linux.git/include/net, branch v4.3-rc4

af_unix: Convert the unix_sk macro to an inline function for type safety

2015-09-29T20:47:07+00:00

As suggested by Eric Dumazet this change replaces the
#define with a static inline function to enjoy
complaints by the compiler when misusing the API.

Signed-off-by: Aaron Conole 
Signed-off-by: David S. Miller

ipv4: send arp replies to the correct tunnel

2015-09-24T21:31:36+00:00

When using ip lwtunnels, the additional data for xmit (basically, the actual
tunnel to use) are carried in ip_tunnel_info either in dst->lwtstate or in
metadata dst. When replying to ARP requests, we need to send the reply to
the same tunnel the request came from. This means we need to construct
proper metadata dst for ARP replies.

We could perform another route lookup to get a dst entry with the correct
lwtstate. However, this won't always ensure that the outgoing tunnel is the
same as the incoming one, and it won't work anyway for IPv4 duplicate
address detection.

The only thing to do is to "reverse" the ip_tunnel_info.

Signed-off-by: Jiri Benc 
Acked-by: Thomas Graf 
Signed-off-by: David S. Miller

tcp/dccp: fix timewait races in timer handling

2015-09-21T23:32:29+00:00

When creating a timewait socket, we need to arm the timer before
allowing other cpus to find it. The signal allowing cpus to find
the socket is setting tw_refcnt to non zero value.

As we set tw_refcnt in __inet_twsk_hashdance(), we therefore need to
call inet_twsk_schedule() first.

This also means we need to remove tw_refcnt changes from
inet_twsk_schedule() and let the caller handle it.

Note that because we use mod_timer_pinned(), we have the guarantee
the timer wont expire before we set tw_refcnt as we run in BH context.

To make things more readable I introduced inet_twsk_reschedule() helper.

When rearming the timer, we can use mod_timer_pending() to make sure
we do not rearm a canceled timer.

Note: This bug can possibly trigger if packets of a flow can hit
multiple cpus. This does not normally happen, unless flow steering
is broken somehow. This explains this bug was spotted ~5 months after
its introduction.

A similar fix is needed for SYN_RECV sockets in reqsk_queue_hash_req(),
but will be provided in a separate patch for proper tracking.

Fixes: 789f558cfb36 ("tcp/dccp: get rid of central timewait timer")
Signed-off-by: Eric Dumazet 
Reported-by: Ying Cai 
Signed-off-by: David S. Miller

ip6tunnel: make rx/tx bytes counters consistent

2015-09-21T05:36:42+00:00

Like the previous patch, which fixes ipv4 tunnels, here is the ipv6 part.

Before the patch, the external ipv6 header + gre header were included on
tx.

After the patch:
$ ping -c1 192.168.6.121 ; ip -s l ls dev ip6gre1
PING 192.168.6.121 (192.168.6.121) 56(84) bytes of data.
64 bytes from 192.168.6.121: icmp_req=1 ttl=64 time=1.92 ms

--- 192.168.6.121 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 1.923/1.923/1.923/0.000 ms
7: ip6gre1@NONE:  mtu 1440 qdisc noqueue state UNKNOWN mode DEFAULT group default
    link/gre6 20:01:06:60:30:08:c1:c3:00:00:00:00:00:00:01:23 peer 20:01:06:60:30:08:c1:c3:00:00:00:00:00:00:01:21
    RX: bytes  packets  errors  dropped overrun mcast
    84         1        0       0       0       0
    TX: bytes  packets  errors  dropped carrier collsns
    84         1        0       0       0       0
$ ping -c1 192.168.1.121 ; ip -s l ls dev ip6tnl1
PING 192.168.1.121 (192.168.1.121) 56(84) bytes of data.
64 bytes from 192.168.1.121: icmp_req=1 ttl=64 time=2.28 ms

--- 192.168.1.121 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 2.288/2.288/2.288/0.000 ms
8: ip6tnl1@NONE:  mtu 1452 qdisc noqueue state UNKNOWN mode DEFAULT group default
    link/tunnel6 2001:660:3008:c1c3::123 peer 2001:660:3008:c1c3::121
    RX: bytes  packets  errors  dropped overrun mcast
    84         1        0       0       0       0
    TX: bytes  packets  errors  dropped carrier collsns
    84         1        0       0       0       0

Signed-off-by: Nicolas Dichtel 
Signed-off-by: David S. Miller

net: Fix behaviour of unreachable, blackhole and prohibit routes

2015-09-21T04:45:08+00:00

Man page of ip-route(8) says following about route types:

  unreachable - these destinations are unreachable.  Packets are dis‐
  carded and the ICMP message host unreachable is generated.  The local
  senders get an EHOSTUNREACH error.

  blackhole - these destinations are unreachable.  Packets are dis‐
  carded silently.  The local senders get an EINVAL error.

  prohibit - these destinations are unreachable.  Packets are discarded
  and the ICMP message communication administratively prohibited is
  generated.  The local senders get an EACCES error.

In the inet6 address family, this was correct, except the local senders
got ENETUNREACH error instead of EHOSTUNREACH in case of unreachable route.
In the inet address family, all three route types generated ICMP message
net unreachable, and the local senders got ENETUNREACH error.

In both address families all three route types now behave consistently
with documentation.

Signed-off-by: Nikola Forró 
Signed-off-by: David S. Miller

net: Fix vti use case with oif in dst lookups

2015-09-17T23:36:34+00:00

Steffen reported that the recent change to add oif to dst lookups breaks
the VTI use case. The problem is that with the oif set in the flow struct
the comparison to the nh_oif is triggered. Fix by splitting the
FLOWI_FLAG_VRFSRC into 2 flags -- one that triggers the vrf device cache
bypass (FLOWI_FLAG_VRFSRC) and another telling the lookup to not compare
nh oif (FLOWI_FLAG_SKIP_NH_OIF).

Fixes: 42a7b32b73d6 ("xfrm: Add oif to dst lookups")

Signed-off-by: David Ahern 
Acked-by: Steffen Klassert 
Signed-off-by: David S. Miller

ipv6: include NLM_F_REPLACE in route replace notifications

2015-09-17T22:00:27+00:00

This patch adds NLM_F_REPLACE flag to ipv6 route replace notifications.
This makes nlm_flags in ipv6 replace notifications consistent
with ipv4.

Signed-off-by: Roopa Prabhu 
Acked-by: Nicolas Dichtel 
Reviewed-by: Michal Kubecek 
Signed-off-by: David S. Miller

ipv6: Replace spinlock with seqlock and rcu in ip6_tunnel

2015-09-15T21:53:05+00:00

This patch uses a seqlock to ensure consistency between idst->dst and
idst->cookie.  It also makes dst freeing from fib tree to undergo a
rcu grace period.

Signed-off-by: Martin KaFai Lau 
Signed-off-by: David S. Miller

ipv6: Fix dst_entry refcnt bugs in ip6_tunnel

2015-09-15T21:53:05+00:00

Problems in the current dst_entry cache in the ip6_tunnel:

1. ip6_tnl_dst_set is racy.  There is no lock to protect it:
   - One major problem is that the dst refcnt gets messed up. F.e.
     the same dst_cache can be released multiple times and then
     triggering the infamous dst refcnt < 0 warning message.
   - Another issue is the inconsistency between dst_cache and
     dst_cookie.

   It can be reproduced by adding and removing the ip6gre tunnel
   while running a super_netperf TCP_CRR test.

2. ip6_tnl_dst_get does not take the dst refcnt before returning
   the dst.

This patch:
1. Create a percpu dst_entry cache in ip6_tnl
2. Use a spinlock to protect the dst_cache operations
3. ip6_tnl_dst_get always takes the dst refcnt before returning

Signed-off-by: Martin KaFai Lau 
Signed-off-by: David S. Miller

ipv6: Rename the dst_cache helper functions in ip6_tunnel

2015-09-15T21:53:04+00:00

It is a prep work to fix the dst_entry refcnt bugs in
ip6_tunnel.

This patch rename:
1. ip6_tnl_dst_check() to ip6_tnl_dst_get() to better
   reflect that it will take a dst refcnt in the next patch.
2. ip6_tnl_dst_store() to ip6_tnl_dst_set() to have a more
   conventional name matching with ip6_tnl_dst_get().

Signed-off-by: Martin KaFai Lau 
Signed-off-by: David S. Miller