From patchwork Thu Feb 3 14:32:16 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Benjamin Tissoires X-Patchwork-Id: 540209 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 B5E25C433FE for ; Thu, 3 Feb 2022 14:32:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1351190AbiBCOcw (ORCPT ); Thu, 3 Feb 2022 09:32:52 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:49187 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1351206AbiBCOcw (ORCPT ); Thu, 3 Feb 2022 09:32:52 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1643898771; 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=VoRCLd9eiRJJa6lwo70UloqImIyHvXdJD57CHhtcnqY=; b=Q2Pk5V0D4FxTuH6MV629a3SzdNCI2jePQ9vgYrcKfZhKNKPMFs2TNyhyPqOwAfh8I7UukH aJvSj0C7gaU1Fo5c//G06S1OZa8XvqfsHBdLSVvyRoM/j4MTAbh0x5tWy7i/m1q3PBSdwW v7jI+Ah2c+EYZICgQIvhkV0LIsOkLhQ= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-573-PNN1-BKzPdSpfRmtqeYMZA-1; Thu, 03 Feb 2022 09:32:46 -0500 X-MC-Unique: PNN1-BKzPdSpfRmtqeYMZA-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id A9AEB343CC; Thu, 3 Feb 2022 14:32:44 +0000 (UTC) Received: from plouf.redhat.com (unknown [10.39.192.114]) by smtp.corp.redhat.com (Postfix) with ESMTP id 464DB7D4D0; Thu, 3 Feb 2022 14:32:42 +0000 (UTC) From: Benjamin Tissoires To: Jiri Kosina , Dmitry Torokhov , Jonathan Corbet , =?utf-8?q?Ahelenia_Ziemia=C5=84ska?= , Ping Cheng , Aaron Armstrong Skomra , Jason Gerecke , Peter Hutterer Cc: linux-input@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, Benjamin Tissoires Subject: [PATCH v2 02/12] HID: core: de-duplicate some code in hid_input_field() Date: Thu, 3 Feb 2022 15:32:16 +0100 Message-Id: <20220203143226.4023622-3-benjamin.tissoires@redhat.com> In-Reply-To: <20220203143226.4023622-1-benjamin.tissoires@redhat.com> References: <20220203143226.4023622-1-benjamin.tissoires@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Precedence: bulk List-ID: X-Mailing-List: linux-input@vger.kernel.org I had to go twice through the history to get a grasp at this code. De-duplicate the various tests in one common helper to make it more explicit. Note that the `HID_UP_KEYBOARD + 1` condition is tested through https://gitlab.freedesktop.org/libevdev/hid-tools/-/merge_requests/121 Signed-off-by: Benjamin Tissoires --- drivers/hid/hid-core.c | 54 ++++++++++++++++++++++++++++++------------ 1 file changed, 39 insertions(+), 15 deletions(-) diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c index 75e7b8447bf7..fad4dbdf6391 100644 --- a/drivers/hid/hid-core.c +++ b/drivers/hid/hid-core.c @@ -1525,6 +1525,24 @@ static void hid_process_event(struct hid_device *hid, struct hid_field *field, hid->hiddev_hid_event(hid, field, usage, value); } +/* + * Checks if the given value is valid within this field + */ +static inline int hid_array_value_is_valid(struct hid_field *field, + __s32 value) +{ + __s32 min = field->logical_minimum; + + /* + * Value needs to be between logical min and max, and + * (value - min) is used as an index in the usage array. + * This array is of size field->maxusage + */ + return value >= min && + value <= field->logical_maximum && + value - min < field->maxusage; +} + /* * Analyse a received field, and fetch the data from it. The field * content is stored for next report processing (we do differential @@ -1539,7 +1557,6 @@ static void hid_input_field(struct hid_device *hid, struct hid_field *field, unsigned offset = field->report_offset; unsigned size = field->report_size; __s32 min = field->logical_minimum; - __s32 max = field->logical_maximum; __s32 *value; value = field->new_value; @@ -1554,8 +1571,7 @@ static void hid_input_field(struct hid_device *hid, struct hid_field *field, /* Ignore report if ErrorRollOver */ if (!(field->flags & HID_MAIN_ITEM_VARIABLE) && - value[n] >= min && value[n] <= max && - value[n] - min < field->maxusage && + hid_array_value_is_valid(field, value[n]) && field->usage[value[n] - min].hid == HID_UP_KEYBOARD + 1) return; } @@ -1563,21 +1579,29 @@ static void hid_input_field(struct hid_device *hid, struct hid_field *field, for (n = 0; n < count; n++) { if (HID_MAIN_ITEM_VARIABLE & field->flags) { - hid_process_event(hid, field, &field->usage[n], value[n], interrupt); + hid_process_event(hid, + field, + &field->usage[n], + value[n], + interrupt); continue; } - if (field->value[n] >= min && field->value[n] <= max - && field->value[n] - min < field->maxusage - && field->usage[field->value[n] - min].hid - && search(value, field->value[n], count)) - hid_process_event(hid, field, &field->usage[field->value[n] - min], 0, interrupt); - - if (value[n] >= min && value[n] <= max - && value[n] - min < field->maxusage - && field->usage[value[n] - min].hid - && search(field->value, value[n], count)) - hid_process_event(hid, field, &field->usage[value[n] - min], 1, interrupt); + if (hid_array_value_is_valid(field, field->value[n]) && + search(value, field->value[n], count)) + hid_process_event(hid, + field, + &field->usage[field->value[n] - min], + 0, + interrupt); + + if (hid_array_value_is_valid(field, value[n]) && + search(field->value, value[n], count)) + hid_process_event(hid, + field, + &field->usage[value[n] - min], + 1, + interrupt); } memcpy(field->value, value, count * sizeof(__s32));