From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 79FC615CAE for ; Tue, 8 Nov 2022 14:09:10 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E31CDC433C1; Tue, 8 Nov 2022 14:09:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1667916550; bh=MV3LsN1YBAo3F0nQ11qgRDKoUTwrZ1JCo+rs848gggE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=KOPFAJRDH6VUkNTE8pUMGNf58XrAfaJ+7vlbCnH7lFy+Z1YK8y2MGFIDdKjD6wGYr ijAzNgZyIZUb1g2XIvpXmX3OThynVhFYcfw6FpxWBipGk0NSk7Be6F3h/BfS4jbF+i VhOavkkXnOKM4rLQYBnayRI6R2rSHXzJ0LR/OU+w= 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 6.0 028/197] net: sched: Fix use after free in red_enqueue() Date: Tue, 8 Nov 2022 14:37:46 +0100 Message-Id: <20221108133356.074582327@linuxfoundation.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221108133354.787209461@linuxfoundation.org> References: <20221108133354.787209461@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 f1e013e3f04a..935d90874b1b 100644 --- a/net/sched/sch_red.c +++ b/net/sched/sch_red.c @@ -72,6 +72,7 @@ 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, @@ -126,9 +127,10 @@ 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