linux/net
Florian Westphal 485fca664d ipv6: don't increase size when refragmenting forwarded ipv6 skbs
since commit 6aafeef03b ("netfilter: push reasm skb through instead of
original frag skbs") we will end up sometimes re-fragmenting skbs
that we've reassembled.

ipv6 defrag preserves the original skbs using the skb frag list, i.e. as long
as the skb frag list is preserved there is no problem since we keep
original geometry of fragments intact.

However, in the rare case where the frag list is munged or skb
is linearized, we might send larger fragments than what we originally
received.

A router in the path might then send packet-too-big errors even if
sender never sent fragments exceeding the reported mtu:

mtu 1500 - 1500:1400 - 1400:1280 - 1280
     A         R1         R2        B

1 - A sends to B, fragment size 1400
2 - R2 sends pkttoobig error for 1280
3 - A sends to B, fragment size 1280
4 - R2 sends pkttoobig error for 1280 again because it sees fragments of size 1400.

make sure ip6_fragment always caps MTU at largest packet size seen
when defragmented skb is forwarded.

Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-25 17:22:23 -04:00
..
6lowpan 6lowpan: nhc: add other known rfc6282 compressions 2015-02-14 23:08:44 +01:00
9p 9p: patches for 4.1 merge window 2015-04-18 17:45:30 -04:00
802 net: Kill dev_rebuild_header 2015-03-02 16:43:41 -05:00
8021q vlan: Correctly propagate promisc|allmulti flags in notifier. 2015-05-14 00:54:32 -04:00
appletalk net: Pass kern from net_proto_family.create to sk_alloc 2015-05-11 10:50:17 -04:00
atm net: Pass kern from net_proto_family.create to sk_alloc 2015-05-11 10:50:17 -04:00
ax25 net: Pass kern from net_proto_family.create to sk_alloc 2015-05-11 10:50:17 -04:00
batman-adv dev: introduce dev_get_iflink() 2015-04-02 14:04:59 -04:00
bluetooth ipv6: Remove external dependency on rt6i_gateway and RTF_ANYCAST 2015-05-25 13:25:33 -04:00
bridge Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-05-23 01:22:35 -04:00
caif net: Pass kern from net_proto_family.create to sk_alloc 2015-05-11 10:50:17 -04:00
can net: Pass kern from net_proto_family.create to sk_alloc 2015-05-11 10:50:17 -04:00
ceph net: Add a struct net parameter to sock_create_kern 2015-05-11 10:50:17 -04:00
core net: af_unix: implement splice for stream af_unix sockets 2015-05-25 00:06:59 -04:00
dcb net/dcb: Add IEEE QCN attribute 2015-03-06 21:50:02 -05:00
dccp inet: fix possible panic in reqsk_queue_unlink() 2015-04-24 11:39:15 -04:00
decnet net: Pass kern from net_proto_family.create to sk_alloc 2015-05-11 10:50:17 -04:00
dns_resolver
dsa switchdev: don't use anonymous union on switchdev attr/obj structs 2015-05-13 14:20:59 -04:00
ethernet flow_dissect: use programable dissector in skb_flow_dissect and friends 2015-05-13 15:19:47 -04:00
hsr net/hsr: Fix NULL pointer dereference and refcnt bugs when deleting a HSR interface. 2015-03-01 13:40:23 -05:00
ieee802154 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-05-13 14:31:43 -04:00
ipv4 ip: reject too-big defragmented DF-skb when forwarding 2015-05-25 00:08:48 -04:00
ipv6 ipv6: don't increase size when refragmenting forwarded ipv6 skbs 2015-05-25 17:22:23 -04:00
ipx net: Pass kern from net_proto_family.create to sk_alloc 2015-05-11 10:50:17 -04:00
irda net: Pass kern from net_proto_family.create to sk_alloc 2015-05-11 10:50:17 -04:00
iucv net: Pass kern from net_proto_family.create to sk_alloc 2015-05-11 10:50:17 -04:00
key net: Pass kern from net_proto_family.create to sk_alloc 2015-05-11 10:50:17 -04:00
l2tp net: Modify sk_alloc to not reference count the netns of kernel sockets. 2015-05-11 10:50:18 -04:00
lapb
llc net: Pass kern from net_proto_family.create to sk_alloc 2015-05-11 10:50:17 -04:00
mac80211 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-05-23 01:22:35 -04:00
mac802154 Merge branch 'for-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth 2015-05-09 15:51:00 -04:00
mpls mpls: Change reserved label names to be consistent with netbsd 2015-05-09 22:29:50 -04:00
netfilter ipv6: Set FLOWI_FLAG_KNOWN_NH at flowi6_flags 2015-05-25 13:25:34 -04:00
netlabel netlink: implement nla_put_in_addr and nla_put_in6_addr 2015-03-31 13:58:35 -04:00
netlink Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-05-23 01:22:35 -04:00
netrom net: Pass kern from net_proto_family.create to sk_alloc 2015-05-11 10:50:17 -04:00
nfc net: Pass kern from net_proto_family.create to sk_alloc 2015-05-11 10:50:17 -04:00
openvswitch geneve: Rename support library as geneve_core 2015-05-13 15:59:13 -04:00
packet net-packet: fix null pointer exception in rollover mode 2015-05-17 22:41:38 -04:00
phonet net: Pass kern from net_proto_family.create to sk_alloc 2015-05-11 10:50:17 -04:00
rds Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-05-13 14:31:43 -04:00
rfkill
rose net: Pass kern from net_proto_family.create to sk_alloc 2015-05-11 10:50:17 -04:00
rxrpc net: Pass kern from net_proto_family.create to sk_alloc 2015-05-11 10:50:17 -04:00
sched Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-05-23 01:22:35 -04:00
sctp ipv6: Add rt6_get_cookie() function 2015-05-25 13:25:34 -04:00
sunrpc svcrpc: fix potential GSSX_ACCEPT_SEC_CONTEXT decoding failures 2015-05-04 12:02:40 -04:00
switchdev Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-05-23 01:22:35 -04:00
tipc tipc: use sock_create_kern interface to create kernel socket 2015-05-14 13:39:33 -04:00
unix net: af_unix: implement splice for stream af_unix sockets 2015-05-25 00:06:59 -04:00
vmw_vsock net: Pass kern from net_proto_family.create to sk_alloc 2015-05-11 10:50:17 -04:00
wimax
wireless cfg80211: change GO_CONCURRENT to IR_CONCURRENT for STA 2015-05-06 15:50:02 +02:00
x25 net: Pass kern from net_proto_family.create to sk_alloc 2015-05-11 10:50:17 -04:00
xfrm net: make skb_dst_pop routine static 2015-05-12 23:19:49 -04:00
Kconfig net: add CONFIG_NET_INGRESS to enable ingress filtering 2015-05-14 01:10:05 -04:00
Makefile mpls: Refactor how the mpls module is built 2015-03-04 00:26:06 -05:00
compat.c net: switch importing msghdr from userland to {compat_,}import_iovec() 2015-04-09 00:02:26 -04:00
socket.c net: Add a struct net parameter to sock_create_kern 2015-05-11 10:50:17 -04:00
sysctl_net.c