Refactor out allocation and initialization and make
the refcount code more readable.
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Similarly the code is already protected by rtnl lock.
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Similarly the code is already protected by rtnl lock.
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It's not used anywhere, so just remove these.
Signed-off-by: NDaniel Borkmann <dborkman@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Calling setsockopt with IPV6_JOIN_ANYCAST or IPV6_LEAVE_ANYCAST
triggers the assertion in addrconf_join_solict()/addrconf_leave_solict()

ipv6_sock_ac_join(), ipv6_sock_ac_drop(), ipv6_sock_ac_close() need to
take RTNL before calling ipv6_dev_ac_inc/dec. Same thing with
ipv6_sock_mc_join(), ipv6_sock_mc_drop(), ipv6_sock_mc_close() before
calling ipv6_dev_mc_inc/dec.

This patch moves ASSERT_RTNL() up a level in the call stack.
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NSabrina Dubroca <sd@queasysnail.net>
Reported-by: NTommi Rantala <tt.rantala@gmail.com>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds a new sysctl_mld_qrv knob to configure the mldv1/v2 query
robustness variable. It specifies how many retransmit of unsolicited mld
retransmit should happen. Admins might want to tune this on lossy links.

Also reset mld state on interface down/up, so we pick up new sysctl
settings during interface up event.

IPv6 certification requests this knob to be available.

I didn't make this knob netns specific, as it is mostly a setting in a
physical environment and should be per host.

Cc: Flavio Leitner <fbl@redhat.com>
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: NFlavio Leitner <fbl@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch makes no changes to the logic of the code but simply addresses
coding style issues as detected by checkpatch.

Both objdump and diff -w show no differences.

A number of items are addressed in this patch:
* Multiple spaces converted to tabs
* Spaces before tabs removed.
* Spaces in pointer typing cleansed (char *)foo etc.
* Remove space after sizeof
* Ensure spacing around comparators such as if statements.
Signed-off-by: NIan Morris <ipm@chirality.org.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Based on RFC3810 6.2, we also need to check the hop limit and router alert
option besides source address.
Signed-off-by: NHangbin Liu <liuhangbin@gmail.com>
Acked-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

After commit c15b1cca ("ipv6: move DAD and addrconf_verify
processing to workqueue") some counters are now updated in process context
and thus need to disable bh before doing so, otherwise deadlocks can
happen on 32-bit archs. Fabio Estevam noticed this while while mounting
a NFS volume on an ARM board.

As a compensation for missing this I looked after the other *_STATS_BH
and found three other calls which need updating:

1) icmp6_send: ip6_fragment -> icmpv6_send -> icmp6_send (error handling)
2) ip6_push_pending_frames: rawv6_sendmsg -> rawv6_push_pending_frames -> ...
   (only in case of icmp protocol with raw sockets in error handling)
3) ping6_v6_sendmsg (error handling)

Fixes: c15b1cca ("ipv6: move DAD and addrconf_verify processing to workqueue")
Reported-by: NFabio Estevam <festevam@gmail.com>
Tested-by: NFabio Estevam <fabio.estevam@freescale.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The RFC 3810 defines two type of messages for multicast
listeners. The "Current State Report" message, as the name
implies, refreshes the *current* state to the querier.
Since the querier sends Query messages periodically, there
is no need to retransmit the report.

On the other hand, any change should be reported immediately
using "State Change Report" messages. Since it's an event
triggered by a change and that it can be affected by packet
loss, the rfc states it should be retransmitted [RobVar] times
to make sure routers will receive timely.

Currently, we are sending "Current State Reports" after
DAD is completed.  Before that, we send messages using
unspecified address (::) which should be silently discarded
by routers.

This patch changes to send "State Change Report" messages
after DAD is completed fixing the behavior to be RFC compliant
and also to pass TAHI IPv6 testsuite.
Signed-off-by: NFlavio Leitner <fbl@redhat.com>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch removes the net_random and net_srandom macros and replaces
them with direct calls to the prandom ones. As new commits only seem to
use prandom_u32 there is no use to keep them around.
This change makes it easier to grep for users of prandom_u32.
Signed-off-by: NAruna-Hewapathirane <aruna.hewapathirane@gmail.com>
Suggested-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It is possible for the timer handlers to run after the call to
ipv6_mc_down so use in6_dev_put instead of __in6_dev_put in the
handler function in order to do proper cleanup when the refcnt
reaches 0. Otherwise, the refcnt can reach zero without the
inet6_dev being destroyed and we end up leaking a reference to
the net_device and see messages like the following,

unregister_netdevice: waiting for eth0 to become free. Usage count = 1

Tested on linux-3.4.43.
Signed-off-by: NSalam Noureddine <noureddine@aristanetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We already have mld_{gq,ifc,dad}_start_timer() functions, so introduce
mld_{gq,ifc,dad}_stop_timer() functions to reduce code size and make it
more readable.
Signed-off-by: NDaniel Borkmann <dborkman@redhat.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Make igmp6_event_query() a bit easier to read by refactoring code
parts into mld_process_v1() and mld_process_v2().
Signed-off-by: NDaniel Borkmann <dborkman@redhat.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Similarly as we do in MLDv2 queries, set a forged MLDv1 query with
0 ms mld_maxdelay to minimum timer shot time of 1 jiffies. This is
eventually done in igmp6_group_queried() anyway, so we can simplify
a check there.
Signed-off-by: NDaniel Borkmann <dborkman@redhat.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

RFC3810, 10. Security Considerations says under subsection 10.1.
Query Message:

  A forged Version 1 Query message will put MLDv2 listeners on that
  link in MLDv1 Host Compatibility Mode. This scenario can be avoided
  by providing MLDv2 hosts with a configuration option to ignore
  Version 1 messages completely.

Hence, implement a MLDv2-only mode that will ignore MLDv1 traffic:

  echo 2 > /proc/sys/net/ipv6/conf/ethX/force_mld_version  or
  echo 2 > /proc/sys/net/ipv6/conf/all/force_mld_version

Note that <all> device has a higher precedence as it was previously
also the case in the macro MLD_V1_SEEN() that would "short-circuit"
if condition on <all> case.
Signed-off-by: NDaniel Borkmann <dborkman@redhat.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Get rid of MLDV2_MRC and use our new macros for mantisse and
exponent to calculate Maximum Response Delay out of the Maximum
Response Code.
Signed-off-by: NDaniel Borkmann <dborkman@redhat.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Replace the macro with a function to make it more readable. GCC will
eventually decide whether to inline this or not (also, that's not
fast-path anyway).
Signed-off-by: NDaniel Borkmann <dborkman@redhat.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

i) RFC3810, 9.2. Query Interval [QI] says:

   The Query Interval variable denotes the interval between General
   Queries sent by the Querier. Default value: 125 seconds. [...]

ii) RFC3810, 9.3. Query Response Interval [QRI] says:

  The Maximum Response Delay used to calculate the Maximum Response
  Code inserted into the periodic General Queries. Default value:
  10000 (10 seconds) [...] The number of seconds represented by the
  [Query Response Interval] must be less than the [Query Interval].

iii) RFC3810, 9.12. Older Version Querier Present Timeout [OVQPT] says:

  The Older Version Querier Present Timeout is the time-out for
  transitioning a host back to MLDv2 Host Compatibility Mode. When an
  MLDv1 query is received, MLDv2 hosts set their Older Version Querier
  Present Timer to [Older Version Querier Present Timeout].

  This value MUST be ([Robustness Variable] times (the [Query Interval]
  in the last Query received)) plus ([Query Response Interval]).

Hence, on *default* the timeout results in:

  [RV] = 2, [QI] = 125sec, [QRI] = 10sec
  [OVQPT] = [RV] * [QI] + [QRI] = 260sec

Having that said, we currently calculate [OVQPT] (here given as 'switchback'
variable) as ...

  switchback = (idev->mc_qrv + 1) * max_delay

RFC3810, 9.12. says "the [Query Interval] in the last Query received". In
section "9.14. Configuring timers", it is said:

  This section is meant to provide advice to network administrators on
  how to tune these settings to their network. Ambitious router
  implementations might tune these settings dynamically based upon
  changing characteristics of the network. [...]

iv) RFC38010, 9.14.2. Query Interval:

  The overall level of periodic MLD traffic is inversely proportional
  to the Query Interval. A longer Query Interval results in a lower
  overall level of MLD traffic. The value of the Query Interval MUST
  be equal to or greater than the Maximum Response Delay used to
  calculate the Maximum Response Code inserted in General Query
  messages.

I assume that was why switchback is calculated as is (3 * max_delay), although
this setting seems to be meant for routers only to configure their [QI]
interval for non-default intervals. So usage here like this is clearly wrong.

Concluding, the current behaviour in IPv6's multicast code is not conform
to the RFC as switch back is calculated wrongly. That is, it has a too small
value, so MLDv2 hosts switch back again to MLDv2 way too early, i.e. ~30secs
instead of ~260secs on default.

Hence, introduce necessary helper functions and fix this up properly as it
should be.

Introduced in 06da92283 ("[IPV6]: Add MLDv2 support."). Credits to Hannes
Frederic Sowa who also had a hand in this as well. Also thanks to Hangbin Liu
who did initial testing.
Signed-off-by: NDaniel Borkmann <dborkman@redhat.com>
Cc: David Stevens <dlstevens@us.ibm.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Instead of hard-coding length values, use a define to make it clear
where those lengths come from.
Signed-off-by: NDaniel Borkmann <dborkman@redhat.com>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

For the functions mld_gq_start_timer(), mld_ifc_start_timer(),
and mld_dad_start_timer(), rather use unsigned long than int
as we operate only on unsigned values anyway. This seems more
appropriate as there is no good reason to do type conversions
to int, that could lead to future errors.
Signed-off-by: NDaniel Borkmann <dborkman@redhat.com>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use proper API functions to calculate jiffies from milliseconds and
not the crude method of dividing HZ by a value. This ensures more
accurate values even in the case of strange HZ values. While at it,
also simplify code in the mlh2 case by using max().
Signed-off-by: NDaniel Borkmann <dborkman@redhat.com>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit cab70040 ("net: igmp:
Reduce Unsolicited report interval to 1s when using IGMPv3") and
2690048c ("net: igmp: Allow user-space
configuration of igmp unsolicited report interval") by William Manley made
igmp unsolicited report intervals configurable per interface and corrected
the interval of unsolicited igmpv3 report messages resendings to 1s.

Same needs to be done for IPv6:

MLDv1 (RFC2710 7.10.): 10 seconds
MLDv2 (RFC3810 9.11.): 1 second

Both intervals are configurable via new procfs knobs
mldv1_unsolicited_report_interval and mldv2_unsolicited_report_interval.

(also added .force_mld_version to ipv6_devconf_dflt to bring structs in
line without semantic changes)

v2:
a) Joined documentation update for IPv4 and IPv6 MLD/IGMP
   unsolicited_report_interval procfs knobs.
b) incorporate stylistic feedback from William Manley

v3:
a) add new DEVCONF_* values to the end of the enum (thanks to David
   Miller)

Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: William Manley <william.manley@youview.com>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Cc: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

v2:
a) Also send ipv4 igmp messages with TC_PRIO_CONTROL

Cc: William Manley <william.manley@youview.com>
Cc: Lukas Tribus <luky-37@hotmail.com>
Acked-by: NBenjamin LaHaise <bcrl@kvack.org>
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

dingtianhong reported the following deadlock detected by lockdep:

 ======================================================
 [ INFO: possible circular locking dependency detected ]
 3.4.24.05-0.1-default #1 Not tainted
 -------------------------------------------------------
 ksoftirqd/0/3 is trying to acquire lock:
  (&ndev->lock){+.+...}, at: [<ffffffff8147f804>] ipv6_get_lladdr+0x74/0x120

 but task is already holding lock:
  (&mc->mca_lock){+.+...}, at: [<ffffffff8149d130>] mld_send_report+0x40/0x150

 which lock already depends on the new lock.

 the existing dependency chain (in reverse order) is:

 -> #1 (&mc->mca_lock){+.+...}:
        [<ffffffff810a8027>] validate_chain+0x637/0x730
        [<ffffffff810a8417>] __lock_acquire+0x2f7/0x500
        [<ffffffff810a8734>] lock_acquire+0x114/0x150
        [<ffffffff814f691a>] rt_spin_lock+0x4a/0x60
        [<ffffffff8149e4bb>] igmp6_group_added+0x3b/0x120
        [<ffffffff8149e5d8>] ipv6_mc_up+0x38/0x60
        [<ffffffff81480a4d>] ipv6_find_idev+0x3d/0x80
        [<ffffffff81483175>] addrconf_notify+0x3d5/0x4b0
        [<ffffffff814fae3f>] notifier_call_chain+0x3f/0x80
        [<ffffffff81073471>] raw_notifier_call_chain+0x11/0x20
        [<ffffffff813d8722>] call_netdevice_notifiers+0x32/0x60
        [<ffffffff813d92d4>] __dev_notify_flags+0x34/0x80
        [<ffffffff813d9360>] dev_change_flags+0x40/0x70
        [<ffffffff813ea627>] do_setlink+0x237/0x8a0
        [<ffffffff813ebb6c>] rtnl_newlink+0x3ec/0x600
        [<ffffffff813eb4d0>] rtnetlink_rcv_msg+0x160/0x310
        [<ffffffff814040b9>] netlink_rcv_skb+0x89/0xb0
        [<ffffffff813eb357>] rtnetlink_rcv+0x27/0x40
        [<ffffffff81403e20>] netlink_unicast+0x140/0x180
        [<ffffffff81404a9e>] netlink_sendmsg+0x33e/0x380
        [<ffffffff813c4252>] sock_sendmsg+0x112/0x130
        [<ffffffff813c537e>] __sys_sendmsg+0x44e/0x460
        [<ffffffff813c5544>] sys_sendmsg+0x44/0x70
        [<ffffffff814feab9>] system_call_fastpath+0x16/0x1b

 -> #0 (&ndev->lock){+.+...}:
        [<ffffffff810a798e>] check_prev_add+0x3de/0x440
        [<ffffffff810a8027>] validate_chain+0x637/0x730
        [<ffffffff810a8417>] __lock_acquire+0x2f7/0x500
        [<ffffffff810a8734>] lock_acquire+0x114/0x150
        [<ffffffff814f6c82>] rt_read_lock+0x42/0x60
        [<ffffffff8147f804>] ipv6_get_lladdr+0x74/0x120
        [<ffffffff8149b036>] mld_newpack+0xb6/0x160
        [<ffffffff8149b18b>] add_grhead+0xab/0xc0
        [<ffffffff8149d03b>] add_grec+0x3ab/0x460
        [<ffffffff8149d14a>] mld_send_report+0x5a/0x150
        [<ffffffff8149f99e>] igmp6_timer_handler+0x4e/0xb0
        [<ffffffff8105705a>] call_timer_fn+0xca/0x1d0
        [<ffffffff81057b9f>] run_timer_softirq+0x1df/0x2e0
        [<ffffffff8104e8c7>] handle_pending_softirqs+0xf7/0x1f0
        [<ffffffff8104ea3b>] __do_softirq_common+0x7b/0xf0
        [<ffffffff8104f07f>] __thread_do_softirq+0x1af/0x210
        [<ffffffff8104f1c1>] run_ksoftirqd+0xe1/0x1f0
        [<ffffffff8106c7de>] kthread+0xae/0xc0
        [<ffffffff814fff74>] kernel_thread_helper+0x4/0x10

actually we can just hold idev->lock before taking pmc->mca_lock,
and avoid taking idev->lock again when iterating idev->addr_list,
since the upper callers of mld_newpack() already take
read_lock_bh(&idev->lock).
Reported-by: Ndingtianhong <dingtianhong@huawei.com>
Cc: dingtianhong <dingtianhong@huawei.com>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Tested-by: NDing Tianhong <dingtianhong@huawei.com>
Tested-by: NChen Weilong <chenweilong@huawei.com>
Signed-off-by: NCong Wang <amwang@redhat.com>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

RFC3590/RFC3810 specifies we should resend MLD reports as soon as a
valid link-local address is available.

We now use the valid_ll_addr_cnt to check if it is necessary to resend
a new report.

Changes since Flavio Leitner's version:
a) adapt for valid_ll_addr_cnt
b) resend first reports directly in the path and just arm the timer for
   mc_qrv-1 resends.
Reported-by: NFlavio Leitner <fleitner@redhat.com>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: David Stevens <dlstevens@us.ibm.com>
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NFlavio Leitner <fbl@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This corrects an regression introduced by "net: Use 16bits for *_headers
fields of struct skbuff" when NET_SKBUFF_DATA_USES_OFFSET is not set. In
that case skb->tail will be a pointer whereas skb->transport_header
will be an offset from head. This is corrected by using wrappers that
ensure that comparisons and calculations are always made using pointers.
Signed-off-by: NSimon Horman <horms@verge.net.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

proc_net_remove is only used to remove proc entries
that under /proc/net,it's not a general function for
removing proc entries of netns. if we want to remove
some proc entries which under /proc/net/stat/, we still
need to call remove_proc_entry.

this patch use remove_proc_entry to replace proc_net_remove.
we can remove proc_net_remove after this patch.
Signed-off-by: NGao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Right now, some modules such as bonding use proc_create
to create proc entries under /proc/net/, and other modules
such as ipv4 use proc_net_fops_create.

It looks a little chaos.this patch changes all of
proc_net_fops_create to proc_create. we can remove
proc_net_fops_create after this patch.
Signed-off-by: NGao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

RFC4291 (IPv6 addressing architecture) says that interface-Local scope
spans only a single interface on a node.  We should not join L2 device
multicast list for addresses in interface-local (or smaller) scope.
Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

With the loop, don't check 'rv' twice in a row. Without the loop, 'rv'
doesn't even need to be checked.

Make the comment more grammar-friendly.
Signed-off-by: NJean Sacren <sakiwit@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

- move ip6_nd_hdr() to its users' source files.
  In net/ipv6/mcast.c, it will be called ip6_mc_hdr().
- make return type to void since this function never fails.
Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Because of rt->n removal, we do not need neigh argument any more.
Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Move generalized version of ipv6_is_mld() to header,
and use it from ip6_mc_input().
Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

ipv6_sock_mc_close() is called for ipv6 sockets at close time, and most
of them don't use multicast.

Add a test to avoid contention on a shared spinlock.

Same heuristic applies for ipv6_sock_ac_close(), to avoid contention
on a shared rwlock.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As suggested by Eric, we could introduce a helper function
for ipv6 too, to avoid checking if rt is NULL before
dst_release().

Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: NCong Wang <amwang@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We need to check the passed in multicast address and return
appropriate errno(EINVAL) if it is not valid. And it's no need
to walk through the ipv6_mc_list in this situation.
Signed-off-by: NLi Wei <lw@cn.fujitsu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Mostly bool conversions, some inline removals and const additions.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>