From patchwork Wed Nov 23 06:30:57 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yue Haibing X-Patchwork-Id: 13053130 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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CD8A8C433FE for ; Wed, 23 Nov 2022 06:31:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235804AbiKWGbL (ORCPT ); Wed, 23 Nov 2022 01:31:11 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36544 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234531AbiKWGbK (ORCPT ); Wed, 23 Nov 2022 01:31:10 -0500 Received: from szxga08-in.huawei.com (szxga08-in.huawei.com [45.249.212.255]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CC2B15C74E; Tue, 22 Nov 2022 22:31:09 -0800 (PST) Received: from canpemm500007.china.huawei.com (unknown [172.30.72.53]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4NHB8F43Wpz15Mlp; Wed, 23 Nov 2022 14:30:37 +0800 (CST) Received: from localhost (10.174.179.215) by canpemm500007.china.huawei.com (7.192.104.62) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Wed, 23 Nov 2022 14:31:07 +0800 From: YueHaibing To: , , , , CC: , , YueHaibing Subject: [PATCH net] net: hsr: Fix potential use-after-free Date: Wed, 23 Nov 2022 14:30:57 +0800 Message-ID: <20221123063057.25952-1-yuehaibing@huawei.com> X-Mailer: git-send-email 2.10.2.windows.1 MIME-Version: 1.0 X-Originating-IP: [10.174.179.215] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To canpemm500007.china.huawei.com (7.192.104.62) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org The skb is delivered to netif_rx() which may free it, after calling this, dereferencing skb may trigger use-after-free. Fixes: f266a683a480 ("net/hsr: Better frame dispatch") Signed-off-by: YueHaibing --- net/hsr/hsr_forward.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/net/hsr/hsr_forward.c b/net/hsr/hsr_forward.c index a50429a62f74..56bb27d67a2e 100644 --- a/net/hsr/hsr_forward.c +++ b/net/hsr/hsr_forward.c @@ -351,17 +351,18 @@ static void hsr_deliver_master(struct sk_buff *skb, struct net_device *dev, struct hsr_node *node_src) { bool was_multicast_frame; - int res; + int res, recv_len; was_multicast_frame = (skb->pkt_type == PACKET_MULTICAST); hsr_addr_subst_source(node_src, skb); skb_pull(skb, ETH_HLEN); + recv_len = skb->len; res = netif_rx(skb); if (res == NET_RX_DROP) { dev->stats.rx_dropped++; } else { dev->stats.rx_packets++; - dev->stats.rx_bytes += skb->len; + dev->stats.rx_bytes += recv_len; if (was_multicast_frame) dev->stats.multicast++; }