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 X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,T_DKIMWL_WL_HIGH,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 145D5C282DD for ; Thu, 23 May 2019 19:24:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DF5CD20868 for ; Thu, 23 May 2019 19:24:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1558639443; bh=OFIsjXtbHYZbOt8iZhE+4vMAQY/LFmC8UGgt9t/KYqo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=whEpnyRZxy7OOE9VD52UTZT5g1asRo05GMW/2DzLEYoHL/QChPsbsiIjN2hK3IhcE ASu0uZdlt0eIf5lLBHi0axtuR713UjMDInzKqw8mst52LndI9cLc4Z0xG1JvxOoDwy p9r3Ca/tgPuXfeS+NUgIfeqdHxmPFDLTEWClA0GI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390188AbfEWTYC (ORCPT ); Thu, 23 May 2019 15:24:02 -0400 Received: from mail.kernel.org ([198.145.29.99]:34698 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390797AbfEWTX7 (ORCPT ); Thu, 23 May 2019 15:23:59 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 15AB52054F; Thu, 23 May 2019 19:23:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1558639438; bh=OFIsjXtbHYZbOt8iZhE+4vMAQY/LFmC8UGgt9t/KYqo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=1fnrE7W2adqlwh2Wzx33dgH1CXBm7mZDkXc8e29yHdMaUFjSk1AQVnHeRYoqMLVS3 XDKxUr6LtRX6Hq+Ut1RIQmILDOGAliOiwzAHSyEWAQsbwLLyu5X+Z3KnumdbKpscJI s4bSL33DN45+/KFFGF1YVPFPbwu4R1m8dMIm2Wk8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Sabrina Dubroca , Steffen Klassert , Sasha Levin Subject: [PATCH 5.0 105/139] esp4: add length check for UDP encapsulation Date: Thu, 23 May 2019 21:06:33 +0200 Message-Id: <20190523181733.974550825@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190523181720.120897565@linuxfoundation.org> References: <20190523181720.120897565@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org [ Upstream commit 8dfb4eba4100e7cdd161a8baef2d8d61b7a7e62e ] esp_output_udp_encap can produce a length that doesn't fit in the 16 bits of a UDP header's length field. In that case, we'll send a fragmented packet whose length is larger than IP_MAX_MTU (resulting in "Oversized IP packet" warnings on receive) and with a bogus UDP length. To prevent this, add a length check to esp_output_udp_encap and return -EMSGSIZE on failure. This seems to be older than git history. Signed-off-by: Sabrina Dubroca Signed-off-by: Steffen Klassert Signed-off-by: Sasha Levin --- net/ipv4/esp4.c | 20 +++++++++++++++----- 1 file changed, 15 insertions(+), 5 deletions(-) diff --git a/net/ipv4/esp4.c b/net/ipv4/esp4.c index 10e809b296ec8..fb065a8937ea2 100644 --- a/net/ipv4/esp4.c +++ b/net/ipv4/esp4.c @@ -226,7 +226,7 @@ static void esp_output_fill_trailer(u8 *tail, int tfclen, int plen, __u8 proto) tail[plen - 1] = proto; } -static void esp_output_udp_encap(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp) +static int esp_output_udp_encap(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp) { int encap_type; struct udphdr *uh; @@ -234,6 +234,7 @@ static void esp_output_udp_encap(struct xfrm_state *x, struct sk_buff *skb, stru __be16 sport, dport; struct xfrm_encap_tmpl *encap = x->encap; struct ip_esp_hdr *esph = esp->esph; + unsigned int len; spin_lock_bh(&x->lock); sport = encap->encap_sport; @@ -241,11 +242,14 @@ static void esp_output_udp_encap(struct xfrm_state *x, struct sk_buff *skb, stru encap_type = encap->encap_type; spin_unlock_bh(&x->lock); + len = skb->len + esp->tailen - skb_transport_offset(skb); + if (len + sizeof(struct iphdr) >= IP_MAX_MTU) + return -EMSGSIZE; + uh = (struct udphdr *)esph; uh->source = sport; uh->dest = dport; - uh->len = htons(skb->len + esp->tailen - - skb_transport_offset(skb)); + uh->len = htons(len); uh->check = 0; switch (encap_type) { @@ -262,6 +266,8 @@ static void esp_output_udp_encap(struct xfrm_state *x, struct sk_buff *skb, stru *skb_mac_header(skb) = IPPROTO_UDP; esp->esph = esph; + + return 0; } int esp_output_head(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp) @@ -275,8 +281,12 @@ int esp_output_head(struct xfrm_state *x, struct sk_buff *skb, struct esp_info * int tailen = esp->tailen; /* this is non-NULL only with UDP Encapsulation */ - if (x->encap) - esp_output_udp_encap(x, skb, esp); + if (x->encap) { + int err = esp_output_udp_encap(x, skb, esp); + + if (err < 0) + return err; + } if (!skb_cloned(skb)) { if (tailen <= skb_tailroom(skb)) { -- 2.20.1