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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 15573C4332F for ; Tue, 8 Nov 2022 13:49:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234595AbiKHNth (ORCPT ); Tue, 8 Nov 2022 08:49:37 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49462 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234611AbiKHNtg (ORCPT ); Tue, 8 Nov 2022 08:49:36 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 946096348 for ; Tue, 8 Nov 2022 05:49:35 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 319036130A for ; Tue, 8 Nov 2022 13:49:35 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3E240C433D6; Tue, 8 Nov 2022 13:49:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1667915374; bh=xeTYHi29KjNpP8E4YTtf+JoAa5CgYsebN+CEf34EA6g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fnL4HSqqYH03aXo5kk0QDLEX0lxeiLdqphH3q1+Rf+bS4d9gX9eov4ytZPJK/JYFC rOyis2uGzDDZrXw9NrozV7h3xXRlbdUMA+3O+9BNaEFOjXjeHlTe0lJoDBwCyg8XcF hI7tx/yiCKYAExC9n1MBu1K4RoFtlFq/XDsAz8k8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Dan Carpenter , Eric Dumazet , "David S. Miller" , Sasha Levin Subject: [PATCH 5.4 13/74] net: sched: Fix use after free in red_enqueue() Date: Tue, 8 Nov 2022 14:38:41 +0100 Message-Id: <20221108133334.218948364@linuxfoundation.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221108133333.659601604@linuxfoundation.org> References: <20221108133333.659601604@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Dan Carpenter [ Upstream commit 8bdc2acd420c6f3dd1f1c78750ec989f02a1e2b9 ] We can't use "skb" again after passing it to qdisc_enqueue(). This is basically identical to commit 2f09707d0c97 ("sch_sfb: Also store skb len before calling child enqueue"). Fixes: d7f4f332f082 ("sch_red: update backlog as well") Signed-off-by: Dan Carpenter Reviewed-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- net/sched/sch_red.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/net/sched/sch_red.c b/net/sched/sch_red.c index 7741f102be4a..476853ff6989 100644 --- a/net/sched/sch_red.c +++ b/net/sched/sch_red.c @@ -59,6 +59,7 @@ static int red_enqueue(struct sk_buff *skb, struct Qdisc *sch, { struct red_sched_data *q = qdisc_priv(sch); struct Qdisc *child = q->qdisc; + unsigned int len; int ret; q->vars.qavg = red_calc_qavg(&q->parms, @@ -94,9 +95,10 @@ static int red_enqueue(struct sk_buff *skb, struct Qdisc *sch, break; } + len = qdisc_pkt_len(skb); ret = qdisc_enqueue(skb, child, to_free); if (likely(ret == NET_XMIT_SUCCESS)) { - qdisc_qstats_backlog_inc(sch, skb); + sch->qstats.backlog += len; sch->q.qlen++; } else if (net_xmit_drop_count(ret)) { q->stats.pdrop++; -- 2.35.1