From patchwork Wed Jul 27 09:33:12 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: shaozhengchao X-Patchwork-Id: 12930261 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 E88EFC19F21 for ; Wed, 27 Jul 2022 09:29:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230238AbiG0J3b (ORCPT ); Wed, 27 Jul 2022 05:29:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42362 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229691AbiG0J33 (ORCPT ); Wed, 27 Jul 2022 05:29:29 -0400 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 928C147B89; Wed, 27 Jul 2022 02:29:28 -0700 (PDT) Received: from dggpeml500026.china.huawei.com (unknown [172.30.72.54]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4Lt7fv273WzWfq2; Wed, 27 Jul 2022 17:25:27 +0800 (CST) Received: from huawei.com (10.175.101.6) by dggpeml500026.china.huawei.com (7.185.36.106) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Wed, 27 Jul 2022 17:29:15 +0800 From: Zhengchao Shao To: , , , , , , CC: , , , , , , , Subject: [PATCH net-next] net/af_packet: check len when min_header_len equals to 0 Date: Wed, 27 Jul 2022 17:33:12 +0800 Message-ID: <20220727093312.125116-1-shaozhengchao@huawei.com> X-Mailer: git-send-email 2.17.1 MIME-Version: 1.0 X-Originating-IP: [10.175.101.6] X-ClientProxiedBy: dggems705-chm.china.huawei.com (10.3.19.182) To dggpeml500026.china.huawei.com (7.185.36.106) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org User can use AF_PACKET socket to send packets with the length of 0. When min_header_len equals to 0, packet_snd will call __dev_queue_xmit to send packets, and sock->type can be any type. Reported-by: syzbot+5ea725c25d06fb9114c4@syzkaller.appspotmail.com Fixes: fd1894224407 ("bpf: Don't redirect packets with invalid pkt_len") Signed-off-by: Zhengchao Shao --- net/packet/af_packet.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index d08c4728523b..5cbe07116e04 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -3037,8 +3037,8 @@ static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len) if (err) goto out_free; - if (sock->type == SOCK_RAW && - !dev_validate_header(dev, skb->data, len)) { + if ((sock->type == SOCK_RAW && + !dev_validate_header(dev, skb->data, len)) || !skb->len) { err = -EINVAL; goto out_free; }