From mboxrd@z Thu Jan 1 00:00:00 1970 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=-3.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,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 4B5D6C46471 for ; Tue, 7 Aug 2018 18:56:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 075282151D for ; Tue, 7 Aug 2018 18:56:47 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 075282151D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390504AbeHGVM1 (ORCPT ); Tue, 7 Aug 2018 17:12:27 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:33984 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732347AbeHGVM0 (ORCPT ); Tue, 7 Aug 2018 17:12:26 -0400 Received: from localhost (unknown [194.244.16.108]) by mail.linuxfoundation.org (Postfix) with ESMTPSA id D821ED0E; Tue, 7 Aug 2018 18:56:42 +0000 (UTC) From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Ganapathi Bhat , Kalle Valo , Sasha Levin Subject: [PATCH 3.18 17/85] mwifiex: handle race during mwifiex_usb_disconnect Date: Tue, 7 Aug 2018 20:51:19 +0200 Message-Id: <20180807172357.989751204@linuxfoundation.org> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20180807172357.357252052@linuxfoundation.org> References: <20180807172357.357252052@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ganapathi Bhat [ Upstream commit b817047ae70c0bd67b677b65d0d69d72cd6e9728 ] Race condition is observed during rmmod of mwifiex_usb: 1. The rmmod thread will call mwifiex_usb_disconnect(), download SHUTDOWN command and do wait_event_interruptible_timeout(), waiting for response. 2. The main thread will handle the response and will do a wake_up_interruptible(), unblocking rmmod thread. 3. On getting unblocked, rmmod thread will make rx_cmd.urb = NULL in mwifiex_usb_free(). 4. The main thread will try to resubmit rx_cmd.urb in mwifiex_usb_submit_rx_urb(), which is NULL. To fix, wait for main thread to complete before calling mwifiex_usb_free(). Signed-off-by: Ganapathi Bhat Signed-off-by: Kalle Valo Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/net/wireless/mwifiex/usb.c | 3 +++ 1 file changed, 3 insertions(+) --- a/drivers/net/wireless/mwifiex/usb.c +++ b/drivers/net/wireless/mwifiex/usb.c @@ -556,6 +556,9 @@ static void mwifiex_usb_disconnect(struc MWIFIEX_FUNC_SHUTDOWN); } + if (adapter->workqueue) + flush_workqueue(adapter->workqueue); + mwifiex_usb_free(card); dev_dbg(adapter->dev, "%s: removing card\n", __func__);