Commit graph

4595 commits

Author SHA1 Message Date
Mark Brown
da9a92f0cd Merge branch 'linux-linaro-lsk-v4.4' into linux-linaro-lsk-v4.4-android 2016-07-29 21:38:37 +01:00
Martin KaFai Lau
9c458a8668 ipv6: Fix mem leak in rt6i_pcpu
[ Upstream commit 903ce4abdf374e3365d93bcb3df56c62008835ba ]

It was first reported and reproduced by Petr (thanks!) in
https://bugzilla.kernel.org/show_bug.cgi?id=119581

free_percpu(rt->rt6i_pcpu) used to always happen in ip6_dst_destroy().

However, after fixing a deadlock bug in
commit 9c7370a166 ("ipv6: Fix a potential deadlock when creating pcpu rt"),
free_percpu() is not called before setting non_pcpu_rt->rt6i_pcpu to NULL.

It is worth to note that rt6i_pcpu is protected by table->tb6_lock.

kmemleak somehow did not report it.  We nailed it down by
observing the pcpu entries in /proc/vmallocinfo (first suggested
by Hannes, thanks!).

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Fixes: 9c7370a166 ("ipv6: Fix a potential deadlock when creating pcpu rt")
Reported-by: Petr Novopashenniy <pety@rusnet.ru>
Tested-by: Petr Novopashenniy <pety@rusnet.ru>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Petr Novopashenniy <pety@rusnet.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-07-27 09:47:31 -07:00
Alex Shi
aa6b4960f4 Merge branch 'linux-linaro-lsk-v4.4' into linux-linaro-lsk-v4.4-android 2016-07-17 12:18:15 +08:00
Tom Goff
d05916086f ipmr/ip6mr: Initialize the last assert time of mfc entries.
[ Upstream commit 70a0dec45174c976c64b4c8c1d0898581f759948 ]

This fixes wrong-interface signaling on 32-bit platforms for entries
created when jiffies > 2^31 + MFC_ASSERT_THRESH.

Signed-off-by: Tom Goff <thomas.goff@ll.mit.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-07-11 09:31:11 -07:00
Simon Horman
9d6814d7ae sit: correct IP protocol used in ipip6_err
[ Upstream commit d5d8760b78d0cfafe292f965f599988138b06a70 ]

Since 32b8a8e59c ("sit: add IPv4 over IPv4 support")
ipip6_err() may be called for packets whose IP protocol is
IPPROTO_IPIP as well as those whose IP protocol is IPPROTO_IPV6.

In the case of IPPROTO_IPIP packets the correct protocol value is not
passed to ipv4_update_pmtu() or ipv4_redirect().

This patch resolves this problem by using the IP protocol of the packet
rather than a hard-coded value. This appears to be consistent
with the usage of the protocol of a packet by icmp_socket_deliver()
the caller of ipip6_err().

I was able to exercise the redirect case by using a setup where an ICMP
redirect was received for the destination of the encapsulated packet.
However, it appears that although incorrect the protocol field is not used
in this case and thus no problem manifests.  On inspection it does not
appear that a problem will manifest in the fragmentation needed/update pmtu
case either.

In short I believe this is a cosmetic fix. None the less, the use of
IPPROTO_IPV6 seems wrong and confusing.

Reviewed-by: Dinan Gunawardena <dinan.gunawardena@netronome.com>
Signed-off-by: Simon Horman <simon.horman@netronome.com>
Acked-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-07-11 09:31:11 -07:00
Alex Shi
fb8ebda5d9 Merge branch 'linux-linaro-lsk-v4.4' into linux-linaro-lsk-v4.4-android 2016-06-27 12:18:04 +08:00
Florian Westphal
e917563612 netfilter: x_tables: introduce and use xt_copy_counters_from_user
commit d7591f0c41ce3e67600a982bab6989ef0f07b3ce upstream.

The three variants use same copy&pasted code, condense this into a
helper and use that.

Make sure info.name is 0-terminated.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-24 10:18:24 -07:00
Florian Westphal
d69f93d059 netfilter: x_tables: do compat validation via translate_table
commit 09d9686047dbbe1cf4faa558d3ecc4aae2046054 upstream.

This looks like refactoring, but its also a bug fix.

Problem is that the compat path (32bit iptables, 64bit kernel) lacks a few
sanity tests that are done in the normal path.

For example, we do not check for underflows and the base chain policies.

While its possible to also add such checks to the compat path, its more
copy&pastry, for instance we cannot reuse check_underflow() helper as
e->target_offset differs in the compat case.

Other problem is that it makes auditing for validation errors harder; two
places need to be checked and kept in sync.

At a high level 32 bit compat works like this:
1- initial pass over blob:
   validate match/entry offsets, bounds checking
   lookup all matches and targets
   do bookkeeping wrt. size delta of 32/64bit structures
   assign match/target.u.kernel pointer (points at kernel
   implementation, needed to access ->compatsize etc.)

2- allocate memory according to the total bookkeeping size to
   contain the translated ruleset

3- second pass over original blob:
   for each entry, copy the 32bit representation to the newly allocated
   memory.  This also does any special match translations (e.g.
   adjust 32bit to 64bit longs, etc).

4- check if ruleset is free of loops (chase all jumps)

5-first pass over translated blob:
   call the checkentry function of all matches and targets.

