linux.git/net/ipv6, branch v3.14-rc5

gre: add link local route when local addr is any

2014-02-17T19:08:26+00:00

This bug was reported by Steinar H. Gunderson and was introduced by commit
f7cb8886335d ("sit/gre6: don't try to add the same route two times").

root@morgental:~# ip tunnel add foo mode gre remote 1.2.3.4 ttl 64
root@morgental:~# ip link set foo up mtu 1468
root@morgental:~# ip -6 route show dev foo
fe80::/64  proto kernel  metric 256

but after the above commit, no such route shows up.

There is no link local route because dev->dev_addr is 0 (because local ipv4
address is 0), hence no link local address is configured.

In this scenario, the link local address is added manually: 'ip -6 addr add
fe80::1 dev foo' and because prefix is /128, no link local route is added by the
kernel.

Even if the right things to do is to add the link local address with a /64
prefix, we need to restore the previous behavior to avoid breaking userpace.

Reported-by: Steinar H. Gunderson 
Signed-off-by: Nicolas Dichtel 
Signed-off-by: David S. Miller

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

2014-02-13T22:17:02+00:00

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

ipv6: icmp6_send: fix Oops when pinging a not set up IPv6 peer on a sit tunnel

2014-02-10T02:12:40+00:00

The patch 446fab59333dea91e54688f033dd8d788d0486fb ("ipv6: enable anycast addresses
as source addresses in ICMPv6 error messages") causes an Oops when pinging a not
set up IPv6 peer on a sit tunnel.

The problem is that ipv6_anycast_destination() uses unconditionally skb_dst(skb),
which is NULL in this case.

The solution is to use instead the ipv6_chk_acast_addr_src() function.

Here are the steps to reproduce it:
modprobe sit
ip link add sit1 type sit remote 10.16.0.121 local 10.16.0.249
ip l s sit1 up
ip -6 a a dev sit1 2001:1234::123 remote 2001:1234::121
ping6 2001:1234::121

Reported-by: Nicolas Dichtel 
Tested-by: Nicolas Dichtel 
Signed-off-by: Francois-Xavier Le Bail 
Signed-off-by: David S. Miller

netfilter: nf_tables: add reject module for NFPROTO_INET

2014-02-06T08:44:18+00:00

Add a reject module for NFPROTO_INET. It does nothing but dispatch
to the AF-specific modules based on the hook family.

Signed-off-by: Patrick McHardy 
Signed-off-by: Pablo Neira Ayuso

netfilter: nft_reject: split up reject module into IPv4 and IPv6 specifc parts

2014-02-06T08:44:10+00:00

Currently the nft_reject module depends on symbols from ipv6. This is
wrong since no generic module should force IPv6 support to be loaded.
Split up the module into AF-specific and a generic part.

Signed-off-by: Patrick McHardy 
Signed-off-by: Pablo Neira Ayuso

net: Fix memory leak if TPROXY used with TCP early demux

2014-01-28T00:22:11+00:00

I see a memory leak when using a transparent HTTP proxy using TPROXY
together with TCP early demux and Kernel v3.8.13.15 (Ubuntu stable):

unreferenced object 0xffff88008cba4a40 (size 1696):
  comm "softirq", pid 0, jiffies 4294944115 (age 8907.520s)
  hex dump (first 32 bytes):
    0a e0 20 6a 40 04 1b 37 92 be 32 e2 e8 b4 00 00  .. j@..7..2.....
    02 00 07 01 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [] kmem_cache_alloc+0xad/0xb9
    [] sk_prot_alloc+0x29/0xc5
    [] sk_clone_lock+0x14/0x283
    [] inet_csk_clone_lock+0xf/0x7b
    [] netlink_broadcast+0x14/0x16
    [] tcp_create_openreq_child+0x1b/0x4c3
    [] tcp_v4_syn_recv_sock+0x38/0x25d
    [] tcp_check_req+0x25c/0x3d0
    [] tcp_v4_do_rcv+0x287/0x40e
    [] ip_route_input_noref+0x843/0xa55
    [] tcp_v4_rcv+0x4c9/0x725
    [] ip_local_deliver_finish+0xe9/0x154
    [] __netif_receive_skb+0x4b2/0x514
    [] process_backlog+0xee/0x1c5
    [] net_rx_action+0xa7/0x200
    [] add_interrupt_randomness+0x39/0x157

But there are many more, resulting in the machine going OOM after some
days.

