Commit graph

822 commits

Author SHA1 Message Date
David Ahern b75cc8f90f net/ipv6: Pass skb to route lookup
IPv6 does path selection for multipath routes deep in the lookup
functions. The next patch adds L4 hash option and needs the skb
for the forward path. To get the skb to the relevant FIB lookup
functions it needs to go through the fib rules layer, so add a
lookup_data argument to the fib_lookup_arg struct.

Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-04 13:04:22 -05:00
David Ahern 9a2a537acc net/ipv6: Make rt6_multipath_hash similar to fib_multipath_hash
Make rt6_multipath_hash more of a direct parallel to fib_multipath_hash
and reduce stack and overhead in the process: get_hash_from_flowi6 is
just a wrapper around __get_hash_from_flowi6 with another stack
allocation for flow_keys. Move setting the addresses, protocol and
label into rt6_multipath_hash and allow it to make the call to
flow_hash_from_keys.

Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-04 13:04:21 -05:00
David Ahern 6f74b6c259 net: Align ip_multipath_l3_keys and ip6_multipath_l3_keys
Symmetry is good and allows easy comparison that ipv4 and ipv6 are
doing the same thing. To that end, change ip_multipath_l3_keys to
set addresses at the end after the icmp compares, and move the
initialization of ipv6 flow keys to rt6_multipath_hash.

Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-04 13:04:21 -05:00
Roopa Prabhu 5e5d6fed37 ipv6: route: dissect flow in input path if fib rules need it
Dissect flow in fwd path if fib rules require it. Controlled by
a flag to avoid penatly for the common case. Flag is set when fib
rules with sport, dport and proto match that require flow dissect
are installed. Also passes the dissected hash keys to the multipath
hash function when applicable to avoid dissecting the flow again.
icmp packets will continue to use inner header for hash
calculations.

Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-28 22:44:44 -05:00
Kirill Tkhai 85ca51b2a2 net: Convert ipv6_inetpeer_ops
net->ipv6.peers is dereferenced in three places via inet_getpeer_v6(),
and it's used to handle skb. All the users of inet_getpeer_v6() do not
look like be able to be called from foreign net pernet_operations, so
we may mark them as async.

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-19 14:19:10 -05:00
Kirill Tkhai 509114112d net: Convert raw6_net_ops, udplite6_net_ops, ipv6_proc_ops, if6_proc_net_ops and ip6_route_net_late_ops
These pernet_operations create and destroy /proc entries
and safely may be converted and safely may be mark as async.

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-19 14:19:10 -05:00
Xin Long 510c321b55 xfrm: reuse uncached_list to track xdsts
In early time, when freeing a xdst, it would be inserted into
dst_garbage.list first. Then if it's refcnt was still held
somewhere, later it would be put into dst_busy_list in
dst_gc_task().

When one dev was being unregistered, the dev of these dsts in
dst_busy_list would be set with loopback_dev and put this dev.
So that this dev's removal wouldn't get blocked, and avoid the
kmsg warning:

  kernel:unregister_netdevice: waiting for veth0 to become \
  free. Usage count = 2

However after Commit 52df157f17 ("xfrm: take refcnt of dst
when creating struct xfrm_dst bundle"), the xdst will not be
freed with dst gc, and this warning happens.

To fix it, we need to find these xdsts that are still held by
others when removing the dev, and free xdst's dev and set it
with loopback_dev.

But unfortunately after flow_cache for xfrm was deleted, no
list tracks them anymore. So we need to save these xdsts
somewhere to release the xdst's dev later.

To make this easier, this patch is to reuse uncached_list to
track xdsts, so that the dev refcnt can be released in the
event NETDEV_UNREGISTER process of fib_netdev_notifier.

Thanks to Florian, we could move forward this fix quickly.

Fixes: 52df157f17 ("xfrm: take refcnt of dst when creating struct xfrm_dst bundle")
Reported-by: Jianlin Shi <jishi@redhat.com>
Reported-by: Hangbin Liu <liuhangbin@gmail.com>
Tested-by: Eyal Birger <eyal.birger@gmail.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2018-02-16 07:03:33 +01:00
David Ahern 9942895b5e net: Move ipv4 set_lwt_redirect helper to lwtunnel
IPv4 uses set_lwt_redirect to set the lwtunnel redirect functions as
needed. Move it to lwtunnel.h as lwtunnel_set_redirect and change
IPv6 to also use it.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-14 14:43:32 -05:00
David Ahern 44750f8483 net/ipv6: onlink nexthop checks should default to main table
Because of differences in how ipv4 and ipv6 handle fib lookups,
verification of nexthops with onlink flag need to default to the main
table rather than the local table used by IPv4. As it stands an
address within a connected route on device 1 can be used with
onlink on device 2. Updating the table properly rejects the route
due to the egress device mismatch.

Update the extack message as well to show it could be a device
mismatch for the nexthop spec.

Fixes: fc1e64e109 ("net/ipv6: Add support for onlink flag")
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-07 21:52:42 -05:00
David Ahern 58e354c01b net/ipv6: Handle reject routes with onlink flag
Verification of nexthops with onlink flag need to handle unreachable
routes. The lookup is only intended to validate the gateway address
is not a local address and if the gateway resolves the egress device
must match the given device. Hence, hitting any default reject route
is ok.

Fixes: fc1e64e109 ("net/ipv6: Add support for onlink flag")
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-07 21:52:06 -05:00
Wei Wang 31afeb425f ipv6: change route cache aging logic
In current route cache aging logic, if a route has both RTF_EXPIRE and
RTF_GATEWAY set, the route will only be removed if the neighbor cache
has no NTF_ROUTER flag. Otherwise, even if the route has expired, it
won't get deleted.
Fix this logic to always check if the route has expired first and then
do the gateway neighbor cache check if previous check decide to not
remove the exception entry.

Fixes: 1859bac04f ("ipv6: remove from fib tree aged out RTF_CACHE dst")
Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-29 14:22:05 -05:00
David Ahern fc1e64e109 net/ipv6: Add support for onlink flag
Similar to IPv4 allow routes to be added with the RTNH_F_ONLINK flag.
The onlink option requires a gateway and a nexthop device. Any unicast
gateway is allowed (including IPv4 mapped addresses and unresolved
ones) as long as the gateway is not a local address and if it resolves
it must match the given device.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-26 10:16:43 -05:00
David Ahern f4797b33db net/ipv6: Add flags and table id to ip6_nh_lookup_table
onlink verification needs to do a lookup in potentially different
table than the table in fib6_config and without the RT6_LOOKUP_F_IFACE
flag. Change ip6_nh_lookup_table to take table id and flags as input
arguments. Both verifications want to ignore link state, so add that
flag can stay in the lookup helper.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-26 10:16:42 -05:00
David Ahern 1edce99fa8 net/ipv6: Move gateway validation into helper
Move existing code to validate nexthop into a helper. Follow on patch
adds support for nexthops marked with onlink, and this helper keeps
the complexity of ip6_route_info_create in check.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-26 10:16:42 -05:00
David Ahern 955ec4cb3b net/ipv6: Do not allow route add with a device that is down
IPv6 allows routes to be installed when the device is not up (admin up).
Worse, it does not mark it as LINKDOWN. IPv4 does not allow it and really
there is no reason for IPv6 to allow it, so check the flags and deny if
device is admin down.

Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-25 16:22:02 -05:00
Alexey Dobriyan 96890d6252 net: delete /proc THIS_MODULE references
/proc has been ignoring struct file_operations::owner field for 10 years.
Specifically, it started with commit 786d7e1612
("Fix rmmod/read/write races in /proc entries"). Notice the chunk where
inode->i_fop is initialized with proxy struct file_operations for
regular files:

	-               if (de->proc_fops)
	-                       inode->i_fop = de->proc_fops;
	+               if (de->proc_fops) {
	+                       if (S_ISREG(inode->i_mode))
	+                               inode->i_fop = &proc_reg_file_ops;
	+                       else
	+                               inode->i_fop = de->proc_fops;
	+               }

VFS stopped pinning module at this point.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-16 15:01:33 -05:00
Ido Schimmel 6802f3adcb ipv6: Fix build with gcc-4.4.5
Emil reported the following compiler errors:

net/ipv6/route.c: In function `rt6_sync_up`:
net/ipv6/route.c:3586: error: unknown field `nh_flags` specified in initializer
net/ipv6/route.c:3586: warning: missing braces around initializer
net/ipv6/route.c:3586: warning: (near initialization for `arg.<anonymous>`)
net/ipv6/route.c: In function `rt6_sync_down_dev`:
net/ipv6/route.c:3695: error: unknown field `event` specified in initializer
net/ipv6/route.c:3695: warning: missing braces around initializer
net/ipv6/route.c:3695: warning: (near initialization for `arg.<anonymous>`)

Problem is with the named initializers for the anonymous union members.
Fix this by adding curly braces around the initialization.

Fixes: 4c981e28d3 ("ipv6: Prepare to handle multiple netdev events")
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reported-by: Emil S Tantilov <emils.tantilov@gmail.com>
Tested-by: Emil S Tantilov <emils.tantilov@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-15 14:28:05 -05:00
Ido Schimmel 398958ae48 ipv6: Add support for non-equal-cost multipath
The use of hash-threshold instead of modulo-N makes it trivial to add
support for non-equal-cost multipath.

Instead of dividing the multipath hash function's output space equally
between the nexthops, each nexthop is assigned a region size which is
proportional to its weight.

Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-10 15:14:44 -05:00
Ido Schimmel 3d709f69a3 ipv6: Use hash-threshold instead of modulo-N
Now that each nexthop stores its region boundary in the multipath hash
function's output space, we can use hash-threshold instead of modulo-N
in multipath selection.

This reduces the number of checks we need to perform during lookup, as
dead and linkdown nexthops are assigned a negative region boundary. In
addition, in contrast to modulo-N, only flows near region boundaries are
affected when a nexthop is added or removed.

Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-10 15:14:44 -05:00
Ido Schimmel 7696c06a18 ipv6: Use a 31-bit multipath hash
The hash thresholds assigned to IPv6 nexthops are in the range of
[-1, 2^31 - 1], where a negative value is assigned to nexthops that
should not be considered during multipath selection.

Therefore, in a similar fashion to IPv4, we need to use the upper
31-bits of the multipath hash for multipath selection.

Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-10 15:14:44 -05:00
Ido Schimmel d7dedee184 ipv6: Calculate hash thresholds for IPv6 nexthops
Before we convert IPv6 to use hash-threshold instead of modulo-N, we
first need each nexthop to store its region boundary in the hash
function's output space.

The boundary is calculated by dividing the output space equally between
the different active nexthops. That is, nexthops that are not dead or
linkdown.

The boundaries are rebalanced whenever a nexthop is added or removed to
a multipath route and whenever a nexthop becomes active or inactive.

Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-10 15:14:44 -05:00
Ido Schimmel 1de178edc7 ipv6: Flush multipath routes when all siblings are dead
By default, IPv6 deletes nexthops from a multipath route when the
nexthop device is put administratively down. This differs from IPv4
where the nexthops are kept, but marked with the RTNH_F_DEAD flag. A
multipath route is flushed when all of its nexthops become dead.

Align IPv6 with IPv4 and have it conform to the same guidelines.

In case the multipath route needs to be flushed, its siblings are
flushed one by one. Otherwise, the nexthops are marked with the
appropriate flags and the tree walker is instructed to skip all the
siblings.

As explained in previous patches, care is taken to update the sernum of
the affected tree nodes, so as to prevent the use of wrong dst entries.

Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-07 21:29:41 -05:00
Ido Schimmel 922c2ac82e ipv6: Take table lock outside of sernum update function
The next patch is going to allow dead routes to remain in the FIB tree
in certain situations.

When this happens we need to be sure to bump the sernum of the nodes
where these are stored so that potential copies cached in sockets are
invalidated.

The function that performs this update assumes the table lock is not
taken when it is invoked, but that will not be the case when it is
invoked by the tree walker.

Have the function assume the lock is taken and make the single caller
take the lock itself.

Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-07 21:29:41 -05:00
Ido Schimmel f9d882ea57 ipv6: Report dead flag during route dump
Up until now the RTNH_F_DEAD flag was only reported in route dump when
the 'ignore_routes_with_linkdown' sysctl was set. This is expected as
dead routes were flushed otherwise.

The reliance on this sysctl is going to be removed, so we need to report
the flag regardless of the sysctl's value.

Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-07 21:29:40 -05:00
Ido Schimmel 8067bb8c1d ipv6: Ignore dead routes during lookup
Currently, dead routes are only present in the routing tables in case
the 'ignore_routes_with_linkdown' sysctl is set. Otherwise, they are
flushed.

Subsequent patches are going to remove the reliance on this sysctl and
make IPv6 more consistent with IPv4.

Before this is done, we need to make sure dead routes are skipped during
route lookup, so as to not cause packet loss.

Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-07 21:29:40 -05:00
Ido Schimmel 44c9f2f206 ipv6: Check nexthop flags in route dump instead of carrier
Similar to previous patch, there is no need to check for the carrier of
the nexthop device when dumping the route and we can instead check for
the presence of the RTNH_F_LINKDOWN flag.

Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-07 21:29:40 -05:00
Ido Schimmel 14c5206c2d ipv6: Check nexthop flags during route lookup instead of carrier
Now that the RTNH_F_LINKDOWN flag is set in nexthops, we can avoid the
need to dereference the nexthop device and check its carrier and instead
check for the presence of the flag.

Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-07 21:29:40 -05:00
Ido Schimmel 5609b80a37 ipv6: Set nexthop flags during route creation
It is valid to install routes with a nexthop device that does not have a
carrier, so we need to make sure they're marked accordingly.

As explained in the previous patch, host and anycast routes are never
marked with the 'linkdown' flag.

Note that reject routes are unaffected, as these use the loopback device
which always has a carrier.

Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-07 21:29:40 -05:00
Ido Schimmel 27c6fa73f9 ipv6: Set nexthop flags upon carrier change
Similar to IPv4, when the carrier of a netdev changes we should toggle
the 'linkdown' flag on all the nexthops using it as their nexthop
device.

