diff options
author | Jakub Sitnicki <jkbs@redhat.com> | 2016-10-26 12:21:14 +0300 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2016-10-31 20:10:41 +0300 |
commit | f89c56ce710afa65e1b2ead555b52c4807f34ff7 (patch) | |
tree | 7a639f5cfdb6484d8983ecd6248f5cca31b98296 /net/ipv6/ip6_output.c | |
parent | b9a321b48af40e0606009df8aff0a8c65dfbbfd8 (diff) | |
download | linux-f89c56ce710afa65e1b2ead555b52c4807f34ff7.tar.xz |
ipv6: Don't use ufo handling on later transformed packets
Similar to commit c146066ab802 ("ipv4: Don't use ufo handling on later
transformed packets"), don't perform UFO on packets that will be IPsec
transformed. To detect it we rely on the fact that headerlen in
dst_entry is non-zero only for transformation bundles (xfrm_dst
objects).
Unwanted segmentation can be observed with a NETIF_F_UFO capable device,
such as a dummy device:
DEV=dum0 LEN=1493
ip li add $DEV type dummy
ip addr add fc00::1/64 dev $DEV nodad
ip link set $DEV up
ip xfrm policy add dir out src fc00::1 dst fc00::2 \
tmpl src fc00::1 dst fc00::2 proto esp spi 1
ip xfrm state add src fc00::1 dst fc00::2 \
proto esp spi 1 enc 'aes' 0x0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b
tcpdump -n -nn -i $DEV -t &
socat /dev/zero,readbytes=$LEN udp6:[fc00::2]:$LEN
tcpdump output before:
IP6 fc00::1 > fc00::2: frag (0|1448) ESP(spi=0x00000001,seq=0x1), length 1448
IP6 fc00::1 > fc00::2: frag (1448|48)
IP6 fc00::1 > fc00::2: ESP(spi=0x00000001,seq=0x2), length 88
... and after:
IP6 fc00::1 > fc00::2: frag (0|1448) ESP(spi=0x00000001,seq=0x1), length 1448
IP6 fc00::1 > fc00::2: frag (1448|80)
Fixes: e89e9cf539a2 ("[IPv4/IPv6]: UFO Scatter-gather approach")
Signed-off-by: Jakub Sitnicki <jkbs@redhat.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv6/ip6_output.c')
-rw-r--r-- | net/ipv6/ip6_output.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c index 6001e781164e..59eb4ed99ce8 100644 --- a/net/ipv6/ip6_output.c +++ b/net/ipv6/ip6_output.c @@ -1366,7 +1366,7 @@ emsgsize: if (((length > mtu) || (skb && skb_is_gso(skb))) && (sk->sk_protocol == IPPROTO_UDP) && - (rt->dst.dev->features & NETIF_F_UFO) && + (rt->dst.dev->features & NETIF_F_UFO) && !rt->dst.header_len && (sk->sk_type == SOCK_DGRAM) && !udp_get_no_check6_tx(sk)) { err = ip6_ufo_append_data(sk, queue, getfrag, from, length, hh_len, fragheaderlen, exthdrlen, |