misc: uidstat: avoid create_stat() race and blockage.

* create_stat() race would lead to:
  [   58.132324] proc_dir_entry 'uid_stat/10061' already registered

* blocking kmalloc reported by sbranden
 tcp_read_sock()
  uid_stat_tcp_rcv()
    create_stat()
      kmalloc(GFP_KERNEL)

Signed-off-by: JP Abgrall <jpa@google.com>
Backport ipv6 addrconf.c and dependencies from 3.0.101
Fixes kernel nonstop spamming on ipv6 networks, preventing the device from entering in standby and generating ipv6 traffic affecting phone performance

The dmesg was like this:

<7>[11432.377075,1] p2p0: GOT RA with prefix : rlft 0, vlft 921600,plft 230400, period 0
<7>[11432.377288,1] p2p0: GOT RA with prefix : rlft 0, vlft 921600,plft 230400, period 0
<7>[11432.377441,1] wlan0: GOT RA with prefix : rlft 0, vlft 921600,plft 230400, period 0
<7>[11432.377624,1] wlan0: GOT RA with prefix : rlft 0, vlft 921600,plft 230400, period 0
<7>[11432.379455,1] p2p0: GOT RA with prefix : rlft 0, vlft 921600,plft 230400, period 0
<7>[11432.379577,1] p2p0: GOT RA with prefix : rlft 0, vlft 921600,plft 230400, period 0
<7>[11432.379821,1] wlan0: GOT RA with prefix : rlft 0, vlft 921600,plft 230400, period 0
<7>[11432.380004,1] wlan0: GOT RA with prefix : rlft 0, vlft 921600,plft 230400, period 0
<7>[11432.381622,1] p2p0: RS timer expired.
<7>[11432.381927,1] p2p0: RS timer expired.
<7>[11432.382080,1] wlan0: RS timer expired.
<7>[11432.382202,1] wlan0: RS timer expired.

Change-Id: I03f76a03528e7b12da742c57fa18d0d49f8b08ee
ipv6: fix bad free of addrconf_init_net

[ Upstream commit a79ca223e029aa4f09abb337accf1812c900a800 ]

Signed-off-by: Hong Zhiguo <honkiko@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
inet: limit length of fragment queue hash table bucket lists

[ Upstream commit 5a3da1fe9561828d0ca7eca664b16ec2b9bf0055 ]

This patch introduces a constant limit of the fragment queue hash
table bucket list lengths. Currently the limit 128 is choosen somewhat
arbitrary and just ensures that we can fill up the fragment cache with
empty packets up to the default ip_frag_high_thresh limits. It should
just protect from list iteration eating considerable amounts of cpu.

If we reach the maximum length in one hash bucket a warning is printed.
This is implemented on the caller side of inet_frag_find to distinguish
between the different users of inet_fragment.c.

I dropped the out of memory warning in the ipv4 fragment lookup path,
because we already get a warning by the slab allocator.

Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Jesper Dangaard Brouer <jbrouer@redhat.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ipv6: stop multicast forwarding to process interface scoped addresses

[ Upstream commit ddf64354af4a702ee0b85d0a285ba74c7278a460 ]

v2:
a) used struct ipv6_addr_props

v3:
a) reverted changes for ipv6_addr_props

v4:
a) do not use __ipv6_addr_needs_scope_id

Cc: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ipv6: introdcue __ipv6_addr_needs_scope_id and ipv6_iface_scope_id helper functions

[net-next commit b7ef213ef65256168df83ddfbb8131ed9adc10f9]

__ipv6_addr_needs_scope_id checks if an ipv6 address needs to supply
a 'sin6_scope_id != 0'. 'sin6_scope_id != 0' was enforced in case
of link-local addresses. To support interface-local multicast these
checks had to be enhanced and are now consolidated into these new helper
functions.

v2:
a) migrated to struct ipv6_addr_props

v3:
a) reverted changes for ipv6_addr_props
b) test for address type instead of comparing scope

v4:
a) unchanged

Change-Id: Id6fc54cec61f967928e08a9eba4f857157d973a3
Suggested-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Cc: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Acked-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
ipv4: fix a bug in ping_err().

[ Upstream commit b531ed61a2a2a77eeb2f7c88b49aa5ec7d9880d8 ]

We should get 'type' and 'code' from the outer ICMP header.

Signed-off-by: Li Wei <lw@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>