linux/net/ipv4
Shmulik Ladkani c0451fe1f2 net: ip_finish_output_gso: Allow fragmenting segments of tunneled skbs if their DF is unset
In b8247f095e,

   "net: ip_finish_output_gso: If skb_gso_network_seglen exceeds MTU, allow segmentation for local udp tunneled skbs"

gso skbs arriving from an ingress interface that go through UDP
tunneling, are allowed to be fragmented if the resulting encapulated
segments exceed the dst mtu of the egress interface.

This aligned the behavior of gso skbs to non-gso skbs going through udp
encapsulation path.

However the non-gso vs gso anomaly is present also in the following
cases of a GRE tunnel:
 - ip_gre in collect_md mode, where TUNNEL_DONT_FRAGMENT is not set
   (e.g. OvS vport-gre with df_default=false)
 - ip_gre in nopmtudisc mode, where IFLA_GRE_IGNORE_DF is set

In both of the above cases, the non-gso skbs get fragmented, whereas the
gso skbs (having skb_gso_network_seglen that exceeds dst mtu) get dropped,
as they don't go through the segment+fragment code path.

Fix: Setting IPSKB_FRAG_SEGS if the tunnel specified IP_DF bit is NOT set.

Tunnels that do set IP_DF, will not go to fragmentation of segments.
This preserves behavior of ip_gre in (the default) pmtudisc mode.

