From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6D22E11CAA for ; Fri, 15 Sep 2023 20:45:19 +0000 (UTC) Received: from out-228.mta1.migadu.com (out-228.mta1.migadu.com [95.215.58.228]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 282D9186 for ; Fri, 15 Sep 2023 13:45:18 -0700 (PDT) Message-ID: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1694810716; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=zZu5o0cgVYXAFH7d9696U+gHAz/I7CL0OXnkm5dCDf8=; b=ArCTnuBFrZVZMvsfRzsFhqroZehMZUBRALdUc4bMzmQq2Q7492lBhGukC9uInB4RKhrBz2 7ehHSbx2VaI3j8kX6772ZWNTwZtohLKarNF9PJFco5jmi3IkQtEVRK2Yu9CPOrOuyV6aBI qFnY9fBRoFi2xRIgc83tvyG7JBzFIk4= Date: Fri, 15 Sep 2023 21:45:13 +0100 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Subject: Re: [PATCH] net: sched: qfq: dont intepret cls results when asked to drop Content-Language: en-US To: Ma Ke , jhs@mojatatu.com, xiyou.wangcong@gmail.com, jiri@resnulli.us, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org References: <20230915142355.3411527-1-make_ruc2021@163.com> X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Vadim Fedorenko In-Reply-To: <20230915142355.3411527-1-make_ruc2021@163.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Migadu-Flow: FLOW_OUT X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_BLOCKED, SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net On 15/09/2023 15:23, Ma Ke wrote: > If asked to drop a packet via TC_ACT_SHOT it is unsafe to > assume that res.class contains a valid pointer. > > Signed-off-by: Ma Ke > --- > net/sched/sch_qfq.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/net/sched/sch_qfq.c b/net/sched/sch_qfq.c > index 546c10adcacd..91c323eff012 100644 > --- a/net/sched/sch_qfq.c > +++ b/net/sched/sch_qfq.c > @@ -696,6 +696,8 @@ static struct qfq_class *qfq_classify(struct sk_buff *skb, struct Qdisc *sch, > fl = rcu_dereference_bh(q->filter_list); > result = tcf_classify(skb, NULL, fl, &res, false); > if (result >= 0) { > + if (result == TC_ACT_SHOT) > + return NULL; The same comment again - the check is meaningless. > #ifdef CONFIG_NET_CLS_ACT > switch (result) { > case TC_ACT_QUEUED: > @@ -703,8 +705,6 @@ static struct qfq_class *qfq_classify(struct sk_buff *skb, struct Qdisc *sch, > case TC_ACT_TRAP: > *qerr = NET_XMIT_SUCCESS | __NET_XMIT_STOLEN; > fallthrough; > - case TC_ACT_SHOT: > - return NULL; > } > #endif > cl = (struct qfq_class *)res.class;