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=-19.1 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, 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 6F111C47082 for ; Mon, 31 May 2021 14:14:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 54730613AD for ; Mon, 31 May 2021 14:14:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233695AbhEaOO5 (ORCPT ); Mon, 31 May 2021 10:14:57 -0400 Received: from mail.kernel.org ([198.145.29.99]:49808 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231984AbhEaNrU (ORCPT ); Mon, 31 May 2021 09:47:20 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id E429D61613; Mon, 31 May 2021 13:30:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1622467841; bh=ZriBpfqZx+VdzBDKFmZ5z/xlbGXCH2QH075GN56+CV0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jhdI/oiLGSncuNSlhkLX9fmUrXvQAGhOmKac8Ec3wl+6NloCqRoG72jTiIJPPSObw ssbLyGeqMJh7YEK6NFeS8ChSjDoRCQRBfpwbUFlL/TqpWSwTjn4h4CR+4boWKN+1vr lng/7qPbDVw2Ut7ggJqRu0K28i/WZP2ANMFh26pk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Colin Ian King , Davide Caratti , "David S. Miller" Subject: [PATCH 5.10 020/252] net/sched: fq_pie: re-factor fix for fq_pie endless loop Date: Mon, 31 May 2021 15:11:25 +0200 Message-Id: <20210531130658.667709190@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210531130657.971257589@linuxfoundation.org> References: <20210531130657.971257589@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: Davide Caratti commit 3a62fed2fd7b6fea96d720e779cafc30dfb3a22e upstream. the patch that fixed an endless loop in_fq_pie_init() was not considering that 65535 is a valid class id. The correct bugfix for this infinite loop is to change 'idx' to become an u32, like Colin proposed in the past [1]. Fix this as follows: - restore 65536 as maximum possible values of 'flows_cnt' - use u32 'idx' when iterating on 'q->flows' - fix the TDC selftest This reverts commit bb2f930d6dd708469a587dc9ed1efe1ef969c0bf. [1] https://lore.kernel.org/netdev/20210407163808.499027-1-colin.king@canonical.com/ CC: Colin Ian King CC: stable@vger.kernel.org Fixes: bb2f930d6dd7 ("net/sched: fix infinite loop in sch_fq_pie") Fixes: ec97ecf1ebe4 ("net: sched: add Flow Queue PIE packet scheduler") Signed-off-by: Davide Caratti Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/sched/sch_fq_pie.c | 10 +++++----- tools/testing/selftests/tc-testing/tc-tests/qdiscs/fq_pie.json | 8 ++++---- 2 files changed, 9 insertions(+), 9 deletions(-) --- a/net/sched/sch_fq_pie.c +++ b/net/sched/sch_fq_pie.c @@ -297,9 +297,9 @@ static int fq_pie_change(struct Qdisc *s goto flow_error; } q->flows_cnt = nla_get_u32(tb[TCA_FQ_PIE_FLOWS]); - if (!q->flows_cnt || q->flows_cnt >= 65536) { + if (!q->flows_cnt || q->flows_cnt > 65536) { NL_SET_ERR_MSG_MOD(extack, - "Number of flows must range in [1..65535]"); + "Number of flows must range in [1..65536]"); goto flow_error; } } @@ -367,7 +367,7 @@ static void fq_pie_timer(struct timer_li struct fq_pie_sched_data *q = from_timer(q, t, adapt_timer); struct Qdisc *sch = q->sch; spinlock_t *root_lock; /* to lock qdisc for probability calculations */ - u16 idx; + u32 idx; root_lock = qdisc_lock(qdisc_root_sleeping(sch)); spin_lock(root_lock); @@ -388,7 +388,7 @@ static int fq_pie_init(struct Qdisc *sch { struct fq_pie_sched_data *q = qdisc_priv(sch); int err; - u16 idx; + u32 idx; pie_params_init(&q->p_params); sch->limit = 10 * 1024; @@ -500,7 +500,7 @@ static int fq_pie_dump_stats(struct Qdis static void fq_pie_reset(struct Qdisc *sch) { struct fq_pie_sched_data *q = qdisc_priv(sch); - u16 idx; + u32 idx; INIT_LIST_HEAD(&q->new_flows); INIT_LIST_HEAD(&q->old_flows); --- a/tools/testing/selftests/tc-testing/tc-tests/qdiscs/fq_pie.json +++ b/tools/testing/selftests/tc-testing/tc-tests/qdiscs/fq_pie.json @@ -9,11 +9,11 @@ "setup": [ "$IP link add dev $DUMMY type dummy || /bin/true" ], - "cmdUnderTest": "$TC qdisc add dev $DUMMY root fq_pie flows 65536", - "expExitCode": "2", + "cmdUnderTest": "$TC qdisc add dev $DUMMY handle 1: root fq_pie flows 65536", + "expExitCode": "0", "verifyCmd": "$TC qdisc show dev $DUMMY", - "matchPattern": "qdisc", - "matchCount": "0", + "matchPattern": "qdisc fq_pie 1: root refcnt 2 limit 10240p flows 65536", + "matchCount": "1", "teardown": [ "$IP link del dev $DUMMY" ]