netdev - [PATCH 03/15] esp6: get the right proto for transport mode in esp6_gso

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20200529110408.6349-4-steffen.klassert@secunet.com>
Date:   Fri, 29 May 2020 13:03:56 +0200
From:   Steffen Klassert <steffen.klassert@...unet.com>
To:     David Miller <davem@...emloft.net>
CC:     Herbert Xu <herbert@...dor.apana.org.au>,
        Steffen Klassert <steffen.klassert@...unet.com>,
        <netdev@...r.kernel.org>
Subject: [PATCH 03/15] esp6: get the right proto for transport mode in esp6_gso_encap

From: Xin Long <lucien.xin@...il.com>

For transport mode, when ipv6 nexthdr is set, the packet format might
be like:

    ----------------------------------------------------
    |        | dest |     |     |      |  ESP    | ESP |
    | IP6 hdr| opts.| ESP | TCP | Data | Trailer | ICV |
    ----------------------------------------------------

What it wants to get for x-proto in esp6_gso_encap() is the proto that
will be set in ESP nexthdr. So it should skip all ipv6 nexthdrs and
get the real transport protocol. Othersize, the wrong proto number
will be set into ESP nexthdr.

This patch is to skip all ipv6 nexthdrs by calling ipv6_skip_exthdr()
in esp6_gso_encap().

Fixes: 7862b4058b9f ("esp: Add gso handlers for esp4 and esp6")
Signed-off-by: Xin Long <lucien.xin@...il.com>
Signed-off-by: Steffen Klassert <steffen.klassert@...unet.com>
---
 net/ipv6/esp6_offload.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/net/ipv6/esp6_offload.c b/net/ipv6/esp6_offload.c
index 8eab2c869d61..b82850886574 100644
--- a/net/ipv6/esp6_offload.c
+++ b/net/ipv6/esp6_offload.c
@@ -123,9 +123,16 @@ static void esp6_gso_encap(struct xfrm_state *x, struct sk_buff *skb)
 	struct ip_esp_hdr *esph;
 	struct ipv6hdr *iph = ipv6_hdr(skb);
 	struct xfrm_offload *xo = xfrm_offload(skb);
-	int proto = iph->nexthdr;
+	u8 proto = iph->nexthdr;
 
 	skb_push(skb, -skb_network_offset(skb));
+
+	if (x->outer_mode.encap == XFRM_MODE_TRANSPORT) {
+		__be16 frag;
+
+		ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &proto, &frag);
+	}
+
 	esph = ip_esp_hdr(skb);
 	*skb_mac_header(skb) = IPPROTO_ESP;
 
-- 
2.17.1