Commit Graph

103 Commits

Author SHA1 Message Date
David Ahern 4f04256c98 net: vrf: Drop local rtable and rt6_info
The VRF cached rtable and rt6_info for local traffic are no longer
needed and actually prevent local traffic through enslaved devices.
Remove them.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-13 20:05:12 -07:00
David Ahern 53b9483565 net: vrf: Add extack messages for newlink failures
Add extack error messages for failure paths creating vrf devices. Once
extack support is added to iproute2, we go from the unhelpful:
    $  ip li add foobar type vrf
    RTNETLINK answers: Invalid argument

to:
    $ ip li add foobar type vrf
    Error: VRF table id is missing

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-07 15:16:33 -07:00
Nikolay Aleksandrov f630c38ef0 vrf: fix bug_on triggered by rx when destroying a vrf
When destroying a VRF device we cleanup the slaves in its ndo_uninit()
function, but that causes packets to be switched (skb->dev == vrf being
destroyed) even though we're pass the point where the VRF should be
receiving any packets while it is being dismantled. This causes a BUG_ON
to trigger if we have raw sockets (trace below).
The reason is that the inetdev of the VRF has been destroyed but we're
still sending packets up the stack with it, so let's free the slaves in
the dellink callback as David Ahern suggested.

Note that this fix doesn't prevent packets from going up when the VRF
device is admin down.

[   35.631371] ------------[ cut here ]------------
[   35.631603] kernel BUG at net/ipv4/fib_frontend.c:285!
[   35.631854] invalid opcode: 0000 [#1] SMP
[   35.631977] Modules linked in:
[   35.632081] CPU: 2 PID: 22 Comm: ksoftirqd/2 Not tainted 4.12.0-rc7+ #45
[   35.632247] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014
[   35.632477] task: ffff88005ad68000 task.stack: ffff88005ad64000
[   35.632632] RIP: 0010:fib_compute_spec_dst+0xfc/0x1ee
[   35.632769] RSP: 0018:ffff88005ad67978 EFLAGS: 00010202
[   35.632910] RAX: 0000000000000001 RBX: ffff880059a7f200 RCX: 0000000000000000
[   35.633084] RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffff82274af0
[   35.633256] RBP: ffff88005ad679f8 R08: 000000000001ef70 R09: 0000000000000046
[   35.633430] R10: ffff88005ad679f8 R11: ffff880037731cb0 R12: 0000000000000001
[   35.633603] R13: ffff8800599e3000 R14: 0000000000000000 R15: ffff8800599cb852
[   35.634114] FS:  0000000000000000(0000) GS:ffff88005d900000(0000) knlGS:0000000000000000
[   35.634306] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   35.634456] CR2: 00007f3563227095 CR3: 000000000201d000 CR4: 00000000000406e0
[   35.634632] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   35.634865] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   35.635055] Call Trace:
[   35.635271]  ? __lock_acquire+0xf0d/0x1117
[   35.635522]  ipv4_pktinfo_prepare+0x82/0x151
[   35.635831]  raw_rcv_skb+0x17/0x3c
[   35.636062]  raw_rcv+0xe5/0xf7
[   35.636287]  raw_local_deliver+0x169/0x1d9
[   35.636534]  ip_local_deliver_finish+0x87/0x1c4
[   35.636820]  ip_local_deliver+0x63/0x7f
[   35.637058]  ip_rcv_finish+0x340/0x3a1
[   35.637295]  ip_rcv+0x314/0x34a
[   35.637525]  __netif_receive_skb_core+0x49f/0x7c5
[   35.637780]  ? lock_acquire+0x13f/0x1d7
[   35.638018]  ? lock_acquire+0x15e/0x1d7
[   35.638259]  __netif_receive_skb+0x1e/0x94
[   35.638502]  ? __netif_receive_skb+0x1e/0x94
[   35.638748]  netif_receive_skb_internal+0x74/0x300
[   35.639002]  ? dev_gro_receive+0x2ed/0x411
[   35.639246]  ? lock_is_held_type+0xc4/0xd2
[   35.639491]  napi_gro_receive+0x105/0x1a0
[   35.639736]  receive_buf+0xc32/0xc74
[   35.639965]  ? detach_buf+0x67/0x153
[   35.640201]  ? virtqueue_get_buf_ctx+0x120/0x176
[   35.640453]  virtnet_poll+0x128/0x1c5
[   35.640690]  net_rx_action+0x103/0x343
[   35.640932]  __do_softirq+0x1c7/0x4b7
[   35.641171]  run_ksoftirqd+0x23/0x5c
[   35.641403]  smpboot_thread_fn+0x24f/0x26d
[   35.641646]  ? sort_range+0x22/0x22
[   35.641878]  kthread+0x129/0x131
[   35.642104]  ? __list_add+0x31/0x31
[   35.642335]  ? __list_add+0x31/0x31
[   35.642568]  ret_from_fork+0x2a/0x40
[   35.642804] Code: 05 bd 87 a3 00 01 e8 1f ef 98 ff 4d 85 f6 48 c7 c7 f0 4a 27 82 41 0f 94 c4 31 c9 31 d2 41 0f b6 f4 e8 04 71 a1 ff 45 84 e4 74 02 <0f> 0b 0f b7 93 c4 00 00 00 4d 8b a5 80 05 00 00 48 03 93 d0 00
[   35.644342] RIP: fib_compute_spec_dst+0xfc/0x1ee RSP: ffff88005ad67978

