it will wait the completion in interruptible mode, if task receive a signal, it will terminate the wait, at same time, if function unbind occurs, ffs_func_unbind() will kfree all eps, ffs_epfile_io() still try to dequeue request by dereferencing ep which may become invalid. Fix it by add ep spinlock and will not dereference ep if it is not valid. Cc: # 5.15 Reported-by: Michael Wu Tested-by: Michael Wu Reviewed-by: John Keeping Signed-off-by: Linyu Yuan --- v2: add Reviewed-by from John keeping v3: add Reported-by from Michael Wu v4: add Tested-by from Michael Wu cc stable kernel v5: no change drivers/usb/gadget/function/f_fs.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c index e1fcd8b..e0fa4b1 100644 --- a/drivers/usb/gadget/function/f_fs.c +++ b/drivers/usb/gadget/function/f_fs.c @@ -1080,6 +1080,11 @@ static ssize_t ffs_epfile_io(struct file *file, struct ffs_io_data *io_data) spin_unlock_irq(&epfile->ffs->eps_lock); if (wait_for_completion_interruptible(&io_data->done)) { + spin_lock_irq(&epfile->ffs->eps_lock); + if (epfile->ep != ep) { + ret = -ESHUTDOWN; + goto error_lock; + } /* * To avoid race condition with ffs_epfile_io_complete, * dequeue the request first then check @@ -1087,6 +1092,7 @@ static ssize_t ffs_epfile_io(struct file *file, struct ffs_io_data *io_data) * condition with req->complete callback. */ usb_ep_dequeue(ep->ep, req); + spin_unlock_irq(&epfile->ffs->eps_lock); wait_for_completion(&io_data->done); interrupted = io_data->status < 0; }