linux/net
Herbert Xu 23ca0c989e ipip: Fix handling of DF packets when pmtudisc is OFF
RFC 2003 requires the outer header to have DF set if DF is set
on the inner header, even when PMTU discovery is off for the
tunnel.  Our implementation does exactly that.

For this to work properly the IPIP gateway also needs to engate
in PMTU when the inner DF bit is set.  As otherwise the original
host would not be able to carry out its PMTU successfully since
part of the path is only visible to the gateway.

Unfortunately when the tunnel PMTU discovery setting is off, we
do not collect the necessary soft state, resulting in blackholes
when the original host tries to perform PMTU discovery.

This problem is not reproducible on the IPIP gateway itself as
the inner packet usually has skb->local_df set.  This is not
correctly cleared (an unrelated bug) when the packet passes
through the tunnel, which allows fragmentation to occur.  For
hosts behind the IPIP gateway it is readily visible with a simple
ping.

This patch fixes the problem by performing PMTU discovery for
all packets with the inner DF bit set, regardless of the PMTU
discovery setting on the tunnel itself.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-11-06 20:33:40 -08:00
..
9p virtio: add virtio IDs file 2009-09-23 22:26:32 +09:30
802 net: remove COMPAT_NET_DEV_OPS 2009-05-25 01:53:53 -07:00
8021q net: fix vlan_get_size to include vlan_flags size 2009-09-26 20:16:07 -07:00
appletalk Have atalk_route_packet() return NET_RX_SUCCESS not NET_XMIT_SUCCESS 2009-09-14 17:02:47 -07:00
atm net: Make setsockopt() optlen be unsigned. 2009-09-30 16:12:20 -07:00
ax25 ax25: Fix possible oops in ax25_make_new 2009-09-30 16:44:12 -07:00
bluetooth bluetooth: static lock key fix 2009-10-19 19:36:49 -07:00
bridge bridge: prevent bridging wrong device 2009-11-05 20:46:52 -08:00
can net: Make setsockopt() optlen be unsigned. 2009-09-30 16:12:20 -07:00
core net: fix sk_forward_alloc corruption 2009-10-30 12:25:12 -07:00
dcb net: fix double skb free in dcbnl 2009-09-26 20:16:15 -07:00
dccp net: Make setsockopt() optlen be unsigned. 2009-09-30 16:12:20 -07:00
decnet decnet: netdevice refcount leak 2009-11-06 00:50:39 -08:00
dsa netdev: convert pseudo-devices to netdev_tx_t 2009-09-01 01:13:07 -07:00
econet Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 2009-08-12 17:44:53 -07:00
ethernet net: remove COMPAT_NET_DEV_OPS 2009-05-25 01:53:53 -07:00
ieee802154 net: Make setsockopt() optlen be unsigned. 2009-09-30 16:12:20 -07:00
ipv4 ipip: Fix handling of DF packets when pmtudisc is OFF 2009-11-06 20:33:40 -08:00
ipv6 net: fix sk_forward_alloc corruption 2009-10-30 12:25:12 -07:00
ipx net: Make setsockopt() optlen be unsigned. 2009-09-30 16:12:20 -07:00
irda net: Make setsockopt() optlen be unsigned. 2009-09-30 16:12:20 -07:00
iucv net: Make setsockopt() optlen be unsigned. 2009-09-30 16:12:20 -07:00
key net: file_operations should be const 2009-09-02 01:03:53 -07:00
lapb net: remove NET_RX_BAD and NET_RX_CN* defines 2009-07-05 19:15:35 -07:00
llc net: Make setsockopt() optlen be unsigned. 2009-09-30 16:12:20 -07:00
mac80211 mac80211: check interface is down before type change 2009-11-02 15:14:07 -05:00
netfilter netfilter: xt_connlimit: fix regression caused by zero family value 2009-11-06 18:08:32 -08:00
netlabel Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 2009-07-30 19:22:43 -07:00
netlink net: Make setsockopt() optlen be unsigned. 2009-09-30 16:12:20 -07:00
netrom net: Make setsockopt() optlen be unsigned. 2009-09-30 16:12:20 -07:00
packet net: Fix 'Re: PACKET_TX_RING: packet size is too long' 2009-10-29 03:19:11 -07:00
phonet Phonet: fix mutex imbalance 2009-09-30 16:41:34 -07:00
rds net: Make setsockopt() optlen be unsigned. 2009-09-30 16:12:20 -07:00
rfkill rfkill: add the GPS radio type 2009-08-04 16:44:23 -04:00
rose rose: device refcount leak 2009-11-05 20:56:07 -08:00
rxrpc net: Make setsockopt() optlen be unsigned. 2009-09-30 16:12:20 -07:00
sched pkt_sched: pedit use proper struct 2009-10-11 23:03:47 -07:00
sctp net: Make setsockopt() optlen be unsigned. 2009-09-30 16:12:20 -07:00
sunrpc net: fix sk_forward_alloc corruption 2009-10-30 12:25:12 -07:00
tipc net: Make setsockopt() optlen be unsigned. 2009-09-30 16:12:20 -07:00
unix AF_UNIX: Fix deadlock on connecting to shutdown socket 2009-10-18 23:17:37 -07:00
wanrouter headers: smp_lock.h redux 2009-07-12 12:22:34 -07:00
wimax wimax: fix warning caused by not checking retval of rfkill_set_hw_state() 2009-06-11 11:12:48 -07:00
wireless cfg80211: fix NULL ptr deref 2009-11-02 15:14:07 -05:00
x25 net: Make setsockopt() optlen be unsigned. 2009-09-30 16:12:20 -07:00
xfrm net: file_operations should be const 2009-09-02 01:03:53 -07:00
compat.c net: Make setsockopt() optlen be unsigned. 2009-09-30 16:12:20 -07:00
Kconfig net/compat/wext: send different messages to compat tasks 2009-07-15 08:53:39 -07:00
Makefile net: remove redundant sched/ in net/Makefile 2009-07-12 20:11:14 -07:00
nonet.c
socket.c net: Make setsockopt() optlen be unsigned. 2009-09-30 16:12:20 -07:00
sysctl_net.c net: sysctl_net - use net_eq to compare nets 2009-03-16 16:23:30 +01:00
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