From patchwork Tue Oct 10 10:20:27 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hans de Goede X-Patchwork-Id: 733032 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 1B770CD80A1 for ; Tue, 10 Oct 2023 10:22:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230503AbjJJKV7 (ORCPT ); Tue, 10 Oct 2023 06:21:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58136 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230483AbjJJKV6 (ORCPT ); Tue, 10 Oct 2023 06:21:58 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DE25DAF for ; Tue, 10 Oct 2023 03:21:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1696933267; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=/tVr/izul10Iw2LV2X+wvtXF+u95KNN6Rzd+SQqZxB0=; b=GbWUMxCMZntCCs7e+vmnHZGDq2AvlS2RGhYuIXMimI9aD3UWaXAYPiOfWtyAnLFrE5QusL ErMOf01RCwiKRRStWZnsOonmL6V7eZ+bTLH+kCRL72Bv30QY2XjUZax/ai664zXeQ7kaqa IkTn4l6ddFfC5zxzgu34+R7KVLw/y58= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-628-ocDEz45SPH6YqvhdGQfelg-1; Tue, 10 Oct 2023 06:20:48 -0400 X-MC-Unique: ocDEz45SPH6YqvhdGQfelg-1 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id A3E2F80CDA1; Tue, 10 Oct 2023 10:20:47 +0000 (UTC) Received: from localhost.localdomain (unknown [10.39.194.20]) by smtp.corp.redhat.com (Postfix) with ESMTP id BAB9640BAED; Tue, 10 Oct 2023 10:20:46 +0000 (UTC) From: Hans de Goede To: =?utf-8?q?Filipe_La=C3=ADns?= , Bastien Nocera , Jiri Kosina , Benjamin Tissoires Cc: Hans de Goede , linux-input@vger.kernel.org Subject: [PATCH v3 10/12] HID: logitech-hidpp: Fix connect event race Date: Tue, 10 Oct 2023 12:20:27 +0200 Message-ID: <20231010102029.111003-11-hdegoede@redhat.com> In-Reply-To: <20231010102029.111003-1-hdegoede@redhat.com> References: <20231010102029.111003-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.9 Precedence: bulk List-ID: X-Mailing-List: linux-input@vger.kernel.org There is a connect event race in hidpp_probe() in these 2 lines: connected = hidpp_root_get_protocol_version(hidpp) == 0; atomic_set(&hidpp->connected, connected); Specifically the following can happen: 1. This line from hidpp_probe() is executed: connected = hidpp_root_get_protocol_version(hidpp) == 0; and sets connected to false; 2. A connect-event packet is received and does: atomic_set(&hidpp->connected, true); 3. The next line from hidpp_probe() is executed: atomic_set(&hidpp->connected, connected); and sets the atomic_t back to 0 again. 4. hidpp_connect_event() runs and sees the connected device as disconnected because of this. To fix this make hidpp_connect_event() query the connection status of the device itself instead of having it rely on possibly stale data cached in struct hidpp_device. This series has been tested on the following devices: Logitech Bluetooth Laser Travel Mouse (bluetooth, HID++ 1.0) Logitech M720 Triathlon (bluetooth, HID++ 4.5) Logitech M720 Triathlon (unifying, HID++ 4.5) Logitech K400 Pro (unifying, HID++ 4.1) Logitech K270 (eQUAD nano Lite, HID++ 2.0) Logitech M185 (eQUAD nano Lite, HID++ 4.5) Logitech LX501 keyboard (27 Mhz, HID++ builtin scroll-wheel, HID++ 1.0) Logitech M-RAZ105 mouse (27 Mhz, HID++ extra mouse buttons, HID++ 1.0) Signed-off-by: Hans de Goede --- drivers/hid/hid-logitech-hidpp.c | 25 +++++-------------------- 1 file changed, 5 insertions(+), 20 deletions(-) diff --git a/drivers/hid/hid-logitech-hidpp.c b/drivers/hid/hid-logitech-hidpp.c index e945e4e8180f..4793a3236f17 100644 --- a/drivers/hid/hid-logitech-hidpp.c +++ b/drivers/hid/hid-logitech-hidpp.c @@ -194,7 +194,6 @@ struct hidpp_device { struct work_struct work; struct kfifo delayed_work_fifo; - atomic_t connected; struct input_dev *delayed_input; unsigned long quirks; @@ -3893,8 +3892,6 @@ static int hidpp_raw_hidpp_event(struct hidpp_device *hidpp, u8 *data, } if (unlikely(hidpp_report_is_connect_event(hidpp, report))) { - atomic_set(&hidpp->connected, - !(report->rap.params[0] & (1 << 6))); if (schedule_work(&hidpp->work) == 0) dbg_hid("%s: connect event already queued\n", __func__); return 1; @@ -4189,12 +4186,14 @@ static struct input_dev *hidpp_allocate_input(struct hid_device *hdev) static void hidpp_connect_event(struct hidpp_device *hidpp) { struct hid_device *hdev = hidpp->hid_dev; - int ret = 0; - bool connected = atomic_read(&hidpp->connected); struct input_dev *input; char *name, *devm_name; + int ret; - if (!connected) { + /* Get device version to check if it is connected */ + ret = hidpp_root_get_protocol_version(hidpp); + if (ret) { + hid_info(hidpp->hid_dev, "Disconnected\n"); if (hidpp->battery.ps) { hidpp->battery.online = false; hidpp->battery.status = POWER_SUPPLY_STATUS_UNKNOWN; @@ -4236,16 +4235,6 @@ static void hidpp_connect_event(struct hidpp_device *hidpp) return; } - /* the device is already connected, we can ask for its name and - * protocol */ - if (!hidpp->protocol_major) { - ret = hidpp_root_get_protocol_version(hidpp); - if (ret) { - hid_err(hdev, "Can not get the protocol version.\n"); - return; - } - } - if (hidpp->protocol_major >= 2) { u8 feature_index; @@ -4395,7 +4384,6 @@ static int hidpp_probe(struct hid_device *hdev, const struct hid_device_id *id) { struct hidpp_device *hidpp; int ret; - bool connected; unsigned int connect_mask = HID_CONNECT_DEFAULT; /* report_fixup needs drvdata to be set before we call hid_parse */ @@ -4485,9 +4473,6 @@ static int hidpp_probe(struct hid_device *hdev, const struct hid_device_id *id) else hidpp_non_unifying_init(hidpp); - connected = hidpp_root_get_protocol_version(hidpp) == 0; - atomic_set(&hidpp->connected, connected); - schedule_work(&hidpp->work); flush_work(&hidpp->work);