This will later allow us to test for the presence of this flag during
route lookup and dump.

Up until commit 4832c30d54 ("net: ipv6: put host and anycast routes on
device with address") host and anycast routes used the loopback netdev
as their nexthop device and thus were not marked with the 'linkdown'
flag. The patch preserves this behavior and allows one to ping the local
address even when the nexthop device does not have a carrier and the
'ignore_routes_with_linkdown' sysctl is set.

Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-07 21:29:40 -05:00
Ido Schimmel 4c981e28d3 ipv6: Prepare to handle multiple netdev events
To make IPv6 more in line with IPv4 we need to be able to respond
differently to different netdev events. For example, when a netdev is
unregistered all the routes using it as their nexthop device should be
flushed, whereas when the netdev's carrier changes only the 'linkdown'
flag should be toggled.

Currently, this is not possible, as the function that traverses the
routing tables is not aware of the triggering event.

Propagate the triggering event down, so that it could be used in later
patches.

Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-07 21:29:40 -05:00
Ido Schimmel 2127d95aef ipv6: Clear nexthop flags upon netdev up
Previous patch marked nexthops with the 'dead' and 'linkdown' flags.
Clear these flags when the netdev comes back up.

Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-07 21:29:39 -05:00
Ido Schimmel 2b2413610e ipv6: Mark dead nexthops with appropriate flags
When a netdev is put administratively down or unregistered all the
nexthops using it as their nexthop device should be marked with the
'dead' and 'linkdown' flags.

Currently, when a route is dumped its nexthop device is tested and the
flags are set accordingly. A similar check is performed during route
lookup.

Instead, we can simply mark the nexthops based on netdev events and
avoid checking the netdev's state during route dump and lookup.

Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-07 21:29:39 -05:00
Ido Schimmel 9fcb0714dc ipv6: Remove redundant route flushing during namespace dismantle
By the time fib6_net_exit() is executed all the netdevs in the namespace
have been either unregistered or pushed back to the default namespace.
That is because pernet subsys operations are always ordered before
pernet device operations and therefore invoked after them during
namespace dismantle.

Thus, all the routing tables in the namespace are empty by the time
fib6_net_exit() is invoked and the call to rt6_ifdown() can be removed.

This allows us to simplify the condition in fib6_ifdown() as it's only
ever called with an actual netdev.

Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-07 21:29:39 -05:00
David S. Miller fba961ab29 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Lots of overlapping changes.  Also on the net-next side
the XDP state management is handled more in the generic
layers so undo the 'net' nfp fix which isn't applicable
in net-next.

Include a necessary change by Jakub Kicinski, with log message:

====================
cls_bpf no longer takes care of offload tracking.  Make sure
netdevsim performs necessary checks.  This fixes a warning
caused by TC trying to remove a filter it has not added.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-22 11:16:31 -05:00
Ido Schimmel 58acfd714e ipv6: Honor specified parameters in fibmatch lookup
Currently, parameters such as oif and source address are not taken into
account during fibmatch lookup. Example (IPv4 for reference) before
patch:

$ ip -4 route show
192.0.2.0/24 dev dummy0 proto kernel scope link src 192.0.2.1
198.51.100.0/24 dev dummy1 proto kernel scope link src 198.51.100.1

$ ip -6 route show
2001:db8:1::/64 dev dummy0 proto kernel metric 256 pref medium
2001:db8:2::/64 dev dummy1 proto kernel metric 256 pref medium
fe80::/64 dev dummy0 proto kernel metric 256 pref medium
fe80::/64 dev dummy1 proto kernel metric 256 pref medium

$ ip -4 route get fibmatch 192.0.2.2 oif dummy0
192.0.2.0/24 dev dummy0 proto kernel scope link src 192.0.2.1
$ ip -4 route get fibmatch 192.0.2.2 oif dummy1
RTNETLINK answers: No route to host

$ ip -6 route get fibmatch 2001:db8:1::2 oif dummy0
2001:db8:1::/64 dev dummy0 proto kernel metric 256 pref medium
$ ip -6 route get fibmatch 2001:db8:1::2 oif dummy1
2001:db8:1::/64 dev dummy0 proto kernel metric 256 pref medium

After:

$ ip -6 route get fibmatch 2001:db8:1::2 oif dummy0
2001:db8:1::/64 dev dummy0 proto kernel metric 256 pref medium
$ ip -6 route get fibmatch 2001:db8:1::2 oif dummy1
RTNETLINK answers: Network is unreachable

The problem stems from the fact that the necessary route lookup flags
are not set based on these parameters.

Instead of duplicating the same logic for fibmatch, we can simply
resolve the original route from its copy and dump it instead.

Fixes: 18c3a61c42 ("net: ipv6: RTM_GETROUTE: return matched fib result when requested")
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-21 11:51:06 -05:00
Brendan McGrath 588753f1eb ipv6: icmp6: Allow icmp messages to be looped back
One example of when an ICMPv6 packet is required to be looped back is
when a host acts as both a Multicast Listener and a Multicast Router.

A Multicast Router will listen on address ff02::16 for MLDv2 messages.

Currently, MLDv2 messages originating from a Multicast Listener running
on the same host as the Multicast Router are not being delivered to the
Multicast Router. This is due to dst.input being assigned the default
value of dst_discard.

This results in the packet being looped back but discarded before being
delivered to the Multicast Router.

This patch sets dst.input to ip6_input to ensure a looped back packet
is delivered to the Multicast Router.

Signed-off-by: Brendan McGrath <redmcg@redmandi.dyndns.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-16 22:51:26 -05:00
Florian Westphal 16feebcf23 rtnetlink: remove __rtnl_register
This removes __rtnl_register and switches callers to either
rtnl_register or rtnl_register_module.

Also, rtnl_register() will now print an error if memory allocation
failed rather than panic the kernel.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-04 11:32:53 -05:00
David Miller 0f6c480f23 xfrm: Move dst->path into struct xfrm_dst
The first member of an IPSEC route bundle chain sets it's dst->path to
the underlying ipv4/ipv6 route that carries the bundle.

Stated another way, if one were to follow the xfrm_dst->child chain of
the bundle, the final non-NULL pointer would be the path and point to
either an ipv4 or an ipv6 route.

This is largely used to make sure that PMTU events propagate down to
the correct ipv4 or ipv6 route.

When we don't have the top of an IPSEC bundle 'dst->path == dst'.

Move it down into xfrm_dst and key off of dst->xfrm.

Signed-off-by: David S. Miller <davem@davemloft.net>
Reviewed-by: Eric Dumazet <edumazet@google.com>
2017-11-30 09:54:26 -05:00
David Miller 3a2232e92e ipv6: Move dst->from into struct rt6_info.
The dst->from value is only used by ipv6 routes to track where
a route "came from".

Any time we clone or copy a core ipv6 route in the ipv6 routing
tables, we have the copy/clone's ->from point to the base route.

This is used to handle route expiration properly.

Only ipv6 uses this mechanism, and only ipv6 code references
it.  So it is safe to move it into rt6_info.

Signed-off-by: David S. Miller <davem@davemloft.net>
Reviewed-by: Eric Dumazet <edumazet@google.com>
2017-11-30 09:54:26 -05:00
David Miller 071fb37ec4 ipv6: Move rt6_next from dst_entry into ipv6 route structure.
Signed-off-by: David S. Miller <davem@davemloft.net>
Reviewed-by: Eric Dumazet <edumazet@google.com>
2017-11-30 09:54:25 -05:00
David Ahern 98d11291d1 net: ipv6: Fixup device for anycast routes during copy
Florian reported a breakage with anycast routes due to commit
4832c30d54 ("net: ipv6: put host and anycast routes on device with
address"). Prior to this commit anycast routes were added against the
loopback device causing repetitive route entries with no insight into
why they existed. e.g.:
  $ ip -6 ro ls  table local type anycast
  anycast 2001:db8:1:: dev lo proto kernel metric 0 pref medium
  anycast 2001:db8:2:: dev lo proto kernel metric 0 pref medium
  anycast fe80:: dev lo proto kernel metric 0 pref medium
  anycast fe80:: dev lo proto kernel metric 0 pref medium

The point of commit 4832c30d54 is to add the routes using the device
with the address which is causing the route to be added. e.g.,:
  $ ip -6 ro ls  table local type anycast
  anycast 2001:db8:1:: dev eth1 proto kernel metric 0 pref medium
  anycast 2001:db8:2:: dev eth2 proto kernel metric 0 pref medium
  anycast fe80:: dev eth2 proto kernel metric 0 pref medium
  anycast fe80:: dev eth1 proto kernel metric 0 pref medium

For traffic to work as it did before, the dst device needs to be switched
to the loopback when the copy is created similar to local routes.

Fixes: 4832c30d54 ("net: ipv6: put host and anycast routes on device with address")
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-24 01:34:52 +09:00
Ido Schimmel bbfcd77631 ipv6: Do not consider linkdown nexthops during multipath
When the 'ignore_routes_with_linkdown' sysctl is set, we should not
consider linkdown nexthops during route lookup.

While the code correctly verifies that the initially selected route
('match') has a carrier, it does not perform the same check in the
subsequent multipath selection, resulting in a potential packet loss.

In case the chosen route does not have a carrier and the sysctl is set,
choose the initially selected route.

Fixes: 35103d1117 ("net: ipv6 sysctl option to ignore routes when nexthop link is down")
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Acked-by: David Ahern <dsahern@gmail.com>
Acked-by: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-24 01:26:47 +09:00
Stephen Hemminger 6670e15244 tcp: Namespace-ify sysctl_tcp_default_congestion_control
Make default TCP default congestion control to a per namespace
value. This changes default congestion control to a pointer to congestion ops
(rather than implicit as first element of available lsit).

The congestion control setting of new namespaces is inherited
from the current setting of the root namespace.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-15 14:09:52 +09:00
Wei Wang 2ea2352ede ipv6: prevent user from adding cached routes
Cached routes should only be created by the system when receiving pmtu
discovery or ip redirect msg. Users should not be allowed to create
cached routes.

Furthermore, after the patch series to move cached routes into exception
table, user added cached routes will trigger the following warning in
fib6_add():

WARNING: CPU: 0 PID: 2985 at net/ipv6/ip6_fib.c:1137
fib6_add+0x20d9/0x2c10 net/ipv6/ip6_fib.c:1137
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 2985 Comm: syzkaller320388 Not tainted 4.14.0-rc3+ #74
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:16 [inline]
 dump_stack+0x194/0x257 lib/dump_stack.c:52
 panic+0x1e4/0x417 kernel/panic.c:181
 __warn+0x1c4/0x1d9 kernel/panic.c:542
 report_bug+0x211/0x2d0 lib/bug.c:183
 fixup_bug+0x40/0x90 arch/x86/kernel/traps.c:178
 do_trap_no_signal arch/x86/kernel/traps.c:212 [inline]
 do_trap+0x260/0x390 arch/x86/kernel/traps.c:261
 do_error_trap+0x120/0x390 arch/x86/kernel/traps.c:298
 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:311
 invalid_op+0x18/0x20 arch/x86/entry/entry_64.S:905
RIP: 0010:fib6_add+0x20d9/0x2c10 net/ipv6/ip6_fib.c:1137
RSP: 0018:ffff8801cf09f6a0 EFLAGS: 00010297
RAX: ffff8801ce45e340 RBX: 1ffff10039e13eec RCX: ffff8801d749c814
RDX: 0000000000000000 RSI: ffff8801d749c700 RDI: ffff8801d749c780
RBP: ffff8801cf09fa08 R08: 0000000000000000 R09: ffff8801cf09f360
R10: ffff8801cf09f2d8 R11: 1ffff10039c8befb R12: 0000000000000001
R13: dffffc0000000000 R14: ffff8801d749c700 R15: ffffffff860655c0
 __ip6_ins_rt+0x6c/0x90 net/ipv6/route.c:1011
 ip6_route_add+0x148/0x1a0 net/ipv6/route.c:2782
 ipv6_route_ioctl+0x4d5/0x690 net/ipv6/route.c:3291
 inet6_ioctl+0xef/0x1e0 net/ipv6/af_inet6.c:521
 sock_do_ioctl+0x65/0xb0 net/socket.c:961
 sock_ioctl+0x2c2/0x440 net/socket.c:1058
 vfs_ioctl fs/ioctl.c:45 [inline]
 do_vfs_ioctl+0x1b1/0x1530 fs/ioctl.c:685
 SYSC_ioctl fs/ioctl.c:700 [inline]
 SyS_ioctl+0x8f/0xc0 fs/ioctl.c:691
 entry_SYSCALL_64_fastpath+0x1f/0xbe

So we fix this by failing the attemp to add cached routes from userspace
with returning EINVAL error.

Fixes: 2b760fcf5c ("ipv6: hook up exception table to store dst cache")
Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-29 12:18:58 +09:00
Wei Wang 87b1af8dcc ipv6: add ip6_null_entry check in rt6_select()
In rt6_select(), fn->leaf could be pointing to net->ipv6.ip6_null_entry.
In this case, we should directly return instead of trying to carry on
with the rest of the process.
If not, we could crash at:
  spin_lock_bh(&leaf->rt6i_table->rt6_lock);
because net->ipv6.ip6_null_entry does not have rt6i_table set.

Syzkaller recently reported following issue on net-next:
Use struct sctp_sack_info instead
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
sctp: [Deprecated]: syz-executor4 (pid 26496) Use of struct sctp_assoc_value in delayed_ack socket option.
Use struct sctp_sack_info instead
CPU: 1 PID: 26523 Comm: syz-executor6 Not tainted 4.14.0-rc4+ #85
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8801d147e3c0 task.stack: ffff8801a4328000
RIP: 0010:debug_spin_lock_before kernel/locking/spinlock_debug.c:83 [inline]
RIP: 0010:do_raw_spin_lock+0x23/0x1e0 kernel/locking/spinlock_debug.c:112
RSP: 0018:ffff8801a432ed70 EFLAGS: 00010207
RAX: dffffc0000000000 RBX: 0000000000000018 RCX: 0000000000000000
RDX: 0000000000000003 RSI: 0000000000000000 RDI: 000000000000001c
RBP: ffff8801a432ed90 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff8482b279 R12: ffff8801ce2ff3a0
sctp: [Deprecated]: syz-executor1 (pid 26546) Use of int in maxseg socket option.
Use struct sctp_assoc_value instead
R13: dffffc0000000000 R14: ffff8801d971e000 R15: ffff8801ce2ff0d8
FS:  00007f56e82f5700(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001ddbc22000 CR3: 00000001a4a04000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:136 [inline]
 _raw_spin_lock_bh+0x39/0x40 kernel/locking/spinlock.c:175
 spin_lock_bh include/linux/spinlock.h:321 [inline]
 rt6_select net/ipv6/route.c:786 [inline]
 ip6_pol_route+0x1be3/0x3bd0 net/ipv6/route.c:1650
sctp: [Deprecated]: syz-executor1 (pid 26576) Use of int in maxseg socket option.
Use struct sctp_assoc_value instead
TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies.  Check SNMP counters.
 ip6_pol_route_output+0x4c/0x60 net/ipv6/route.c:1843
 fib6_rule_lookup+0x9e/0x2a0 net/ipv6/ip6_fib.c:309
 ip6_route_output_flags+0x1f1/0x2b0 net/ipv6/route.c:1871
 ip6_route_output include/net/ip6_route.h:80 [inline]
 ip6_dst_lookup_tail+0x4ea/0x970 net/ipv6/ip6_output.c:953
 ip6_dst_lookup_flow+0xc8/0x270 net/ipv6/ip6_output.c:1076
 sctp_v6_get_dst+0x675/0x1c30 net/sctp/ipv6.c:274
 sctp_transport_route+0xa8/0x430 net/sctp/transport.c:287
 sctp_assoc_add_peer+0x4fe/0x1100 net/sctp/associola.c:656
 __sctp_connect+0x251/0xc80 net/sctp/socket.c:1187
 sctp_connect+0xb4/0xf0 net/sctp/socket.c:4209
 inet_dgram_connect+0x16b/0x1f0 net/ipv4/af_inet.c:541
 SYSC_connect+0x20a/0x480 net/socket.c:1642
 SyS_connect+0x24/0x30 net/socket.c:1623
 entry_SYSCALL_64_fastpath+0x1f/0xbe

Fixes: 66f5d6ce53 ("ipv6: replace rwlock with rcu and spinlock in fib6_table")
Signed-off-by: Wei Wang <weiwan@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-24 18:51:26 +09:00
Paolo Abeni b65f164d37 ipv6: let trace_fib6_table_lookup() dereference the fib table
The perf traces for ipv6 routing code show a relevant cost around
trace_fib6_table_lookup(), even if no trace is enabled. This is
due to the fib6_table de-referencing currently performed by the
caller.

Let's the tracing code pay this overhead, passing to the trace
helper the table pointer. This gives small but measurable
performance improvement under UDP flood.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: David Ahern <dsa@cumulusnetworks.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-21 02:23:38 +01:00
Paolo Abeni 1859bac04f ipv6: remove from fib tree aged out RTF_CACHE dst
The commit 2b760fcf5c ("ipv6: hook up exception table to store
dst cache") partially reverted the commit 1e2ea8ad37 ("ipv6: set
dst.obsolete when a cached route has expired").

As a result, RTF_CACHE dst referenced outside the fib tree will
not be removed until the next sernum change; dst_check() does not
fail on aged-out dst, and dst->__refcnt can't decrease: the aged
out dst will stay valid for a potentially unlimited time after the
timeout expiration.

This change explicitly removes RTF_CACHE dst from the fib tree when
aged out. The rt6_remove_exception() logic will then obsolete the
dst and other entities will drop the related reference on next
dst_check().

pMTU exceptions are not aged-out, and are removed from the exception
table only when the - usually considerably longer - ip6_rt_mtu_expires
timeout expires.

v1 -> v2:
  - do not touch dst.obsolete in rt6_remove_exception(), not needed
v2 -> v3:
  - take care of pMTU exceptions, too

Fixes: 2b760fcf5c ("ipv6: hook up exception table to store dst cache")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Wei Wang <weiwan@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-21 01:39:10 +01:00
Paolo Abeni b886d5f2f2 ipv6: start fib6 gc on RTF_CACHE dst creation
After the commit 2b760fcf5c ("ipv6: hook up exception table
to store dst cache"), the fib6 gc is not started after the
creation of a RTF_CACHE via a redirect or pmtu update, since
fib6_add() isn't invoked anymore for such dsts.

We need the fib6 gc to run periodically to clean the RTF_CACHE,
or the dst will stay there forever.

Fix it by explicitly calling fib6_force_start_gc() on successful
exception creation. gc_args->more accounting will ensure that
the gc timer will run for whatever time needed to properly
clean the table.

v2 -> v3:
 - clarified the commit message

Fixes: 2b760fcf5c ("ipv6: hook up exception table to store dst cache")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Wei Wang <weiwan@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-21 01:39:10 +01:00
Colin Ian King 442d713baa ipv6: fix incorrect bitwise operator used on rt6i_flags
The use of the | operator always leads to true which looks rather
suspect to me. Fix this by using & instead to just check the
RTF_CACHE entry bit.

Detected by CoverityScan, CID#1457734, #1457747 ("Wrong operator used")

Fixes: 35732d01fe ("ipv6: introduce a hash table to store dst cache")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Wei Wang <weiwan@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-10 12:24:15 -07:00
Colin Ian King b2427e6717 ipv6: fix dereference of rt6_ex before null check error
Currently rt6_ex is being dereferenced before it is null checked
hence there is a possible null dereference bug. Fix this by only
dereferencing rt6_ex after it has been null checked.

Detected by CoverityScan, CID#1457749 ("Dereference before null check")

Fixes: 81eb8447da ("ipv6: take care of rt6_stats")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-10 10:54:17 -07:00
David S. Miller d93fa2ba64 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-10-09 20:11:09 -07:00
Eric Dumazet bfd8e5a407 ipv6: avoid zeroing per cpu data again
per cpu allocations are already zeroed, no need to clear them again.

Fixes: d52d3997f8 ("ipv6: Create percpu rt6_info")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Tejun Heo <tj@kernel.org>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-09 10:29:39 -07:00
Steffen Klassert 62cf27e52b ipv6: Fix traffic triggered IPsec connections.
A recent patch removed the dst_free() on the allocated
dst_entry in ipv6_blackhole_route(). The dst_free() marked
the dst_entry as dead and added it to the gc list. I.e. it
was setup for a one time usage. As a result we may now have
a blackhole route cached at a socket on some IPsec scenarios.
This makes the connection unusable.

Fix this by marking the dst_entry directly at allocation time
as 'dead', so it is used only once.

Fixes: 587fea7411 ("ipv6: mark DST_NOGC and remove the operation of dst_free()")
Reported-by: Tobias Brunner <tobias@strongswan.org>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-09 09:39:26 -07:00
Eric Dumazet 951f788a80 ipv6: fix a BUG in rt6_get_pcpu_route()
Ido reported following splat and provided a patch.

[  122.221814] BUG: using smp_processor_id() in preemptible [00000000] code: sshd/2672
[  122.221845] caller is debug_smp_processor_id+0x17/0x20
[  122.221866] CPU: 0 PID: 2672 Comm: sshd Not tainted 4.14.0-rc3-idosch-next-custom #639
[  122.221880] Hardware name: Mellanox Technologies Ltd. MSN2100-CB2FO/SA001017, BIOS 5.6.5 06/07/2016
[  122.221893] Call Trace:
[  122.221919]  dump_stack+0xb1/0x10c
[  122.221946]  ? _atomic_dec_and_lock+0x124/0x124
[  122.221974]  ? ___ratelimit+0xfe/0x240
[  122.222020]  check_preemption_disabled+0x173/0x1b0
[  122.222060]  debug_smp_processor_id+0x17/0x20
[  122.222083]  ip6_pol_route+0x1482/0x24a0
...

I believe we can simplify this code path a bit, since we no longer
hold a read_lock and need to release it to avoid a dead lock.

By disabling BH, we make sure we'll prevent code re-entry and
rt6_get_pcpu_route()/rt6_make_pcpu_route() run on the same cpu.

Fixes: 66f5d6ce53 ("ipv6: replace rwlock with rcu and spinlock in fib6_table")
Reported-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Tested-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-08 21:09:00 -07:00
Wei Wang 81eb8447da ipv6: take care of rt6_stats
Currently, most of the rt6_stats are not hooked up correctly. As the
last part of this patch series, hook up all existing rt6_stats and add
one new stat fib_rt_uncache to indicate the number of routes in the
uncached list.
For details of the stats, please refer to the comments added in
include/net/ip6_fib.h.

Note: fib_rt_alloc and fib_rt_uncache are not guaranteed to be modified
under a lock. So atomic_t is used for them.

Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-07 21:22:58 +01:00
Wei Wang 66f5d6ce53 ipv6: replace rwlock with rcu and spinlock in fib6_table
With all the preparation work before, we are now ready to replace rwlock
with rcu and spinlock in fib6_table.
That means now all fib6_node in fib6_table are protected by rcu. And
when freeing fib6_node, call_rcu() is used to wait for the rcu grace
period before releasing the memory.
When accessing fib6_node, corresponding rcu APIs need to be used.
And all previous sessions protected by the write lock will now be
protected by the spin lock per table.
All previous sessions protected by read lock will now be protected by
rcu_read_lock().

A couple of things to note here:
1. As part of the work of replacing rwlock with rcu, the linked list of
fn->leaf now has to be rcu protected as well. So both fn->leaf and
rt->dst.rt6_next are now __rcu tagged and corresponding rcu APIs are
used when manipulating them.

2. For fn->rr_ptr, first of all, it also needs to be rcu protected now
and is tagged with __rcu and rcu APIs are used in corresponding places.
Secondly, fn->rr_ptr is changed in rt6_select() which is a reader
thread. This makes the issue a bit complicated. We think a valid
solution for it is to let rt6_select() grab the tb6_lock if it decides
to change it. As it is not in the normal operation and only happens when
there is no valid neighbor cache for the route, we think the performance
impact should be low.

3. fib6_walk_continue() has to be called with tb6_lock held even in the
route dumping related functions, e.g. inet6_dump_fib(),
fib6_tables_dump() and ipv6_route_seq_ops. It is because
fib6_walk_continue() makes modifications to the walker structure, and so
are fib6_repair_tree() and fib6_del_route(). In order to do proper
syncing between them, we need to let fib6_walk_continue() hold the lock.
We may be able to do further improvement on the way we do the tree walk
to get rid of the need for holding the spin lock. But not for now.

4. When fib6_del_route() removes a route from the tree, we no longer
mark rt->dst.rt6_next to NULL to make simultaneous reader be able to
further traverse the list with rcu. However, rt->dst.rt6_next is only
valid within this same rcu period. No one should access it later.

5. All the operation of atomic_inc(rt->rt6i_ref) is changed to be
performed before we publish this route (either by linking it to fn->leaf
or insert it in the list pointed by fn->leaf) just to be safe because as
soon as we publish the route, some read thread will be able to access it.

Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-07 21:22:58 +01:00
Wei Wang 17ecf590b3 ipv6: add key length check into rt6_select()
After rwlock is replaced with rcu and spinlock, fib6_lookup() could
potentially return an intermediate node if other thread is doing
fib6_del() on a route which is the only route on the node so that
fib6_repair_tree() will be called on this node and potentially assigns
fn->leaf to the its child's fn->leaf.

In order to detect this situation in rt6_select(), we have to check if
fn->fn_bit is consistent with the key length stored in the route. And
depending on if the fn is in the subtree or not, the key is either
rt->rt6i_dst or rt->rt6i_src.
If any inconsistency is found, that means the node no longer holds valid
routes in it. So net->ipv6.ip6_null_entry is returned.

Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-07 21:22:58 +01:00
Wei Wang 8d1040e808 ipv6: check fn->leaf before it is used
If rwlock is replaced with rcu and spinlock, it is possible that the
reader thread will see fn->leaf as NULL in the following scenarios:
1. fib6_add() is in progress and we have already inserted a new node but
not yet inserted the route.
2. fib6_del_route() is in progress and we have already set fn->leaf to
NULL but not yet freed the node because of rcu grace period.

This patch makes sure all the reader threads check fn->leaf first before
using it. And together with later patch to grab rcu_read_lock() and
rcu_dereference() fn->leaf, it makes sure reader threads are safe when
accessing fn->leaf.

Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-07 21:22:58 +01:00
Wei Wang d3843fe5fd ipv6: replace dst_hold() with dst_hold_safe() in routing code
With rwlock, it is safe to call dst_hold() in the read thread because
read thread is guaranteed to be separated from write thread.
However, after we replace rwlock with rcu, it is no longer safe to use
dst_hold(). A dst might already have been deleted but is waiting for the
rcu grace period to pass before freeing the memory when a read thread is
trying to do dst_hold(). This could potentially cause double free issue.

So this commit replaces all dst_hold() with dst_hold_safe() in all read
thread to avoid this double free issue.
And in order to make the code more compact, a new function ip6_hold_safe()
is introduced. It calls dst_hold_safe() first, and if that fails, it will
either fall back to hold and return net->ipv6.ip6_null_entry or set rt to
NULL according to the caller's need.

Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-07 21:22:58 +01:00
Wei Wang a94b9367e0 ipv6: grab rt->rt6i_ref before allocating pcpu rt
After rwlock is replaced with rcu and spinlock, ip6_pol_route() will be
called with only rcu held. That means rt6 route deletion could happen
simultaneously with rt6_make_pcpu_rt(). This could potentially cause
memory leak if rt6_release() is called right before rt6_make_pcpu_rt()
on the same route.

This patch grabs rt->rt6i_ref safely before calling rt6_make_pcpu_rt()
to make sure rt6_release() will not get triggered while
rt6_make_pcpu_rt() is in progress. And rt6_release() is called after
rt6_make_pcpu_rt() is finished.

Note: As we are incrementing rt->rt6i_ref in ip6_pol_route(), there is a
very slim chance that fib6_purge_rt() will be triggered unnecessarily
when deleting a route if ip6_pol_route() running on another thread picks
this route as well and tries to make pcpu cache for it.

Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-07 21:22:58 +01:00
Wei Wang 2b760fcf5c ipv6: hook up exception table to store dst cache
This commit makes use of the exception hash table implementation to
store dst caches created by pmtu discovery and ip redirect into the hash
table under the rt_info and no longer inserts these routes into fib6
tree.
This makes the fib6 tree only contain static configured routes and could
now be protected by rcu instead of a rw lock.
With this change, in the route lookup related functions, after finding
the rt6_info with the longest prefix, we also need to search for the
exception table before doing backtracking.
In the route delete function, if the route being deleted is not a dst
cache, deletion of this route also need to flush the whole hash table
under it. If it is a dst cache, then only delete the cached dst in the
hash table.

Note: for fib6_walk_continue() function, w->root now is always pointing
to a root node considering that fib6_prune_clones() is removed from the
code. So we add a WARN_ON() msg to make sure w->root always points to a
root node and also removed the update of w->root in fib6_repair_tree().
This is a prerequisite for later patch because we don't need to make
w->root as rcu protected when replacing rwlock with RCU.
Also, we remove all prune related variables as it is no longer used.

Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-07 21:22:57 +01:00
Wei Wang 38fbeeeecc ipv6: prepare fib6_locate() for exception table
fib6_locate() is used to find the fib6_node according to the passed in
prefix address key. It currently tries to find the fib6_node with the
exact match of the passed in key. However, when we move cached routes
into the exception table, fib6_locate() will fail to find the fib6_node
for it as the cached routes will be stored in the exception table under
the fib6_node with the longest prefix match of the cache's dst addr key.
This commit adds a new parameter to let the caller specify if it needs
exact match or longest prefix match.
Right now, all callers still does exact match when calling
fib6_locate(). It will be changed in later commit where exception table
is hooked up to store cached routes.

Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-07 21:22:57 +01:00
Wei Wang c757faa8bf ipv6: prepare fib6_age() for exception table
If all dst cache entries are stored in the exception table under the
main route, we have to go through them during fib6_age() when doing
garbage collecting.
Introduce a new function rt6_age_exception() which goes through all dst
entries in the exception table and remove those entries that are expired.
This function is called in fib6_age() so that all dst caches are also
garbage collected.

Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-07 21:22:57 +01:00
Wei Wang b16cb459d7 ipv6: prepare rt6_clean_tohost() for exception table
If we move all cached dst into the exception table under the main route,
current rt6_clean_tohost() will no longer be able to access them.
This commit makes fib6_clean_tohost() to also go through all cached
routes in exception table and removes cached gateway routes to the
passed in gateway.
This is a preparation in order to move all cached routes into the
exception table.

Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-07 21:22:57 +01:00
Wei Wang f5bbe7ee79 ipv6: prepare rt6_mtu_change() for exception table
If we move all cached dst into the exception table under the main route,
current rt6_mtu_change() will no longer be able to access them.
This commit makes rt6_mtu_change_route() function to also go through all
cached routes in the exception table under the main route and do proper
updates on the mtu.
This is a preparation in order to move all cached routes into the
exception table.

Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-07 21:22:57 +01:00
Wei Wang 60006a4825 ipv6: prepare fib6_remove_prefsrc() for exception table
After we move cached dst entries into the exception table under its
parent route, current fib6_remove_prefsrc() no longer can access them.
This commit makes fib6_remove_prefsrc() also go through all routes
in the exception table to remove the pref src.
This is a preparation patch in order to move all cached dst into the
exception table.

Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-07 21:22:57 +01:00
Wei Wang 35732d01fe ipv6: introduce a hash table to store dst cache
Add a hash table into struct rt6_info in order to store dst caches
created by pmtu discovery and ip redirect in ipv6 routing code.
APIs to add dst cache, delete dst cache, find dst cache and update
dst cache in the hash table are implemented and will be used in later
commits.
This is a preparation work to move all cache routes into the exception
table instead of getting inserted into the fib6 tree.

Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-07 21:22:57 +01:00
David S. Miller 6026e043d0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Three cases of simple overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-01 17:42:05 -07:00
Xin Long 1e2ea8ad37 ipv6: set dst.obsolete when a cached route has expired
Now it doesn't check for the cached route expiration in ipv6's
dst_ops->check(), because it trusts dst_gc that would clean the
cached route up when it's expired.

The problem is in dst_gc, it would clean the cached route only
when it's refcount is 1. If some other module (like xfrm) keeps
holding it and the module only release it when dst_ops->check()
fails.

But without checking for the cached route expiration, .check()
may always return true. Meanwhile, without releasing the cached
route, dst_gc couldn't del it. It will cause this cached route
never to expire.

This patch is to set dst.obsolete with DST_OBSOLETE_KILL in .gc
when it's expired, and check obsolete != DST_OBSOLETE_FORCE_CHK
in .check.

Note that this is even needed when ipv6 dst_gc timer is removed
one day. It would set dst.obsolete in .redirect and .update_pmtu
instead, and check for cached route expiration when getting it,
just like what ipv4 route does.

Reported-by: Jianlin Shi <jishi@redhat.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-28 15:45:04 -07:00
Wei Wang 4e587ea71b ipv6: fix sparse warning on rt6i_node
Commit c5cff8561d adds rcu grace period before freeing fib6_node. This
generates a new sparse warning on rt->rt6i_node related code:
  net/ipv6/route.c:1394:30: error: incompatible types in comparison
  expression (different address spaces)
  ./include/net/ip6_fib.h:187:14: error: incompatible types in comparison
  expression (different address spaces)

This commit adds "__rcu" tag for rt6i_node and makes sure corresponding
rcu API is used for it.
After this fix, sparse no longer generates the above warning.

Fixes: c5cff8561d ("ipv6: add rcu grace period before freeing fib6_node")
Signed-off-by: Wei Wang <weiwan@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-28 15:34:40 -07:00
Steffen Klassert 3614364527 ipv6: Fix may be used uninitialized warning in rt6_check
rt_cookie might be used uninitialized, fix this by
initializing it.

Fixes: c5cff8561d ("ipv6: add rcu grace period before freeing fib6_node")
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-25 17:05:27 -07:00
Jakub Sitnicki b673d6ccea ipv6: Use multipath hash from flow info if available
Allow our callers to influence the choice of ECMP link by honoring the
hash passed together with the flow info. This allows for special
treatment of ICMP errors which we would like to route over the same path
as the IPv6 datagram that triggered the error.

Also go through rt6_multipath_hash(), in the usual case when we aren't
dealing with an ICMP error, so that there is one central place where
multipath hash is computed.

Signed-off-by: Jakub Sitnicki <jkbs@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-24 18:21:17 -07:00
Jakub Sitnicki 956b45318a ipv6: Fold rt6_info_hash_nhsfn() into its only caller
Commit 644d0e6569 ("ipv6 Use get_hash_from_flowi6 for rt6 hash") has
turned rt6_info_hash_nhsfn() into a one-liner, so it no longer makes
sense to keep it around. Also remove the accompanying comment that has
become outdated.

Signed-off-by: Jakub Sitnicki <jkbs@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-24 18:21:17 -07:00
Jakub Sitnicki 23aebdacb0 ipv6: Compute multipath hash for ICMP errors from offending packet
When forwarding or sending out an ICMPv6 error, look at the embedded
packet that triggered the error and compute a flow hash over its
headers.

This let's us route the ICMP error together with the flow it belongs to
when multipath (ECMP) routing is in use, which in turn makes Path MTU
Discovery work in ECMP load-balanced or anycast setups (RFC 7690).

Granted, end-hosts behind the ECMP router (aka servers) need to reflect
the IPv6 Flow Label for PMTUD to work.

The code is organized to be in parallel with ipv4 stack:

  ip_multipath_l3_keys -> ip6_multipath_l3_keys
  fib_multipath_hash   -> rt6_multipath_hash

Signed-off-by: Jakub Sitnicki <jkbs@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-24 18:21:17 -07:00
Wei Wang c5cff8561d ipv6: add rcu grace period before freeing fib6_node
We currently keep rt->rt6i_node pointing to the fib6_node for the route.
And some functions make use of this pointer to dereference the fib6_node
from rt structure, e.g. rt6_check(). However, as there is neither
refcount nor rcu taken when dereferencing rt->rt6i_node, it could
potentially cause crashes as rt->rt6i_node could be set to NULL by other
CPUs when doing a route deletion.
This patch introduces an rcu grace period before freeing fib6_node and
makes sure the functions that dereference it takes rcu_read_lock().

Note: there is no "Fixes" tag because this bug was there in a very
early stage.

Signed-off-by: Wei Wang <weiwan@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-22 11:03:19 -07:00
David Ahern 4832c30d54 net: ipv6: put host and anycast routes on device with address
One nagging difference between ipv4 and ipv6 is host routes for ipv6
addresses are installed using the loopback device or VRF / L3 Master
device. e.g.,

    2001:db8:1::/120 dev veth0 proto kernel metric 256 pref medium
    local 2001:db8:1::1 dev lo table local proto kernel metric 0 pref medium

Using the loopback device is convenient -- necessary for local tx, but
has some nasty side effects, most notably setting the 'lo' device down
causes all host routes for all local IPv6 address to be removed from the
FIB and completely breaks IPv6 networking across all interfaces.

This patch puts FIB entries for IPv6 routes against the device. This
simplifies the routes in the FIB, for example by making dst->dev and
rt6i_idev->dev the same (a future patch can look at removing the device
reference taken for rt6i_idev for FIB entries).

When copies are made on FIB lookups, the cloned route has dst->dev
set to loopback (or the L3 master device). This is needed for the
local Tx of packets to local addresses.

With fib entries allocated against the real network device, the addrconf
code that reinserts host routes on admin up of 'lo' is no longer needed.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-21 10:40:17 -07:00
Arnd Bergmann 401481e060 ipv6: fix false-postive maybe-uninitialized warning
Adding a lock around one of the assignments prevents gcc from
tracking the state of the local 'fibmatch' variable, so it can no
longer prove that 'dst' is always initialized, leading to a bogus
warning:

net/ipv6/route.c: In function 'inet6_rtm_getroute':
net/ipv6/route.c:3659:2: error: 'dst' may be used uninitialized in this function [-Werror=maybe-uninitialized]

This moves the other assignment into the same lock to shut up the
warning.

Fixes: 121622dba8 ("ipv6: route: make rtm_getroute not assume rtnl is locked")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-18 10:47:21 -07:00
David S. Miller 463910e2df Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-08-15 20:23:23 -07:00
Florian Westphal e3a22b7f5c ipv6: route: set ipv6 RTM_GETROUTE to not use rtnl
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-15 17:20:55 -07:00
Florian Westphal 121622dba8 ipv6: route: make rtm_getroute not assume rtnl is locked
__dev_get_by_index assumes RTNL is held, use _rcu version instead.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-15 17:20:54 -07:00
Eric Dumazet 12d94a8049 ipv6: fix NULL dereference in ip6_route_dev_notify()
Based on a syzkaller report [1], I found that a per cpu allocation
failure in snmp6_alloc_dev() would then lead to NULL dereference in
ip6_route_dev_notify().

It seems this is a very old bug, thus no Fixes tag in this submission.

Let's add in6_dev_put_clear() helper, as we will probably use
it elsewhere (once available/present in net-next)

[1]
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 17294 Comm: syz-executor6 Not tainted 4.13.0-rc2+ #10
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff88019f456680 task.stack: ffff8801c6e58000
RIP: 0010:__read_once_size include/linux/compiler.h:250 [inline]
RIP: 0010:atomic_read arch/x86/include/asm/atomic.h:26 [inline]
RIP: 0010:refcount_sub_and_test+0x7d/0x1b0 lib/refcount.c:178
RSP: 0018:ffff8801c6e5f1b0 EFLAGS: 00010202
RAX: 0000000000000037 RBX: dffffc0000000000 RCX: ffffc90005d25000
RDX: ffff8801c6e5f218 RSI: ffffffff82342bbf RDI: 0000000000000001
RBP: ffff8801c6e5f240 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff10038dcbe37
R13: 0000000000000006 R14: 0000000000000001 R15: 00000000000001b8
FS:  00007f21e0429700(0000) GS:ffff8801dc100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001ddbc22000 CR3: 00000001d632b000 CR4: 00000000001426e0
DR0: 0000000020000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 refcount_dec_and_test+0x1a/0x20 lib/refcount.c:211
 in6_dev_put include/net/addrconf.h:335 [inline]
 ip6_route_dev_notify+0x1c9/0x4a0 net/ipv6/route.c:3732
 notifier_call_chain+0x136/0x2c0 kernel/notifier.c:93
 __raw_notifier_call_chain kernel/notifier.c:394 [inline]
 raw_notifier_call_chain+0x2d/0x40 kernel/notifier.c:401
 call_netdevice_notifiers_info+0x51/0x90 net/core/dev.c:1678
 call_netdevice_notifiers net/core/dev.c:1694 [inline]
 rollback_registered_many+0x91c/0xe80 net/core/dev.c:7107
 rollback_registered+0x1be/0x3c0 net/core/dev.c:7149
 register_netdevice+0xbcd/0xee0 net/core/dev.c:7587
 register_netdev+0x1a/0x30 net/core/dev.c:7669
 loopback_net_init+0x76/0x160 drivers/net/loopback.c:214
 ops_init+0x10a/0x570 net/core/net_namespace.c:118
 setup_net+0x313/0x710 net/core/net_namespace.c:294
 copy_net_ns+0x27c/0x580 net/core/net_namespace.c:418
 create_new_namespaces+0x425/0x880 kernel/nsproxy.c:107
 unshare_nsproxy_namespaces+0xae/0x1e0 kernel/nsproxy.c:206
 SYSC_unshare kernel/fork.c:2347 [inline]
 SyS_unshare+0x653/0xfa0 kernel/fork.c:2297
 entry_SYSCALL_64_fastpath+0x1f/0xbe
RIP: 0033:0x4512c9
RSP: 002b:00007f21e0428c08 EFLAGS: 00000216 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 0000000000718150 RCX: 00000000004512c9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000062020200
RBP: 0000000000000086 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000216 R12: 00000000004b973d
R13: 00000000ffffffff R14: 000000002001d000 R15: 00000000000002dd
Code: 50 2b 34 82 c7 00 f1 f1 f1 f1 c7 40 04 04 f2 f2 f2 c7 40 08 f3 f3
f3 f3 e8 a1 43 39 ff 4c 89 f8 48 8b 95 70 ff ff ff 48 c1 e8 03 <0f> b6
0c 18 4c 89 f8 83 e0 07 83 c0 03 38 c8 7c 08 84 c9 0f 85
RIP: __read_once_size include/linux/compiler.h:250 [inline] RSP:
ffff8801c6e5f1b0
RIP: atomic_read arch/x86/include/asm/atomic.h:26 [inline] RSP:
ffff8801c6e5f1b0
RIP: refcount_sub_and_test+0x7d/0x1b0 lib/refcount.c:178 RSP:
ffff8801c6e5f1b0
---[ end trace e441d046c6410d31 ]---

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-15 17:06:34 -07:00
Ido Schimmel fe40079995 ipv6: fib: Provide offload indication using nexthop flags
IPv6 routes currently lack nexthop flags as in IPv4. This has several
implications.

In the forwarding path, it requires us to check the carrier state of the
nexthop device and potentially ignore a linkdown route, instead of
checking for RTNH_F_LINKDOWN.

It also requires capable drivers to use the user facing IPv6-specific
route flags to provide offload indication, instead of using the nexthop
flags as in IPv4.

Add nexthop flags to IPv6 routes in the 40 bytes hole and use it to
provide offload indication instead of the RTF_OFFLOAD flag, which is
removed while it's still not part of any official kernel release.

In the near future we would like to use the field for the
RTNH_F_{LINKDOWN,DEAD} flags, but this change is more involved and might
not be ready in time for the current cycle.

Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-15 17:05:03 -07:00
Wei Wang e5645f51ba ipv6: release rt6->rt6i_idev properly during ifdown
When a dst is created by addrconf_dst_alloc() for a host route or an
anycast route, dst->dev points to loopback dev while rt6->rt6i_idev
points to a real device.
When the real device goes down, the current cleanup code only checks for
dst->dev and assumes rt6->rt6i_idev->dev is the same. This causes the
refcount leak on the real device in the above situation.
This patch makes sure to always release the refcount taken on
rt6->rt6i_idev during dst_dev_put().

Fixes: 587fea7411 ("ipv6: mark DST_NOGC and remove the operation of
dst_free()")
Reported-by: John Stultz <john.stultz@linaro.org>
Tested-by: John Stultz <john.stultz@linaro.org>
Tested-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-14 22:18:48 -07:00
Florian Westphal b97bac64a5 rtnetlink: make rtnl_register accept a flags parameter
This change allows us to later indicate to rtnetlink core that certain
doit functions should be called without acquiring rtnl_mutex.

This change should have no effect, we simply replace the last (now
unused) calcit argument with the new flag.

Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-09 16:57:38 -07:00
David S. Miller 3118e6e19d Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
The UDP offload conflict is dealt with by simply taking what is
in net-next where we have removed all of the UFO handling code
entirely.

The TCP conflict was a case of local variables in a function
being removed from both net and net-next.

In netvsc we had an assignment right next to where a missing
set of u64 stats sync object inits were added.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-09 16:28:45 -07:00
Vincent Bernat feca7d8c13 net: ipv6: avoid overhead when no custom FIB rules are installed
If the user hasn't installed any custom rules, don't go through the
whole FIB rules layer. This is pretty similar to f4530fa574 (ipv4:
Avoid overhead when no custom FIB rules are installed).

Using a micro-benchmark module [1], timing ip6_route_output() with
get_cycles(), with 40,000 routes in the main routing table, before this
patch:

    min=606 max=12911 count=627 average=1959 95th=4903 90th=3747 50th=1602 mad=821
    table=254 avgdepth=21.8 maxdepth=39
    value │                         ┊                            count
      600 │▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒                                         199
      880 │▒▒▒░░░░░░░░░░░░░░░░                                      43
     1160 │▒▒▒░░░░░░░░░░░░░░░░░░░░                                  48
     1440 │▒▒▒░░░░░░░░░░░░░░░░░░░░░░░                               43
     1720 │▒▒▒▒░░░░░░░░░░░░░░░░░░░░░░░░░░░                          59
     2000 │▒▒▒░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░                      50
     2280 │▒▒░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░                    26
     2560 │▒▒░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░                  31
     2840 │▒▒░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░               28
     3120 │▒░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░              17
     3400 │▒░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░             17
     3680 │░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░             8
     3960 │░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░           11
     4240 │░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░            6
     4520 │░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░           6
     4800 │░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░           9

After:

    min=544 max=11687 count=627 average=1776 95th=4546 90th=3585 50th=1227 mad=565
    table=254 avgdepth=21.8 maxdepth=39
    value │                         ┊                            count
      540 │▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒                                        201
      800 │▒▒▒▒▒░░░░░░░░░░░░░░░░                                    63
     1060 │▒▒▒▒▒░░░░░░░░░░░░░░░░░░░░░                               68
     1320 │▒▒▒░░░░░░░░░░░░░░░░░░░░░░░░░░                            39
     1580 │▒▒░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░                         32
     1840 │▒▒░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░                       32
     2100 │▒▒░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░                    34
     2360 │▒▒░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░                 33
     2620 │▒▒░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░               26
     2880 │▒░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░              22
     3140 │░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░              9
     3400 │░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░             8
     3660 │░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░             9
     3920 │░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░            8
     4180 │░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░           8
     4440 │░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░           8

At the frequency of the host during the bench (~ 3.7 GHz), this is
about a 100 ns difference on the median value.

A next step would be to collapse local and main tables, as in
0ddcf43d5d (ipv4: FIB Local/MAIN table collapse).

[1]: https://github.com/vincentbernat/network-lab/blob/master/lab-routes-ipv6/kbench_mod.c

Signed-off-by: Vincent Bernat <vincent@bernat.im>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-08 21:40:08 -07:00
Ido Schimmel 61e4d01e16 ipv6: fib: Add offload indication to routes
Allow user space applications to see which routes are offloaded and
which aren't by setting the RTNH_F_OFFLOAD flag when dumping them.

To be consistent with IPv4, offload indication is provided on a
per-nexthop basis.

Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-03 15:36:00 -07:00
Xin Long b91d532928 ipv6: set rt6i_protocol properly in the route when it is installed
After commit c2ed1880fd ("net: ipv6: check route protocol when
deleting routes"), ipv6 route checks rt protocol when trying to
remove a rt entry.

It introduced a side effect causing 'ip -6 route flush cache' not
to work well. When flushing caches with iproute, all route caches
get dumped from kernel then removed one by one by sending DELROUTE
requests to kernel for each cache.

The thing is iproute sends the request with the cache whose proto
is set with RTPROT_REDIRECT by rt6_fill_node() when kernel dumps
it. But in kernel the rt_cache protocol is still 0, which causes
the cache not to be matched and removed.

So the real reason is rt6i_protocol in the route is not set when
it is allocated. As David Ahern's suggestion, this patch is to
set rt6i_protocol properly in the route when it is installed and
remove the codes setting rtm_protocol according to rt6i_flags in
rt6_fill_node.

This is also an improvement to keep rt6i_protocol consistent with
rtm_protocol.

Fixes: c2ed1880fd ("net: ipv6: check route protocol when deleting routes")
Reported-by: Jianlin Shi <jishi@redhat.com>
Suggested-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-03 15:10:18 -07:00
David Ahern f06b7549b7 net: ipv6: Compare lwstate in detecting duplicate nexthops
Lennert reported a failure to add different mpls encaps in a multipath
route:

  $ ip -6 route add 1234::/16 \
        nexthop encap mpls 10 via fe80::1 dev ens3 \
        nexthop encap mpls 20 via fe80::1 dev ens3
  RTNETLINK answers: File exists

The problem is that the duplicate nexthop detection does not compare
lwtunnel configuration. Add it.

Fixes: 19e42e4515 ("ipv6: support for fib route lwtunnel encap attributes")
Signed-off-by: David Ahern <dsahern@gmail.com>
Reported-by: João Taveira Araújo <joao.taveira@gmail.com>
Reported-by: Lennert Buytenhek <buytenh@wantstofly.org>
Acked-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Tested-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-06 10:48:01 +01:00
David S. Miller b079115937 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
A set of overlapping changes in macvlan and the rocker
driver, nothing serious.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-30 12:43:08 -04:00
WANG Cong 76da070450 ipv6: only call ip6_route_dev_notify() once for NETDEV_UNREGISTER
In commit 242d3a49a2 ("ipv6: reorder ip6_route_dev_notifier after ipv6_dev_notf")
I assumed NETDEV_REGISTER and NETDEV_UNREGISTER are paired,
unfortunately, as reported by jeffy, netdev_wait_allrefs()
could rebroadcast NETDEV_UNREGISTER event until all refs are
gone.

We have to add an additional check to avoid this corner case.
For netdev_wait_allrefs() dev->reg_state is NETREG_UNREGISTERED,
for dev_change_net_namespace(), dev->reg_state is
NETREG_REGISTERED. So check for dev->reg_state != NETREG_UNREGISTERED.

Fixes: 242d3a49a2 ("ipv6: reorder ip6_route_dev_notifier after ipv6_dev_notf")
Reported-by: jeffy <jeffy.chen@rock-chips.com>
Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-22 11:06:06 -04:00
Wei Wang a4c2fd7f78 net: remove DST_NOCACHE flag
DST_NOCACHE flag check has been removed from dst_release() and
dst_hold_safe() in a previous patch because all the dst are now ref
counted properly and can be released based on refcnt only.
Looking at the rest of the DST_NOCACHE use, all of them can now be
removed or replaced with other checks.
So this patch gets rid of all the DST_NOCACHE usage and remove this flag
completely.

Signed-off-by: Wei Wang <weiwan@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-17 22:54:01 -04:00
Wei Wang b2a9c0ed75 net: remove DST_NOGC flag
Now that all the components have been changed to release dst based on
refcnt only and not depend on dst gc anymore, we can remove the
temporary flag DST_NOGC.

Note that we also need to remove the DST_NOCACHE check in dst_release()
and dst_hold_safe() because now all the dst are released based on refcnt
and behaves as DST_NOCACHE.

Signed-off-by: Wei Wang <weiwan@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-17 22:54:01 -04:00
Wei Wang db916649b5 ipv6: get rid of icmp6 dst garbage collector
icmp6 dst route is currently ref counted during creation and will be
freed by user during its call of dst_release(). So no need of a garbage
collector for it.
Remove all icmp6 dst garbage collector related code.

Signed-off-by: Wei Wang <weiwan@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-17 22:54:00 -04:00
Wei Wang 587fea7411 ipv6: mark DST_NOGC and remove the operation of dst_free()
With the previous preparation patches, we are ready to get rid of the
dst gc operation in ipv6 code and release dst based on refcnt only.
So this patch adds DST_NOGC flag for all IPv6 dst and remove the calls
to dst_free() and its related functions.
At this point, all dst created in ipv6 code do not use the dst gc
anymore and will be destroyed at the point when refcnt drops to 0.

Also, as icmp6 dst route is refcounted during creation and will be freed
by user during its call of dst_release(), there is no need to add this
dst to the icmp6 gc list as well.
Instead, we need to add it into uncached list so that when a
NETDEV_DOWN/NETDEV_UNREGISRER event comes, we can properly go through
these icmp6 dst as well and release the net device properly.

Signed-off-by: Wei Wang <weiwan@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-17 22:54:00 -04:00
Wei Wang ad65a2f056 ipv6: call dst_hold_safe() properly
Similar as ipv4, ipv6 path also needs to call dst_hold_safe() when
necessary to avoid double free issue on the dst.

Signed-off-by: Wei Wang <weiwan@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-17 22:54:00 -04:00
Wei Wang 1cfb71eeb1 ipv6: take dst->__refcnt for insertion into fib6 tree
In IPv6 routing code, struct rt6_info is created for each static route
and RTF_CACHE route and inserted into fib6 tree. In both cases, dst
ref count is not taken.
As explained in the previous patch, this leads to the need of the dst
garbage collector.

This patch holds ref count of dst before inserting the route into fib6
tree and properly releases the dst when deleting it from the fib6 tree
as a preparation in order to fully get rid of dst gc later.

Also, correct fib6_age() logic to check dst->__refcnt to be 1 to indicate
no user is referencing the dst.

And remove dst_hold() in vrf_rt6_create() as ip6_dst_alloc() already puts
dst->__refcnt to 1.

Signed-off-by: Wei Wang <weiwan@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-17 22:54:00 -04:00
Wei Wang 1dbe32525e net: use loopback dev when generating blackhole route
Existing ipv4/6_blackhole_route() code generates a blackhole route
with dst->dev pointing to the passed in dst->dev.
It is not necessary to hold reference to the passed in dst->dev
because the packets going through this route are dropped anyway.
A loopback interface is good enough so that we don't need to worry about
releasing this dst->dev when this dev is going down.

Signed-off-by: Wei Wang <weiwan@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-17 22:53:59 -04:00
David S. Miller 0ddead90b2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
The conflicts were two cases of overlapping changes in
batman-adv and the qed driver.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-15 11:59:32 -04:00
David Ahern 8397ed36b7 net: ipv6: Release route when device is unregistering
Roopa reported attempts to delete a bond device that is referenced in a
multipath route is hanging:

$ ifdown bond2    # ifupdown2 command that deletes virtual devices
unregister_netdevice: waiting for bond2 to become free. Usage count = 2

Steps to reproduce:
    echo 1 > /proc/sys/net/ipv6/conf/all/ignore_routes_with_linkdown
    ip link add dev bond12 type bond
    ip link add dev bond13 type bond
    ip addr add 2001:db8:2::0/64 dev bond12
    ip addr add 2001:db8:3::0/64 dev bond13
    ip route add 2001:db8:33::0/64 nexthop via 2001:db8:2::2 nexthop via 2001:db8:3::2
    ip link del dev bond12
    ip link del dev bond13

The root cause is the recent change to keep routes on a linkdown. Update
the check to detect when the device is unregistering and release the
route for that case.

Fixes: a1a22c1206 ("net: ipv6: Keep nexthop of multipath route on admin down")
Reported-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Acked-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-08 11:12:39 -04:00
David Ahern 9ae2872748 net: add extack arg to lwtunnel build state
Pass extack arg down to lwtunnel_build_state and the build_state callbacks.
Add messages for failures in lwtunnel_build_state, and add the extarg to
nla_parse where possible in the build_state callbacks.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-30 11:55:32 -04:00
David Ahern c255bd681d net: lwtunnel: Add extack to encap attr validation
Pass extack down to lwtunnel_valid_encap_type and
lwtunnel_valid_encap_type_attr. Add messages for unknown
or unsupported encap types.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-30 11:55:31 -04:00
Roopa Prabhu 18c3a61c42 net: ipv6: RTM_GETROUTE: return matched fib result when requested
This patch adds support to return matched fib result when RTM_F_FIB_MATCH
flag is specified in RTM_GETROUTE request. This is useful for user-space
applications/controllers wanting to query a matching route.

Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-26 14:12:51 -04:00
David Ahern d5d531cb50 net: ipv6: Add extack messages for route add failures
Add messages for non-obvious errors (e.g, no need to add text for malloc
failures or ENODEV failures). This mostly covers the annoying EINVAL errors
Some message strings violate the 80-columns but searchable strings need to
trump that rule.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-22 12:12:20 -04:00
David Ahern 333c430167 net: ipv6: Plumb extack through route add functions
Plumb extack argument down to route add functions.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-22 12:12:20 -04:00
WANG Cong 242d3a49a2 ipv6: reorder ip6_route_dev_notifier after ipv6_dev_notf
For each netns (except init_net), we initialize its null entry
in 3 places:

1) The template itself, as we use kmemdup()
2) Code around dst_init_metrics() in ip6_route_net_init()
3) ip6_route_dev_notify(), which is supposed to initialize it after
   loopback registers

Unfortunately the last one still happens in a wrong order because
we expect to initialize net->ipv6.ip6_null_entry->rt6i_idev to
net->loopback_dev's idev, thus we have to do that after we add
idev to loopback. However, this notifier has priority == 0 same as
ipv6_dev_notf, and ipv6_dev_notf is registered after
ip6_route_dev_notifier so it is called actually after
ip6_route_dev_notifier. This is similar to commit 2f460933f5
("ipv6: initialize route null entry in addrconf_init()") which
fixes init_net.

Fix it by picking a smaller priority for ip6_route_dev_notifier.
Also, we have to release the refcnt accordingly when unregistering
loopback_dev because device exit functions are called before subsys
exit functions.

Acked-by: David Ahern <dsahern@gmail.com>
Tested-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-08 17:31:24 -04:00
WANG Cong 2f460933f5 ipv6: initialize route null entry in addrconf_init()
Andrey reported a crash on init_net.ipv6.ip6_null_entry->rt6i_idev
since it is always NULL.

This is clearly wrong, we have code to initialize it to loopback_dev,
unfortunately the order is still not correct.

loopback_dev is registered very early during boot, we lose a chance
to re-initialize it in notifier. addrconf_init() is called after
ip6_route_init(), which means we have no chance to correct it.

Fix it by moving this initialization explicitly after
ipv6_add_dev(init_net.loopback_dev) in addrconf_init().

Reported-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-04 12:51:24 -04:00
David S. Miller fb796707d7 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Both conflict were simple overlapping changes.

In the kaweth case, Eric Dumazet's skb_cow() bug fix overlapped the
conversion of the driver in net-next to use in-netdev stats.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-21 20:23:53 -07:00
David Ahern 557c44be91 net: ipv6: RTF_PCPU should not be settable from userspace
Andrey reported a fault in the IPv6 route code:

kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN
Modules linked in:
CPU: 1 PID: 4035 Comm: a.out Not tainted 4.11.0-rc7+ #250
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
task: ffff880069809600 task.stack: ffff880062dc8000
RIP: 0010:ip6_rt_cache_alloc+0xa6/0x560 net/ipv6/route.c:975
RSP: 0018:ffff880062dced30 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: ffff8800670561c0 RCX: 0000000000000006
RDX: 0000000000000003 RSI: ffff880062dcfb28 RDI: 0000000000000018
RBP: ffff880062dced68 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: ffff880062dcfb28 R14: dffffc0000000000 R15: 0000000000000000
FS:  00007feebe37e7c0(0000) GS:ffff88006cb00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000205a0fe4 CR3: 000000006b5c9000 CR4: 00000000000006e0
Call Trace:
 ip6_pol_route+0x1512/0x1f20 net/ipv6/route.c:1128
 ip6_pol_route_output+0x4c/0x60 net/ipv6/route.c:1212
...

Andrey's syzkaller program passes rtmsg.rtmsg_flags with the RTF_PCPU bit
set. Flags passed to the kernel are blindly copied to the allocated
rt6_info by ip6_route_info_create making a newly inserted route appear
as though it is a per-cpu route. ip6_rt_cache_alloc sees the flag set
and expects rt->dst.from to be set - which it is not since it is not
really a per-cpu copy. The subsequent call to __ip6_dst_alloc then
generates the fault.

Fix by checking for the flag and failing with EINVAL.

Fixes: d52d3997f8 ("ipv6: Create percpu rt6_info")
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-21 13:55:33 -04:00
David Ahern c21ef3e343 net: rtnetlink: plumb extended ack to doit function
Add netlink_ext_ack arg to rtnl_doit_func. Pass extack arg to nlmsg_parse
for doit functions that call it directly.

This is the first step to using extended error reporting in rtnetlink.
>From here individual subsystems can be updated to set netlink_ext_ack as
needed.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-17 15:35:38 -04:00
Johannes Berg fceb6435e8 netlink: pass extended ACK struct to parsing functions
Pass the new extended ACK reporting struct to all of the generic
netlink parsing functions. For now, pass NULL in almost all callers
(except for some in the core.)

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-13 13:58:22 -04:00
David Ahern 4ee39733fb net: ipv6: set route type for anycast routes
Anycast routes have the RTF_ANYCAST flag set, but when dumping routes
for userspace the route type is not set to RTN_ANYCAST. Make it so.

Fixes: 58c4fb86ea ("[IPV6]: Flag RTF_ANYCAST for anycast routes")
CC: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-16 20:40:14 -07:00
David Ahern 5be083cedc net: ipv6: Remove redundant RTA_OIF in multipath routes
Dinesh reported that RTA_MULTIPATH nexthops are 8-bytes larger with IPv6
than IPv4. The recent refactoring for multipath support in netlink
messages does discriminate between non-multipath which needs the OIF
and multipath which adds a rtnexthop struct for each hop making the
RTA_OIF attribute redundant. Resolve by adding a flag to the info
function to skip the oif for multipath.

Fixes: beb1afac51 ("net: ipv6: Add support to dump multipath routes
       via RTA_MULTIPATH attribute")
Reported-by: Dinesh Dutt <ddutt@cumulusnetworks.com>
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-09 13:04:48 -08:00
WANG Cong 9d6acb3bc9 ipv6: ignore null_entry in inet6_rtm_getroute() too
Like commit 1f17e2f2c8 ("net: ipv6: ignore null_entry on route dumps"),
we need to ignore null entry in inet6_rtm_getroute() too.

Return -ENETUNREACH here to sync with IPv4 behavior, as suggested by David.

Fixes: a1a22c1206 ("net: ipv6: Keep nexthop of multipath route on admin down")
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-02 14:35:31 -08:00
WANG Cong e3330039ea ipv6: check for ip6_null_entry in __ip6_del_rt_siblings()
Andrey reported a NULL pointer deref bug in ipv6_route_ioctl()
-> ip6_route_del() -> __ip6_del_rt_siblings() code path. This is
because ip6_null_entry is returned in this path since ip6_null_entry
is kinda default for a ipv6 route table root node. Quote from
David Ahern:

 ip6_null_entry is the root of all ipv6 fib tables making it integrated
 into the table ...

We should ignore any attempt of trying to delete it, like we do in
__ip6_del_rt() path and several others.

Reported-by: Andrey Konovalov <andreyknvl@google.com>
Fixes: 0ae8133586 ("net: ipv6: Allow shorthand delete of all nexthops in multipath route")
Cc: David Ahern <dsa@cumulusnetworks.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-02 12:43:47 -08:00
Liping Zhang 3b45a4106f net: route: add missing nla_policy entry for RTA_MARK attribute
This will add stricter validating for RTA_MARK attribute.

Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-01 10:25:56 -08:00
Julian Anastasov 0dec879f63 net: use dst_confirm_neigh for UDP, RAW, ICMP, L2TP
When same struct dst_entry can be used for many different
neighbours we can not use it for pending confirmations.

The datagram protocols can use MSG_CONFIRM to confirm the
neighbour. When used with MSG_PROBE we do not reach the
code where neighbour is confirmed, so we have to do the
same slow lookup by using the dst_confirm_neigh() helper.
When MSG_PROBE is not used, ip_append_data/ip6_append_data
will set the skb flag dst_pending_confirm.

Reported-by: YueHaibing <yuehaibing@huawei.com>
Fixes: 5110effee8 ("net: Do delayed neigh confirmation.")
Fixes: f2bb4bedf3 ("ipv4: Cache output routes in fib_info nexthops.")
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-07 13:07:47 -05:00
Julian Anastasov 63fca65d08 net: add confirm_neigh method to dst_ops
Add confirm_neigh method to dst_ops and use it from IPv4 and IPv6
to lookup and confirm the neighbour. Its usage via the new helper
dst_confirm_neigh() should be restricted to MSG_PROBE users for
performance reasons.

For XFRM prefer the last tunnel address, if present. With help
from Steffen Klassert.

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Acked-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-07 13:07:46 -05:00
David Ahern 7d4d5065ec net: ipv6: Use compressed IPv6 addresses showing route replace error
ip6_print_replace_route_err logs an error if a route replace fails with
IPv6 addresses in the full format. e.g,:

IPv6: IPV6: multipath route replace failed (check consistency of installed routes): 2001:0db8:0200:0000:0000:0000:0000:0000 nexthop 2001:0db8:0001:0000:0000:0000:0000:0016 ifi 0

Change the message to dump the addresses in the compressed format.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-04 19:58:14 -05:00
David Ahern 16a16cd35e net: ipv6: Change notifications for multipath delete to RTA_MULTIPATH
If an entire multipath route is deleted using prefix and len (without any
nexthops), send a single RTM_DELROUTE notification with the full route
using RTA_MULTIPATH. This is done by generating the skb before the route
delete when all of the sibling routes are still present but sending it
after the route has been removed from the FIB. The skip_notify flag
is used to tell the lower fib code not to send notifications for the
individual nexthop routes.

If a route is deleted using RTA_MULTIPATH for any nexthops or a single
nexthop entry is deleted, then the nexthops are deleted one at a time with
notifications sent as each hop is deleted. This is necessary given that
IPv6 allows individual hops within a route to be deleted.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-04 19:58:14 -05:00
David Ahern 3b1137fe74 net: ipv6: Change notifications for multipath add to RTA_MULTIPATH
Change ip6_route_multipath_add to send one notifciation with the full
route encoded with RTA_MULTIPATH instead of a series of individual routes.
This is done by adding a skip_notify flag to the nl_info struct. The
flag is used to skip sending of the notification in the fib code that
actually inserts the route. Once the full route has been added, a
notification is generated with all nexthops.

ip6_route_multipath_add handles 3 use cases: new routes, route replace,
and route append. The multipath notification generated needs to be
consistent with the order of the nexthops and it should be consistent
with the order in a FIB dump which means the route with the first nexthop
needs to be used as the route reference. For the first 2 cases (new and
replace), a reference to the route used to send the notification is
obtained by saving the first route added. For the append case, the last
route added is used to loop back to its first sibling route which is
the first nexthop in the multipath route.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-04 19:58:14 -05:00
David Ahern beb1afac51 net: ipv6: Add support to dump multipath routes via RTA_MULTIPATH attribute
IPv6 returns multipath routes as a series of individual routes making
their display and handling by userspace different and more complicated
than IPv4, putting the burden on the user to see that a route is part of
a multipath route and internally creating a multipath route if desired
(e.g., libnl does this as of commit 29b71371e764). This patch addresses
this difference, allowing multipath routes to be returned using the
RTA_MULTIPATH attribute.

The end result is that IPv6 multipath routes can be treated and displayed
in a format similar to IPv4:

    $ ip -6 ro ls vrf red
    2001:db8:1::/120 dev eth1 proto kernel metric 256  pref medium
    2001:db8:2::/120 dev eth2 proto kernel metric 256  pref medium
    2001:db8:200::/120 metric 1024
	    nexthop via 2001:db8:1::2  dev eth1 weight 1
	    nexthop via 2001:db8:2::2  dev eth2 weight 1

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-04 19:58:14 -05:00
David Ahern 0ae8133586 net: ipv6: Allow shorthand delete of all nexthops in multipath route
IPv4 allows multipath routes to be deleted using just the prefix and
length. For example:
    $ ip ro ls vrf red
    unreachable default metric 8192
    1.1.1.0/24
        nexthop via 10.100.1.254  dev eth1 weight 1
        nexthop via 10.11.200.2  dev eth11.200 weight 1
    10.11.200.0/24 dev eth11.200 proto kernel scope link src 10.11.200.3
    10.100.1.0/24 dev eth1 proto kernel scope link src 10.100.1.3

    $ ip ro del 1.1.1.0/24 vrf red

    $ ip ro ls vrf red
    unreachable default metric 8192
    10.11.200.0/24 dev eth11.200 proto kernel scope link src 10.11.200.3
    10.100.1.0/24 dev eth1 proto kernel scope link src 10.100.1.3

The same notation does not work with IPv6 because of how multipath routes
are implemented for IPv6. For IPv6 only the first nexthop of a multipath
route is deleted if the request contains only a prefix and length. This
leads to unnecessary complexity in userspace dealing with IPv6 multipath
routes.

This patch allows all nexthops to be deleted without specifying each one
in the delete request. Internally, this is done by walking the sibling
list of the route matching the specifications given (prefix, length,
metric, protocol, etc).

    $  ip -6 ro ls vrf red
    2001:db8:1::/120 dev eth1 proto kernel metric 256  pref medium
    2001:db8:2::/120 dev eth2 proto kernel metric 256  pref medium
    2001:db8:200::/120 via 2001:db8:1::2 dev eth1 metric 1024  pref medium
    2001:db8:200::/120 via 2001:db8:2::2 dev eth2 metric 1024  pref medium
    ...

    $ ip -6 ro del vrf red 2001:db8:200::/120

    $ ip -6 ro ls vrf red
    2001:db8:1::/120 dev eth1 proto kernel metric 256  pref medium
    2001:db8:2::/120 dev eth2 proto kernel metric 256  pref medium
    ...

Because IPv6 allows individual nexthops to be deleted without deleting
the entire route, the ip6_route_multipath_del and non-multipath code
path (ip6_route_del) have to be discriminated so that all nexthops are
only deleted for the latter case. This is done by making the existing
fc_type in fib6_config a u16 and then adding a new u16 field with
fc_delete_all_nh as the first bit.

Suggested-by: Dinesh Dutt <ddutt@cumulusnetworks.com>
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-04 19:58:14 -05:00
David Ahern 94b5e0f970 net: ipv6: Set protocol to kernel for local routes
IPv6 stack does not set the protocol for local routes, so those routes show
up with proto "none":
    $ ip -6 ro ls table local
    local ::1 dev lo proto none metric 0  pref medium
    local 2100:3:: dev lo proto none metric 0  pref medium
    local 2100:3::4 dev lo proto none metric 0  pref medium
    local fe80:: dev lo proto none metric 0  pref medium
    ...

Set rt6i_protocol to RTPROT_KERNEL for consistency with IPv4. Now routes
show up with proto "kernel":
    $ ip -6 ro ls table local
    local ::1 dev lo proto kernel metric 0  pref medium
    local 2100:3:: dev lo proto kernel metric 0  pref medium
    local 2100:3::4 dev lo proto kernel metric 0  pref medium
    local fe80:: dev lo proto kernel metric 0  pref medium
    ...

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-03 16:01:44 -05:00
David Ahern 30357d7d8a lwtunnel: remove device arg to lwtunnel_build_state
Nothing about lwt state requires a device reference, so remove the
input argument.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-30 15:14:22 -05:00
David S. Miller 4e8f2fc1a5 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Two trivial overlapping changes conflicts in MPLS and mlx5.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-28 10:33:06 -05:00
David Ahern 1f17e2f2c8 net: ipv6: ignore null_entry on route dumps
lkp-robot reported a BUG:
[   10.151226] BUG: unable to handle kernel NULL pointer dereference at 00000198
[   10.152525] IP: rt6_fill_node+0x164/0x4b8
[   10.153307] *pdpt = 0000000012ee5001 *pde = 0000000000000000
[   10.153309]
[   10.154492] Oops: 0000 [#1]
[   10.154987] CPU: 0 PID: 909 Comm: netifd Not tainted 4.10.0-rc4-00722-g41e8c70ee162-dirty #10
[   10.156482] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014
[   10.158254] task: d0deb000 task.stack: d0e0c000
[   10.159059] EIP: rt6_fill_node+0x164/0x4b8
[   10.159780] EFLAGS: 00010296 CPU: 0
[   10.160404] EAX: 00000000 EBX: d10c2358 ECX: c1f7c6cc EDX: c1f6ff44
[   10.161469] ESI: 00000000 EDI: c2059900 EBP: d0e0dc4c ESP: d0e0dbe4
[   10.162534]  DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 0068
[   10.163482] CR0: 80050033 CR2: 00000198 CR3: 10d94660 CR4: 000006b0
[   10.164535] Call Trace:
[   10.164993]  ? paravirt_sched_clock+0x9/0xd
[   10.165727]  ? sched_clock+0x9/0xc
[   10.166329]  ? sched_clock_cpu+0x19/0xe9
[   10.166991]  ? lock_release+0x13e/0x36c
[   10.167652]  rt6_dump_route+0x4c/0x56
[   10.168276]  fib6_dump_node+0x1d/0x3d
[   10.168913]  fib6_walk_continue+0xab/0x167
[   10.169611]  fib6_walk+0x2a/0x40
[   10.170182]  inet6_dump_fib+0xfb/0x1e0
[   10.170855]  netlink_dump+0xcd/0x21f

This happens when the loopback device is set down and a ipv6 fib route
dump is requested.

ip6_null_entry is the root of all ipv6 fib tables making it integrated
into the table and hence passed to the ipv6 route dump code. The
null_entry route uses the loopback device for dst.dev but may not have
rt6i_idev set because of the order in which initializations are done --
ip6_route_net_init is run before addrconf_init has initialized the
loopback device. Fixing the initialization order is a much bigger problem
with no obvious solution thus far.

The BUG is triggered when the loopback is set down and the netif_running
check added by a1a22c1206 fails. The fill_node descends to checking
rt->rt6i_idev for ignore_routes_with_linkdown and since rt6i_idev is
NULL it faults.

The null_entry route should not be processed in a dump request. Catch
and ignore. This check is done in rt6_dump_route as it is the highest
place in the callchain with knowledge of both the route and the network
namespace.

Fixes: a1a22c1206("net: ipv6: Keep nexthop of multipath route on admin down")
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-26 18:39:16 -05:00
David Ahern 3b7b2b0acd net: ipv6: remove skb_reserve in getroute
Remove skb_reserve and skb_reset_mac_header from inet6_rtm_getroute. The
allocated skb is not passed through the routing engine (like it is for
IPv4) and has not since the beginning of git time.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-26 18:36:58 -05:00
David Ahern a1a22c1206 net: ipv6: Keep nexthop of multipath route on admin down
IPv6 deletes route entries associated with multipath routes on an
admin down where IPv4 does not. For example:
    $ ip ro ls vrf red
    unreachable default metric 8192
    1.1.1.0/24 metric 64
            nexthop via 10.100.1.254  dev eth1 weight 1
            nexthop via 10.100.2.254  dev eth2 weight 1
    10.100.1.0/24 dev eth1 proto kernel scope link src 10.100.1.4
    10.100.2.0/24 dev eth2 proto kernel scope link src 10.100.2.4

    $ ip -6 ro ls vrf red
    2001:db8:1::/120 dev eth1 proto kernel metric 256  pref medium
    2001:db8:2:: dev red proto none metric 0  pref medium
    2001:db8:2::/120 dev eth2 proto kernel metric 256  pref medium
    2001:db8:11::/120 via 2001:db8:1::16 dev eth1 metric 1024  pref medium
    2001:db8:11::/120 via 2001:db8:2::17 dev eth2 metric 1024  pref medium
    ...

Set link down:
    $ ip li set eth1 down

IPv4 retains the multihop route but flags eth1 route as dead:

    $ ip ro ls vrf red
    unreachable default metric 8192
    1.1.1.0/24
            nexthop via 10.100.1.16  dev eth1 weight 1 dead linkdown
            nexthop via 10.100.2.16  dev eth2 weight 1
    10.100.2.0/24 dev eth2 proto kernel scope link src 10.100.2.4

and IPv6 deletes the route as part of flushing all routes for the device:

    $ ip -6 ro ls vrf red
    2001:db8:2:: dev red proto none metric 0  pref medium
    2001:db8:2::/120 dev eth2 proto kernel metric 256  pref medium
    2001:db8:11::/120 via 2001:db8:2::17 dev eth2 metric 1024  pref medium
    ...

Worse, on admin up of the device the multipath route has to be deleted
to get this leg of the route re-added.

This patch keeps routes that are part of a multipath route if
ignore_routes_with_linkdown is set with the dead and linkdown flags
enabling consistency between IPv4 and IPv6:

    $ ip -6 ro ls vrf red
    2001:db8:2:: dev red proto none metric 0  pref medium
    2001:db8:2::/120 dev eth2 proto kernel metric 256  pref medium
    2001:db8:11::/120 via 2001:db8:1::16 dev eth1 metric 1024 dead linkdown  pref medium
    2001:db8:11::/120 via 2001:db8:2::17 dev eth2 metric 1024  pref medium
    ...

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-19 23:38:51 -05:00
David Ahern 9ed59592e3 lwtunnel: fix autoload of lwt modules
Trying to add an mpls encap route when the MPLS modules are not loaded
hangs. For example:

    CONFIG_MPLS=y
    CONFIG_NET_MPLS_GSO=m
    CONFIG_MPLS_ROUTING=m
    CONFIG_MPLS_IPTUNNEL=m

    $ ip route add 10.10.10.10/32 encap mpls 100 via inet 10.100.1.2

The ip command hangs:
root       880   826  0 21:25 pts/0    00:00:00 ip route add 10.10.10.10/32 encap mpls 100 via inet 10.100.1.2

    $ cat /proc/880/stack
    [<ffffffff81065a9b>] call_usermodehelper_exec+0xd6/0x134
    [<ffffffff81065efc>] __request_module+0x27b/0x30a
    [<ffffffff814542f6>] lwtunnel_build_state+0xe4/0x178
    [<ffffffff814aa1e4>] fib_create_info+0x47f/0xdd4
    [<ffffffff814ae451>] fib_table_insert+0x90/0x41f
    [<ffffffff814a8010>] inet_rtm_newroute+0x4b/0x52
    ...

modprobe is trying to load rtnl-lwt-MPLS:

root       881     5  0 21:25 ?        00:00:00 /sbin/modprobe -q -- rtnl-lwt-MPLS

and it hangs after loading mpls_router:

    $ cat /proc/881/stack
    [<ffffffff81441537>] rtnl_lock+0x12/0x14
    [<ffffffff8142ca2a>] register_netdevice_notifier+0x16/0x179
    [<ffffffffa0033025>] mpls_init+0x25/0x1000 [mpls_router]
    [<ffffffff81000471>] do_one_initcall+0x8e/0x13f
    [<ffffffff81119961>] do_init_module+0x5a/0x1e5
    [<ffffffff810bd070>] load_module+0x13bd/0x17d6
    ...

The problem is that lwtunnel_build_state is called with rtnl lock
held preventing mpls_init from registering.

Given the potential references held by the time lwtunnel_build_state it
can not drop the rtnl lock to the load module. So, extract the module
loading code from lwtunnel_build_state into a new function to validate
the encap type. The new function is called while converting the user
request into a fib_config which is well before any table, device or
fib entries are examined.

Fixes: 745041e2aa ("lwtunnel: autoload of lwt modules")
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-18 17:07:14 -05:00
David Ahern f8cfe2ceb1 net: ipv6: remove prefix arg to rt6_fill_node
The prefix arg to rt6_fill_node is non-0 in only 1 path - rt6_dump_route
where a user is requesting a prefix only dump. Simplify rt6_fill_node
by removing the prefix arg and moving the prefix check to rt6_dump_route.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-18 15:43:59 -05:00
David Ahern fd61c6ba31 net: ipv6: remove nowait arg to rt6_fill_node
All callers of rt6_fill_node pass 0 for nowait arg. Remove the arg and
simplify rt6_fill_node accordingly.

rt6_fill_node passes the nowait of 0 to ip6mr_get_route. Remove the
nowait arg from it as well.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-18 15:43:59 -05:00
David Ahern ea7a80858f net: lwtunnel: Handle lwtunnel_fill_encap failure
Handle failure in lwtunnel_fill_encap adding attributes to skb.

Fixes: 571e722676 ("ipv4: support for fib route lwtunnel encap attributes")
Fixes: 19e42e4515 ("ipv6: support for fib route lwtunnel encap attributes")
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-12 15:11:43 -05:00
Alexander Alemayhu 67c408cfa8 ipv6: fix typos
o s/approriate/appropriate
o s/discouvery/discovery

Signed-off-by: Alexander Alemayhu <alexander@alemayhu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-09 16:34:15 -05:00
Linus Torvalds 7c0f6ba682 Replace <asm/uaccess.h> with <linux/uaccess.h> globally
This was entirely automated, using the script by Al:

  PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
  sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
        $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-24 11:46:01 -08:00
Mantas M c2ed1880fd net: ipv6: check route protocol when deleting routes
The protocol field is checked when deleting IPv4 routes, but ignored for
IPv6, which causes problems with routing daemons accidentally deleting
externally set routes (observed by multiple bird6 users).

This can be verified using `ip -6 route del <prefix> proto something`.

Signed-off-by: Mantas Mikulėnas <grawity@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-17 21:37:06 -05:00
Erik Nordmark 96d5822c1d ipv6: Allow IPv4-mapped address as next-hop
Made kernel accept IPv6 routes with IPv4-mapped address as next-hop.

It is possible to configure IP interfaces with IPv4-mapped addresses, and
one can add IPv6 routes for IPv4-mapped destinations/prefixes, yet prior
to this fix the kernel returned an EINVAL when attempting to add an IPv6
route with an IPv4-mapped address as a nexthop/gateway.

RFC 4798 (a proposed standard RFC) uses IPv4-mapped addresses as nexthops,
thus in order to support that type of address configuration the kernel
needs to allow IPv4-mapped addresses as nexthops.

Signed-off-by: Erik Nordmark <nordmark@arista.com>
Signed-off-by: Bob Gilligan <gilligan@arista.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-05 14:52:05 -05:00
Erik Nordmark adc176c547 ipv6 addrconf: Implemented enhanced DAD (RFC7527)
Implemented RFC7527 Enhanced DAD.
IPv6 duplicate address detection can fail if there is some temporary
loopback of Ethernet frames. RFC7527 solves this by including a random
nonce in the NS messages used for DAD, and if an NS is received with the
same nonce it is assumed to be a looped back DAD probe and is ignored.
RFC7527 is enabled by default. Can be disabled by setting both of
conf/{all,interface}/enhanced_dad to zero.

Signed-off-by: Erik Nordmark <nordmark@arista.com>
Signed-off-by: Bob Gilligan <gilligan@arista.com>
Reviewed-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-03 23:21:37 -05:00
David S. Miller bb598c1b8c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Several cases of bug fixes in 'net' overlapping other changes in
'net-next-.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-15 10:54:36 -05:00
Maciej Żenczykowski fb56be83e4 net-ipv6: on device mtu change do not add mtu to mtu-less routes
Routes can specify an mtu explicitly or inherit the mtu from
the underlying device - this inheritance is implemented in
dst->ops->mtu handlers ip6_mtu() and ip6_blackhole_mtu().

Currently changing the mtu of a device adds mtu explicitly
to routes using that device.

ie.
  # ip link set dev lo mtu 65536
  # ip -6 route add local 2000::1 dev lo
  # ip -6 route get 2000::1
  local 2000::1 dev lo  table local  src ...  metric 1024  pref medium

  # ip link set dev lo mtu 65535
  # ip -6 route get 2000::1
  local 2000::1 dev lo  table local  src ...  metric 1024  mtu 65535 pref medium

  # ip link set dev lo mtu 65536
  # ip -6 route get 2000::1
  local 2000::1 dev lo  table local  src ...  metric 1024  mtu 65536 pref medium

  # ip -6 route del local 2000::1

After this patch the route entry no longer changes unless it already has an mtu.
There is no need: this inheritance is already done in ip6_mtu()

  # ip link set dev lo mtu 65536
  # ip -6 route add local 2000::1 dev lo
  # ip -6 route add local 2000::2 dev lo mtu 2000
  # ip -6 route get 2000::1; ip -6 route get 2000::2
  local 2000::1 dev lo  table local  src ...  metric 1024  pref medium
  local 2000::2 dev lo  table local  src ...  metric 1024  mtu 2000 pref medium

  # ip link set dev lo mtu 65535
  # ip -6 route get 2000::1; ip -6 route get 2000::2
  local 2000::1 dev lo  table local  src ...  metric 1024  pref medium
  local 2000::2 dev lo  table local  src ...  metric 1024  mtu 2000 pref medium

  # ip link set dev lo mtu 1501
  # ip -6 route get 2000::1; ip -6 route get 2000::2
  local 2000::1 dev lo  table local  src ...  metric 1024  pref medium
  local 2000::2 dev lo  table local  src ...  metric 1024  mtu 1501 pref medium

  # ip link set dev lo mtu 65536
  # ip -6 route get 2000::1; ip -6 route get 2000::2
  local 2000::1 dev lo  table local  src ...  metric 1024  pref medium
  local 2000::2 dev lo  table local  src ...  metric 1024  mtu 65536 pref medium

  # ip -6 route del local 2000::1
  # ip -6 route del local 2000::2

This is desirable because changing device mtu and then resetting it
to the previous value shouldn't change the user visible routing table.

Signed-off-by: Maciej Żenczykowski <maze@google.com>
CC: Eric Dumazet <edumazet@google.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-09 13:19:32 -05:00
Lorenzo Colitti e2d118a1cb net: inet: Support UID-based routing in IP protocols.
- Use the UID in routing lookups made by protocol connect() and
  sendmsg() functions.
- Make sure that routing lookups triggered by incoming packets
  (e.g., Path MTU discovery) take the UID of the socket into
  account.
- For packets not associated with a userspace socket, (e.g., ping
  replies) use UID 0 inside the user namespace corresponding to
  the network namespace the socket belongs to. This allows
  all namespaces to apply routing and iptables rules to
  kernel-originated traffic in that namespaces by matching UID 0.
  This is better than using the UID of the kernel socket that is
  sending the traffic, because the UID of kernel sockets created
  at namespace creation time (e.g., the per-processor ICMP and
  TCP sockets) is the UID of the user that created the socket,
  which might not be mapped in the namespace.

Tested: compiles allnoconfig, allyesconfig, allmodconfig
Tested: https://android-review.googlesource.com/253302
Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-04 14:45:23 -04:00
Lorenzo Colitti 622ec2c9d5 net: core: add UID to flows, rules, and routes
- Define a new FIB rule attributes, FRA_UID_RANGE, to describe a
  range of UIDs.
- Define a RTA_UID attribute for per-UID route lookups and dumps.
- Support passing these attributes to and from userspace via
  rtnetlink. The value INVALID_UID indicates no UID was
  specified.
- Add a UID field to the flow structures.

Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-04 14:45:23 -04:00
Xin Long 19bda36c42 ipv6: add mtu lock check in __ip6_rt_update_pmtu
Prior to this patch, ipv6 didn't do mtu lock check in ip6_update_pmtu.
It leaded to that mtu lock doesn't really work when receiving the pkt
of ICMPV6_PKT_TOOBIG.

This patch is to add mtu lock check in __ip6_rt_update_pmtu just as ipv4
did in __ip_rt_update_pmtu.

Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-31 14:24:24 -04:00
David Ahern d5d32e4b76 net: ipv6: Do not consider link state for nexthop validation
Similar to IPv4, do not consider link state when validating next hops.

Currently, if the link is down default routes can fail to insert:
 $ ip -6 ro add vrf blue default via 2100:2::64 dev eth2
 RTNETLINK answers: No route to host

With this patch the command succeeds.

Fixes: 8c14586fc3 ("net: ipv6: Use passed in table for nexthop lookups")
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-27 16:33:12 -04:00
David Ahern 830218c1ad net: ipv6: Fix processing of RAs in presence of VRF
rt6_add_route_info and rt6_add_dflt_router were updated to pull the FIB
table from the device index, but the corresponding rt6_get_route_info
and rt6_get_dflt_router functions were not leading to the failure to
process RA's:

    ICMPv6: RA: ndisc_router_discovery failed to add default route

Fix the 'get' functions by using the table id associated with the
device when applicable.

Also, now that default routes can be added to tables other than the
default table, rt6_purge_dflt_routers needs to be updated as well to
look at all tables. To handle that efficiently, add a flag to the table
denoting if it is has a default route via RA.

Fixes: ca254490c8 ("net: Add VRF support to IPv6 stack")
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-27 16:30:52 -04:00
David S. Miller b50afd203a Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Three sets of overlapping changes.  Nothing serious.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-02 22:20:41 -04:00
Nikolay Aleksandrov 2cf750704b ipmr, ip6mr: fix scheduling while atomic and a deadlock with ipmr_get_route
Since the commit below the ipmr/ip6mr rtnl_unicast() code uses the portid
instead of the previous dst_pid which was copied from in_skb's portid.
Since the skb is new the portid is 0 at that point so the packets are sent
to the kernel and we get scheduling while atomic or a deadlock (depending
on where it happens) by trying to acquire rtnl two times.
Also since this is RTM_GETROUTE, it can be triggered by a normal user.

Here's the sleeping while atomic trace:
[ 7858.212557] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:620
[ 7858.212748] in_atomic(): 1, irqs_disabled(): 0, pid: 0, name: swapper/0
[ 7858.212881] 2 locks held by swapper/0/0:
[ 7858.213013]  #0:  (((&mrt->ipmr_expire_timer))){+.-...}, at: [<ffffffff810fbbf5>] call_timer_fn+0x5/0x350
[ 7858.213422]  #1:  (mfc_unres_lock){+.....}, at: [<ffffffff8161e005>] ipmr_expire_process+0x25/0x130
[ 7858.213807] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.8.0-rc7+ #179
[ 7858.213934] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014
[ 7858.214108]  0000000000000000 ffff88005b403c50 ffffffff813a7804 0000000000000000
[ 7858.214412]  ffffffff81a1338e ffff88005b403c78 ffffffff810a4a72 ffffffff81a1338e
[ 7858.214716]  000000000000026c 0000000000000000 ffff88005b403ca8 ffffffff810a4b9f
[ 7858.215251] Call Trace:
[ 7858.215412]  <IRQ>  [<ffffffff813a7804>] dump_stack+0x85/0xc1
[ 7858.215662]  [<ffffffff810a4a72>] ___might_sleep+0x192/0x250
[ 7858.215868]  [<ffffffff810a4b9f>] __might_sleep+0x6f/0x100
[ 7858.216072]  [<ffffffff8165bea3>] mutex_lock_nested+0x33/0x4d0
[ 7858.216279]  [<ffffffff815a7a5f>] ? netlink_lookup+0x25f/0x460
[ 7858.216487]  [<ffffffff8157474b>] rtnetlink_rcv+0x1b/0x40
[ 7858.216687]  [<ffffffff815a9a0c>] netlink_unicast+0x19c/0x260
[ 7858.216900]  [<ffffffff81573c70>] rtnl_unicast+0x20/0x30
[ 7858.217128]  [<ffffffff8161cd39>] ipmr_destroy_unres+0xa9/0xf0
[ 7858.217351]  [<ffffffff8161e06f>] ipmr_expire_process+0x8f/0x130
[ 7858.217581]  [<ffffffff8161dfe0>] ? ipmr_net_init+0x180/0x180
[ 7858.217785]  [<ffffffff8161dfe0>] ? ipmr_net_init+0x180/0x180
[ 7858.217990]  [<ffffffff810fbc95>] call_timer_fn+0xa5/0x350
[ 7858.218192]  [<ffffffff810fbbf5>] ? call_timer_fn+0x5/0x350
[ 7858.218415]  [<ffffffff8161dfe0>] ? ipmr_net_init+0x180/0x180
[ 7858.218656]  [<ffffffff810fde10>] run_timer_softirq+0x260/0x640
[ 7858.218865]  [<ffffffff8166379b>] ? __do_softirq+0xbb/0x54f
[ 7858.219068]  [<ffffffff816637c8>] __do_softirq+0xe8/0x54f
[ 7858.219269]  [<ffffffff8107a948>] irq_exit+0xb8/0xc0
[ 7858.219463]  [<ffffffff81663452>] smp_apic_timer_interrupt+0x42/0x50
[ 7858.219678]  [<ffffffff816625bc>] apic_timer_interrupt+0x8c/0xa0
[ 7858.219897]  <EOI>  [<ffffffff81055f16>] ? native_safe_halt+0x6/0x10
[ 7858.220165]  [<ffffffff810d64dd>] ? trace_hardirqs_on+0xd/0x10
[ 7858.220373]  [<ffffffff810298e3>] default_idle+0x23/0x190
[ 7858.220574]  [<ffffffff8102a20f>] arch_cpu_idle+0xf/0x20
[ 7858.220790]  [<ffffffff810c9f8c>] default_idle_call+0x4c/0x60
[ 7858.221016]  [<ffffffff810ca33b>] cpu_startup_entry+0x39b/0x4d0
[ 7858.221257]  [<ffffffff8164f995>] rest_init+0x135/0x140
[ 7858.221469]  [<ffffffff81f83014>] start_kernel+0x50e/0x51b
[ 7858.221670]  [<ffffffff81f82120>] ? early_idt_handler_array+0x120/0x120
[ 7858.221894]  [<ffffffff81f8243f>] x86_64_start_reservations+0x2a/0x2c
[ 7858.222113]  [<ffffffff81f8257c>] x86_64_start_kernel+0x13b/0x14a

Fixes: 2942e90050 ("[RTNETLINK]: Use rtnl_unicast() for rtnetlink unicasts")
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-25 23:41:39 -04:00
David S. Miller d6989d4bbe Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-09-23 06:46:57 -04:00
Vincent Bernat a435a07f91 net: ipv6: fallback to full lookup if table lookup is unsuitable
Commit 8c14586fc3 ("net: ipv6: Use passed in table for nexthop
lookups") introduced a regression: insertion of an IPv6 route in a table
not containing the appropriate connected route for the gateway but which
contained a non-connected route (like a default gateway) fails while it
was previously working:

    $ ip link add eth0 type dummy
    $ ip link set up dev eth0
    $ ip addr add 2001:db8::1/64 dev eth0
    $ ip route add ::/0 via 2001:db8::5 dev eth0 table 20
    $ ip route add 2001:db8:cafe::1/128 via 2001:db8::6 dev eth0 table 20
    RTNETLINK answers: No route to host
    $ ip -6 route show table 20
    default via 2001:db8::5 dev eth0  metric 1024  pref medium

After this patch, we get:

    $ ip route add 2001:db8:cafe::1/128 via 2001:db8::6 dev eth0 table 20
    $ ip -6 route show table 20
    2001:db8:cafe::1 via 2001:db8::6 dev eth0  metric 1024  pref medium
    default via 2001:db8::5 dev eth0  metric 1024  pref medium

Fixes: 8c14586fc3 ("net: ipv6: Use passed in table for nexthop lookups")
Signed-off-by: Vincent Bernat <vincent@bernat.im>
Acked-by: David Ahern <dsa@cumulusnetworks.com>
Tested-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-20 03:28:29 -04:00
Mahesh Bandewar d409b84768 ipv6: Export p6_route_input_lookup symbol
Make ip6_route_input_lookup available outside of ipv6 the module
similar to ip_route_input_noref in the IPv4 world.

Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-19 01:25:22 -04:00