The alternative implemented by this patch is to drop steps 3&4 from the
compat process, the translation is changed into an intermediate step
rather than a full 1:1 translate_table replacement.

In the 2nd pass (step #3), change the 64bit ruleset back to a kernel
representation, i.e. put() the kernel pointer and restore ->u.user.name .

This gets us a 64bit ruleset that is in the format generated by a 64bit
iptables userspace -- we can then use translate_table() to get the
'native' sanity checks.

This has two drawbacks:

1. we re-validate all the match and target entry structure sizes even
though compat translation is supposed to never generate bogus offsets.
2. we put and then re-lookup each match and target.

THe upside is that we get all sanity tests and ruleset validations
provided by the normal path and can remove some duplicated compat code.

iptables-restore time of autogenerated ruleset with 300k chains of form
-A CHAIN0001 -m limit --limit 1/s -j CHAIN0002
-A CHAIN0002 -m limit --limit 1/s -j CHAIN0003

shows no noticeable differences in restore times:
old:   0m30.796s
new:   0m31.521s
64bit: 0m25.674s

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-24 10:18:24 -07:00
Florian Westphal
3a69c0f048 netfilter: x_tables: xt_compat_match_from_user doesn't need a retval
commit 0188346f21e6546498c2a0f84888797ad4063fc5 upstream.

Always returned 0.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-24 10:18:23 -07:00
Florian Westphal
0fab6d3d18 netfilter: ip6_tables: simplify translate_compat_table args
commit 329a0807124f12fe1c8032f95d8a8eb47047fb0e upstream.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-24 10:18:23 -07:00
Florian Westphal
8a86562154 netfilter: x_tables: check for bogus target offset
commit ce683e5f9d045e5d67d1312a42b359cb2ab2a13c upstream.

We're currently asserting that targetoff + targetsize <= nextoff.

Extend it to also check that targetoff is >= sizeof(xt_entry).
Since this is generic code, add an argument pointing to the start of the
match/target, we can then derive the base structure size from the delta.

We also need the e->elems pointer in a followup change to validate matches.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-24 10:18:23 -07:00
Florian Westphal
2985d199e7 netfilter: x_tables: add compat version of xt_check_entry_offsets
commit fc1221b3a163d1386d1052184202d5dc50d302d1 upstream.

32bit rulesets have different layout and alignment requirements, so once
more integrity checks get added to xt_check_entry_offsets it will reject
well-formed 32bit rulesets.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-24 10:18:23 -07:00
Florian Westphal
6bc803b795 netfilter: x_tables: kill check_entry helper
commit aa412ba225dd3bc36d404c28cdc3d674850d80d0 upstream.

Once we add more sanity testing to xt_check_entry_offsets it
becomes relvant if we're expecting a 32bit 'config_compat' blob
or a normal one.

Since we already have a lot of similar-named functions (check_entry,
compat_check_entry, find_and_check_entry, etc.) and the current
incarnation is short just fold its contents into the callers.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-24 10:18:22 -07:00
Florian Westphal
cfdca13028 netfilter: x_tables: add and use xt_check_entry_offsets
commit 7d35812c3214afa5b37a675113555259cfd67b98 upstream.

Currently arp/ip and ip6tables each implement a short helper to check that
the target offset is large enough to hold one xt_entry_target struct and
that t->u.target_size fits within the current rule.

Unfortunately these checks are not sufficient.

To avoid adding new tests to all of ip/ip6/arptables move the current
checks into a helper, then extend this helper in followup patches.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-24 10:18:22 -07:00
Florian Westphal
611d408a53 netfilter: x_tables: validate targets of jumps
commit 36472341017529e2b12573093cc0f68719300997 upstream.

When we see a jump also check that the offset gets us to beginning of
a rule (an ipt_entry).

The extra overhead is negible, even with absurd cases.

300k custom rules, 300k jumps to 'next' user chain:
[ plus one jump from INPUT to first userchain ]:

Before:
real    0m24.874s
user    0m7.532s
sys     0m16.076s

After:
real    0m27.464s
user    0m7.436s
sys     0m18.840s

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-24 10:18:22 -07:00
Florian Westphal
d6f7cd1b21 netfilter: x_tables: don't move to non-existent next rule
commit f24e230d257af1ad7476c6e81a8dc3127a74204e upstream.

Ben Hawkes says:

 In the mark_source_chains function (net/ipv4/netfilter/ip_tables.c) it
 is possible for a user-supplied ipt_entry structure to have a large
 next_offset field. This field is not bounds checked prior to writing a
 counter value at the supplied offset.

Base chains enforce absolute verdict.

User defined chains are supposed to end with an unconditional return,
xtables userspace adds them automatically.

But if such return is missing we will move to non-existent next rule.

Reported-by: Ben Hawkes <hawkes@google.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-24 10:18:22 -07:00
Florian Westphal
5ebdccd768 netfilter: x_tables: fix unconditional helper
commit 54d83fc74aa9ec72794373cb47432c5f7fb1a309 upstream.

Ben Hawkes says:

 In the mark_source_chains function (net/ipv4/netfilter/ip_tables.c) it
 is possible for a user-supplied ipt_entry structure to have a large
 next_offset field. This field is not bounds checked prior to writing a
 counter value at the supplied offset.

