Commit 14a1c1dc authored Apr 10, 2020 by Xin Long Committed by Greg Kroah-Hartman Jun 03, 2020

xfrm: allow to accept packets with ipv6 NEXTHDR_HOP in xfrm_input



commit afcaf61be9d1dbdee5ec186d1dcc67b6b692180f upstream.

For beet mode, when it's ipv6 inner address with nexthdrs set,
the packet format might be:

    ----------------------------------------------------
    | outer  |     | dest |     |      |  ESP    | ESP |
    | IP hdr | ESP | opts.| TCP | Data | Trailer | ICV |
    ----------------------------------------------------

The nexthdr from ESP could be NEXTHDR_HOP(0), so it should
continue processing the packet when nexthdr returns 0 in
xfrm_input(). Otherwise, when ipv6 nexthdr is set, the
packet will be dropped.

I don't see any error cases that nexthdr may return 0. So
fix it by removing the check for nexthdr == 0.

Fixes: 1da177e4 ("Linux-2.6.12-rc2")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 47dc81ce

net/xfrm/xfrm_input.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -643,7 +643,7 @@ int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
		dev_put(skb->dev);

		spin_lock(&x->lock);
		if (nexthdr <= 0) {
		if (nexthdr < 0) {
		if (nexthdr == -EBADMSG) {
		xfrm_audit_state_icvfail(x, skb,
		x->type->proto);