linux-stable.git/net/ipv6, branch v3.10.90

net/ipv6: Correct PIM6 mrt_lock handling

2015-10-01T10:07:38+00:00

[ Upstream commit 25b4a44c19c83d98e8c0807a7ede07c1f28eab8b ]

In the IPv6 multicast routing code the mrt_lock was not being released
correctly in the MFC iterator, as a result adding or deleting a MIF would
cause a hang because the mrt_lock could not be acquired.

This fix is a copy of the code for the IPv4 case and ensures that the lock
is released correctly.

Signed-off-by: Richard Laing 
Acked-by: Cong Wang 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv6: fix exthdrs offload registration in out_rt path

2015-10-01T10:07:38+00:00

[ Upstream commit e41b0bedba0293b9e1e8d1e8ed553104b9693656 ]

We previously register IPPROTO_ROUTING offload under inet6_add_offload(),
but in error path, we try to unregister it with inet_del_offload(). This
doesn't seem correct, it should actually be inet6_del_offload(), also
ipv6_exthdrs_offload_exit() from that commit seems rather incorrect (it
also uses rthdr_offload twice), but it got removed entirely later on.

Fixes: 3336288a9fea ("ipv6: Switch to using new offload infrastructure.")
Signed-off-by: Daniel Borkmann 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ip6_gre: release cached dst on tunnel removal

2015-10-01T10:07:37+00:00

[ Upstream commit d4257295ba1b389c693b79de857a96e4b7cd8ac0 ]

When a tunnel is deleted, the cached dst entry should be released.

This problem may prevent the removal of a netns (seen with a x-netns IPv6
gre tunnel):
  unregister_netdevice: waiting for lo to become free. Usage count = 3

CC: Dmitry Kozlov 
Fixes: c12b395a4664 ("gre: Support GRE over IPv6")
Signed-off-by: huaibin Wang 
Signed-off-by: Nicolas Dichtel 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv6: lock socket in ip6_datagram_connect()

2015-10-01T10:07:37+00:00

[ Upstream commit 03645a11a570d52e70631838cb786eb4253eb463 ]

ip6_datagram_connect() is doing a lot of socket changes without
socket being locked.

This looks wrong, at least for udp_lib_rehash() which could corrupt
lists because of concurrent udp_sk(sk)->udp_portaddr_hash accesses.

Signed-off-by: Eric Dumazet 
Acked-by: Herbert Xu 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv6: Make MLD packets to only be processed locally

2015-10-01T10:07:34+00:00

[ Upstream commit 4c938d22c88a9ddccc8c55a85e0430e9c62b1ac5 ]

Before commit daad151263cf ("ipv6: Make ipv6_is_mld() inline and use it
from ip6_mc_input().") MLD packets were only processed locally. After the
change, a copy of MLD packet goes through ip6_mr_input, causing
MRT6MSG_NOCACHE message to be generated to user space.

Make MLD packet only processed locally.

Fixes: daad151263cf ("ipv6: Make ipv6_is_mld() inline and use it from ip6_mc_input().")
Signed-off-by: Hermin Anggawijaya 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv6: update ip6_rt_last_gc every time GC is run

2015-07-04T02:48:09+00:00

commit 49a18d86f66d33a20144ecb5a34bba0d1856b260 upstream.

As pointed out by Eric Dumazet, net->ipv6.ip6_rt_last_gc should
hold the last time garbage collector was run so that we should
update it whenever fib6_run_gc() calls fib6_clean_all(), not only
if we got there from ip6_dst_gc().

Signed-off-by: Michal Kubecek 
Signed-off-by: David S. Miller 
Cc: Konstantin Khlebnikov 
Signed-off-by: Greg Kroah-Hartman

ipv6: prevent fib6_run_gc() contention

2015-07-04T02:48:09+00:00

commit 2ac3ac8f86f2fe065d746d9a9abaca867adec577 upstream.

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

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

Resolve this by replacing special value ~0UL of expire parameter
to fib6_run_gc() by explicit "force" parameter to choose between
spin_lock_bh() and spin_trylock_bh() and call fib6_run_gc() with
force=false if gc_thresh is reached but not max_size.

Signed-off-by: Michal Kubecek 
Signed-off-by: David S. Miller 
Cc: Konstantin Khlebnikov 
Signed-off-by: Greg Kroah-Hartman

xfrm: Increase the garbage collector threshold

2015-07-04T02:48:09+00:00

commit eeb1b73378b560e00ff1da2ef09fed9254f4e128 upstream.

With the removal of the routing cache, we lost the
option to tweak the garbage collector threshold
along with the maximum routing cache size. So git
commit 703fb94ec ("xfrm: Fix the gc threshold value
for ipv4") moved back to a static threshold.

It turned out that the current threshold before we
start garbage collecting is much to small for some
workloads, so increase it from 1024 to 32768. This
means that we start the garbage collector if we have
more than 32768 dst entries in the system and refuse
new allocations if we are above 65536.

Reported-by: Wolfgang Walter 
Signed-off-by: Steffen Klassert 
Cc: Stephen Hemminger 
Signed-off-by: Greg Kroah-Hartman

udp: fix behavior of wrong checksums

2015-06-22T23:55:51+00:00

[ Upstream commit beb39db59d14990e401e235faf66a6b9b31240b0 ]

We have two problems in UDP stack related to bogus checksums :

1) We return -EAGAIN to application even if receive queue is not empty.
   This breaks applications using edge trigger epoll()

2) Under UDP flood, we can loop forever without yielding to other
   processes, potentially hanging the host, especially on non SMP.

This patch is an attempt to make things better.

We might in the future add extra support for rt applications
wanting to better control time spent doing a recv() in a hostile
environment. For example we could validate checksums before queuing
packets in socket receive queue.

Signed-off-by: Eric Dumazet 
Cc: Willem de Bruijn 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv6: Don't reduce hop limit for an interface

2015-04-29T08:33:55+00:00

[ Upstream commit 6fd99094de2b83d1d4c8457f2c83483b2828e75a ]

A local route may have a lower hop_limit set than global routes do.

RFC 3756, Section 4.2.7, "Parameter Spoofing"

>   1.  The attacker includes a Current Hop Limit of one or another small
>       number which the attacker knows will cause legitimate packets to
>       be dropped before they reach their destination.

>   As an example, one possible approach to mitigate this threat is to
>   ignore very small hop limits.  The nodes could implement a
>   configurable minimum hop limit, and ignore attempts to set it below
>   said limit.

Signed-off-by: D.S. Ljungmark 
Acked-by: Hannes Frederic Sowa 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman