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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 30D30C54FD0 for ; Thu, 23 Apr 2020 23:10:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 191D120780 for ; Thu, 23 Apr 2020 23:10:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728609AbgDWXKf (ORCPT ); Thu, 23 Apr 2020 19:10:35 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:50388 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728600AbgDWXGx (ORCPT ); Thu, 23 Apr 2020 19:06:53 -0400 Received: from [192.168.4.242] (helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1jRkvf-0004sZ-9R; Fri, 24 Apr 2020 00:06:47 +0100 Received: from ben by deadeye with local (Exim 4.93) (envelope-from ) id 1jRkvb-00E70v-1M; Fri, 24 Apr 2020 00:06:43 +0100 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, Denis Kirjanov , syzbot+c769968809f9359b07aa@syzkaller.appspotmail.com, syzbot+76f3a30e88d256644c78@syzkaller.appspotmail.com, "Dmitry Torokhov" Date: Fri, 24 Apr 2020 00:07:21 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) X-Patchwork-Hint: ignore Subject: [PATCH 3.16 214/245] Input: add safety guards to input_set_keycode() In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.242 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.83-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Dmitry Torokhov commit cb222aed03d798fc074be55e59d9a112338ee784 upstream. If we happen to have a garbage in input device's keycode table with values too big we'll end up doing clear_bit() with offset way outside of our bitmaps, damaging other objects within an input device or even outside of it. Let's add sanity checks to the returned old keycodes. Reported-by: syzbot+c769968809f9359b07aa@syzkaller.appspotmail.com Reported-by: syzbot+76f3a30e88d256644c78@syzkaller.appspotmail.com Link: https://lore.kernel.org/r/20191207212757.GA245964@dtor-ws Signed-off-by: Dmitry Torokhov Signed-off-by: Ben Hutchings --- drivers/input/input.c | 26 ++++++++++++++++---------- 1 file changed, 16 insertions(+), 10 deletions(-) --- a/drivers/input/input.c +++ b/drivers/input/input.c @@ -841,16 +841,18 @@ static int input_default_setkeycode(stru } } - __clear_bit(*old_keycode, dev->keybit); - __set_bit(ke->keycode, dev->keybit); - - for (i = 0; i < dev->keycodemax; i++) { - if (input_fetch_keycode(dev, i) == *old_keycode) { - __set_bit(*old_keycode, dev->keybit); - break; /* Setting the bit twice is useless, so break */ + if (*old_keycode <= KEY_MAX) { + __clear_bit(*old_keycode, dev->keybit); + for (i = 0; i < dev->keycodemax; i++) { + if (input_fetch_keycode(dev, i) == *old_keycode) { + __set_bit(*old_keycode, dev->keybit); + /* Setting the bit twice is useless, so break */ + break; + } } } + __set_bit(ke->keycode, dev->keybit); return 0; } @@ -906,9 +908,13 @@ int input_set_keycode(struct input_dev * * Simulate keyup event if keycode is not present * in the keymap anymore */ - if (test_bit(EV_KEY, dev->evbit) && - !is_event_supported(old_keycode, dev->keybit, KEY_MAX) && - __test_and_clear_bit(old_keycode, dev->key)) { + if (old_keycode > KEY_MAX) { + dev_warn(dev->dev.parent ?: &dev->dev, + "%s: got too big old keycode %#x\n", + __func__, old_keycode); + } else if (test_bit(EV_KEY, dev->evbit) && + !is_event_supported(old_keycode, dev->keybit, KEY_MAX) && + __test_and_clear_bit(old_keycode, dev->key)) { struct input_value vals[] = { { EV_KEY, old_keycode, 0 }, input_value_sync