Move the whole rt6_need_strict as static inline into ip6_route.h,
so that it can be reused
Signed-off-by: NWang Yufen <wangyufen@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If an IPv6 host route with metrics exists, an attempt to add a
new route for the same target with different metrics fails but
rewrites the metrics anyway:

12sp0:~ # ip route add fec0::1 dev eth0 rto_min 1000
12sp0:~ # ip -6 route show
fe80::/64 dev eth0  proto kernel  metric 256
fec0::1 dev eth0  metric 1024  rto_min lock 1s
12sp0:~ # ip route add fec0::1 dev eth0 rto_min 1500
RTNETLINK answers: File exists
12sp0:~ # ip -6 route show
fe80::/64 dev eth0  proto kernel  metric 256
fec0::1 dev eth0  metric 1024  rto_min lock 1.5s

This is caused by all IPv6 host routes using the metrics in
their inetpeer (or the shared default). This also holds for the
new route created in ip6_route_add() which shares the metrics
with the already existing route and thus ip6_route_add()
rewrites the metrics even if the new route ends up not being
used at all.

Another problem is that old metrics in inetpeer can reappear
unexpectedly for a new route, e.g.

12sp0:~ # ip route add fec0::1 dev eth0 rto_min 1000
12sp0:~ # ip route del fec0::1
12sp0:~ # ip route add fec0::1 dev eth0
12sp0:~ # ip route change fec0::1 dev eth0 hoplimit 10
12sp0:~ # ip -6 route show
fe80::/64 dev eth0  proto kernel  metric 256
fec0::1 dev eth0  metric 1024  hoplimit 10 rto_min lock 1s

Resolve the first problem by moving the setting of metrics down
into fib6_add_rt2node() to the point we are sure we are
inserting the new route into the tree. Second problem is
addressed by introducing new flag DST_METRICS_FORCE_OVERWRITE
which is set for a new host route in ip6_route_add() and makes
ipv6_cow_metrics() always overwrite the metrics in inetpeer
(even if they are not "new"); it is reset after that.

v5: use a flag in _metrics member rather than one in flags

v4: fix a typo making a condition always true (thanks to Hannes
Frederic Sowa)

v3: rewritten based on David Miller's idea to move setting the
metrics (and allocation in non-host case) down to the point we
already know the route is to be inserted. Also rebased to
net-next as it is quite late in the cycle.
Signed-off-by: NMichal Kubecek <mkubecek@suse.cz>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: NSabrina Dubroca <sd@queasysnail.net>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

since the prune parameter for fib6_clean_all always is 0, remove it.
Signed-off-by: NLi RongQing <roy.qing.li@gmail.com>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Running 'make namespacecheck' shows:
  net/ipv6/route.o
    ipv6_route_table_template
    rt6_bind_peer
  net/ipv6/icmp.o
    icmpv6_route_lookup
    ipv6_icmp_table_template

This addresses some of those warnings by:
 * make icmpv6_route_lookup static
 * move inline's out of ip6_route.h since only used into route.c
 * move rt6_bind_peer into route.c
Signed-off-by: NStephen Hemminger <stephen@networkplumber.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: NHannes Frederic Sowa <hannes@stressinduktion.org>
CC: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: NLi RongQing <roy.qing.li@gmail.com>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

RFC 4191 states in 3.5:

   When a host avoids using any non-reachable router X and instead sends
   a data packet to another router Y, and the host would have used
   router X if router X were reachable, then the host SHOULD probe each
   such router X's reachability by sending a single Neighbor
   Solicitation to that router's address.  A host MUST NOT probe a
   router's reachability in the absence of useful traffic that the host
   would have sent to the router if it were reachable.  In any case,
   these probes MUST be rate-limited to no more than one per minute per
   router.

Currently, when the neighbour corresponding to a router falls into
NUD_FAILED, it's never considered again. Introduce a new rt6_nud_state
value, RT6_NUD_FAIL_PROBE, which suggests the route should not be used but
should be probed with a single NS. The probe is ratelimited by the existing
code. To better distinguish meanings of the failure values, rename
RT6_NUD_FAIL_SOFT to RT6_NUD_FAIL_DO_RR.
Signed-off-by: NJiri Benc <jbenc@redhat.com>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: NBrett Ciphery <brett.ciphery@windriver.com>
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: NKamala R <kamala@aristanetworks.com>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As the rfc 4191 said, the Router Preference and Lifetime values in a
::/0 Route Information Option should override the preference and lifetime
values in the Router Advertisement header. But when the kernel deals with
a ::/0 Route Information Option, the rt6_get_route_info() always return
NULL, that means that overriding will not happen, because those default
routers were added without flag RTF_ROUTEINFO in rt6_add_dflt_router().

In order to deal with that condition, we should call rt6_get_dflt_router
when the prefix length is 0.
Signed-off-by: NDuan Jiong <duanj.fnst@cn.fujitsu.com>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now rt6_alloc_cow() is only called by ip6_pol_route() when
rt->rt6i_flags doesn't contain both RTF_NONEXTHOP and RTF_GATEWAY,
and rt->rt6i_flags hasn't been changed in ip6_rt_copy().
So there is no neccessary to judge whether rt->rt6i_flags contains
RTF_GATEWAY or not.
Signed-off-by: NDuan Jiong <duanj.fnst@cn.fujitsu.com>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

After reading the function rt6_check_neigh(), we can
know that the RT6_NUD_FAIL_SOFT can be returned only
when the IS_ENABLE(CONFIG_IPV6_ROUTER_PREF) is false.
so in function find_match(), there is no need to execute
the statement !IS_ENABLED(CONFIG_IPV6_ROUTER_PREF).
Signed-off-by: NDuan Jiong <duanj.fnst@cn.fujitsu.com>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

On receiving a packet too big icmp error we check if our current cached
dst_entry in the socket is still valid. This validation check did not
care about the expiration of the (cached) route.

The error path I traced down:
The socket receives a packet too big mtu notification. It still has a
valid dst_entry and thus issues the ip6_rt_pmtu_update on this dst_entry,
setting RTF_EXPIRE and updates the dst.expiration value (which could
fail because of not up-to-date expiration values, see previous patch).

In some seldom cases we race with a) the ip6_fib gc or b) another routing
lookup which would result in a recreation of the cached rt6_info from its
parent non-cached rt6_info. While copying the rt6_info we reinitialize the
metrics store by copying it over from the parent thus invalidating the
just installed pmtu update (both dsts use the same key to the inetpeer
storage). The dst_entry with the just invalidated metrics data would
just get its RTF_EXPIRES flag cleared and would continue to stay valid
for the socket.

We should have not issued the pmtu update on the already expired dst_entry
in the first placed. By checking the expiration on the dst entry and
doing a relookup in case it is out of date we close the race because
we would install a new rt6_info into the fib before we issue the pmtu
update, thus closing this race.

Not reliably updating the dst.expire value was fixed by the patch "ipv6:
reset dst.expires value when clearing expire flag".
Reported-by: NSteinar H. Gunderson <sgunderson@bigfoot.com>
Reported-by: NValentijn Sessink <valentyn@blub.net>
Cc: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Reviewed-by: NEric Dumazet <edumazet@google.com>
Tested-by: NValentijn Sessink <valentyn@blub.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Routes need to be probed asynchronous otherwise the call stack gets
exhausted when the kernel attemps to deliver another skb inline, like
e.g. xt_TEE does, and we probe at the same time.

We update neigh->updated still at once, otherwise we would send to
many probes.

Cc: Julian Anastasov <ja@ssi.bg>
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Make sure rt6i_gateway contains nexthop information in
all routes returned from lookup or when routes are directly
attached to skb for generated ICMP packets.

The effect of this patch should be a faster version of
rt6_nexthop() and the consideration of local addresses as
nexthop.
Signed-off-by: NJulian Anastasov <ja@ssi.bg>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

setting fl6.flowi6_flags as zero after memset is redundant, Remove it.
Signed-off-by: NLi RongQing <roy.qing.li@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Dumping routes on a system with lots rt6_infos in the fibs causes up to
11-order allocations in seq_file (which fail). While we could switch
there to vmalloc we could just implement the streaming interface for
/proc/net/ipv6_route. This patch switches /proc/net/ipv6_route from
single_open_net to seq_open_net.

loff_t *pos tracks dst entries.

Also kill never used struct rt6_proc_arg and now unused function
fib6_clean_all_ro.

Cc: Ben Greear <greearb@candelatech.com>
Cc: Patrick McHardy <kaber@trash.net>
Cc: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

RFC 4861 says that the IP source address of the Redirect is the
same as the current first-hop router for the specified ICMP
Destination Address, so the gateway should be taken into
consideration when we find the route for redirect.

There was once a check in commit
a6279458 ("NDISC: Search over
all possible rules on receipt of redirect.") and the check
went away in commit b94f1c09
("ipv6: Use icmpv6_notify() to propagate redirect, instead of
rt6_redirect()").

The bug is only "exploitable" on layer-2 because the source
address of the redirect is checked to be a valid link-local
address but it makes spoofing a lot easier in the same L2
domain nonetheless.

Thanks very much for Hannes's help.
Signed-off-by: NDuan Jiong <duanj.fnst@cn.fujitsu.com>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It will be used by vxlan, and may not be inlined.

Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NCong Wang <amwang@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

rfc 4861 says the Redirected Header option is optional, so
the kernel should not drop the Redirect Message that has no
Redirected Header option. In this patch, the function
ip6_redirect_no_header() is introduced to deal with that
condition.
Signed-off-by: NDuan Jiong <duanj.fnst@cn.fujitsu.com>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>

As pointed out by Eric Dumazet, net->ipv6.ip6_rt_last_gc should
hold the last time garbage collector was run so that we should
update it whenever fib6_run_gc() calls fib6_clean_all(), not only
if we got there from ip6_dst_gc().
Signed-off-by: NMichal Kubecek <mkubecek@suse.cz>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

On a high-traffic router with many processors and many IPv6 dst
entries, soft lockup in fib6_run_gc() can occur when number of
entries reaches gc_thresh.

This happens because fib6_run_gc() uses fib6_gc_lock to allow
only one thread to run the garbage collector but ip6_dst_gc()
doesn't update net->ipv6.ip6_rt_last_gc until fib6_run_gc()
returns. On a system with many entries, this can take some time
so that in the meantime, other threads pass the tests in
ip6_dst_gc() (ip6_rt_last_gc is still not updated) and wait for
the lock. They then have to run the garbage collector one after
another which blocks them for quite long.

Resolve this by replacing special value ~0UL of expire parameter
to fib6_run_gc() by explicit "force" parameter to choose between
spin_lock_bh() and spin_trylock_bh() and call fib6_run_gc() with
force=false if gc_thresh is reached but not max_size.
Signed-off-by: NMichal Kubecek <mkubecek@suse.cz>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Current net name space has only one genid for both IPv4 and IPv6, it has below
drawbacks:

- Add/delete an IPv4 address will invalidate all IPv6 routing table entries.
- Insert/remove XFRM policy will also invalidate both IPv4/IPv6 routing table
  entries even when the policy is only applied for one address family.

Thus, this patch attempt to split one genid for two to cater for IPv4 and IPv6
separately in a fine granularity.
Signed-off-by: NFan Du <fan.du@windriver.com>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Seting rt->rt6i_nsiblings to zero is rebundant, because above memset
zeroed the rest of rt excluding the first dst memember.
Signed-off-by: NFan Du <fan.du@windriver.com>
Acked-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This is a follow-up patch to 3630d400
("ipv6: rt6_check_neigh should successfully verify neigh if no NUD
information are available").

Since the removal of rt->n in rt6_info we can end up with a dst ==
NULL in rt6_check_neigh. In case the kernel is not compiled with
CONFIG_IPV6_ROUTER_PREF we should also select a route with unkown
NUD state but we must not avoid doing round robin selection on routes
with the same target. So introduce and pass down a boolean ``do_rr'' to
indicate when we should update rt->rr_ptr. As soon as no route is valid
we do backtracking and do a lookup on a higher level in the fib trie.

v2:
a) Improved rt6_check_neigh logic (no need to create neighbour there)
   and documented return values.

v3:
a) Introduce enum rt6_nud_state to get rid of the magic numbers
   (thanks to David Miller).
b) Update and shorten commit message a bit to actualy reflect
   the source.
Reported-by: NPierre Emeriaud <petrus.lt@gmail.com>
Cc: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We could end up expiring a route which is part of an ecmp route set. Doing
so would invalidate the rt->rt6i_nsiblings calculations and could provoke
the following panic:

[   80.144667] ------------[ cut here ]------------
[   80.145172] kernel BUG at net/ipv6/ip6_fib.c:733!
[   80.145172] invalid opcode: 0000 [#1] SMP
[   80.145172] Modules linked in: 8021q nf_conntrack_netbios_ns nf_conntrack_broadcast ipt_MASQUERADE ip6table_mangle ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 iptable_nat nf_nat_ipv4 nf_nat iptable_mangle nf_conntrack_ipv4 nf_defrag_ipv4 xt_conntrack nf_conntrack ebtable_filter ebtables ip6table_filter ip6_tables
+snd_hda_intel snd_hda_codec snd_hwdep snd_seq snd_seq_device snd_pcm snd_page_alloc snd_timer virtio_balloon snd soundcore i2c_piix4 i2c_core virtio_net virtio_blk
[   80.145172] CPU: 1 PID: 786 Comm: ping6 Not tainted 3.10.0+ #118
[   80.145172] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   80.145172] task: ffff880117fa0000 ti: ffff880118770000 task.ti: ffff880118770000
[   80.145172] RIP: 0010:[<ffffffff815f3b5d>]  [<ffffffff815f3b5d>] fib6_add+0x75d/0x830
[   80.145172] RSP: 0018:ffff880118771798  EFLAGS: 00010202
[   80.145172] RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff88011350e480
[   80.145172] RDX: ffff88011350e238 RSI: 0000000000000004 RDI: ffff88011350f738
[   80.145172] RBP: ffff880118771848 R08: ffff880117903280 R09: 0000000000000001
[   80.145172] R10: 0000000000000000 R11: 0000000000000000 R12: ffff88011350f680
[   80.145172] R13: ffff880117903280 R14: ffff880118771890 R15: ffff88011350ef90
[   80.145172] FS:  00007f02b5127740(0000) GS:ffff88011fd00000(0000) knlGS:0000000000000000
[   80.145172] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[   80.145172] CR2: 00007f981322a000 CR3: 00000001181b1000 CR4: 00000000000006e0
[   80.145172] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   80.145172] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[   80.145172] Stack:
[   80.145172]  0000000000000001 ffff880100000000 ffff880100000000 ffff880117903280
[   80.145172]  0000000000000000 ffff880119a4cf00 0000000000000400 00000000000007fa
[   80.145172]  0000000000000000 0000000000000000 0000000000000000 ffff88011350f680
[   80.145172] Call Trace:
[   80.145172]  [<ffffffff815eeceb>] ? rt6_bind_peer+0x4b/0x90
[   80.145172]  [<ffffffff815ed985>] __ip6_ins_rt+0x45/0x70
[   80.145172]  [<ffffffff815eee35>] ip6_ins_rt+0x35/0x40
[   80.145172]  [<ffffffff815ef1e4>] ip6_pol_route.isra.44+0x3a4/0x4b0
[   80.145172]  [<ffffffff815ef34a>] ip6_pol_route_output+0x2a/0x30
[   80.145172]  [<ffffffff81616077>] fib6_rule_action+0xd7/0x210
[   80.145172]  [<ffffffff815ef320>] ? ip6_pol_route_input+0x30/0x30
[   80.145172]  [<ffffffff81553026>] fib_rules_lookup+0xc6/0x140
[   80.145172]  [<ffffffff81616374>] fib6_rule_lookup+0x44/0x80
[   80.145172]  [<ffffffff815ef320>] ? ip6_pol_route_input+0x30/0x30
[   80.145172]  [<ffffffff815edea3>] ip6_route_output+0x73/0xb0
[   80.145172]  [<ffffffff815dfdf3>] ip6_dst_lookup_tail+0x2c3/0x2e0
[   80.145172]  [<ffffffff813007b1>] ? list_del+0x11/0x40
[   80.145172]  [<ffffffff81082a4c>] ? remove_wait_queue+0x3c/0x50
[   80.145172]  [<ffffffff815dfe4d>] ip6_dst_lookup_flow+0x3d/0xa0
[   80.145172]  [<ffffffff815fda77>] rawv6_sendmsg+0x267/0xc20
[   80.145172]  [<ffffffff815a8a83>] inet_sendmsg+0x63/0xb0
[   80.145172]  [<ffffffff8128eb93>] ? selinux_socket_sendmsg+0x23/0x30
[   80.145172]  [<ffffffff815218d6>] sock_sendmsg+0xa6/0xd0
[   80.145172]  [<ffffffff81524a68>] SYSC_sendto+0x128/0x180
[   80.145172]  [<ffffffff8109825c>] ? update_curr+0xec/0x170
[   80.145172]  [<ffffffff81041d09>] ? kvm_clock_get_cycles+0x9/0x10
[   80.145172]  [<ffffffff810afd1e>] ? __getnstimeofday+0x3e/0xd0
[   80.145172]  [<ffffffff8152509e>] SyS_sendto+0xe/0x10
[   80.145172]  [<ffffffff8164efd9>] system_call_fastpath+0x16/0x1b
[   80.145172] Code: fe ff ff 41 f6 45 2a 06 0f 85 ca fe ff ff 49 8b 7e 08 4c 89 ee e8 94 ef ff ff e9 b9 fe ff ff 48 8b 82 28 05 00 00 e9 01 ff ff ff <0f> 0b 49 8b 54 24 30 0d 00 00 40 00 89 83 14 01 00 00 48 89 53
[   80.145172] RIP  [<ffffffff815f3b5d>] fib6_add+0x75d/0x830
[   80.145172]  RSP <ffff880118771798>
[   80.387413] ---[ end trace 02f20b7a8b81ed95 ]---
[   80.390154] Kernel panic - not syncing: Fatal exception in interrupt

Cc: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Cc: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

After the removal of rt->n we do not create a neighbour entry at route
insertion time (rt6_bind_neighbour is gone). As long as no neighbour is
created because of "useful traffic" we skip this routing entry because
rt6_check_neigh cannot pick up a valid neighbour (neigh == NULL) and
thus returns false.

This change was introduced by commit
887c95cc ("ipv6: Complete neighbour
entry removal from dst_entry.")

To quote RFC4191:
"If the host has no information about the router's reachability, then
the host assumes the router is reachable."

and also:
"A host MUST NOT probe a router's reachability in the absence of useful
traffic that the host would have sent to the router if it were reachable."

So, just assume the router is reachable and let's rt6_probe do the
rest. We don't need to create a neighbour on route insertion time.

If we don't compile with CONFIG_IPV6_ROUTER_PREF (RFC4191 support)
a neighbour is only valid if its nud_state is NUD_VALID. I did not find
any references that we should probe the router on route insertion time
via the other RFCs. So skip this route in that case.

v2:
a) use IS_ENABLED instead of #ifdefs (thanks to Sergei Shtylyov)
Reported-by: NPierre Emeriaud <petrus.lt@gmail.com>
Cc: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There is no reason to skip ECMP lookup when oif is specified, but this implies
to check oif given by user when selecting another route.
When the new route does not match oif requirement, we simply keep the initial
one.
Spotted-by: Ndingzhi <zhi.ding@6wind.com>
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Reduce the uses of this unnecessary typedef.

Done via perl script:

$ git grep --name-only -w ctl_table net | \
  xargs perl -p -i -e '\
	sub trim { my ($local) = @_; $local =~ s/(^\s+|\s+$)//g; return $local; } \
        s/\b(?<!struct\s)ctl_table\b(\s*\*\s*|\s+\w+)/"struct ctl_table " . trim($1)/ge'

Reflow the modified lines that now exceed 80 columns.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This corrects an regression introduced by "net: Use 16bits for *_headers
fields of struct skbuff" when NET_SKBUFF_DATA_USES_OFFSET is not set. In
that case skb->tail will be a pointer whereas skb->transport_header
will be an offset from head. This is corrected by using wrappers that
ensure that comparisons and calculations are always made using pointers.
Signed-off-by: NSimon Horman <horms@verge.net.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

So far, only net_device * could be passed along with netdevice notifier
event. This patch provides a possibility to pass custom structure
able to provide info that event listener needs to know.
Signed-off-by: NJiri Pirko <jiri@resnulli.us>

v2->v3: fix typo on simeth
	shortened dev_getter
	shortened notifier_info struct name
v1->v2: fix notifier_call parameter in call_netdevice_notifier()
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

With decnet converted, we can finally get rid of rta_buf and its
computations around it. It also gets rid of the minimal header
length verification since all message handlers do that explicitly
anyway.
Signed-off-by: NThomas Graf <tgraf@suug.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Setting net.ipv6.conf.<interface>.accept_ra=2 causes the kernel
to accept RAs even when forwarding is enabled. However, enabling
forwarding purges all default routes on the system, breaking
connectivity until the next RA is received. Fix this by not
purging default routes on interfaces that have accept_ra=2.
Signed-off-by: NLorenzo Colitti <lorenzo@google.com>
Acked-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Acked-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Eric Dumazet wrote:
| Some strange crashes happen in rt6_check_expired(), with access
| to random addresses.
|
| At first glance, it looks like the RTF_EXPIRES and
| stuff added in commit 1716a961
| (ipv6: fix problem with expired dst cache)
| are racy : same dst could be manipulated at the same time
| on different cpus.
|
| At some point, our stack believes rt->dst.from contains a dst pointer,
| while its really a jiffie value (as rt->dst.expires shares the same area
| of memory)
|
| rt6_update_expires() should be fixed, or am I missing something ?
|
| CC Neil because of https://bugzilla.redhat.com/show_bug.cgi?id=892060

Because we do not have any locks for dst_entry, we cannot change
essential structure in the entry; e.g., we cannot change reference
to other entity.

To fix this issue, split 'from' and 'expires' field in dst_entry
out of union.  Once it is 'from' is assigned in the constructor,
keep the reference until the very last stage of the life time of
the object.

Of course, it is unsafe to change 'from', so make rt6_set_from simple
just for fresh entries.
Reported-by: NEric Dumazet <eric.dumazet@gmail.com>
Reported-by: NNeil Horman <nhorman@tuxdriver.com>
CC: Gao Feng <gaofeng@cn.fujitsu.com>
Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Reviewed-by: NEric Dumazet <edumazet@google.com>
Reported-by: NSteinar H. Gunderson <sesse@google.com>
Reviewed-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

proc_net_remove is only used to remove proc entries
that under /proc/net,it's not a general function for
removing proc entries of netns. if we want to remove
some proc entries which under /proc/net/stat/, we still
need to call remove_proc_entry.

this patch use remove_proc_entry to replace proc_net_remove.
we can remove proc_net_remove after this patch.
Signed-off-by: NGao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Right now, some modules such as bonding use proc_create
to create proc entries under /proc/net/, and other modules
such as ipv4 use proc_net_fops_create.

It looks a little chaos.this patch changes all of
proc_net_fops_create to proc_create. we can remove
proc_net_fops_create after this patch.
Signed-off-by: NGao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

They will be created at output, if ever needed. This avoids creating
empty neighbor entries when TPROXYing/Forwarding packets for addresses
that are not even directly reachable.

Note that IPv4 already handles it this way. No neighbor entries are
created for local input.

Tested by myself and customer.
Signed-off-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NMarcelo Ricardo Leitner <mleitner@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit 2152caea ("ipv6: Do not depend on rt->n in rt6_probe().")
introduce a bug to try to update "updated" time in neighbour
structure.
Update the "updated" time only if neighbour is available.

Bug was found by Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Because of rt->n removal, we do not need neigh argument any more.
Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

CC: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>