Fixes: b8247f095e ("net: ip_finish_output_gso: If skb_gso_network_seglen exceeds MTU, allow segmentation for local udp tunneled skbs")
Reported-by: wenxu <wenxu@ucloud.cn>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Tested-by: wenxu <wenxu@ucloud.cn>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-22 17:11:01 -07:00
..
netfilter netfilter: x_tables: speed up jump target validation 2016-07-18 21:35:23 +02:00
af_inet.c ipv4: af_inet: make it explicitly non-modular 2016-07-11 22:44:26 -07:00
ah4.c ah4: Fix error return in ah_input(). 2015-08-25 13:38:50 -07:00
arp.c net: rename NET_{ADD|INC}_STATS_BH() 2016-04-27 22:48:24 -04:00
cipso_ipv4.c Merge branch 'stable-4.8' of git://git.infradead.org/users/pcmoore/selinux into next 2016-07-07 10:15:34 +10:00
datagram.c net: Set sk_txhash from a random number 2015-07-29 22:44:04 -07:00
devinet.c ipv4: do not abuse GFP_ATOMIC in inet_netconf_notify_devconf() 2016-07-09 18:12:25 -04:00
esp4.c esp: Fix ESN generation under UDP encapsulation 2016-06-23 11:52:00 -04:00
fib_frontend.c net: vrf: Create FIB tables on link create 2016-05-06 15:51:47 -04:00
fib_lookup.h ipv4: consider TOS in fib_select_default 2015-07-24 22:46:11 -07:00
fib_rules.c net: Add l3mdev rule 2016-06-08 11:36:02 -07:00
fib_semantics.c ipv4: reject RTNH_F_DEAD and RTNH_F_LINKDOWN from user space 2016-07-11 13:41:09 -07:00
fib_trie.c fib_trie: Fix the description of pos and bits 2016-08-18 23:51:23 -07:00
fou.c gue: Implement direction IP encapsulation 2016-06-07 23:51:14 -07:00
gre_demux.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-06-30 05:03:36 -04:00
gre_offload.c gso: Remove arbitrary checks for unsupported GSO 2016-05-20 18:03:15 -04:00
icmp.c net: icmp: rename ICMPMSGIN_INC_STATS_BH() 2016-04-27 22:48:23 -04:00
igmp.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-03-08 12:34:12 -05:00
inet_connection_sock.c timers, net/ipv4/inet: Initialize connection request timers as pinned 2016-07-07 10:35:06 +02:00
inet_diag.c net: diag: Add support to filter on device index 2016-06-28 05:25:04 -04:00
inet_fragment.c net: disable fragment reassembly if high_thresh is zero 2016-06-05 22:56:42 -04:00
inet_hashtables.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-05-04 00:52:29 -04:00
inet_timewait_sock.c timers, net/ipv4/inet: Initialize connection request timers as pinned 2016-07-07 10:35:06 +02:00
inetpeer.c net: Add helper function to compare inetpeer addresses 2015-08-28 13:32:36 -07:00
ip_forward.c net/ipv4: Introduce IPSKB_FRAG_SEGS bit to inet_skb_parm.flags 2016-07-19 16:40:22 -07:00
ip_fragment.c net: rename IP_INC_STATS_BH() 2016-04-27 22:48:23 -04:00
ip_gre.c gre: set inner_protocol on xmit 2016-08-15 13:37:12 -07:00
ip_input.c net: original ingress device index in PKTINFO 2016-05-11 19:31:40 -04:00
ip_options.c net: ipv4: Convert IP network timestamps to be y2038 safe 2016-03-01 17:18:44 -05:00
ip_output.c net/ipv4: Introduce IPSKB_FRAG_SEGS bit to inet_skb_parm.flags 2016-07-19 16:40:22 -07:00
ip_sockglue.c sock: propagate __sock_cmsg_send() error 2016-05-16 13:46:23 -04:00
ip_tunnel_core.c net: ip_finish_output_gso: Allow fragmenting segments of tunneled skbs if their DF is unset 2016-08-22 17:11:01 -07:00
ip_tunnel.c net: ipv4: Add ability to have GRE ignore DF bit in IPv4 payloads 2016-06-15 21:39:59 -07:00
ip_vti.c vti: flush x-netns xfrm cache when vti interface is removed 2016-08-09 12:57:49 -07:00
ipcomp.c
ipconfig.c ipconfig: Protect ic_addrservaddr with IPCONFIG_DYNAMIC. 2016-06-11 20:40:24 -07:00
ipip.c ipip: support MPLS over IPv4 2016-07-09 17:45:56 -04:00
ipmr.c net: ipmr/ip6mr: update lastuse on entry change 2016-07-26 15:18:31 -07:00
Kconfig tcp: add NV congestion control 2016-06-10 23:07:49 -07:00
Makefile tcp: add NV congestion control 2016-06-10 23:07:49 -07:00
netfilter.c ipv4: Pass struct net into ip_route_me_harder 2015-09-29 20:21:32 +02:00
