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=-5.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 91DFEC76186 for ; Sat, 27 Jul 2019 21:24:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 64C052147A for ; Sat, 27 Jul 2019 21:24:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1564262663; bh=qoE6ptOEb4ULRj1Rw05H1bmDm81qtxOhZ4CxCKq7DKs=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=1IuvLnMPLQ+fVm26ZLfCdd//qwHFuvxL4pi3kYUh53+ejfcv98spLbMSvRM15zC5m /rosposDszxooIyB0mIAMn/LinIap811FGGbwyyzdKOuSAhkYApWlfy8jPOb0bpyFI 1nzj6fHBgU1cwg2+jUYp89wHWD71cwHGRRMMnP/A= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727363AbfG0VYW (ORCPT ); Sat, 27 Jul 2019 17:24:22 -0400 Received: from mail.kernel.org ([198.145.29.99]:58438 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726404AbfG0VYW (ORCPT ); Sat, 27 Jul 2019 17:24:22 -0400 Received: from localhost (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (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 544B820657; Sat, 27 Jul 2019 21:24:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1564262661; bh=qoE6ptOEb4ULRj1Rw05H1bmDm81qtxOhZ4CxCKq7DKs=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=oXz/4F4yJJ1k+lSXFJfJQyElubb42wUxO4un+dZzd6/squ5M3/mqyv7ZuZ8kl6GWR yiYaOMJTny1lJ0+OI9E/z4nKemRQjgA3bJfxqybEhUkaVFefvauc0lzfVR8h3byeos hnRuZRewNOIIzW96DIxkqn2w66J2x6eZ9GDVJDFU= Date: Sat, 27 Jul 2019 17:24:20 -0400 From: Sasha Levin To: Greg Kroah-Hartman Cc: linux-kernel@vger.kernel.org, stable@vger.kernel.org, Eric Dumazet , Cong Wang , "David S. Miller" Subject: Re: [PATCH 5.2 14/66] net_sched: unset TCQ_F_CAN_BYPASS when adding filters Message-ID: <20190727212420.GA8637@sasha-vm> References: <20190726152301.936055394@linuxfoundation.org> <20190726152303.389623216@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: <20190726152303.389623216@linuxfoundation.org> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Fri, Jul 26, 2019 at 05:24:13PM +0200, Greg Kroah-Hartman wrote: >From: Cong Wang > >[ Upstream commit 3f05e6886a595c9a29a309c52f45326be917823c ] > >For qdisc's that support TC filters and set TCQ_F_CAN_BYPASS, >notably fq_codel, it makes no sense to let packets bypass the TC >filters we setup in any scenario, otherwise our packets steering >policy could not be enforced. > >This can be reproduced easily with the following script: > > ip li add dev dummy0 type dummy > ifconfig dummy0 up > tc qd add dev dummy0 root fq_codel > tc filter add dev dummy0 parent 8001: protocol arp basic action mirred egress redirect dev lo > tc filter add dev dummy0 parent 8001: protocol ip basic action mirred egress redirect dev lo > ping -I dummy0 192.168.112.1 > >Without this patch, packets are sent directly to dummy0 without >hitting any of the filters. With this patch, packets are redirected >to loopback as expected. > >This fix is not perfect, it only unsets the flag but does not set it back >because we have to save the information somewhere in the qdisc if we >really want that. Note, both fq_codel and sfq clear this flag in their >->bind_tcf() but this is clearly not sufficient when we don't use any >class ID. > >Fixes: 23624935e0c4 ("net_sched: TCQ_F_CAN_BYPASS generalization") >Cc: Eric Dumazet >Signed-off-by: Cong Wang >Reviewed-by: Eric Dumazet >Signed-off-by: David S. Miller >Signed-off-by: Greg Kroah-Hartman There's a fix for this one: 503d81d428bd5 ("net: sched: verify that q!=NULL before setting q->flags"). -- Thanks, Sasha