From patchwork Sun Apr 4 08:04:26 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Hans de Goede X-Patchwork-Id: 12182197 X-Patchwork-Delegate: jikos@jikos.cz 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=-15.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 9F2C5C43460 for ; Sun, 4 Apr 2021 08:04:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 60FDD61368 for ; Sun, 4 Apr 2021 08:04:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230161AbhDDIEv (ORCPT ); Sun, 4 Apr 2021 04:04:51 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:22895 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230089AbhDDIEv (ORCPT ); Sun, 4 Apr 2021 04:04:51 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1617523487; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=57aYw8CIHLVgvnmjlleQRGI7SQnl+sHSZtu0KcoI/Qg=; b=Ft48I4x0PPu9Js9dT5MyBonH/6AtwB6dVsvqUjiF+YDciRBFG8RvGM7j2ysMl7QzAUXL3g ZBYT3lDOJ74PtfSHVofyhVxN+2oZKlYCo5+9PgSdWToRBrB0A+CAD9T6i+rts+a9GgyhQ8 aZ/l5mUjYi0gKYpkofY076C5rOj9UPQ= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-453-6VztriD_Nxm4SPitetmhCw-1; Sun, 04 Apr 2021 04:04:45 -0400 X-MC-Unique: 6VztriD_Nxm4SPitetmhCw-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 0EA7087A826; Sun, 4 Apr 2021 08:04:44 +0000 (UTC) Received: from x1.localdomain (ovpn-112-48.ams2.redhat.com [10.36.112.48]) by smtp.corp.redhat.com (Postfix) with ESMTP id 7C592100E113; Sun, 4 Apr 2021 08:04:42 +0000 (UTC) From: Hans de Goede To: Jiri Kosina , Benjamin Tissoires , Alexander Kobel Cc: Hans de Goede , Pavel Machek , =?utf-8?q?Marek_Beh=C3=BAn?= , linux-input@vger.kernel.org, linux-leds@vger.kernel.org Subject: [PATCH v2 resend 3/9] HID: lenovo: Check hid_get_drvdata() returns non NULL in lenovo_event() Date: Sun, 4 Apr 2021 10:04:26 +0200 Message-Id: <20210404080432.4322-4-hdegoede@redhat.com> In-Reply-To: <20210404080432.4322-1-hdegoede@redhat.com> References: <20210404080432.4322-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Precedence: bulk List-ID: X-Mailing-List: linux-input@vger.kernel.org The HID lenovo probe function only attaches drvdata to one of the USB interfaces, but lenovo_event() will get called for all USB interfaces to which hid-lenovo is bound. This allows a malicious device to fake being a device handled by hid-lenovo, which generates events for which lenovo_event() has special handling (and thus dereferences hid_get_drvdata()) on another interface triggering a NULL pointer exception. Add a check for hid_get_drvdata() returning NULL, avoiding this possible NULL pointer exception. Fixes: bc04b37ea0ec ("HID: lenovo: Add ThinkPad 10 Ultrabook Keyboard support") Reviewed-by: Marek Behún Signed-off-by: Hans de Goede --- drivers/hid/hid-lenovo.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/hid/hid-lenovo.c b/drivers/hid/hid-lenovo.c index ee175ab54281..b2596ed37880 100644 --- a/drivers/hid/hid-lenovo.c +++ b/drivers/hid/hid-lenovo.c @@ -508,6 +508,9 @@ static int lenovo_event_cptkbd(struct hid_device *hdev, static int lenovo_event(struct hid_device *hdev, struct hid_field *field, struct hid_usage *usage, __s32 value) { + if (!hid_get_drvdata(hdev)) + return 0; + switch (hdev->product) { case USB_DEVICE_ID_LENOVO_CUSBKBD: case USB_DEVICE_ID_LENOVO_CBTKBD: