linux/net/core
Daniel Borkmann 8065694e65 bpf: fix checksum for vlan push/pop helper
When having skbs on ingress with CHECKSUM_COMPLETE, tc BPF programs don't
push rcsum of mac header back in and after BPF run back pull out again as
opposed to some other subsystems (ovs, for example).

For cases like q-in-q, meaning when a vlan tag for offloading is already
present and we're about to push another one, then skb_vlan_push() pushes the
inner one into the skb, increasing mac header and skb_postpush_rcsum()'ing
the 4 bytes vlan header diff. Likewise, for the reverse operation in
skb_vlan_pop() for the case where vlan header needs to be pulled out of the
skb, we're decreasing the mac header and skb_postpull_rcsum()'ing the 4 bytes
rcsum of the vlan header that was removed.

However mangling the rcsum here will lead to hw csum failure for BPF case,
since we're pulling or pushing data that was not part of the current rcsum.
Changing tc BPF programs in general to push/pull rcsum around BPF_PROG_RUN()
is also not really an option since current behaviour is ABI by now, but apart
from that would also mean to do quite a bit of useless work in the sense that
usually 12 bytes need to be rcsum pushed/pulled also when we don't need to
touch this vlan related corner case. One way to fix it would be to push the
necessary rcsum fixup down into vlan helpers that are (mostly) slow-path
anyway.

Fixes: 4e10df9a60 ("bpf: introduce bpf_skb_vlan_push/pop() helpers")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-08 13:11:43 -07:00
..
datagram.c udp: enable MSG_PEEK at non-zero offset 2016-04-05 16:29:37 -04:00
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 Merge branch 'salted-string-hash' 2016-07-28 12:26:31 -07:00
devlink.c devlink: add hardware messages tracing facility 2016-07-12 14:20:18 -07:00
drop_monitor.c net: tracepoint napi:napi_poll add work and budget 2016-07-09 18:05:02 -04:00
dst_cache.c net: dst_cache_per_cpu_dst_set() can be static 2016-03-18 17:45:08 -04:00
dst.c net: add dst_cache to ovs vxlan lwtunnel 2016-02-16 20:21:48 -05:00
ethtool.c sctp: Add GSO support 2016-06-03 19:37:21 -04:00
fib_rules.c fib_rules: Added NLM_F_EXCL support to fib_nl_newrule 2016-06-30 08:23:19 -04:00
filter.c bpf: fix checksum for vlan push/pop helper 2016-08-08 13:11:43 -07:00
flow_dissector.c packet: Use symmetric hash for PACKET_FANOUT_HASH. 2016-07-01 16:07:50 -04:00
flow.c flowcache: Avoid OOM condition under preasure 2016-03-17 10:28:42 +01:00
gen_estimator.c net: sched: do not acquire qdisc spinlock in qdisc/class stats dump 2016-06-07 16:37:14 -07:00
gen_stats.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-06-10 11:52:24 -07:00
hwbm.c net: hwbm: Fix unbalanced spinlock in error case 2016-05-25 12:35:09 -07:00
link_watch.c dev: introduce dev_get_iflink() 2015-04-02 14:04:59 -04:00
lwtunnel.c lwtunnel: autoload of lwt modules 2016-02-21 22:00:28 -05:00
Makefile net: add a hardware buffer management helper API 2016-03-14 12:19:46 -04:00
neighbour.c net: neigh: disallow transition to NUD_STALE if lladdr is unchanged in neigh_update() 2016-07-26 14:25:20 -07:00
net_namespace.c netns: make nsid_lock per net 2015-05-17 23:41:11 -04:00
net-procfs.c net: remove NETDEV_TX_LOCKED support 2016-04-26 15:53:05 -04:00
net-sysfs.c net: introduce NETDEV_CHANGE_TX_QUEUE_LEN 2016-07-01 05:32:17 -04:00
net-sysfs.h net: netdev_kobject_init: annotate with __init 2014-01-05 20:27:54 -05:00
net-traces.c net: IPv6 fib lookup tracepoint 2015-11-22 11:54:10 -05:00
netclassid_cgroup.c core: remove unneded headers for net cgroup controllers. 2016-02-17 15:31:27 -05:00
netevent.c netevent: remove automatic variable in register_netevent_notifier() 2015-05-31 00:03:21 -07:00
netpoll.c net: tracepoint napi:napi_poll add work and budget 2016-07-09 18:05:02 -04:00
netprio_cgroup.c core: remove unneded headers for net cgroup controllers. 2016-02-17 15:31:27 -05:00
pktgen.c net: pktgen: support injecting packets for qdisc testing 2016-07-04 16:07:34 -07:00
ptp_classifier.c ptp: Change ptp_class to a proper bitmask 2015-11-03 11:08:22 -05:00
request_sock.c tcp: restore fastopen operations 2015-10-05 03:19:06 -07:00
rtnetlink.c rtnl: protect do_setlink from IFLA_XDP_ATTACHED 2016-07-20 22:07:23 -07:00
scm.c unix: correctly track in-flight fds in sending process user_struct 2016-02-08 10:30:42 -05:00
secure_seq.c net: remove a sparse error in secure_dccpv6_sequence_number() 2015-05-25 22:55:37 -04:00
skbuff.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-07-06 10:35:22 -07:00
sock_diag.c sock_diag: align nlattr properly when needed 2016-04-26 12:00:48 -04:00
sock_reuseport.c soreuseport: fix NULL ptr dereference SO_REUSEPORT after bind 2016-01-19 14:44:23 -05:00
sock.c dccp: limit sk_filter trim to payload 2016-07-13 11:53:41 -07:00
stream.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-12-03 21:09:12 -05:00
sysctl_net_core.c bpf: add generic constant blinding for use in jits 2016-05-16 13:49:32 -04:00
timestamping.c net: skb_defer_rx_timestamp should check for phydev before setting up classify 2015-07-09 14:17:15 -07:00
tso.c net: tso: add support for IPv6 2015-10-26 22:24:22 -07:00
utils.c net: the space is required before the open parenthesis '(' 2016-06-29 05:15:14 -04:00