From patchwork Sat May 22 13:14:45 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Davide Caratti X-Patchwork-Id: 12274517 X-Patchwork-Delegate: kuba@kernel.org 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=-16.1 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 autolearn=ham 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 5E081C2B9F2 for ; Sat, 22 May 2021 13:15:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 35C4261205 for ; Sat, 22 May 2021 13:15:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231152AbhEVNQY (ORCPT ); Sat, 22 May 2021 09:16:24 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:48077 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230466AbhEVNQY (ORCPT ); Sat, 22 May 2021 09:16:24 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1621689299; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=iFg8QwTUxh0ja5IOJu6njrdfhu3mkA1LjZC4P7XEI8E=; b=cmUIxWwvS5Uup2NhLWWSAZbhXA5eDpy/EMdoToZvRzFNT+fZVuA1RhRUzZkx8SR2img7EZ Tb61xoMg1SLq+2W9613QkZs1iCes2Xq9kLq4h9RK4pWSxxACFePl/+2rm1TcyPT5Ypu0Hu FyBfdE38JsoqKxPjJkUPlUIYZiqG8zc= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-482-0PR9d2X0O8-kQ5EDivruDg-1; Sat, 22 May 2021 09:14:57 -0400 X-MC-Unique: 0PR9d2X0O8-kQ5EDivruDg-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id F24AD180FD62; Sat, 22 May 2021 13:14:55 +0000 (UTC) Received: from dcaratti.station (unknown [10.40.194.65]) by smtp.corp.redhat.com (Postfix) with ESMTP id 832AB2C6FD; Sat, 22 May 2021 13:14:51 +0000 (UTC) From: Davide Caratti To: Jamal Hadi Salim , Cong Wang , Jiri Pirko , "David S. Miller" , Jakub Kicinski , "V. Saicharan" , "Sachin D. Patil" , "Mohit P. Tahiliani" , Mohit Bhasi , Leslie Monis , Ivan Vecera , Colin Ian King Cc: netdev@vger.kernel.org Subject: [PATCH net 1/2] net/sched: fq_pie: re-factor fix for fq_pie endless loop Date: Sat, 22 May 2021 15:14:45 +0200 Message-Id: In-Reply-To: References: MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org 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 --- net/sched/sch_fq_pie.c | 10 +++++----- .../selftests/tc-testing/tc-tests/qdiscs/fq_pie.json | 8 ++++---- 2 files changed, 9 insertions(+), 9 deletions(-) diff --git a/net/sched/sch_fq_pie.c b/net/sched/sch_fq_pie.c index 949163fe68af..266c7c1869d9 100644 --- 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 *sch, struct nlattr *opt, 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_list *t) 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 nlattr *opt, { 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 Qdisc *sch, struct gnet_dump *d) 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); diff --git a/tools/testing/selftests/tc-testing/tc-tests/qdiscs/fq_pie.json b/tools/testing/selftests/tc-testing/tc-tests/qdiscs/fq_pie.json index 1cda2e11b3ad..773c5027553d 100644 --- 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" ]