Problem is that mark_source_chains should not have been called --
the rule doesn't have a next entry, so its supposed to return
an absolute verdict of either ACCEPT or DROP.

However, the function conditional() doesn't work as the name implies.
It only checks that the rule is using wildcard address matching.

However, an unconditional rule must also not be using any matches
(no -m args).

The underflow validator only checked the addresses, therefore
passing the 'unconditional absolute verdict' test, while
mark_source_chains also tested for presence of matches, and thus
proceeeded to the next (not-existent) rule.

Unify this so that all the callers have same idea of 'unconditional rule'.

Reported-by: Ben Hawkes <hawkes@google.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-24 10:18:22 -07:00
Florian Westphal
868fe2536f netfilter: x_tables: make sure e->next_offset covers remaining blob size
commit 6e94e0cfb0887e4013b3b930fa6ab1fe6bb6ba91 upstream.

Otherwise this function may read data beyond the ruleset blob.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-24 10:18:22 -07:00
Florian Westphal
59ff9f9b38 netfilter: x_tables: validate e->target_offset early
commit bdf533de6968e9686df777dc178486f600c6e617 upstream.

We should check that e->target_offset is sane before
mark_source_chains gets called since it will fetch the target entry
for loop detection.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-24 10:18:22 -07:00
Jakub Sitnicki
4d82f395bb ipv6: Skip XFRM lookup if dst_entry in socket cache is valid
[ Upstream commit 00bc0ef5880dc7b82f9c320dead4afaad48e47be ]

At present we perform an xfrm_lookup() for each UDPv6 message we
send. The lookup involves querying the flow cache (flow_cache_lookup)
and, in case of a cache miss, creating an XFRM bundle.

If we miss the flow cache, we can end up creating a new bundle and
deriving the path MTU (xfrm_init_pmtu) from on an already transformed
dst_entry, which we pass from the socket cache (sk->sk_dst_cache) down
to xfrm_lookup(). This can happen only if we're caching the dst_entry
in the socket, that is when we're using a connected UDP socket.

To put it another way, the path MTU shrinks each time we miss the flow
cache, which later on leads to incorrectly fragmented payload. It can
be observed with ESPv6 in transport mode:

  1) Set up a transformation and lower the MTU to trigger fragmentation
    # ip xfrm policy add dir out src ::1 dst ::1 \
      tmpl src ::1 dst ::1 proto esp spi 1
    # ip xfrm state add src ::1 dst ::1 \
      proto esp spi 1 enc 'aes' 0x0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b
    # ip link set dev lo mtu 1500

  2) Monitor the packet flow and set up an UDP sink
    # tcpdump -ni lo -ttt &
    # socat udp6-listen:12345,fork /dev/null &

  3) Send a datagram that needs fragmentation with a connected socket
    # perl -e 'print "@" x 1470 | socat - udp6:[::1]:12345
    2016/06/07 18:52:52 socat[724] E read(3, 0x555bb3d5ba00, 8192): Protocol error
    00:00:00.000000 IP6 ::1 > ::1: frag (0|1448) ESP(spi=0x00000001,seq=0x2), length 1448
    00:00:00.000014 IP6 ::1 > ::1: frag (1448|32)
    00:00:00.000050 IP6 ::1 > ::1: ESP(spi=0x00000001,seq=0x3), length 1272
    (^ ICMPv6 Parameter Problem)
    00:00:00.000022 IP6 ::1 > ::1: ESP(spi=0x00000001,seq=0x5), length 136

  4) Compare it to a non-connected socket
    # perl -e 'print "@" x 1500' | socat - udp6-sendto:[::1]:12345
    00:00:40.535488 IP6 ::1 > ::1: frag (0|1448) ESP(spi=0x00000001,seq=0x6), length 1448
    00:00:00.000010 IP6 ::1 > ::1: frag (1448|64)

What happens in step (3) is:

  1) when connecting the socket in __ip6_datagram_connect(), we
     perform an XFRM lookup, miss the flow cache, create an XFRM
     bundle, and cache the destination,

  2) afterwards, when sending the datagram, we perform an XFRM lookup,
     again, miss the flow cache (due to mismatch of flowi6_iif and
     flowi6_oif, which is an issue of its own), and recreate an XFRM
     bundle based on the cached (and already transformed) destination.

To prevent the recreation of an XFRM bundle, avoid an XFRM lookup
altogether whenever we already have a destination entry cached in the
socket. This prevents the path MTU shrinkage and brings us on par with
UDPv4.

The fix also benefits connected PINGv6 sockets, another user of
ip6_sk_dst_lookup_flow(), who also suffer messages being transformed
twice.

Joint work with Hannes Frederic Sowa.

Reported-by: Jan Tluka <jtluka@redhat.com>
Signed-off-by: Jakub Sitnicki <jkbs@redhat.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-24 10:18:17 -07:00
Yuchung Cheng
f946ceab11 tcp: record TLP and ER timer stats in v6 stats
[ Upstream commit ce3cf4ec0305919fc69a972f6c2b2efd35d36abc ]

The v6 tcp stats scan do not provide TLP and ER timer information
correctly like the v4 version . This patch fixes that.

