From mboxrd@z Thu Jan 1 00:00:00 1970 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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 CD4E9C43603 for ; Wed, 11 Dec 2019 15:25:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A2EB322B48 for ; Wed, 11 Dec 2019 15:25:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576077919; bh=B3UhKAqWVlq8iHx8Xvx/hiWVPkC7YtwfvTyR+6T9d2A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=F8ZwnL01SUi9NMD6rtKHWird8PMD6+oapZAhL5kZFLlwwKRNiYAB4IPz9jKcdhkB9 uyNcCDWL2DTkYIxXTrfN+PxblXEGIKKbwlVgPR/4eL/e52no3BB+0w9Xq2ojqaIj1Z xUT/Bwl7iGvkrOz8+yG2wjXOVc4U9bRlM8bq80iw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732803AbfLKPZS (ORCPT ); Wed, 11 Dec 2019 10:25:18 -0500 Received: from mail.kernel.org ([198.145.29.99]:57106 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732659AbfLKPZQ (ORCPT ); Wed, 11 Dec 2019 10:25:16 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 538FF22B48; Wed, 11 Dec 2019 15:25:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576077915; bh=B3UhKAqWVlq8iHx8Xvx/hiWVPkC7YtwfvTyR+6T9d2A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TkEEUt8cgP4cFmhXh4rw8XyMg1BVh8lNRoOWsK8trqVNsP2w8aJliCYWh8x/gFvVo y7DzflsFU/W8Dxc004qx7xImhAQtChDbyHZpLr1PRfupFAxHq/r3Cb3q8gxFUOMB2Z iRNyPTspqo0VTBuf80lqZY15t4KBWFyr3ZbK0yHg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+19340dff067c2d3835c0@syzkaller.appspotmail.com, Dmitry Torokhov Subject: [PATCH 4.19 218/243] tty: vt: keyboard: reject invalid keycodes Date: Wed, 11 Dec 2019 16:06:20 +0100 Message-Id: <20191211150354.051637725@linuxfoundation.org> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20191211150339.185439726@linuxfoundation.org> References: <20191211150339.185439726@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Dmitry Torokhov commit b2b2dd71e0859436d4e05b2f61f86140250ed3f8 upstream. Do not try to handle keycodes that are too big, otherwise we risk doing out-of-bounds writes: BUG: KASAN: global-out-of-bounds in clear_bit include/asm-generic/bitops-instrumented.h:56 [inline] BUG: KASAN: global-out-of-bounds in kbd_keycode drivers/tty/vt/keyboard.c:1411 [inline] BUG: KASAN: global-out-of-bounds in kbd_event+0xe6b/0x3790 drivers/tty/vt/keyboard.c:1495 Write of size 8 at addr ffffffff89a1b2d8 by task syz-executor108/1722 ... kbd_keycode drivers/tty/vt/keyboard.c:1411 [inline] kbd_event+0xe6b/0x3790 drivers/tty/vt/keyboard.c:1495 input_to_handler+0x3b6/0x4c0 drivers/input/input.c:118 input_pass_values.part.0+0x2e3/0x720 drivers/input/input.c:145 input_pass_values drivers/input/input.c:949 [inline] input_set_keycode+0x290/0x320 drivers/input/input.c:954 evdev_handle_set_keycode_v2+0xc4/0x120 drivers/input/evdev.c:882 evdev_do_ioctl drivers/input/evdev.c:1150 [inline] In this case we were dealing with a fuzzed HID device that declared over 12K buttons, and while HID layer should not be reporting to us such big keycodes, we should also be defensive and reject invalid data ourselves as well. Reported-by: syzbot+19340dff067c2d3835c0@syzkaller.appspotmail.com Signed-off-by: Dmitry Torokhov Cc: stable Link: https://lore.kernel.org/r/20191122204220.GA129459@dtor-ws Signed-off-by: Greg Kroah-Hartman --- drivers/tty/vt/keyboard.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/tty/vt/keyboard.c +++ b/drivers/tty/vt/keyboard.c @@ -1491,7 +1491,7 @@ static void kbd_event(struct input_handl if (event_type == EV_MSC && event_code == MSC_RAW && HW_RAW(handle->dev)) kbd_rawcode(value); - if (event_type == EV_KEY) + if (event_type == EV_KEY && event_code <= KEY_MAX) kbd_keycode(event_code, value, HW_RAW(handle->dev)); spin_unlock(&kbd_event_lock);