From patchwork Mon Feb 17 15:27:49 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hanno Zulla X-Patchwork-Id: 208180 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=-8.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_SANE_1 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 ABE46C34021 for ; Mon, 17 Feb 2020 15:27:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7E896208C4 for ; Mon, 17 Feb 2020 15:27:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=hanno.de header.i=@hanno.de header.b="CfA7MMRT" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726911AbgBQP1y (ORCPT ); Mon, 17 Feb 2020 10:27:54 -0500 Received: from www149.your-server.de ([78.47.15.70]:35408 "EHLO www149.your-server.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726528AbgBQP1x (ORCPT ); Mon, 17 Feb 2020 10:27:53 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=hanno.de; s=default1911; h=Content-Transfer-Encoding:Content-Type:In-Reply-To: MIME-Version:Date:Message-ID:References:To:From:Subject:Sender:Reply-To:Cc: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=wcHYCgvIc1V4L4eqgKkfizJKSrtKfmAWPhFBpvyI6bQ=; b=CfA7MMRTU9iH7WaHpY+SpuuLuS wTXycQngxf33BvZiH7nz/WRHkiRUmkZEaSSOzK3Vg82OuD0KXbwIMIono5wT4BCW3bDLmCzcnIWn6 Hw8gmHBlnkak3TwCNcC8bJrVwGhNqakK0nhRHer79drJ0t/2tRGH5Bt3GyzGdO5zOt1x2mM0GYYst qE72AZnmmqGYewTYW1oj/KDOj7mvQdOuO+m7FrCXxBXlIbah6fLIShjejJFIiYNVmb8vtAxfNe2l6 4HGb7wkdGdZT+ovAJbFGOf4coUJ58T4Mb+gG8zy67Gc93LU8YVi/f/NshVFmKVKhHIct4gDsp+R8f f3MstsZQ==; Received: from sslproxy06.your-server.de ([78.46.172.3]) by www149.your-server.de with esmtpsa (TLSv1.3:TLS_AES_256_GCM_SHA384:256) (Exim 4.92.3) (envelope-from ) id 1j3iJJ-0004sF-OY; Mon, 17 Feb 2020 16:27:49 +0100 Received: from [62.96.7.134] (helo=[10.1.0.41]) by sslproxy06.your-server.de with esmtpsa (TLSv1.3:TLS_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1j3iJJ-000GeY-Jh; Mon, 17 Feb 2020 16:27:49 +0100 Subject: [PATCH 3/3] HID: hid-bigbenff: fix race condition for scheduled work during removal From: Hanno Zulla To: Jiri Kosina , Benjamin Tissoires , linux-input@vger.kernel.org, linux-kernel@vger.kernel.org References: <798ec119-ce24-e1e3-17c9-b6018b04d75f@hanno.de> <1c355bbe-c0fb-395c-9050-346f87eb324c@hanno.de> Message-ID: <782af9b1-b648-bd21-b0f0-b0db22b8c0b7@hanno.de> Date: Mon, 17 Feb 2020 16:27:49 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.4.1 MIME-Version: 1.0 In-Reply-To: <1c355bbe-c0fb-395c-9050-346f87eb324c@hanno.de> Content-Language: de-DE X-Authenticated-Sender: abos@hanno.de X-Virus-Scanned: Clear (ClamAV 0.102.1/25726/Mon Feb 17 15:01:07 2020) Sender: linux-input-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-input@vger.kernel.org HID: hid-bigbenff: fix race condition for scheduled work during removal It's possible that there is scheduled work left while the device is already being removed, which can cause a kernel crash. Adding a flag will avoid this. Signed-off-by: Hanno Zulla --- drivers/hid/hid-bigbenff.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/hid/hid-bigbenff.c b/drivers/hid/hid-bigbenff.c index f8c552b64a89..db6da21ade06 100644 --- a/drivers/hid/hid-bigbenff.c +++ b/drivers/hid/hid-bigbenff.c @@ -174,6 +174,7 @@ static __u8 pid0902_rdesc_fixed[] = { struct bigben_device { struct hid_device *hid; struct hid_report *report; + bool removed; u8 led_state; /* LED1 = 1 .. LED4 = 8 */ u8 right_motor_on; /* right motor off/on 0/1 */ u8 left_motor_force; /* left motor force 0-255 */ @@ -190,6 +191,9 @@ static void bigben_worker(struct work_struct *work) struct bigben_device, worker); struct hid_field *report_field = bigben->report->field[0]; + if (bigben->removed) + return; + if (bigben->work_led) { bigben->work_led = false; report_field->value[0] = 0x01; /* 1 = led message */ @@ -304,6 +308,7 @@ static void bigben_remove(struct hid_device *hid) { struct bigben_device *bigben = hid_get_drvdata(hid); + bigben->removed = true; cancel_work_sync(&bigben->worker); hid_hw_stop(hid); } @@ -324,6 +329,7 @@ static int bigben_probe(struct hid_device *hid, return -ENOMEM; hid_set_drvdata(hid, bigben); bigben->hid = hid; + bigben->removed = false; error = hid_parse(hid); if (error) {