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=-20.2 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=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 D6E82C433EF for ; Mon, 20 Sep 2021 17:40:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BFFBB6137A for ; Mon, 20 Sep 2021 17:40:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1352714AbhITRl3 (ORCPT ); Mon, 20 Sep 2021 13:41:29 -0400 Received: from mail.kernel.org ([198.145.29.99]:44120 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1349373AbhITRjH (ORCPT ); Mon, 20 Sep 2021 13:39:07 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 6499361B46; Mon, 20 Sep 2021 17:07:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1632157652; bh=nagUNhdVX+TGIxHlhOJnRD2CoM61qtbYaveI4oAPrpE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SK2dIAQhbG6Qj0AP0dyXcQK0HH/Sfqs9MdaXUVg3nDolaNlHy2oi2u3g/el5x5n5g ie7WZXc12MXLPjIDZxwcDZxqjOePU9jTP8Rc3RO1JwBpdWRBdT3IoRciZ9DgeiUkfD ywD5r6x6cyIjCsTbjFWgMOB3XvTPFfmPtq06zVrY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Pavel Skripkin , Marcel Holtmann , Sasha Levin , syzbot+be2baed593ea56c6a84c@syzkaller.appspotmail.com Subject: [PATCH 4.19 089/293] Bluetooth: add timeout sanity check to hci_inquiry Date: Mon, 20 Sep 2021 18:40:51 +0200 Message-Id: <20210920163936.315828623@linuxfoundation.org> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20210920163933.258815435@linuxfoundation.org> References: <20210920163933.258815435@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Pavel Skripkin [ Upstream commit f41a4b2b5eb7872109723dab8ae1603bdd9d9ec1 ] Syzbot hit "task hung" bug in hci_req_sync(). The problem was in unreasonable huge inquiry timeout passed from userspace. Fix it by adding sanity check for timeout value to hci_inquiry(). Since hci_inquiry() is the only user of hci_req_sync() with user controlled timeout value, it makes sense to check timeout value in hci_inquiry() and don't touch hci_req_sync(). Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-and-tested-by: syzbot+be2baed593ea56c6a84c@syzkaller.appspotmail.com Signed-off-by: Pavel Skripkin Signed-off-by: Marcel Holtmann Signed-off-by: Sasha Levin --- net/bluetooth/hci_core.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c index ec6150564f59..26acacb2fa95 100644 --- a/net/bluetooth/hci_core.c +++ b/net/bluetooth/hci_core.c @@ -1296,6 +1296,12 @@ int hci_inquiry(void __user *arg) goto done; } + /* Restrict maximum inquiry length to 60 seconds */ + if (ir.length > 60) { + err = -EINVAL; + goto done; + } + hci_dev_lock(hdev); if (inquiry_cache_age(hdev) > INQUIRY_CACHE_AGE_MAX || inquiry_cache_empty(hdev) || ir.flags & IREQ_CACHE_FLUSH) { -- 2.30.2