ping.c sock: enable timestamping using control messages 2016-04-04 15:50:30 -04:00
proc.c ipv4: Namespaceify ip_default_ttl sysctl knob 2016-02-16 20:42:54 -05:00
protocol.c
raw.c sock: enable timestamping using control messages 2016-04-04 15:50:30 -04:00
route.c net: l3mdev: Allow send on enslaved interface 2016-05-09 22:33:52 -04:00
syncookies.c net: rename NET_{ADD|INC}_STATS_BH() 2016-04-27 22:48:24 -04:00
sysctl_net_ipv4.c ipv4: Fix non-initialized TTL when CONFIG_SYSCTL=n 2016-05-23 14:32:06 -07:00
tcp_bic.c tcp: replace cnt & rtt with struct in pkts_acked() 2016-05-11 14:43:19 -04:00
tcp_cdg.c tcp: replace cnt & rtt with struct in pkts_acked() 2016-05-11 14:43:19 -04:00
tcp_cong.c tcp: remove tcp_ecn_make_synack() socket argument 2015-09-25 13:00:38 -07:00
tcp_cubic.c tcp: replace cnt & rtt with struct in pkts_acked() 2016-05-11 14:43:19 -04:00
tcp_dctcp.c tcp: return sizeof tcp_dctcp_info in dctcp_get_info() 2016-06-14 23:46:30 -07:00
tcp_diag.c net: diag: Support destroying TCP sockets. 2015-12-15 23:26:52 -05:00
tcp_fastopen.c tcp: do not assume TCP code is non preemptible 2016-05-02 17:02:25 -04:00
tcp_highspeed.c tcp: add tcp_in_slow_start helper 2015-07-09 14:22:52 -07:00
tcp_htcp.c tcp: replace cnt & rtt with struct in pkts_acked() 2016-05-11 14:43:19 -04:00
tcp_hybla.c tcp: do not slow start when cwnd equals ssthresh 2015-07-09 14:22:52 -07:00
tcp_illinois.c tcp: replace cnt & rtt with struct in pkts_acked() 2016-05-11 14:43:19 -04:00
tcp_input.c Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2016-07-29 17:38:46 -07:00
tcp_ipv4.c tcp: md5: use kmalloc() backed scratch areas 2016-07-01 04:02:55 -04:00
tcp_lp.c tcp: replace cnt & rtt with struct in pkts_acked() 2016-05-11 14:43:19 -04:00
tcp_metrics.c libnl: nla_put_msecs(): align on a 64-bit area 2016-04-23 20:13:24 -04:00
tcp_minisocks.c tcp: do not assume TCP code is non preemptible 2016-05-02 17:02:25 -04:00
tcp_nv.c tcp: add NV congestion control 2016-06-10 23:07:49 -07:00
tcp_offload.c gso: Remove arbitrary checks for unsupported GSO 2016-05-20 18:03:15 -04:00
tcp_output.c tcp: consider recv buf for the initial window scale 2016-07-30 21:21:57 -07:00
tcp_probe.c net: ipv4: tcp_probe: Replace timespec with timespec64 2016-03-01 17:18:44 -05:00
tcp_recovery.c tcp: do not assume TCP code is non preemptible 2016-05-02 17:02:25 -04:00
tcp_scalable.c tcp: add tcp_in_slow_start helper 2015-07-09 14:22:52 -07:00
tcp_timer.c tcp_timer.c: Add kernel-doc function descriptions 2016-07-15 23:18:14 -07:00
tcp_vegas.c tcp: replace cnt & rtt with struct in pkts_acked() 2016-05-11 14:43:19 -04:00
tcp_vegas.h tcp: replace cnt & rtt with struct in pkts_acked() 2016-05-11 14:43:19 -04:00
tcp_veno.c tcp: replace cnt & rtt with struct in pkts_acked() 2016-05-11 14:43:19 -04:00
tcp_westwood.c tcp: replace cnt & rtt with struct in pkts_acked() 2016-05-11 14:43:19 -04:00
tcp_yeah.c tcp: replace cnt & rtt with struct in pkts_acked() 2016-05-11 14:43:19 -04:00
tcp.c tcp: md5: use kmalloc() backed scratch areas 2016-07-01 04:02:55 -04:00
tunnel4.c tunnels: correct conditional build of MPLS and IPv6 2016-07-11 13:27:06 -07:00
udp_diag.c udp: no longer use SLAB_DESTROY_BY_RCU 2016-04-04 22:11:19 -04:00
udp_impl.h
udp_offload.c gso: Remove arbitrary checks for unsupported GSO 2016-05-20 18:03:15 -04:00
udp_tunnel.c net: Remove deprecated tunnel specific UDP offload functions 2016-06-17 20:23:32 -07:00
udp.c udp: use sk_filter_trim_cap for udp{,6}_queue_rcv_skb 2016-07-25 21:40:33 -07:00
udplite.c
xfrm4_input.c netfilter: Pass net into okfn 2015-09-17 17:18:37 -07:00
xfrm4_mode_beet.c
xfrm4_mode_transport.c
xfrm4_mode_tunnel.c
xfrm4_output.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-10-24 06:54:12 -07:00
xfrm4_policy.c net: xfrm: fix old-style declaration 2016-06-16 22:06:30 -07:00
xfrm4_protocol.c
xfrm4_state.c
xfrm4_tunnel.c