Fixes: 6ba8a3b19e ("tcp: Tail loss probe (TLP)")
Fixes: eed530b6c6 ("tcp: early retransmit")
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-24 10:18:17 -07:00
Hannes Frederic Sowa
ab1f253ddc udp: prevent skbs lingering in tunnel socket queues
[ Upstream commit e5aed006be918af163eb397e45aa5ea6cefd5e01 ]

In case we find a socket with encapsulation enabled we should call
the encap_recv function even if just a udp header without payload is
available. The callbacks are responsible for correctly verifying and
dropping the packets.

Also, in case the header validation fails for geneve and vxlan we
shouldn't put the skb back into the socket queue, no one will pick
them up there.  Instead we can simply discard them in the respective
encap_recv functions.

Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-24 10:18:16 -07:00
Alex Shi
cf5ba83bb2 Merge branch 'lsk-v4.4-android' of git://android.git.linaro.org/kernel/linaro-android into linux-linaro-lsk-v4.4-android 2016-06-02 17:59:02 +08:00
Alex Shi
023861726f Merge branch 'linux-linaro-lsk-v4.4' into linux-linaro-lsk-v4.4-android 2016-05-20 12:16:40 +08:00
Dmitry Shmidt
3094efd84c Revert "net: socket ioctl to reset connections matching local address"
Use SOCK_DESTROY from now instead of SIOCKILLADDR

This reverts commit 38f0ec724f.

Change-Id: I2dcd833b66c88a48de8978dce9d72ab78f9af549
2016-05-19 12:32:41 +05:30
Paolo Abeni
1c76c5d5ff net/route: enforce hoplimit max value
[ Upstream commit 626abd59e51d4d8c6367e03aae252a8aa759ac78 ]

Currently, when creating or updating a route, no check is performed
in both ipv4 and ipv6 code to the hoplimit value.

The caller can i.e. set hoplimit to 256, and when such route will
 be used, packets will be sent with hoplimit/ttl equal to 0.

This commit adds checks for the RTAX_HOPLIMIT value, in both ipv4
ipv6 route code, substituting any value greater than 255 with 255.

This is consistent with what is currently done for ADVMSS and MTU
in the ipv4 code.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-18 17:06:43 -07:00
Daniel Borkmann
79fdabe870 net: use skb_postpush_rcsum instead of own implementations
[ Upstream commit 6b83d28a55a891a9d70fc61ccb1c138e47dcbe74 ]

Replace individual implementations with the recently introduced
skb_postpush_rcsum() helper.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Tom Herbert <tom@herbertland.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-18 17:06:36 -07:00
Alex Shi
bab1564182 Merge branch 'linux-linaro-lsk-v4.4' into linux-linaro-lsk-v4.4-android
Conflicts:
	d_canonical_path in include/linux/dcache.h
2016-04-21 14:08:44 +08:00
Jakub Sitnicki
5598928f39 ipv6: Count in extension headers in skb->network_header
[ Upstream commit 3ba3458fb9c050718b95275a3310b74415e767e2 ]

When sending a UDPv6 message longer than MTU, account for the length
of fragmentable IPv6 extension headers in skb->network_header offset.
Same as we do in alloc_new_skb path in __ip6_append_data().

This ensures that later on __ip6_make_skb() will make space in
headroom for fragmentable extension headers:

	/* move skb->data to ip header from ext header */
	if (skb->data < skb_network_header(skb))
		__skb_pull(skb, skb_network_offset(skb));

Prevents a splat due to skb_under_panic:

skbuff: skb_under_panic: text:ffffffff8143397b len:2126 put:14 \
head:ffff880005bacf50 data:ffff880005bacf4a tail:0x48 end:0xc0 dev:lo
------------[ cut here ]------------
kernel BUG at net/core/skbuff.c:104!
invalid opcode: 0000 [#1] KASAN
CPU: 0 PID: 160 Comm: reproducer Not tainted 4.6.0-rc2 #65
[...]
Call Trace:
 [<ffffffff813eb7b9>] skb_push+0x79/0x80
 [<ffffffff8143397b>] eth_header+0x2b/0x100
 [<ffffffff8141e0d0>] neigh_resolve_output+0x210/0x310
 [<ffffffff814eab77>] ip6_finish_output2+0x4a7/0x7c0
 [<ffffffff814efe3a>] ip6_output+0x16a/0x280
 [<ffffffff815440c1>] ip6_local_out+0xb1/0xf0
 [<ffffffff814f1115>] ip6_send_skb+0x45/0xd0
 [<ffffffff81518836>] udp_v6_send_skb+0x246/0x5d0
 [<ffffffff8151985e>] udpv6_sendmsg+0xa6e/0x1090
[...]

Reported-by: Ji Jianwen <jiji@redhat.com>
Signed-off-by: Jakub Sitnicki <jkbs@redhat.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-20 15:42:07 +09:00
Thadeu Lima de Souza Cascardo
4f4de9ab66 ip6_tunnel: set rtnl_link_ops before calling register_netdevice
[ Upstream commit b6ee376cb0b7fb4e7e07d6cd248bd40436fb9ba6 ]

When creating an ip6tnl tunnel with ip tunnel, rtnl_link_ops is not set
before ip6_tnl_create2 is called. When register_netdevice is called, there
is no linkinfo attribute in the NEWLINK message because of that.

Setting rtnl_link_ops before calling register_netdevice fixes that.

Fixes: 0b11245722 ("ip6tnl: add support of link creation via rtnl")
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@redhat.com>
Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-20 15:42:06 +09:00
Eric Dumazet
26dd42ebff ipv6: udp: fix UDP_MIB_IGNOREDMULTI updates
[ Upstream commit 2d4212261fdf13e29728ddb5ea9d60c342cc92b5 ]

IPv6 counters updates use a different macro than IPv4.

Fixes: 36cbb2452c ("udp: Increment UDP_MIB_IGNOREDMULTI for arriving unmatched multicasts")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Rick Jones <rick.jones2@hp.com>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-20 15:42:05 +09:00
Bill Sommerfeld
8a2226c17e udp6: fix UDP/IPv6 encap resubmit path
[ Upstream commit 59dca1d8a6725a121dae6c452de0b2611d5865dc ]

IPv4 interprets a negative return value from a protocol handler as a
request to redispatch to a new protocol.  In contrast, IPv6 interprets a
negative value as an error, and interprets a positive value as a request
for redispatch.

UDP for IPv6 was unaware of this difference.  Change __udp6_lib_rcv() to
return a positive value for redispatch.  Note that the socket's
encap_rcv hook still needs to return a negative value to request
dispatch, and in the case of IPv6 packets, adjust IP6CB(skb)->nhoff to
identify the byte containing the next protocol.

Signed-off-by: Bill Sommerfeld <wsommerfeld@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-20 15:42:00 +09:00
Florian Westphal
b80398d91c ipv6: re-enable fragment header matching in ipv6_find_hdr
[ Upstream commit 5d150a985520bbe3cb2aa1ceef24a7e32f20c15f ]

When ipv6_find_hdr is used to find a fragment header
(caller specifies target NEXTHDR_FRAGMENT) we erronously return
-ENOENT for all fragments with nonzero offset.

Before commit 9195bb8e38, when target was specified, we did not
enter the exthdr walk loop as nexthdr == target so this used to work.

Now we do (so we can skip empty route headers). When we then stumble upon
a frag with nonzero frag_off we must return -ENOENT ("header not found")
only if the caller did not specifically request NEXTHDR_FRAGMENT.

This allows nfables exthdr expression to match ipv6 fragments, e.g. via

nft add rule ip6 filter input frag frag-off gt 0

Fixes: 9195bb8e38 ("ipv6: improve ipv6_find_hdr() to skip empty routing headers")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-20 15:41:59 +09:00
Benjamin Poirier
d9bbdcd83d mld, igmp: Fix reserved tailroom calculation
[ Upstream commit 1837b2e2bcd23137766555a63867e649c0b637f0 ]

The current reserved_tailroom calculation fails to take hlen and tlen into
account.

skb:
[__hlen__|__data____________|__tlen___|__extra__]
^                                               ^
head                                            skb_end_offset

In this representation, hlen + data + tlen is the size passed to alloc_skb.
"extra" is the extra space made available in __alloc_skb because of
rounding up by kmalloc. We can reorder the representation like so:

[__hlen__|__data____________|__extra__|__tlen___]
^                                               ^
head                                            skb_end_offset

The maximum space available for ip headers and payload without
fragmentation is min(mtu, data + extra). Therefore,
reserved_tailroom
= data + extra + tlen - min(mtu, data + extra)
= skb_end_offset - hlen - min(mtu, skb_end_offset - hlen - tlen)
= skb_tailroom - min(mtu, skb_tailroom - tlen) ; after skb_reserve(hlen)

Compare the second line to the current expression:
reserved_tailroom = skb_end_offset - min(mtu, skb_end_offset)
and we can see that hlen and tlen are not taken into account.

The min() in the third line can be expanded into:
if mtu < skb_tailroom - tlen:
	reserved_tailroom = skb_tailroom - mtu
else:
	reserved_tailroom = tlen

Depending on hlen, tlen, mtu and the number of multicast address records,
the current code may output skbs that have less tailroom than
dev->needed_tailroom or it may output more skbs than needed because not all
space available is used.

Fixes: 4c672e4b ("ipv6: mld: fix add_grhead skb_over_panic for devs with large MTUs")
Signed-off-by: Benjamin Poirier <bpoirier@suse.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-20 15:41:58 +09:00
Bernie Harris
207485dc4f tunnel: Clear IPCB(skb)->opt before dst_link_failure called
[ Upstream commit 5146d1f151122e868e594c7b45115d64825aee5f ]

IPCB may contain data from previous layers (in the observed case the
qdisc layer). In the observed scenario, the data was misinterpreted as
ip header options, which later caused the ihl to be set to an invalid
value (<5). This resulted in an infinite loop in the mips implementation
of ip_fast_csum.

This patch clears IPCB(skb)->opt before dst_link_failure can be called for
various types of tunnels. This change only applies to encapsulated ipv4
packets.

The code introduced in 11c21a30 which clears all of IPCB has been removed
to be consistent with these changes, and instead the opt field is cleared
unconditionally in ip_tunnel_xmit. The change in ip_tunnel_xmit applies to
SIT, GRE, and IPIP tunnels.

The relevant vti, l2tp, and pptp functions already contain similar code for
clearing the IPCB.

Signed-off-by: Bernie Harris <bernie.harris@alliedtelesis.co.nz>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-20 15:41:56 +09:00
Brian Norris
4f27b251f2 ANDROID: net: fix 'const' warnings
See the following build log splats. The sock_i_uid() helper doesn't
quite treat the parameter as 'const' (it acquires a member lock), but
this cast is the same approach taken by other callers in this file, so I
don't feel too bad about the fix.

  CC      net/ipv4/inet_connection_sock.o
  CC      net/ipv6/inet6_connection_sock.o
net/ipv6/inet6_connection_sock.c: In function ‘inet6_csk_route_req’:
net/ipv6/inet6_connection_sock.c:89:2: warning: passing argument 1 of ‘sock_i_uid’ discards ‘const’ qualifier from pointer target type [enabled by default]
In file included from include/linux/tcp.h:22:0,
                 from include/linux/ipv6.h:73,
                 from net/ipv6/inet6_connection_sock.c:18:
include/net/sock.h:1689:8: note: expected ‘struct sock *’ but argument is of type ‘const struct sock *’
net/ipv4/inet_connection_sock.c: In function ‘inet_csk_route_req’:
net/ipv4/inet_connection_sock.c:423:7: warning: passing argument 1 of ‘sock_i_uid’ discards ‘const’ qualifier from pointer target type [enabled by default]
In file included from include/net/inet_sock.h:27:0,
                 from include/net/inet_connection_sock.h:23,
                 from net/ipv4/inet_connection_sock.c:19:
include/net/sock.h:1689:8: note: expected ‘struct sock *’ but argument is of type ‘const struct sock *’
net/ipv4/inet_connection_sock.c: In function ‘inet_csk_route_child_sock’:
net/ipv4/inet_connection_sock.c:460:7: warning: passing argument 1 of ‘sock_i_uid’ discards ‘const’ qualifier from pointer target type [enabled by default]
In file included from include/net/inet_sock.h:27:0,
                 from include/net/inet_connection_sock.h:23,
                 from net/ipv4/inet_connection_sock.c:19:
include/net/sock.h:1689:8: note: expected ‘struct sock *’ but argument is of type ‘const struct sock *’

Change-Id: I5c156fc1a81f90323717bffd93c31d205b85620c
Signed-off-by: Brian Norris <briannorris@google.com>
2016-04-07 16:49:54 +05:30
Lorenzo Colitti
69f0e89f55 net: diag: Support destroying TCP sockets.
This implements SOCK_DESTROY for TCP sockets. It causes all
blocking calls on the socket to fail fast with ECONNABORTED and
causes a protocol close of the socket. It informs the other end
of the connection by sending a RST, i.e., initiating a TCP ABORT
as per RFC 793. ECONNABORTED was chosen for consistency with
FreeBSD.

[cherry-pick of net-next c1e64e298b8cad309091b95d8436a0255c84f54a]

Change-Id: I728a01ef03f2ccfb9016a3f3051ef00975980e49
Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-07 16:49:53 +05:30
Alex Shi
fa6e6c7406 Merge branch 'linux-linaro-lsk-v4.4' into linux-linaro-lsk-v4.4-android
Conflicts solution:
	keep 'KBUILD_CFLAGS += -fno-pic'
	in arch/arm64/Makefile
2016-03-14 15:32:21 +08:00
Anton Protopopov
b7c2e2acc6 rtnl: RTM_GETNETCONF: fix wrong return value
[ Upstream commit a97eb33ff225f34a8124774b3373fd244f0e83ce ]

An error response from a RTM_GETNETCONF request can return the positive
error value EINVAL in the struct nlmsgerr that can mislead userspace.

Signed-off-by: Anton Protopopov <a.s.protopopov@gmail.com>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-03 15:07:07 -08:00
Eric Dumazet
9653359eb6 tcp/dccp: fix another race at listener dismantle
[ Upstream commit 7716682cc58e305e22207d5bb315f26af6b1e243 ]

Ilya reported following lockdep splat:

kernel: =========================
kernel: [ BUG: held lock freed! ]
kernel: 4.5.0-rc1-ceph-00026-g5e0a311 #1 Not tainted
kernel: -------------------------
kernel: swapper/5/0 is freeing memory
ffff880035c9d200-ffff880035c9dbff, with a lock still held there!
kernel: (&(&queue->rskq_lock)->rlock){+.-...}, at:
[<ffffffff816f6a88>] inet_csk_reqsk_queue_add+0x28/0xa0
kernel: 4 locks held by swapper/5/0:
kernel: #0:  (rcu_read_lock){......}, at: [<ffffffff8169ef6b>]
netif_receive_skb_internal+0x4b/0x1f0
kernel: #1:  (rcu_read_lock){......}, at: [<ffffffff816e977f>]
ip_local_deliver_finish+0x3f/0x380
kernel: #2:  (slock-AF_INET){+.-...}, at: [<ffffffff81685ffb>]
sk_clone_lock+0x19b/0x440
kernel: #3:  (&(&queue->rskq_lock)->rlock){+.-...}, at:
[<ffffffff816f6a88>] inet_csk_reqsk_queue_add+0x28/0xa0

To properly fix this issue, inet_csk_reqsk_queue_add() needs
to return to its callers if the child as been queued
into accept queue.

We also need to make sure listener is still there before
calling sk->sk_data_ready(), by holding a reference on it,
since the reference carried by the child can disappear as
soon as the child is put on accept queue.

Reported-by: Ilya Dryomov <idryomov@gmail.com>
Fixes: ebb516af60 ("tcp/dccp: fix race at listener dismantle phase")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-03 15:07:07 -08:00
Eric Dumazet
2679161c77 tcp: do not drop syn_recv on all icmp reports
[ Upstream commit 9cf7490360bf2c46a16b7525f899e4970c5fc144 ]

Petr Novopashenniy reported that ICMP redirects on SYN_RECV sockets
were leading to RST.

This is of course incorrect.

A specific list of ICMP messages should be able to drop a SYN_RECV.

For instance, a REDIRECT on SYN_RECV shall be ignored, as we do
not hold a dst per SYN_RECV pseudo request.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=111751
Fixes: 079096f103 ("tcp/dccp: install syn_recv requests into ehash table")
Reported-by: Petr Novopashenniy <pety@rusnet.ru>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-03 15:07:05 -08:00
Eric Dumazet
4c890233fd ipv6: fix a lockdep splat
[ Upstream commit 44c3d0c1c0a880354e9de5d94175742e2c7c9683 ]

Silence lockdep false positive about rcu_dereference() being
used in the wrong context.

First one should use rcu_dereference_protected() as we own the spinlock.

Second one should be a normal assignation, as no barrier is needed.

Fixes: 18367681a1 ("ipv6 flowlabel: Convert np->ipv6_fl_list to RCU.")
Reported-by: Dave Jones <davej@codemonkey.org.uk>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-03 15:07:05 -08:00
subashab@codeaurora.org
cdbc66828d ipv6: addrconf: Fix recursive spin lock call
[ Upstream commit 16186a82de1fdd868255448274e64ae2616e2640 ]

A rcu stall with the following backtrace was seen on a system with
forwarding, optimistic_dad and use_optimistic set. To reproduce,
set these flags and allow ipv6 autoconf.

This occurs because the device write_lock is acquired while already
holding the read_lock. Back trace below -

INFO: rcu_preempt self-detected stall on CPU { 1}  (t=2100 jiffies
 g=3992 c=3991 q=4471)
<6> Task dump for CPU 1:
<2> kworker/1:0     R  running task    12168    15   2 0x00000002
<2> Workqueue: ipv6_addrconf addrconf_dad_work
<6> Call trace:
<2> [<ffffffc000084da8>] el1_irq+0x68/0xdc
<2> [<ffffffc000cc4e0c>] _raw_write_lock_bh+0x20/0x30
<2> [<ffffffc000bc5dd8>] __ipv6_dev_ac_inc+0x64/0x1b4
<2> [<ffffffc000bcbd2c>] addrconf_join_anycast+0x9c/0xc4
<2> [<ffffffc000bcf9f0>] __ipv6_ifa_notify+0x160/0x29c
<2> [<ffffffc000bcfb7c>] ipv6_ifa_notify+0x50/0x70
<2> [<ffffffc000bd035c>] addrconf_dad_work+0x314/0x334
<2> [<ffffffc0000b64c8>] process_one_work+0x244/0x3fc
<2> [<ffffffc0000b7324>] worker_thread+0x2f8/0x418
<2> [<ffffffc0000bb40c>] kthread+0xe0/0xec

v2: do addrconf_dad_kick inside read lock and then acquire write
lock for ipv6_ifa_notify as suggested by Eric

Fixes: 7fd2561e4e ("net: ipv6: Add a sysctl to make optimistic
addresses useful candidates")

Cc: Eric Dumazet <edumazet@google.com>
Cc: Erik Kline <ek@google.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-03 15:07:05 -08:00
Paolo Abeni
e1c4e14bf1 ipv6/udp: use sticky pktinfo egress ifindex on connect()
[ Upstream commit 1cdda91871470f15e79375991bd2eddc6e86ddb1 ]

Currently, the egress interface index specified via IPV6_PKTINFO
is ignored by __ip6_datagram_connect(), so that RFC 3542 section 6.7
can be subverted when the user space application calls connect()
before sendmsg().
Fix it by initializing properly flowi6_oif in connect() before
performing the route lookup.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-03 15:07:05 -08:00
Paolo Abeni
e8e729ccd2 ipv6: enforce flowi6_oif usage in ip6_dst_lookup_tail()
[ Upstream commit 6f21c96a78b835259546d8f3fb4edff0f651d478 ]

The current implementation of ip6_dst_lookup_tail basically
ignore the egress ifindex match: if the saddr is set,
ip6_route_output() purposefully ignores flowi6_oif, due
to the commit d46a9d678e ("net: ipv6: Dont add RT6_LOOKUP_F_IFACE
flag if saddr set"), if the saddr is 'any' the first route lookup
in ip6_dst_lookup_tail fails, but upon failure a second lookup will
be performed with saddr set, thus ignoring the ifindex constraint.