From looking at the TPROXY code, and with help from Florian, I see
that the memory leak is introduced in tcp_v4_early_demux():

  void tcp_v4_early_demux(struct sk_buff *skb)
  {
    /* ... */

    iph = ip_hdr(skb);
    th = tcp_hdr(skb);

    if (th->doff < sizeof(struct tcphdr) / 4)
        return;

    sk = __inet_lookup_established(dev_net(skb->dev), &tcp_hashinfo,
                       iph->saddr, th->source,
                       iph->daddr, ntohs(th->dest),
                       skb->skb_iif);
    if (sk) {
        skb->sk = sk;

where the socket is assigned unconditionally to skb->sk, also bumping
the refcnt on it.  This is problematic, because in our case the skb
has already a socket assigned in the TPROXY target.  This then results
in the leak I see.

The very same issue seems to be with IPv6, but haven't tested.

Reviewed-by: Florian Westphal 
Signed-off-by: Holger Eitzenberger 
Signed-off-by: David S. Miller

ipv6: reallocate addrconf router for ipv6 address when lo device up

2014-01-24T23:59:38+00:00

commit 25fb6ca4ed9cad72f14f61629b68dc03c0d9713f
"net IPv6 : Fix broken IPv6 routing table after loopback down-up"
allocates addrconf router for ipv6 address when lo device up.
but commit a881ae1f625c599b460cc8f8a7fcb1c438f699ad
"ipv6:don't call addrconf_dst_alloc again when enable lo" breaks
this behavior.

Since the addrconf router is moved to the garbage list when
lo device down, we should release this router and rellocate
a new one for ipv6 address when lo device up.

This patch solves bug 67951 on bugzilla
https://bugzilla.kernel.org/show_bug.cgi?id=67951

change from v1:
use ip6_rt_put to repleace ip6_del_rt, thanks Hannes!
change code style, suggested by Sergei.

CC: Sabrina Dubroca 
CC: Hannes Frederic Sowa 
Reported-by: Weilong Chen 
Signed-off-by: Weilong Chen 
Signed-off-by: Gao feng 
Acked-by: Hannes Frederic Sowa 
Signed-off-by: David S. Miller

ipv6: enable anycast addresses as source addresses for datagrams

2014-01-23T05:57:05+00:00

This change allows to consider an anycast address valid as source address
when given via an IPV6_PKTINFO or IPV6_2292PKTINFO ancillary data item.
So, when sending a datagram with ancillary data, the unicast and anycast
addresses are handled in the same way.

- Adds ipv6_chk_acast_addr_src() to check if an anycast address is link-local
  on given interface or is global.
- Uses it in ip6_datagram_send_ctl().

Signed-off-by: Francois-Xavier Le Bail 
Acked-by: Hannes Frederic Sowa 
Signed-off-by: David S. Miller

ipv6: protect protocols not handling ipv4 from v4 connection/bind attempts

2014-01-22T00:59:19+00:00

Some ipv6 protocols cannot handle ipv4 addresses, so we must not allow
connecting and binding to them. sendmsg logic does already check msg->name
for this but must trust already connected sockets which could be set up
for connection to ipv4 address family.

Per-socket flag ipv6only is of no use here, as it is under users control
by setsockopt.

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

ipv6: enable anycast addresses as source addresses in ICMPv6 error messages

2014-01-22T00:53:23+00:00

- Uses ipv6_anycast_destination() in icmp6_send().

Suggested-by: Bill Fink 
Signed-off-by: Francois-Xavier Le Bail 
Acked-by: Hannes Frederic Sowa 
Signed-off-by: David S. Miller