linux/net/core
Jay Vosburgh 2c26d34bbc net/core: Handle csum for CHECKSUM_COMPLETE VXLAN forwarding
When using VXLAN tunnels and a sky2 device, I have experienced
checksum failures of the following type:

[ 4297.761899] eth0: hw csum failure
[...]
[ 4297.765223] Call Trace:
[ 4297.765224]  <IRQ>  [<ffffffff8172f026>] dump_stack+0x46/0x58
[ 4297.765235]  [<ffffffff8162ba52>] netdev_rx_csum_fault+0x42/0x50
[ 4297.765238]  [<ffffffff8161c1a0>] ? skb_push+0x40/0x40
[ 4297.765240]  [<ffffffff8162325c>] __skb_checksum_complete+0xbc/0xd0
[ 4297.765243]  [<ffffffff8168c602>] tcp_v4_rcv+0x2e2/0x950
[ 4297.765246]  [<ffffffff81666ca0>] ? ip_rcv_finish+0x360/0x360

	These are reliably reproduced in a network topology of:

container:eth0 == host(OVS VXLAN on VLAN) == bond0 == eth0 (sky2) -> switch

	When VXLAN encapsulated traffic is received from a similarly
configured peer, the above warning is generated in the receive
processing of the encapsulated packet.  Note that the warning is
associated with the container eth0.

        The skbs from sky2 have ip_summed set to CHECKSUM_COMPLETE, and
because the packet is an encapsulated Ethernet frame, the checksum
generated by the hardware includes the inner protocol and Ethernet
headers.

	The receive code is careful to update the skb->csum, except in
__dev_forward_skb, as called by dev_forward_skb.  __dev_forward_skb
calls eth_type_trans, which in turn calls skb_pull_inline(skb, ETH_HLEN)
to skip over the Ethernet header, but does not update skb->csum when
doing so.

	This patch resolves the problem by adding a call to
skb_postpull_rcsum to update the skb->csum after the call to
eth_type_trans.

Signed-off-by: Jay Vosburgh <jay.vosburgh@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-26 16:16:51 -05:00
..
datagram.c skb_copy_datagram_iovec() can die 2014-12-09 16:29:11 -05:00
dev_addr_lists.c net: fix spelling for synchronized 2014-11-18 15:26:32 -05:00
dev_ioctl.c dev_ioctl: use sizeof(x) instead of sizeof x 2014-11-18 15:27:32 -05:00
dev.c net/core: Handle csum for CHECKSUM_COMPLETE VXLAN forwarding 2014-12-26 16:16:51 -05:00
drop_monitor.c net: Replace get_cpu_var through this_cpu_ptr 2014-08-26 13:45:47 -04:00
dst.c dst: no need to take reference on DST_NOCACHE dsts 2014-12-09 16:08:17 -05:00
ethtool.c ethtool: Support for configurable RSS hash function 2014-12-08 21:07:10 -05:00
fib_rules.c net: fix 'ip rule' iif/oif device rename 2014-02-09 19:02:52 -08:00
filter.c net: sock: fix access via invalid file descriptor 2014-12-10 23:34:27 -05:00
flow_dissector.c flow-dissector: Fix alignment issue in __skb_flow_get_ports 2014-10-10 15:33:47 -04:00
flow.c CPU hotplug notifiers registration fixes for 3.15-rc1 2014-04-07 14:55:46 -07:00
gen_estimator.c net: sched: make bstats per cpu and estimator RCU safe 2014-09-30 01:02:26 -04:00
gen_stats.c net_sched: fix unused variables in __gnet_stats_copy_basic_cpu() 2014-10-07 00:10:49 -04:00
iovec.c fold verify_iovec() into copy_msghdr_from_user() 2014-11-19 16:23:49 -05:00
link_watch.c net/core: include linux/types.h instead of asm/types.h 2014-11-18 15:26:32 -05:00
Makefile dmaengine-3.17 2014-10-07 20:39:25 -04:00
neighbour.c neigh: remove dynamic neigh table registration support 2014-11-11 15:23:54 -05:00
net_namespace.c bury struct proc_ns in fs/proc 2014-12-04 14:34:54 -05:00
net-procfs.c rps: selective flow shedding during softnet overflow 2013-05-20 13:48:04 -07:00
net-sysfs.c net-sysfs: expose physical switch id for particular device 2014-12-02 20:01:22 -08:00
net-sysfs.h net: netdev_kobject_init: annotate with __init 2014-01-05 20:27:54 -05:00
net-traces.c
netclassid_cgroup.c cgroup: rename cgroup_subsys->base_cftypes to ->legacy_cftypes 2014-07-15 11:05:09 -04:00
netevent.c
netpoll.c vlan: introduce *vlan_hwaccel_push_inside helpers 2014-11-21 14:20:17 -05:00
netprio_cgroup.c cgroup: rename cgroup_subsys->base_cftypes to ->legacy_cftypes 2014-07-15 11:05:09 -04:00
pktgen.c net: pktgen: Deletion of an unnecessary check before the function call "proc_remove" 2014-11-19 15:20:15 -05:00
ptp_classifier.c net: filter: split 'struct sk_filter' into socket and bpf parts 2014-08-02 15:03:58 -07:00
request_sock.c inet: reduce TLB pressure for listeners 2014-06-25 16:37:24 -07:00
rtnetlink.c net: Disallow providing non zero VLAN ID for NIC drivers FDB add flow 2014-12-16 15:41:19 -05:00
scm.c net: introduce helper macro for_each_cmsghdr 2014-12-10 22:41:55 -05:00
secure_seq.c net: use ktime_get_ns() and ktime_get_real_ns() helpers 2014-08-22 19:57:23 -07:00
skbuff.c net: Reset secmark when scrubbing packet 2014-12-24 00:21:43 -05:00
sock_diag.c net: filter: split 'struct sk_filter' into socket and bpf parts 2014-08-02 15:03:58 -07:00
sock.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2014-12-13 13:33:26 -08:00
stream.c net: replace macros net_random and net_srandom with direct calls to prandom 2014-01-14 15:15:25 -08:00
sysctl_net_core.c net: provide a per host RSS key generic infrastructure 2014-11-16 15:59:11 -05:00
timestamping.c net-timestamp: Make the clone operation stand-alone from phy timestamping 2014-09-05 17:43:45 -07:00
tso.c net: tso: fix unaligned access to crafted TCP header in helper API 2014-10-22 12:52:55 -04:00
utils.c net: Convert LIMIT_NETDEBUG to net_dbg_ratelimited 2014-11-11 14:10:31 -05:00