This commit adds an output route lookup function variant, which
allows the caller to specify lookup flags, and modify
ip6_dst_lookup_tail() to enforce the ifindex match on the second
lookup via said helper.

ip6_route_output() becames now a static inline function build on
top of ip6_route_output_flags(); as a side effect, out-of-tree
modules need now a GPL license to access the output route lookup
functionality.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-03 15:07:05 -08:00
Amit Pundir
02bbd06e48 Merge branch 'android-4.4' of https://android.googlesource.com/kernel/common
* android-4.4: (475 commits)
  android: base-cfg: Add CONFIG_IP_MULTICAST
  android: recommended.cfg: enable taskstats
  ANDROID: android: base-cfg: disable CONFIG_SYSVIPC
  android: configs: base: enable configfs gadget functions
  android: add CONFIG_DEBUG_RODATA to recommended config
  android: configs: remove CONFIG_BATTERY_ANDROID=y
  android: configs: base: enable IPV6
  android: configs: Enable SELinux and its dependencies.
  android: base-cfg: disable ALARM_DEV
  android: base-cfg: turn off /dev/mem and /dev/kmem
  android: base-cfg: enable ARMV8_DEPRECATED and subfeatures
  android: base-cfg: enforce the needed XFRM_MODE_TUNNEL (for VPN)
  android: base-cfg: disable LOGGER
  android: base-cfg: enable DM_VERITY (used for secureboot)
  android: configs: add systrace support to recommended configs
  android: configs: update 3.10 options
  android: configs: Add CONFIG_NETFILTER_XT_TARGET_IDLETIMER
  android: configs: add IPV6 ROUTE INFO
  android: configs: add TIMER_STATS back, helps with sysrq t.
  android: configs: Add HIDRAW to recommended set
  ...
2016-02-18 00:20:12 +05:30
Amit Pundir
04f86f74f2 net: ipv6: fix virtual tunneling build
IPv6 PMTUD has been updated to support UID-based routing.

Pass INVALID_UID as the socket UID to ip6_update_pmtu(),
otherwise we run into following build error:
----------------
  CC      net/ipv6/ip6_vti.o
net/ipv6/ip6_vti.c: In function ‘vti6_err’:
net/ipv6/ip6_vti.c:559:3: error: too few arguments to function ‘ip6_update_pmtu’
In file included from include/net/ip_tunnels.h:19:0,
                 from net/ipv6/ip6_vti.c:44:
include/net/ip6_route.h:110:6: note: declared here
make[2]: *** [net/ipv6/ip6_vti.o] Error 1
----------------

Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
2016-02-16 13:51:45 -08:00
Lorenzo Colitti
fd2cf795f3 net: core: Support UID-based routing.
This contains the following commits:

1. cc2f522 net: core: Add a UID range to fib rules.
2. d7ed2bd net: core: Use the socket UID in routing lookups.
3. 2f9306a net: core: Add a RTA_UID attribute to routes.
    This is so that userspace can do per-UID route lookups.
4. 8e46efb net: ipv6: Use the UID in IPv6 PMTUD
    IPv4 PMTUD already does this because ipv4_sk_update_pmtu
    uses __build_flow_key, which includes the UID.

Bug: 15413527
Change-Id: Iae3d4ca3979d252b6cec989bdc1a6875f811f03a
Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
2016-02-16 13:51:37 -08:00
Amit Pundir
d005e957b7 net: ipv6: fix build failure if IPV6_ROUTE_INFO config is enabled
Pass correct arguments to rt6_get_route_info() function, otherwise
we run into following Kernel build failure:
----------
  CC      net/ipv6/route.o
net/ipv6/route.c: In function ‘rt6_route_rcv’:
net/ipv6/route.c:746:27: error: ‘net’ undeclared (first use in this function)
net/ipv6/route.c:746:27: note: each undeclared identifier is reported only once for each function it appears in
make[2]: *** [net/ipv6/route.o] Error 1
make[1]: *** [net/ipv6] Error 2
make: *** [net] Error 2
----------

Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
2016-02-16 13:51:36 -08:00
Lorenzo Colitti
6dd69fdc00 net: ipv6: autoconf routes into per-device tables
Currently, IPv6 router discovery always puts routes into
RT6_TABLE_MAIN. This causes problems for connection managers
that want to support multiple simultaneous network connections
and want control over which one is used by default (e.g., wifi
and wired).

To work around this connection managers typically take the routes
they prefer and copy them to static routes with low metrics in
the main table. This puts the burden on the connection manager
to watch netlink to see if the routes have changed, delete the
routes when their lifetime expires, etc.

Instead, this patch adds a per-interface sysctl to have the
kernel put autoconf routes into different tables. This allows
each interface to have its own autoconf table, and choosing the
default interface (or using different interfaces at the same
time for different types of traffic) can be done using
appropriate ip rules.

The sysctl behaves as follows:

- = 0: default. Put routes into RT6_TABLE_MAIN as before.
- > 0: manual. Put routes into the specified table.
- < 0: automatic. Add the absolute value of the sysctl to the
       device's ifindex, and use that table.

The automatic mode is most useful in conjunction with
net.ipv6.conf.default.accept_ra_rt_table. A connection manager
or distribution could set it to, say, -100 on boot, and
thereafter just use IP rules.

Change-Id: I82d16e3737d9cdfa6489e649e247894d0d60cbb1
Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
2016-02-16 13:51:36 -08:00