From patchwork Wed May 12 14:49:06 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: "gregkh@linuxfoundation.org" X-Patchwork-Id: 437885 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=-19.4 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, 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 ECCACC43617 for ; Wed, 12 May 2021 16:57:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BB25B611BE for ; Wed, 12 May 2021 16:57:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236798AbhELQ5l (ORCPT ); Wed, 12 May 2021 12:57:41 -0400 Received: from mail.kernel.org ([198.145.29.99]:35800 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244084AbhELQmd (ORCPT ); Wed, 12 May 2021 12:42:33 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id A7AA861D15; Wed, 12 May 2021 16:10:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1620835825; bh=QYHYkripwHaGR1tW7wMyF4+coN5sPnCg/WOWkblfgL4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=IbraDKjDVmqvTImFe6MM7cUyyaS9rExz6DkpF2AFdvdlNypAiGGEBPxlUHDeAN/JG XHz1mdwXSOcBYgT28ZPW+uyT6RqjDKTEstWbKX0lzivg3LE1s506z1ZQzS3tWZI5Cu HAf7nKwAAlOvBAN8d28C4EcYEs0MZAqmXCQkspYM= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, =?utf-8?q?Marek_Beh=C3=BAn?= , Hans de Goede , Jiri Kosina , Sasha Levin Subject: [PATCH 5.12 500/677] HID: lenovo: Check hid_get_drvdata() returns non NULL in lenovo_event() Date: Wed, 12 May 2021 16:49:06 +0200 Message-Id: <20210512144853.988770686@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210512144837.204217980@linuxfoundation.org> References: <20210512144837.204217980@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Hans de Goede [ Upstream commit 34348a8661e3cd67dcf6938f08c8bb77522301f7 ] 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 Signed-off-by: Jiri Kosina Signed-off-by: Sasha Levin --- 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: