linux-stable.git/net/ipv6, branch v3.10.38

ipv6: some ipv6 statistic counters failed to disable bh

2014-04-14T13:42:18+00:00

[ Upstream commit 43a43b6040165f7b40b5b489fe61a4cb7f8c4980 ]

After commit c15b1ccadb323ea ("ipv6: move DAD and addrconf_verify
processing to workqueue") some counters are now updated in process context
and thus need to disable bh before doing so, otherwise deadlocks can
happen on 32-bit archs. Fabio Estevam noticed this while while mounting
a NFS volume on an ARM board.

As a compensation for missing this I looked after the other *_STATS_BH
and found three other calls which need updating:

1) icmp6_send: ip6_fragment -> icmpv6_send -> icmp6_send (error handling)
2) ip6_push_pending_frames: rawv6_sendmsg -> rawv6_push_pending_frames -> ...
   (only in case of icmp protocol with raw sockets in error handling)
3) ping6_v6_sendmsg (error handling)

Fixes: c15b1ccadb323ea ("ipv6: move DAD and addrconf_verify processing to workqueue")
Reported-by: Fabio Estevam 
Tested-by: Fabio Estevam 
Cc: Eric Dumazet 
Signed-off-by: Hannes Frederic Sowa 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ip6mr: fix mfc notification flags

2014-04-14T13:42:17+00:00

[ Upstream commit f518338b16038beeb73e155e60d0f70beb9379f4 ]

Commit 812e44dd1829 ("ip6mr: advertise new mfc entries via rtnl") reuses the
function ip6mr_fill_mroute() to notify mfc events.
But this function was used only for dump and thus was always setting the
flag NLM_F_MULTI, which is wrong in case of a single notification.

Libraries like libnl will wait forever for NLMSG_DONE.

CC: Thomas Graf 
Signed-off-by: Nicolas Dichtel 
Acked-by: Thomas Graf 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv6: ip6_append_data_mtu do not handle the mtu of the second fragment properly

2014-04-14T13:42:17+00:00

[ Upstream commit e367c2d03dba4c9bcafad24688fadb79dd95b218 ]

In ip6_append_data_mtu(), when the xfrm mode is not tunnel(such as
transport),the ipsec header need to be added in the first fragment, so the mtu
will decrease to reserve space for it, then the second fragment come, the mtu
should be turn back, as the commit 0c1833797a5a6ec23ea9261d979aa18078720b74
said.  however, in the commit a493e60ac4bbe2e977e7129d6d8cbb0dd236be, it use
*mtu = min(*mtu, ...) to change the mtu, which lead to the new mtu is alway
equal with the first fragment's. and cannot turn back.

when I test through  ping6 -c1 -s5000 $ip (mtu=1280):
...frag (0|1232) ESP(spi=0x00002000,seq=0xb), length 1232
...frag (1232|1216)
...frag (2448|1216)
...frag (3664|1216)
...frag (4880|164)

which should be:
...frag (0|1232) ESP(spi=0x00001000,seq=0x1), length 1232
...frag (1232|1232)
...frag (2464|1232)
...frag (3696|1232)
...frag (4928|116)

so delete the min() when change back the mtu.

Signed-off-by: Xin Long 
Fixes: 75a493e60ac4bb ("ipv6: ip6_append_data_mtu did not care about pmtudisc and frag_size")
Acked-by: Hannes Frederic Sowa 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv6: Avoid unnecessary temporary addresses being generated

2014-04-14T13:42:16+00:00

[ Upstream commit ecab67015ef6e3f3635551dcc9971cf363cc1cd5 ]

tmp_prefered_lft is an offset to ifp->tstamp, not now. Therefore
age needs to be added to the condition.

Age calculation in ipv6_create_tempaddr is different from the one
in addrconf_verify and doesn't consider ADDRCONF_TIMER_FUZZ_MINUS.
This can cause age in ipv6_create_tempaddr to be less than the one
in addrconf_verify and therefore unnecessary temporary address to
be generated.
Use age calculation as in addrconf_modify to avoid this.

Signed-off-by: Heiner Kallweit 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv6: don't set DST_NOCOUNT for remotely added routes

2014-04-14T13:42:16+00:00

[ Upstream commit c88507fbad8055297c1d1e21e599f46960cbee39 ]

DST_NOCOUNT should only be used if an authorized user adds routes
locally. In case of routes which are added on behalf of router
advertisments this flag must not get used as it allows an unlimited
number of routes getting added remotely.

Signed-off-by: Sabrina Dubroca 
Acked-by: Hannes Frederic Sowa 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv6: Fix exthdrs offload registration.

2014-04-14T13:42:16+00:00

[ Upstream commit d2d273ffabd315eecefce21a4391d44b6e156b73 ]

Without this fix, ipv6_exthdrs_offload_init doesn't register IPPROTO_DSTOPTS
offload, but returns 0 (as the IPPROTO_ROUTING registration actually succeeds).

This then causes the ipv6_gso_segment to drop IPv6 packets with IPPROTO_DSTOPTS
header.

The issue detected and the fix verified by running MS HCK Offload LSO test on
top of QEMU Windows guests, as this test sends IPv6 packets with
IPPROTO_DSTOPTS.

Signed-off-by: Anton Nayshtut 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv6: ipv6_find_hdr restore prev functionality

2014-03-24T04:38:10+00:00

[ Upstream commit accfe0e356327da5bd53da8852b93fc22de9b5fc ]

The commit 9195bb8e381d81d5a315f911904cdf0cfcc919b8 ("ipv6: improve
ipv6_find_hdr() to skip empty routing headers") broke ipv6_find_hdr().

When a target is specified like IPPROTO_ICMPV6 ipv6_find_hdr()
returns -ENOENT when it's found, not the header as expected.

A part of IPVS is broken and possible also nft_exthdr_eval().
When target is -1 which it is most cases, it works.

This patch exits the do while loop if the specific header is found
so the nexthdr could be returned as expected.

Reported-by: Art -kwaak- van Breemen 
Signed-off-by: Hans Schillstrom 
CC:Ansis Atteka 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv6: reuse ip6_frag_id from ip6_ufo_append_data

2014-03-24T04:38:10+00:00

[ Upstream commit 916e4cf46d0204806c062c8c6c4d1f633852c5b6 ]

Currently we generate a new fragmentation id on UFO segmentation. It
is pretty hairy to identify the correct net namespace and dst there.
Especially tunnels use IFF_XMIT_DST_RELEASE and thus have no skb_dst
available at all.

This causes unreliable or very predictable ipv6 fragmentation id
generation while segmentation.

Luckily we already have pregenerated the ip6_frag_id in
ip6_ufo_append_data and can use it here.

Signed-off-by: Hannes Frederic Sowa 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: ip, ipv6: handle gso skbs in forwarding path

2014-03-07T05:30:05+00:00

commit fe6cc55f3a9a053482a76f5a6b2257cee51b4663 upstream.

Marcelo Ricardo Leitner reported problems when the forwarding link path
has a lower mtu than the incoming one if the inbound interface supports GRO.

Given:
Host  R1  R2

Host sends tcp stream which is routed via R1 and R2.  R1 performs GRO.

In this case, the kernel will fail to send ICMP fragmentation needed
messages (or pkt too big for ipv6), as GSO packets currently bypass dstmtu
checks in forward path. Instead, Linux tries to send out packets exceeding
the mtu.

When locking route MTU on Host (i.e., no ipv4 DF bit set), R1 does
not fragment the packets when forwarding, and again tries to send out
packets exceeding R1-R2 link mtu.

This alters the forwarding dstmtu checks to take the individual gso
segment lengths into account.

For ipv6, we send out pkt too big error for gso if the individual
segments are too big.

For ipv4, we either send icmp fragmentation needed, or, if the DF bit
is not set, perform software segmentation and let the output path
create fragments when the packet is leaving the machine.
It is not 100% correct as the error message will contain the headers of
the GRO skb instead of the original/segmented one, but it seems to
work fine in my (limited) tests.

Eric Dumazet suggested to simply shrink mss via ->gso_size to avoid
sofware segmentation.

However it turns out that skb_segment() assumes skb nr_frags is related
to mss size so we would BUG there.  I don't want to mess with it considering
Herbert and Eric disagree on what the correct behavior should be.

Hannes Frederic Sowa notes that when we would shrink gso_size
skb_segment would then also need to deal with the case where
SKB_MAX_FRAGS would be exceeded.

This uses sofware segmentation in the forward path when we hit ipv4
non-DF packets and the outgoing link mtu is too small.  Its not perfect,
but given the lack of bug reports wrt. GRO fwd being broken this is a
rare case anyway.  Also its not like this could not be improved later
once the dust settles.

Acked-by: Herbert Xu 
Reported-by: Marcelo Ricardo Leitner 
Signed-off-by: Florian Westphal 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ip6tnl: fix double free of fb_tnl_dev on exit

2014-02-06T19:08:17+00:00

[ No relevant upstream commit. ]

This problem was fixed upstream by commit 1e9f3d6f1c40 ("ip6tnl: fix use after
free of fb_tnl_dev").
The upstream patch depends on upstream commit 0bd8762824e7 ("ip6tnl: add x-netns
support"), which was not backported into 3.10 branch.

First, explain the problem: when the ip6_tunnel module is unloaded,
ip6_tunnel_cleanup() is called.
rmmod ip6_tunnel
=> ip6_tunnel_cleanup()
  => rtnl_link_unregister()
    => __rtnl_kill_links()
      => for_each_netdev(net, dev) {
        if (dev->rtnl_link_ops == ops)
        	ops->dellink(dev, &list_kill);
        }
At this point, the FB device is deleted (and all ip6tnl tunnels).
  => unregister_pernet_device()
    => unregister_pernet_operations()
      => ops_exit_list()
        => ip6_tnl_exit_net()
          => ip6_tnl_destroy_tunnels()
            => t = rtnl_dereference(ip6n->tnls_wc[0]);
               unregister_netdevice_queue(t->dev, &list);
We delete the FB device a second time here!

The previous fix removes these lines, which fix this double free. But the patch
introduces a memory leak when a netns is destroyed, because the FB device is
never deleted. By adding an rtnl ops which delete all ip6tnl device excepting
the FB device, we can keep this exlicit removal in ip6_tnl_destroy_tunnels().

CC: Steven Rostedt 
CC: Willem de Bruijn 
Signed-off-by: Nicolas Dichtel 
Reported-by: Steven Rostedt 
Tested-by: Steven Rostedt  (and our entire MRG team)
Tested-by: "Luis Claudio R. Goncalves" 
Tested-by: John Kacur 
Signed-off-by: Greg Kroah-Hartman