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 89348C433F5 for ; Wed, 24 Nov 2021 13:53:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1353020AbhKXN4g (ORCPT ); Wed, 24 Nov 2021 08:56:36 -0500 Received: from mail.kernel.org ([198.145.29.99]:42104 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1354769AbhKXNxA (ORCPT ); Wed, 24 Nov 2021 08:53:00 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 1EC15613B3; Wed, 24 Nov 2021 13:05:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1637759125; bh=ee/oxOG10r60OQVE/MVsKaIcAHlITCdIz3QlzjqV2sE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ubHhDJZzPrmGxCFJTnzE5mZUruo9cfaoU2Y7UaQig/S1lASaZfkY6skepu3py7xE1 tVfPdKTnqEUiOPMupoTTakVWGtK5o96c8Xe8GtqiIZYIt/zZY3sQnaMyBsTP/rAJtk pcnhiat7CzXrjp8lDGBBDf8XHaHHJSChsZs7NNp4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Daniel Borkmann , Cong Wang , John Fastabend , Sasha Levin Subject: [PATCH 5.15 140/279] udp: Validate checksum in udp_read_sock() Date: Wed, 24 Nov 2021 12:57:07 +0100 Message-Id: <20211124115723.620795552@linuxfoundation.org> X-Mailer: git-send-email 2.34.0 In-Reply-To: <20211124115718.776172708@linuxfoundation.org> References: <20211124115718.776172708@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Cong Wang [ Upstream commit 099f896f498a2b26d84f4ddae039b2c542c18b48 ] It turns out the skb's in sock receive queue could have bad checksums, as both ->poll() and ->recvmsg() validate checksums. We have to do the same for ->read_sock() path too before they are redirected in sockmap. Fixes: d7f571188ecf ("udp: Implement ->read_sock() for sockmap") Reported-by: Daniel Borkmann Signed-off-by: Cong Wang Signed-off-by: Daniel Borkmann Acked-by: John Fastabend Link: https://lore.kernel.org/bpf/20211115044006.26068-1-xiyou.wangcong@gmail.com Signed-off-by: Sasha Levin --- net/ipv4/udp.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index 2fffcf2b54f3f..2ce3fca545d37 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -1808,6 +1808,17 @@ int udp_read_sock(struct sock *sk, read_descriptor_t *desc, skb = skb_recv_udp(sk, 0, 1, &err); if (!skb) return err; + + if (udp_lib_checksum_complete(skb)) { + __UDP_INC_STATS(sock_net(sk), UDP_MIB_CSUMERRORS, + IS_UDPLITE(sk)); + __UDP_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, + IS_UDPLITE(sk)); + atomic_inc(&sk->sk_drops); + kfree_skb(skb); + continue; + } + used = recv_actor(desc, skb, 0, skb->len); if (used <= 0) { if (!copied) -- 2.33.0