linux-stable/net/core
Vlad Yasevich fcdfe3a7fa net: Correctly set segment mac_len in skb_segment().
When performing segmentation, the mac_len value is copied right
out of the original skb.  However, this value is not always set correctly
(like when the packet is VLAN-tagged) and we'll end up copying a bad
value.

One way to demonstrate this is to configure a VM which tags
packets internally and turn off VLAN acceleration on the forwarding
bridge port.  The packets show up corrupt like this:
16:18:24.985548 52:54:00🆎be:25 > 52:54:00:26:ce:a3, ethertype 802.1Q
(0x8100), length 1518: vlan 100, p 0, ethertype 0x05e0,
        0x0000:  8cdb 1c7c 8cdb 0064 4006 b59d 0a00 6402 ...|...d@.....d.
        0x0010:  0a00 6401 9e0d b441 0a5e 64ec 0330 14fa ..d....A.^d..0..
        0x0020:  29e3 01c9 f871 0000 0101 080a 000a e833)....q.........3
        0x0030:  000f 8c75 6e65 7470 6572 6600 6e65 7470 ...unetperf.netp
        0x0040:  6572 6600 6e65 7470 6572 6600 6e65 7470 erf.netperf.netp
        0x0050:  6572 6600 6e65 7470 6572 6600 6e65 7470 erf.netperf.netp
        0x0060:  6572 6600 6e65 7470 6572 6600 6e65 7470 erf.netperf.netp
        ...

This also leads to awful throughput as GSO packets are dropped and
cause retransmissions.

The solution is to set the mac_len using the values already available
in then new skb.  We've already adjusted all of the header offset, so we
might as well correctly figure out the mac_len using skb_reset_mac_len().
After this change, packets are segmented correctly and performance
is restored.

CC: Eric Dumazet <edumazet@google.com>
Signed-off-by: Vlad Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-31 22:28:39 -07:00
..
datagram.c net: Fix save software checksum complete 2014-06-15 01:00:49 -07:00
dev.c net-gre-gro: Fix a bug that breaks the forwarding path 2014-07-16 14:45:26 -07:00
dev_addr_lists.c net: Add support for device specific address syncing 2014-06-02 10:40:54 -07:00
dev_ioctl.c net_tstamp: Add SIOCGHWTSTAMP ioctl to match SIOCSHWTSTAMP 2013-11-19 19:07:21 +00:00
drop_monitor.c net: drop_monitor: fix the value of maxattr 2013-12-09 21:10:38 -05:00
dst.c ipv4: fix dst race in sk_dst_get() 2014-06-25 17:41:44 -07:00
ethtool.c ethtool: Check that reserved fields of struct ethtool_rxfh are 0 2014-06-03 02:43:16 +01:00
fib_rules.c net: fix 'ip rule' iif/oif device rename 2014-02-09 19:02:52 -08:00
filter.c net: filter: Use kcalloc/kmalloc_array to allocate arrays 2014-06-25 16:40:02 -07:00
flow.c CPU hotplug notifiers registration fixes for 3.15-rc1 2014-04-07 14:55:46 -07:00
flow_dissector.c net: Rename skb->rxhash to skb->hash 2014-03-26 15:58:20 -04:00
gen_estimator.c net_sched: add 64bit rate estimators 2013-06-11 02:51:03 -07:00
gen_stats.c net_sched: add 64bit rate estimators 2013-06-11 02:51:03 -07:00
iovec.c net: sendmsg: fix NULL pointer dereference 2014-07-29 12:20:22 -07:00
link_watch.c arch: Mass conversion of smp_mb__*() 2014-04-18 14:20:48 +02:00
Makefile net: Add a software TSO helper API 2014-05-22 14:57:15 -04:00
neighbour.c neighbour : fix ndm_type type error issue 2014-07-28 17:52:17 -07:00
net-procfs.c
net-sysfs.c Revert "net: return actual error on register_queue_kobjects" 2014-06-19 18:12:15 -07:00
net-sysfs.h net: netdev_kobject_init: annotate with __init 2014-01-05 20:27:54 -05:00
net-traces.c
net_namespace.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2014-05-24 00:32:30 -04:00
netclassid_cgroup.c cgroup: remove css_parent() 2014-05-16 13:22:48 -04:00
netevent.c
netpoll.c netpoll: Use skb_irq_freeable to make zap_completion_queue safe. 2014-04-01 17:53:36 -04:00
netprio_cgroup.c cgroup: remove css_parent() 2014-05-16 13:22:48 -04:00
pktgen.c pktgen: Use seq_puts() where seq_printf() is not needed 2014-05-16 17:30:30 -04:00
ptp_classifier.c net: filter: let unattached filters use sock_fprog_kern 2014-05-23 16:48:05 -04:00
request_sock.c net: remove unnecessary return's 2014-02-13 18:33:38 -05:00
rtnetlink.c rtnetlink: fix userspace API breakage for iproute2 < v3.9.0 2014-06-12 11:07:42 -07:00
scm.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2013-09-07 14:35:32 -07:00
secure_seq.c inetpeer: get rid of ip_id_count 2014-06-02 11:00:41 -07:00
skbuff.c net: Correctly set segment mac_len in skb_segment(). 2014-07-31 22:28:39 -07:00
sock.c net: Split sk_no_check into sk_no_check_{rx,tx} 2014-05-23 16:28:53 -04:00
sock_diag.c net: Move the permission check in sock_diag_put_filterinfo to packet_diag_dump 2014-04-24 13:44:53 -04:00
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 rps: NUMA flow limit allocations 2013-12-19 19:00:07 -05:00
timestamping.c net: ptp: move PTP classifier in its own file 2014-04-01 16:43:18 -04:00
tso.c net: tso: Export symbols for modular build 2014-05-30 15:52:03 -07:00
user_dma.c
utils.c net: avoid dependency of net_get_random_once on nop patching 2014-05-14 00:37:34 -04:00