linux/net/core
Eric Dumazet 3d3be4333f gro: fix different skb headrooms
Packets entering GRO might have different headrooms, even for a given
flow (because of implementation details in drivers, like copybreak).
We cant force drivers to deliver packets with a fixed headroom.

1) fix skb_segment()

skb_segment() makes the false assumption headrooms of fragments are same
than the head. When CHECKSUM_PARTIAL is used, this can give csum_start
errors, and crash later in skb_copy_and_csum_dev()

2) allocate a minimal skb for head of frag_list

skb_gro_receive() uses netdev_alloc_skb(headroom + skb_gro_offset(p)) to
allocate a fresh skb. This adds NET_SKB_PAD to a padding already
provided by netdevice, depending on various things, like copybreak.

Use alloc_skb() to allocate an exact padding, to reduce cache line
needs:
NET_SKB_PAD + NET_IP_ALIGN

bugzilla : https://bugzilla.kernel.org/show_bug.cgi?id=16626

Many thanks to Plamen Petrov, testing many debugging patches !
With help of Jarek Poplawski.

Reported-by: Plamen Petrov <pvp-lsts@fs.uni-ruse.bg>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Jarek Poplawski <jarkao2@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-01 19:17:35 -07:00
..
datagram.c net/core: EXPORT_SYMBOL cleanups 2010-07-12 12:57:55 -07:00
dev_addr_lists.c net: include linux/proc_fs.h in dev_addr_lists.c 2010-04-07 16:46:36 -07:00
dev.c net: Fix a memmove bug in dev_gro_receive() 2010-08-17 17:37:28 -07:00
drop_monitor.c drop_monitor: use genl_register_family_with_ops() 2010-07-26 20:59:42 -07:00
dst.c __dst_free(): put EXPORT_SYMBOLS after the fct 2010-07-20 13:28:03 -07:00
ethtool.c Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 2010-07-07 15:59:38 -07:00
fib_rules.c net: fib_rules: mark arguments to fib_rules_register const and __net_initdata 2010-04-26 16:02:04 +02:00
filter.c net: optimize Berkeley Packet Filter (BPF) processing 2010-06-25 21:33:12 -07:00
flow.c net/core: EXPORT_SYMBOL cleanups 2010-07-12 12:57:55 -07:00
gen_estimator.c pkt_sched: gen_kill_estimator() rcu fixes 2010-06-11 18:37:08 -07:00
gen_stats.c net/core: EXPORT_SYMBOL cleanups 2010-07-12 12:57:55 -07:00
iovec.c net/core: EXPORT_SYMBOL cleanups 2010-07-12 12:57:55 -07:00
kmap_skb.h
link_watch.c net/core: EXPORT_SYMBOL cleanups 2010-07-12 12:57:55 -07:00
Makefile net: support time stamping in phy devices. 2010-07-18 19:15:26 -07:00
neighbour.c net/core: neighbour update Oops 2010-07-14 18:02:16 -07:00
net_namespace.c net: disallow to use net_assign_generic externally 2010-04-27 15:49:02 -07:00
net-sysfs.c sysfs: add attribute to indicate hw address assignment type 2010-07-24 20:49:29 -07:00
net-sysfs.h net: Expose all network devices in a namespaces in sysfs 2010-05-21 09:37:34 -07:00
net-traces.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
netevent.c net/core: EXPORT_SYMBOL cleanups 2010-07-12 12:57:55 -07:00
netpoll.c Revert "net: remove zap_completion_queue" 2010-08-03 00:24:04 -07:00
pktgen.c net: core: don't use own hex_to_bin() method 2010-07-23 12:50:51 -07:00
request_sock.c net: convert BUG_TRAP to generic WARN_ON 2008-07-25 21:43:18 -07:00
rtnetlink.c net/core: EXPORT_SYMBOL cleanups 2010-07-12 12:57:55 -07:00
scm.c net/core: EXPORT_SYMBOL cleanups 2010-07-12 12:57:55 -07:00
skbuff.c gro: fix different skb headrooms 2010-09-01 19:17:35 -07:00
sock.c net: this_cpu_xxx conversions 2010-07-19 15:12:51 -07:00
stream.c net/core: EXPORT_SYMBOL cleanups 2010-07-12 12:57:55 -07:00
sysctl_net_core.c net: Consistent skb timestamping 2010-05-15 23:57:10 -07:00
timestamping.c net: support time stamping in phy devices. 2010-07-18 19:15:26 -07:00
user_dma.c net/core/user_dma.c: Use frag list abstraction interfaces. 2009-06-09 00:19:10 -07:00
utils.c net/core: EXPORT_SYMBOL cleanups 2010-07-12 12:57:55 -07:00