Fixes: 193125dbd8 ("net: Introduce VRF device driver")
Reported-by: Chris Cormier <chriscormier@cumulusnetworks.com>
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-06 16:46:07 +01:00
Matthias Schiffer a8b8a889e3 net: add netlink_ext_ack argument to rtnl_link_ops.validate
Add support for extended error reporting.

Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-26 23:13:22 -04:00
Matthias Schiffer 7a3f4a1851 net: add netlink_ext_ack argument to rtnl_link_ops.newlink
Add support for extended error reporting.

Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-26 23:13:21 -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 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
Johannes Berg d58ff35122 networking: make skb_push & __skb_push return void pointers
It seems like a historic accident that these return unsigned char *,
and in many places that means casts are required, more often than not.

Make these functions return void * and remove all the casts across
the tree, adding a (u8 *) cast only where the unsigned char pointer
was used directly, all done with the following spatch:

    @@
    expression SKB, LEN;
    typedef u8;
    identifier fn = { skb_push, __skb_push, skb_push_rcsum };
    @@
    - *(fn(SKB, LEN))
    + *(u8 *)fn(SKB, LEN)

    @@
    expression E, SKB, LEN;
    identifier fn = { skb_push, __skb_push, skb_push_rcsum };
    type T;
    @@
    - E = ((T *)(fn(SKB, LEN)))
    + E = fn(SKB, LEN)

    @@
    expression SKB, LEN;
    identifier fn = { skb_push, __skb_push, skb_push_rcsum };
    @@
    - fn(SKB, LEN)[0]
    + *(u8 *)fn(SKB, LEN)

Note that the last part there converts from push(...)[0] to the
more idiomatic *(u8 *)push(...).

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-16 11:48:40 -04:00
David Ahern 097d3c9508 net: vrf: Make add_fib_rules per network namespace flag
Commit 1aa6c4f6b8 ("net: vrf: Add l3mdev rules on first device create")
adds the l3mdev FIB rule the first time a VRF device is created. However,
it only creates the rule once and only in the namespace the first device
is created - which may not be init_net. Fix by using the net_generic
capability to make the add_fib_rules flag per network namespace.

Fixes: 1aa6c4f6b8 ("net: vrf: Add l3mdev rules on first device create")
Reported-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-08 19:27:42 -04:00
David S. Miller cf124db566 net: Fix inconsistent teardown and release of private netdev state.
Network devices can allocate reasources and private memory using
netdev_ops->ndo_init().  However, the release of these resources
can occur in one of two different places.

Either netdev_ops->ndo_uninit() or netdev->destructor().

The decision of which operation frees the resources depends upon
whether it is necessary for all netdev refs to be released before it
is safe to perform the freeing.

netdev_ops->ndo_uninit() presumably can occur right after the
NETDEV_UNREGISTER notifier completes and the unicast and multicast
address lists are flushed.

netdev->destructor(), on the other hand, does not run until the
netdev references all go away.

Further complicating the situation is that netdev->destructor()
almost universally does also a free_netdev().

This creates a problem for the logic in register_netdevice().
Because all callers of register_netdevice() manage the freeing
of the netdev, and invoke free_netdev(dev) if register_netdevice()
fails.

If netdev_ops->ndo_init() succeeds, but something else fails inside
of register_netdevice(), it does call ndo_ops->ndo_uninit().  But
it is not able to invoke netdev->destructor().

This is because netdev->destructor() will do a free_netdev() and
then the caller of register_netdevice() will do the same.

However, this means that the resources that would normally be released
by netdev->destructor() will not be.

Over the years drivers have added local hacks to deal with this, by
invoking their destructor parts by hand when register_netdevice()
fails.

Many drivers do not try to deal with this, and instead we have leaks.

Let's close this hole by formalizing the distinction between what
private things need to be freed up by netdev->destructor() and whether
the driver needs unregister_netdevice() to perform the free_netdev().

netdev->priv_destructor() performs all actions to free up the private
resources that used to be freed by netdev->destructor(), except for
free_netdev().

netdev->needs_free_netdev is a boolean that indicates whether
free_netdev() should be done at the end of unregister_netdevice().

Now, register_netdevice() can sanely release all resources after
ndo_ops->ndo_init() succeeds, by invoking both ndo_ops->ndo_uninit()
and netdev->priv_destructor().

And at the end of unregister_netdevice(), we invoke
netdev->priv_destructor() and optionally call free_netdev().

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-07 15:53:24 -04:00
Gao Feng 1a4a5bf52a driver: vrf: Fix one possible use-after-free issue
The current codes only deal with the case that the skb is dropped, it
may meet one use-after-free issue when NF_HOOK returns 0 that means
the skb is stolen by one netfilter rule or hook.

When one netfilter rule or hook stoles the skb and return NF_STOLEN,
it means the skb is taken by the rule, and other modules should not
touch this skb ever. Maybe the skb is queued or freed directly by the
rule.

Now uses the nf_hook instead of NF_HOOK to get the result of netfilter,
and check the return value of nf_hook. Only when its value equals 1, it
means the skb could go ahead. Or reset the skb as NULL.

BTW, because vrf_rcv_finish is empty function, so needn't invoke it
even though nf_hook returns 1. But we need to modify vrf_rcv_finish
to deal with the NF_STOLEN case.

There are two cases when skb is stolen.
1. The skb is stolen and freed directly.
   There is nothing we need to do, and vrf_rcv_finish isn't invoked.
2. The skb is queued and reinjected again.
   The vrf_rcv_finish would be invoked as okfn, so need to free the
   skb in it.

Signed-off-by: Gao Feng <gfree.wind@vip.163.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-11 12:13:11 -04:00
David Ahern 26d31ac11f net: vrf: Do not allow looback to be moved to a VRF
Moving the loopback into a VRF breaks networking for the default VRF.
Since the VRF device is the loopback for VRF domains, there is no
reason to move the loopback. Given the repercussions, block attempts
to set lo into a VRF.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Reviewed-by: Greg Rose <gvrose8192@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-27 16:49:43 -04:00
David S. Miller 7b9f6da175 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
A function in kernel/bpf/syscall.c which got a bug fix in 'net'
was moved to kernel/bpf/verifier.c in 'net-next'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-20 10:35:33 -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
David Ahern 426c87caa2 net: vrf: Fix setting NLM_F_EXCL flag when adding l3mdev rule
Only need 1 l3mdev FIB rule. Fix setting NLM_F_EXCL in the nlmsghdr.

Fixes: 1aa6c4f6b8 ("net: vrf: Add l3mdev rules on first device create")
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-17 13:27:54 -04:00
David S. Miller 16ae1f2236 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/broadcom/genet/bcmmii.c
	drivers/net/hyperv/netvsc.c
	kernel/bpf/hashtab.c

Almost entirely overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-23 16:41:27 -07:00
David Ahern a9ec54d1b0 net: vrf: performance improvements for IPv6
The VRF driver allows users to implement device based features for an
entire domain. For example, a qdisc or netfilter rules can be attached
to a VRF device or tcpdump can be used to view packets for all devices
in the L3 domain.

The device-based features come with a performance penalty, most
notably in the Tx path. The VRF driver uses the l3mdev_l3_out hook
to switch the dst on an skb to its private dst. This allows the skb
to traverse the xmit stack with the device set to the VRF device
which in turn enables the netfilter and qdisc features. The VRF
driver then performs the FIB lookup again and reinserts the packet.

This patch avoids the redirect for IPv6 packets if a qdisc has not
been attached to a VRF device which is the default config. In this
case the netfilter hooks and network taps are directly traversed in
the l3mdev_l3_out handler. If a qdisc is attached to a VRF device,
then the redirect using the vrf dst is done.

Additional overhead is removed by only checking packet taps if a
socket is open on the device (vrf_dev->ptype_all list is not empty).
Packet sockets bound to any device will still get a copy of the
packet via the real ingress or egress interface.

The end result of this change is a decrease in the overhead of VRF
for the default, baseline case (ie., no netfilter rules, no packet
sockets, no qdisc) from a +3% improvement for UDP which has a lookup
per packet (VRF being better than no l3mdev) to ~2% loss for TCP_CRR
which connects a socket for each request-response.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-22 11:19:48 -07:00
David Ahern dcdd43c41e net: vrf: performance improvements for IPv4
The VRF driver allows users to implement device based features for an
entire domain. For example, a qdisc or netfilter rules can be attached
to a VRF device or tcpdump can be used to view packets for all devices
in the L3 domain.

The device-based features come with a performance penalty, most
notably in the Tx path. The VRF driver uses the l3mdev_l3_out hook
to switch the dst on an skb to its private dst. This allows the skb
to traverse the xmit stack with the device set to the VRF device
which in turn enables the netfilter and qdisc features. The VRF
driver then performs the FIB lookup again and reinserts the packet.

This patch avoids the redirect for IPv4 packets if a qdisc has not
been attached to a VRF device which is the default config. In this
case the netfilter hooks and network taps are directly traversed in
the l3mdev_l3_out handler. If a qdisc is attached to a VRF device,
then the redirect using the vrf dst is done.

Additional overhead is removed by only checking packet taps if a
socket is open on the device (vrf_dev->ptype_all list is not empty).
Packet sockets bound to any device will still get a copy of the
packet via the real ingress or egress interface.

The end result of this change is a decrease in the overhead of VRF
for the default, baseline case (ie., no netfilter rules, no packet
sockets, no qdisc) to ~3% for UDP which has a lookup per packet and
< 1% overhead for connected sockets that leverage early demux and
avoid FIB lookups.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-22 11:19:48 -07:00
David Ahern 3dc857f0e8 net: vrf: Reset rt6i_idev in local dst after put
The VRF driver takes a reference to the inet6_dev on the VRF device for
its rt6_local dst when handling local traffic through the VRF device as
a loopback. When the device is deleted the driver does a put on the idev
but does not reset rt6i_idev in the rt6_info struct. When the dst is
destroyed, dst_destroy calls ip6_dst_destroy which does a second put for
what is essentially the same reference causing it to be prematurely freed.
Reset rt6i_idev after the put in the vrf driver.

Fixes: b4869aa2f8 ("net: vrf: ipv6 support for local traffic to
                       local addresses")
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-21 17:50:20 -07:00
Ido Schimmel fdeea7be88 net: vrf: Set slave's private flag before linking
Allow listeners of the subsequent CHANGEUPPER notification to retrieve
the VRF's table ID by calling l3mdev_fib_table() with the slave netdev.
Without this change, the netdev won't be considered an L3 slave and the
function would return 0.

This is consistent with other master device such as bridge and bond that
set the slave's private flag before linking. It also makes
do_vrf_{add,del}_slave() symmetric.

Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Acked-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-16 10:18:34 -07:00
David Ahern f7887d40e5 vrf: Fix use-after-free in vrf_xmit
KASAN detected a use-after-free:

[  269.467067] BUG: KASAN: use-after-free in vrf_xmit+0x7f1/0x827 [vrf] at addr ffff8800350a21c0
[  269.467067] Read of size 4 by task ssh/1879
[  269.467067] CPU: 1 PID: 1879 Comm: ssh Not tainted 4.10.0+ #249
[  269.467067] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014
[  269.467067] Call Trace:
[  269.467067]  dump_stack+0x81/0xb6
[  269.467067]  kasan_object_err+0x21/0x78
[  269.467067]  kasan_report+0x2f7/0x450
[  269.467067]  ? vrf_xmit+0x7f1/0x827 [vrf]
[  269.467067]  ? ip_output+0xa4/0xdb
[  269.467067]  __asan_load4+0x6b/0x6d
[  269.467067]  vrf_xmit+0x7f1/0x827 [vrf]
...

Which corresponds to the skb access after xmit handling. Fix by saving
skb->len and using the saved value to update stats.

Fixes: 193125dbd8 ("net: Introduce VRF device driver")
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-08 23:10:02 -08:00
Julian Anastasov c16ec18599 net: rename dst_neigh_output back to neigh_output
After the dst->pending_confirm flag was removed, we do not
need anymore to provide dst arg to dst_neigh_output.
So, rename it to neigh_output as before commit 5110effee8
("net: Do delayed neigh confirmation.").

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-11 21:25:18 -05:00
Julian Anastasov 4ff0620354 net: add dst_pending_confirm flag to skbuff
Add new skbuff flag to allow protocols to confirm neighbour.
When same struct dst_entry can be used for many different
neighbours we can not use it for pending confirmations.

Add sock_confirm_neigh() helper to confirm the neighbour and
use it for IPv4, IPv6 and VRF before dst_neigh_output.

