From patchwork Mon May 18 17:35:36 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 225887 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,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 8BD45C433E0 for ; Mon, 18 May 2020 17:38:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6BBD52083E for ; Mon, 18 May 2020 17:38:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1589823518; bh=NElWdHSPE0Co3MWskyrX7Zbj7D9KTvqkOaLCXT/v8lg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Jj584QkC8BVamGRrUrkdH3SM4ysF2LnI5w/VI31iMe6t/yG2uZoj1qZnmSTzNds/j CKu8TPUrRJ0ekR00ey5BVQa+RANec2tIgni7+jXEySP6uruYBVILxYm0BHK0vrlVio D9vwR6jvHfyV5xrbVLe+RWwYbR5EypeJiBO6lfyM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728535AbgERRif (ORCPT ); Mon, 18 May 2020 13:38:35 -0400 Received: from mail.kernel.org ([198.145.29.99]:60934 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727938AbgERRie (ORCPT ); Mon, 18 May 2020 13:38:34 -0400 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 6D441207C4; Mon, 18 May 2020 17:38:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1589823513; bh=NElWdHSPE0Co3MWskyrX7Zbj7D9KTvqkOaLCXT/v8lg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jw7H9T4IHNMhYzxrYYWeh6PtIFngPF32/lpVbVACmND0dvK+DWDQoVsdbRMRQkjMO YDDWmTyDeCPa6I06jQhHEJQD2nu1MqN1g0as76aiB9dJCyUDDcAirOZZlTpePKn89J irvRlh5I7KI/uAIHcNErx9U7ExsS18Jdqh2rNLgw= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Dumazet , syzbot+0251e883fe39e7a0cb0a@syzkaller.appspotmail.com, "Jason A. Donenfeld" , "David S. Miller" Subject: [PATCH 4.4 05/86] sch_sfq: validate silly quantum values Date: Mon, 18 May 2020 19:35:36 +0200 Message-Id: <20200518173451.334899502@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200518173450.254571947@linuxfoundation.org> References: <20200518173450.254571947@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Eric Dumazet [ Upstream commit df4953e4e997e273501339f607b77953772e3559 ] syzbot managed to set up sfq so that q->scaled_quantum was zero, triggering an infinite loop in sfq_dequeue() More generally, we must only accept quantum between 1 and 2^18 - 7, meaning scaled_quantum must be in [1, 0x7FFF] range. Otherwise, we also could have a loop in sfq_dequeue() if scaled_quantum happens to be 0x8000, since slot->allot could indefinitely switch between 0 and 0x8000. Fixes: eeaeb068f139 ("sch_sfq: allow big packets and be fair") Signed-off-by: Eric Dumazet Reported-by: syzbot+0251e883fe39e7a0cb0a@syzkaller.appspotmail.com Cc: Jason A. Donenfeld Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/sched/sch_sfq.c | 9 +++++++++ 1 file changed, 9 insertions(+) --- a/net/sched/sch_sfq.c +++ b/net/sched/sch_sfq.c @@ -635,6 +635,15 @@ static int sfq_change(struct Qdisc *sch, if (ctl->divisor && (!is_power_of_2(ctl->divisor) || ctl->divisor > 65536)) return -EINVAL; + + /* slot->allot is a short, make sure quantum is not too big. */ + if (ctl->quantum) { + unsigned int scaled = SFQ_ALLOT_SIZE(ctl->quantum); + + if (scaled <= 0 || scaled > SHRT_MAX) + return -EINVAL; + } + if (ctl_v1 && !red_check_params(ctl_v1->qth_min, ctl_v1->qth_max, ctl_v1->Wlog)) return -EINVAL;