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: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
afcaf61be9