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 13:07:46 -05:00
David S. Miller 02ac5d1487 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Two AF_* families adding entries to the lockdep tables
at the same time.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-11 14:43:39 -05:00
David Ahern 24c63bbc18 net: vrf: do not allow table id 0
Frank reported that vrf devices can be created with a table id of 0.
This breaks many of the run time table id checks and should not be
allowed. Detect this condition at create time and fail with EINVAL.

Fixes: 193125dbd8 ("net: Introduce VRF device driver")
Reported-by: Frank Kellermann <frank.kellermann@atos.net>
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-11 10:04:01 -05:00
David Ahern 7a18c5b9fb net: ipv4: Fix multipath selection with vrf
fib_select_path does not call fib_select_multipath if oif is set in the
flow struct. For VRF use cases oif is always set, so multipath route
selection is bypassed. Use the FLOWI_FLAG_SKIP_NH_OIF to skip the oif
check similar to what is done in fib_table_lookup.

Add saddr and proto to the flow struct for the fib lookup done by the
VRF driver to better match hash computation for a flow.

Fixes: 613d09b30f ("net: Use VRF device index for lookups on TX")
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-11 09:59:55 -05:00
stephen hemminger bc1f44709c net: make ndo_get_stats64 a void function
The network device operation for reading statistics is only called
in one place, and it ignores the return value. Having a structure
return value is potentially confusing because some future driver could
incorrectly assume that the return value was used.

Fix all drivers with ndo_get_stats64 to have a void function.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-08 17:51:44 -05:00
David Ahern 926d93a33e net: vrf: Add missing Rx counters
The move from rx-handler to L3 receive handler inadvertantly dropped the
rx counters. Restore them.

Fixes: 74b20582ac ("net: l3mdev: Add hook in ip and ipv6")
Reported-by: Dinesh Dutt <ddutt@cumulusnetworks.com>
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-03 18:51:40 -05:00
David Ahern eb63ecc170 net: vrf: Drop conntrack data after pass through VRF device on Tx
Locally originated traffic in a VRF fails in the presence of a POSTROUTING
rule. For example,

    $ iptables -t nat -A POSTROUTING -s 11.1.1.0/24  -j MASQUERADE
    $ ping -I red -c1 11.1.1.3
    ping: Warning: source address might be selected on device other than red.
    PING 11.1.1.3 (11.1.1.3) from 11.1.1.2 red: 56(84) bytes of data.
    ping: sendmsg: Operation not permitted

Worse, the above causes random corruption resulting in a panic in random
places (I have not seen a consistent backtrace).

Call nf_reset to drop the conntrack info following the pass through the
VRF device.  The nf_reset is needed on Tx but not Rx because of the order
in which NF_HOOK's are hit: on Rx the VRF device is after the real ingress
device and on Tx it is is before the real egress device. Connection
tracking should be tied to the real egress device and not the VRF device.

Fixes: 8f58336d3f ("net: Add ethernet header for pass through VRF device")
Fixes: 35402e3136 ("net: Add IPv6 support to VRF device")
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-17 10:47:31 -05:00
David Ahern a0f37efa82 net: vrf: Fix NAT within a VRF
Connection tracking with VRF is broken because the pass through the VRF
device drops the connection tracking info. Removing the call to nf_reset
allows DNAT and MASQUERADE to work across interfaces within a VRF.

Fixes: 73e20b761a ("net: vrf: Add support for PREROUTING rules on vrf device")
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-17 10:45:57 -05:00
David Ahern e58e415968 net: Enable support for VRF with ipv4 multicast
Enable support for IPv4 multicast:
- similar to unicast the flow struct is updated to L3 master device
  if relevant prior to calling fib_rules_lookup. The table id is saved
  to the lookup arg so the rule action for ipmr can return the table
  associated with the device.

- ip_mr_forward needs to check for master device mismatch as well
  since the skb->dev is set to it

- allow multicast address on VRF device for Rx by checking for the
  daddr in the VRF device as well as the original ingress device

- on Tx need to drop to __mkroute_output when FIB lookup fails for
  multicast destination address.

- if CONFIG_IP_MROUTE_MULTIPLE_TABLES is enabled VRF driver creates
  IPMR FIB rules on first device create similar to FIB rules. In
  addition the VRF driver does not divert IPv4 multicast packets:
  it breaks on Tx since the fib lookup fails on the mcast address.

With this patch, ipmr forwarding and local rx/tx work.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-01 11:54:26 -04:00
David Ahern a04a480d43 net: Require exact match for TCP socket lookups if dif is l3mdev
Currently, socket lookups for l3mdev (vrf) use cases can match a socket
that is bound to a port but not a device (ie., a global socket). If the
sysctl tcp_l3mdev_accept is not set this leads to ack packets going out
based on the main table even though the packet came in from an L3 domain.
The end result is that the connection does not establish creating
confusion for users since the service is running and a socket shows in
ss output. Fix by requiring an exact dif to sk_bound_dev_if match if the
skb came through an interface enslaved to an l3mdev device and the
tcp_l3mdev_accept is not set.

skb's through an l3mdev interface are marked by setting a flag in
inet{6}_skb_parm. The IPv6 variant is already set; this patch adds the
flag for IPv4. Using an skb flag avoids a device lookup on the dif. The
flag is set in the VRF driver using the IP{6}CB macros. For IPv4, the
inet_skb_parm struct is moved in the cb per commit 971f10eca1, so the
match function in the TCP stack needs to use TCP_SKB_CB. For IPv6, the
move is done after the socket lookup, so IP6CB is used.

The flags field in inet_skb_parm struct needs to be increased to add
another flag. There is currently a 1-byte hole following the flags,
so it can be expanded to u16 without increasing the size of the struct.

Fixes: 193125dbd8 ("net: Introduce VRF device driver")
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-17 10:17:05 -04:00
David Ahern e1fb9d0389 net: vrf: Remove RT_FL_TOS
No longer used after d66f6c0a8f ("net: ipv4: Remove l3mdev_get_saddr")

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-17 10:05:05 -04:00
David Ahern c71ad3d45a net: flow: Remove FLOWI_FLAG_L3MDEV_SRC flag
No longer used

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-10 23:12:53 -07:00
David Ahern afb460fe0e net: l3mdev: remove get_rtable method
No longer used

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-10 23:12:53 -07:00
David Ahern 8a966fc016 net: ipv6: Remove l3mdev_get_saddr6
No longer needed

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-10 23:12:53 -07:00
David Ahern d66f6c0a8f net: ipv4: Remove l3mdev_get_saddr
No longer needed

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-10 23:12:53 -07:00
David Ahern 4c1feac58e net: vrf: Flip IPv6 output path from FIB lookup hook to out hook
Flip the IPv6 output path to use the l3mdev tx out hook. The VRF dst
is not returned on the first FIB lookup. Instead, the dst on the
skb is switched at the beginning of the IPv6 output processing to
send the packet to the VRF driver on xmit.

Link scope addresses (linklocal and multicast) need special handling:
specifically the oif the flow struct can not be changed because we
want the lookup tied to the enslaved interface. ie., the source address
and the returned route MUST point to the interface scope passed in.
Convert the existing vrf_get_rt6_dst to handle only link scope addresses.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-10 23:12:52 -07:00
David Ahern ebfc102c56 net: vrf: Flip IPv4 output path from FIB lookup hook to out hook
Flip the IPv4 output path to use the l3mdev tx out hook. The VRF dst
is not returned on the first FIB lookup. Instead, the dst on the
skb is switched at the beginning of the IPv4 output processing to
send the packet to the VRF driver on xmit.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-10 23:12:52 -07:00
David Ahern 73e20b761a net: vrf: Add support for PREROUTING rules on vrf device
Add support for PREROUTING rules with skb->dev set to the vrf device.
INPUT rules are already allowed. Provides symmetry with the output path
which allows POSTROUTING rules.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-05 11:50:05 -07:00
David Ahern 0d240e7811 net: vrf: Implement get_saddr for IPv6
IPv6 source address selection needs to consider the real egress route.
Similar to IPv4 implement a get_saddr6 method which is called if
source address has not been set.  The get_saddr6 method does a full
lookup which means pulling a route from the VRF FIB table and properly
considering linklocal/multicast destination addresses. Lookup failures
(eg., unreachable) then cause the source address selection to fail
which gets propagated back to the caller.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-17 21:25:29 -07:00
David Ahern 810e530bfa net: vrf: Switch dst dev to loopback on device delete
Attempting to delete a VRF device with a socket bound to it can stall:

  unregister_netdevice: waiting for red to become free. Usage count = 1

The unregister is waiting for the dst to be released and with it
references to the vrf device. Similar to dst_ifdown switch the dst
dev to loopback on delete for all of the dst's for the vrf device
and release the references to the vrf device.

Fixes: 193125dbd8 ("net: Introduce VRF device driver")
Fixes: 35402e3136 ("net: Add IPv6 support to VRF device")
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-15 21:39:59 -07:00
David Ahern 7889681f4a net: vrf: Update flags and features settings
1. Default VRF devices to not having a qdisc (IFF_NO_QUEUE). Users
   can add one as desired.

2. Disable adding a VLAN to a VRF device.

3. Enable offloads and hardware features similar to other logical
   devices (e.g., dummy, veth)

Change provides a significant boost in TCP stream Tx performance,
from ~2,700 Mbps to ~18,100 Mbps and makes throughput close to the
performance without a VRF (18,500 Mbps). netperf TCP_STREAM benchmark
using qemu with virtio+vhost for the NICs

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-15 14:03:48 -07:00
David Ahern 9ff7438460 net: vrf: Handle ipv6 multicast and link-local addresses
IPv6 multicast and link-local addresses require special handling by the
VRF driver:
1. Rather than using the VRF device index and full FIB lookups,
   packets to/from these addresses should use direct FIB lookups based on
   the VRF device table.

2. fail sends/receives on a VRF device to/from a multicast address
   (e.g, make ping6 ff02::1%<vrf> fail)

3. move the setting of the flow oif to the first dst lookup and revert
   the change in icmpv6_echo_reply made in ca254490c8 ("net: Add VRF
   support to IPv6 stack"). Linklocal/mcast addresses require use of the
   skb->dev.

With this change connections into and out of a VRF enslaved device work
for multicast and link-local addresses work (icmp, tcp, and udp)
e.g.,

1. packets into VM with VRF config:
    ping6 -c3 fe80::e0:f9ff:fe1c:b974%br1
    ping6 -c3 ff02::1%br1

    ssh -6 fe80::e0:f9ff:fe1c:b974%br1

2. packets going out a VRF enslaved device:
    ping6 -c3 fe80::18f8:83ff:fe4b:7a2e%eth1
    ping6 -c3 ff02::1%eth1
    ssh -6 root@fe80::18f8:83ff:fe4b:7a2e%eth1

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-15 12:34:34 -07:00
David Ahern cd2a9e62c8 net: l3mdev: Remove const from flowi6 arg to get_rt6_dst
Allow drivers to pass flow arg to functions where the arg is not const
and allow the driver to make updates as needed (eg., setting oif).

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-15 12:34:34 -07:00
David Ahern e434863718 net: vrf: Fix crash when IPv6 is disabled at boot time
Frank Kellermann reported a kernel crash with 4.5.0 when IPv6 is
disabled at boot using the kernel option ipv6.disable=1. Using
current net-next with the boot option:

$ ip link add red type vrf table 1001

Generates:
[12210.919584] BUG: unable to handle kernel NULL pointer dereference at 0000000000000748
[12210.921341] IP: [<ffffffff814b30e3>] fib6_get_table+0x2c/0x5a
[12210.922537] PGD b79e3067 PUD bb32b067 PMD 0
[12210.923479] Oops: 0000 [#1] SMP
[12210.924001] Modules linked in: ipvlan 8021q garp mrp stp llc
[12210.925130] CPU: 3 PID: 1177 Comm: ip Not tainted 4.7.0-rc1+ #235
[12210.926168] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014
[12210.928065] task: ffff8800b9ac4640 ti: ffff8800bacac000 task.ti: ffff8800bacac000
[12210.929328] RIP: 0010:[<ffffffff814b30e3>]  [<ffffffff814b30e3>] fib6_get_table+0x2c/0x5a
[12210.930697] RSP: 0018:ffff8800bacaf888  EFLAGS: 00010202
[12210.931563] RAX: 0000000000000748 RBX: ffffffff81a9e280 RCX: ffff8800b9ac4e28
[12210.932688] RDX: 00000000000000e9 RSI: 0000000000000002 RDI: 0000000000000286
[12210.933820] RBP: ffff8800bacaf898 R08: ffff8800b9ac4df0 R09: 000000000052001b
[12210.934941] R10: 00000000657c0000 R11: 000000000000c649 R12: 00000000000003e9
[12210.936032] R13: 00000000000003e9 R14: ffff8800bace7800 R15: ffff8800bb3ec000
[12210.937103] FS:  00007faa1766c700(0000) GS:ffff88013ac00000(0000) knlGS:0000000000000000
[12210.938321] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[12210.939166] CR2: 0000000000000748 CR3: 00000000b79d6000 CR4: 00000000000406e0
[12210.940278] Stack:
[12210.940603]  ffff8800bb3ec000 ffffffff81a9e280 ffff8800bacaf8c8 ffffffff814b3135
[12210.941818]  ffff8800bb3ec000 ffffffff81a9e280 ffffffff81a9e280 ffff8800bace7800
[12210.943040]  ffff8800bacaf8f0 ffffffff81397c88 ffff8800bb3ec000 ffffffff81a9e280
[12210.944288] Call Trace:
[12210.944688]  [<ffffffff814b3135>] fib6_new_table+0x24/0x8a
[12210.945516]  [<ffffffff81397c88>] vrf_dev_init+0xd4/0x162
[12210.946328]  [<ffffffff814091e1>] register_netdevice+0x100/0x396
[12210.947209]  [<ffffffff8139823d>] vrf_newlink+0x40/0xb3
[12210.948001]  [<ffffffff814187f0>] rtnl_newlink+0x5d3/0x6d5
...

The problem above is due to the fact that the fib hash table is not
allocated when IPv6 is disabled at boot.

As for the VRF driver it should not do any IPv6 initializations if IPv6
is disabled, so it needs to know if IPv6 is disabled at boot. The disable
parameter is private to the IPv6 module, so provide an accessor for
modules to determine if IPv6 was disabled at boot time.

Fixes: 35402e3136 ("net: Add IPv6 support to VRF device")
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-09 23:34:42 -07:00
Eric Dumazet 78e7a2ae87 net: vrf: call netdev_lockdep_set_classes()
In case a qdisc is used on a vrf device, we need to use different
lockdep classes to avoid false positives.

Use the new netdev_lockdep_set_classes() generic helper.

Reported-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Tested-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-09 13:28:37 -07:00
David Ahern 1aa6c4f6b8 net: vrf: Add l3mdev rules on first device create
Add l3mdev rule per address family when the first VRF device is
created. The rules are installed with a default preference of 1000.
Users can replace the default rule as desired.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-08 11:36:02 -07:00
David Ahern b4869aa2f8 net: vrf: ipv6 support for local traffic to local addresses
Add support for locally originated traffic to VRF-local IPv6 addresses.
Similar to IPv4 a local dst is set on the skb and the packet is
reinserted with a call to netif_rx. With this patch, ping, tcp and udp
packets to a local IPv6 address are successfully routed:

    $ ip addr show dev eth1
    4: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master red state UP group default qlen 1000
        link/ether 02:e0:f9:1c:b9:74 brd ff:ff:ff:ff:ff:ff
        inet 10.100.1.1/24 brd 10.100.1.255 scope global eth1
           valid_lft forever preferred_lft forever
        inet6 2100:1::1/120 scope global
           valid_lft forever preferred_lft forever
        inet6 fe80::e0:f9ff:fe1c:b974/64 scope link
           valid_lft forever preferred_lft forever

    $ ping6 -c1 -I red 2100:1::1
    ping6: Warning: source address might be selected on device other than red.
    PING 2100:1::1(2100:1::1) from 2100:1::1 red: 56 data bytes
    64 bytes from 2100:1::1: icmp_seq=1 ttl=64 time=0.098 ms

ip6_input is exported so the VRF driver can use it for the dst input
function. The dst_alloc function for IPv4 defaults to setting the input and
output functions; IPv6's does not. VRF does not need to duplicate the Rx path
so just export the ipv6 input function.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-08 00:25:38 -07:00
David Ahern afe80a4998 net: vrf: ipv4 support for local traffic to local addresses
Add support for locally originated traffic to VRF-local addresses. If
destination device for an skb is the loopback or VRF device then set
its dst to a local version of the VRF cached dst_entry and call netif_rx
to insert the packet onto the rx queue - similar to what is done for
loopback. This patch handles IPv4 support; follow on patch handles IPv6.

With this patch, ping, tcp and udp packets to a local IPv4 address are
successfully routed:

    $ ip addr show dev eth1
    4: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master red state UP group default qlen 1000
        link/ether 02:e0:f9:1c:b9:74 brd ff:ff:ff:ff:ff:ff
        inet 10.100.1.1/24 brd 10.100.1.255 scope global eth1
           valid_lft forever preferred_lft forever
        inet6 2100:1::1/120 scope global
           valid_lft forever preferred_lft forever
        inet6 fe80::e0:f9ff:fe1c:b974/64 scope link
           valid_lft forever preferred_lft forever

    $ ping -c1 -I red 10.100.1.1
    ping: Warning: source address might be selected on device other than red.
    PING 10.100.1.1 (10.100.1.1) from 10.100.1.1 red: 56(84) bytes of data.
    64 bytes from 10.100.1.1: icmp_seq=1 ttl=64 time=0.057 ms

This patch also enables use of IPv4 loopback address on the VRF device:
    $ ip addr add dev red 127.0.0.1/8

    $ ping -c1 -I red 127.0.0.1
    PING 127.0.0.1 (127.0.0.1) from 127.0.0.1 red: 56(84) bytes of data.
    64 bytes from 127.0.0.1: icmp_seq=1 ttl=64 time=0.058 ms

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-08 00:25:38 -07:00