diff options
| author | Wei-Chun Chao <weichunc@plumgrid.com> | 2014-06-08 23:48:54 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2014-06-11 00:48:47 -0700 |
| commit | 5882a07c72093dc3a18e2d2b129fb200686bb6ee (patch) | |
| tree | 03835fce7f1315c9a4fc9e4d5d1f972f8ce00596 /net | |
| parent | f6c20c596f41fe6331cee2053b270bf12142b04e (diff) | |
| download | linux-5882a07c72093dc3a18e2d2b129fb200686bb6ee.tar.bz2 | |
net: fix UDP tunnel GSO of frag_list GRO packets
This patch fixes a kernel BUG_ON in skb_segment. It is hit when
testing two VMs on openvswitch with one VM acting as VXLAN gateway.
During VXLAN packet GSO, skb_segment is called with skb->data
pointing to inner TCP payload. skb_segment calls skb_network_protocol
to retrieve the inner protocol. skb_network_protocol actually expects
skb->data to point to MAC and it calls pskb_may_pull with ETH_HLEN.
This ends up pulling in ETH_HLEN data from header tail. As a result,
pskb_trim logic is skipped and BUG_ON is hit later.
Move skb_push in front of skb_network_protocol so that skb->data
lines up properly.
kernel BUG at net/core/skbuff.c:2999!
Call Trace:
[<ffffffff816ac412>] tcp_gso_segment+0x122/0x410
[<ffffffff816bc74c>] inet_gso_segment+0x13c/0x390
[<ffffffff8164b39b>] skb_mac_gso_segment+0x9b/0x170
[<ffffffff816b3658>] skb_udp_tunnel_segment+0xd8/0x390
[<ffffffff816b3c00>] udp4_ufo_fragment+0x120/0x140
[<ffffffff816bc74c>] inet_gso_segment+0x13c/0x390
[<ffffffff8109d742>] ? default_wake_function+0x12/0x20
[<ffffffff8164b39b>] skb_mac_gso_segment+0x9b/0x170
[<ffffffff8164b4d0>] __skb_gso_segment+0x60/0xc0
[<ffffffff8164b6b3>] dev_hard_start_xmit+0x183/0x550
[<ffffffff8166c91e>] sch_direct_xmit+0xfe/0x1d0
[<ffffffff8164bc94>] __dev_queue_xmit+0x214/0x4f0
[<ffffffff8164bf90>] dev_queue_xmit+0x10/0x20
[<ffffffff81687edb>] ip_finish_output+0x66b/0x890
[<ffffffff81688a58>] ip_output+0x58/0x90
[<ffffffff816c628f>] ? fib_table_lookup+0x29f/0x350
[<ffffffff816881c9>] ip_local_out_sk+0x39/0x50
[<ffffffff816cbfad>] iptunnel_xmit+0x10d/0x130
[<ffffffffa0212200>] vxlan_xmit_skb+0x1d0/0x330 [vxlan]
[<ffffffffa02a3919>] vxlan_tnl_send+0x129/0x1a0 [openvswitch]
[<ffffffffa02a2cd6>] ovs_vport_send+0x26/0xa0 [openvswitch]
[<ffffffffa029931e>] do_output+0x2e/0x50 [openvswitch]
Signed-off-by: Wei-Chun Chao <weichunc@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
| -rw-r--r-- | net/core/skbuff.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 8383b2bddeb9..9433047b2453 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -2881,12 +2881,13 @@ struct sk_buff *skb_segment(struct sk_buff *head_skb, int pos; int dummy; + __skb_push(head_skb, doffset); proto = skb_network_protocol(head_skb, &dummy); if (unlikely(!proto)) return ERR_PTR(-EINVAL); csum = !!can_checksum_protocol(features, proto); - __skb_push(head_skb, doffset); + headroom = skb_headroom(head_skb); pos = skb_headlen(head_skb); |