linux-stable.git/net/ipv6, branch v3.12.12

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

2014-02-06T19:22:21+00:00

[ Upstream commit a452ce345d63ddf92cd101e4196569f8718ad319 ]

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 
Signed-off-by: Greg Kroah-Hartman

net: avoid reference counter overflows on fib_rules in multicast forwarding

2014-02-06T19:22:20+00:00

[ Upstream commit 95f4a45de1a0f172b35451fc52283290adb21f6e ]

Bob Falken reported that after 4G packets, multicast forwarding stopped
working. This was because of a rule reference counter overflow which
freed the rule as soon as the overflow happend.

This patch solves this by adding the FIB_LOOKUP_NOREF flag to
fib_rules_lookup calls. This is safe even from non-rcu locked sections
as in this case the flag only implies not taking a reference to the rule,
which we don't need at all.

Rules only hold references to the namespace, which are guaranteed to be
available during the call of the non-rcu protected function reg_vif_xmit
because of the interface reference which itself holds a reference to
the net namespace.

Fixes: f0ad0860d01e47 ("ipv4: ipmr: support multiple tables")
Fixes: d1db275dd3f6e4 ("ipv6: ip6mr: support multiple tables")
Reported-by: Bob Falken 
Cc: Patrick McHardy 
Cc: Thomas Graf 
Cc: Julian Anastasov 
Cc: Eric Dumazet 
Signed-off-by: Hannes Frederic Sowa 
Acked-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv6: always set the new created dst's from in ip6_rt_copy

2014-01-15T23:31:36+00:00

[ Upstream commit 24f5b855e17df7e355eacd6c4a12cc4d6a6c9ff0 ]

ip6_rt_copy only sets dst.from if ort has flag RTF_ADDRCONF and RTF_DEFAULT.
but the prefix routes which did get installed by hand locally can have an
expiration, and no any flag combination which can ensure a potential from
does never expire, so we should always set the new created dst's from.

This also fixes the new created dst is always expired since the ort, which
is created by RA, maybe has RTF_EXPIRES and RTF_ADDRCONF, but no RTF_DEFAULT.

Suggested-by: Hannes Frederic Sowa 
CC: Gao feng 
Signed-off-by: Li RongQing 
Acked-by: Hannes Frederic Sowa 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv6: fix illegal mac_header comparison on 32bit

2014-01-15T23:31:35+00:00

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

inet: fix NULL pointer Oops in fib(6)_rule_suppress

2014-01-15T23:31:34+00:00

[ Upstream commit 673498b8ed4c4d4b7221c5309d891c5eac2b7528 ]

This changes ensures that the routing entry investigated by the suppress
function actually does point to a device struct before following that pointer,
fixing a possible kernel oops situation when verifying the interface group
associated with a routing table entry.

According to Daniel Golle, this Oops can be triggered by a user process trying
to establish an outgoing IPv6 connection while having no real IPv6 connectivity
set up (only autoassigned link-local addresses).

Fixes: 6ef94cfafba15 ("fib_rules: add route suppression based on ifgroup")

Reported-by: Daniel Golle 
Tested-by: Daniel Golle 
Signed-off-by: Stefan Tomanek 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv6: don't count addrconf generated routes against gc limit

2014-01-15T23:31:34+00:00

[ Upstream commit a3300ef4bbb1f1e33ff0400e1e6cf7733d988f4f ]

Brett Ciphery reported that new ipv6 addresses failed to get installed
because the addrconf generated dsts where counted against the dst gc
limit. We don't need to count those routes like we currently don't count
administratively added routes.

Because the max_addresses check enforces a limit on unbounded address
generation first in case someone plays with router advertisments, we
are still safe here.

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

IPv6: Fixed support for blackhole and prohibit routes

2014-01-15T23:31:32+00:00

[ Upstream commit 7150aede5dd241539686e17d9592f5ebd28a2cda ]

The behaviour of blackhole and prohibit routes has been corrected by setting
the input and output pointers of the dst variable appropriately. For
blackhole routes, they are set to dst_discard and to ip6_pkt_discard and
ip6_pkt_discard_out respectively for prohibit routes.

ipv6: ip6_pkt_prohibit(_out) should not depend on
CONFIG_IPV6_MULTIPLE_TABLES

We need ip6_pkt_prohibit(_out) available without
CONFIG_IPV6_MULTIPLE_TABLES

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

xfrm: Fix null pointer dereference when decoding sessions

2013-12-08T15:29:15+00:00

[ Upstream commit 84502b5ef9849a9694673b15c31bd3ac693010ae ]

On some codepaths the skb does not have a dst entry
when xfrm_decode_session() is called. So check for
a valid skb_dst() before dereferencing the device
interface index. We use 0 as the device index if
there is no valid skb_dst(), or at reverse decoding
we use skb_iif as device interface index.

Bug was introduced with git commit bafd4bd4dc
("xfrm: Decode sessions with output interface.").

Reported-by: Meelis Roos 
Tested-by: Meelis Roos 
Signed-off-by: Steffen Klassert 
Signed-off-by: Greg Kroah-Hartman

ipv6: fix possible seqlock deadlock in ip6_finish_output2

2013-12-08T15:29:15+00:00

[ Upstream commit 7f88c6b23afbd31545c676dea77ba9593a1a14bf ]

IPv6 stats are 64 bits and thus are protected with a seqlock. By not
disabling bottom-half we could deadlock here if we don't disable bh and
a softirq reentrantly updates the same mib.

Cc: Eric Dumazet 
Signed-off-by: Hannes Frederic Sowa 
Acked-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

gro: Clean up tcpX_gro_receive checksum verification

2013-12-08T15:29:14+00:00

[ Upstream commit b8ee93ba80b5a0b6c3c06b65c34dd1276f16c047 ]

This patch simplifies the checksum verification in tcpX_gro_receive
by reusing the CHECKSUM_COMPLETE code for CHECKSUM_NONE.  All it
does for CHECKSUM_NONE is compute the partial checksum and then
treat it as if it came from the hardware (CHECKSUM_COMPLETE).

Signed-off-by: Herbert Xu 

Cheers,
Acked-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman