linux-stable.git/net/ipv4/igmp.c, branch linux-3.13.y

ipv4 igmp: use in_dev_put in timer handlers instead of __in_dev_put

2013-10-01T05:28:56+00:00

It is possible for the timer handlers to run after the call to
ip_mc_down so use in_dev_put instead of __in_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 in_device 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: Salam Noureddine 
Signed-off-by: David S. Miller

ip: generate unique IP identificator if local fragmentation is allowed

2013-09-19T18:11:15+00:00

If local fragmentation is allowed, then ip_select_ident() and
ip_select_ident_more() need to generate unique IDs to ensure
correct defragmentation on the peer.

For example, if IPsec (tunnel mode) has to encrypt large skbs
that have local_df bit set, then all IP fragments that belonged
to different ESP datagrams would have used the same identificator.
If one of these IP fragments would get lost or reordered, then
peer could possibly stitch together wrong IP fragments that did
not belong to the same datagram. This would lead to a packet loss
or data corruption.

Signed-off-by: Ansis Atteka 
Signed-off-by: David S. Miller

net: igmp: Allow user-space configuration of igmp unsolicited report interval

2013-08-09T18:27:46+00:00

Adds the new procfs knobs:

    /proc/sys/net/ipv4/conf/*/igmpv2_unsolicited_report_interval
    /proc/sys/net/ipv4/conf/*/igmpv3_unsolicited_report_interval

Which will allow userspace configuration of the IGMP unsolicited report
interval (see below) in milliseconds.  The defaults are 10000ms for IGMPv2
and 1000ms for IGMPv3 in accordance with RFC2236 and RFC3376.

Background:

If an IGMP join packet is lost you will not receive data sent to the
multicast group so if no data arrives from that multicast group in a
period of time after the IGMP join a second IGMP join will be sent.  The
delay between joins is the "IGMP Unsolicited Report Interval".

Prior to this patch this value was hard coded in the kernel to 10s for
IGMPv2 and 1s for IGMPv3.  10s is unsuitable for some use-cases, such as
IPTV as it can cause channel change to be slow in the presence of packet
loss.

This patch allows the value to be overridden from userspace for both
IGMPv2 and IGMPv3 such that it can be tuned accoding to the network.

Tested with Wireshark and a simple program to join a (non-existent)
multicast group.  The distribution of timings for the second join differ
based upon setting the procfs knobs.

igmpvX_unsolicited_report_interval is intended to follow the pattern
established by force_igmp_version, and while a procfs entry has been added
a corresponding sysctl knob has not as it is my understanding that sysctl
is deprecated[1].

[1]: http://lwn.net/Articles/247243/

Signed-off-by: William Manley 
Acked-by: Hannes Frederic Sowa 
Acked-by: Benjamin LaHaise 
Signed-off-by: David S. Miller

net: igmp: Reduce Unsolicited report interval to 1s when using IGMPv3

2013-08-09T18:27:46+00:00

If an IGMP join packet is lost you will not receive data sent to the
multicast group so if no data arrives from that multicast group in a
period of time after the IGMP join a second IGMP join will be sent.  The
delay between joins is the "IGMP Unsolicited Report Interval".

Previously this value was hard coded to be chosen randomly between 0-10s.
This can be too long for some use-cases, such as IPTV as it can cause
channel change to be slow in the presence of packet loss.

The value 10s has come from IGMPv2 RFC2236, which was reduced to 1s in
IGMPv3 RFC3376.  This patch makes the kernel use the 1s value from the
later RFC if we are operating in IGMPv3 mode.  IGMPv2 behaviour is
unaffected.

Tested with Wireshark and a simple program to join a (non-existent)
multicast group.  The distribution of timings for the second join differ
based upon setting /proc/sys/net/ipv4/conf/eth0/force_igmp_version.

Signed-off-by: William Manley 
Acked-by: Hannes Frederic Sowa 
Acked-by: Benjamin LaHaise 
Signed-off-by: David S. Miller

ipv4, ipv6: send igmpv3/mld packets with TC_PRIO_CONTROL

2013-07-28T18:13:55+00:00

v2:
a) Also send ipv4 igmp messages with TC_PRIO_CONTROL

Cc: William Manley 
Cc: Lukas Tribus 
Acked-by: Benjamin LaHaise 
Signed-off-by: Hannes Frederic Sowa 
Signed-off-by: David S. Miller

net: convert resend IGMP to notifier event

2013-07-23T23:52:47+00:00

Until now, bond_resend_igmp_join_requests() looks for vlans attached to
bonding device, bridge where bonding act as port manually. It does not
care of other scenarios, like stacked bonds or team device above. Make
this more generic and use netdev notifier to propagate the event to
upper devices and to actually call ip_mc_rejoin_groups().

Signed-off-by: Jiri Pirko 
Acked-by: Veaceslav Falico 
Signed-off-by: David S. Miller

igmp: fix new sparse errors

2013-06-12T21:14:55+00:00

Fix following sparse errors :

net/ipv4/igmp.c:1222:25: warning: cast from restricted __be32
net/ipv4/igmp.c:1234:31: warning: incorrect type in assignment (different address spaces)
net/ipv4/igmp.c:1234:31:    expected struct ip_mc_list [noderef] *next_hash
net/ipv4/igmp.c:1234:31:    got struct ip_mc_list *
net/ipv4/igmp.c:1250:31: warning: incorrect type in assignment (different address spaces)
net/ipv4/igmp.c:1250:31:    expected struct ip_mc_list [noderef] *next_hash
net/ipv4/igmp.c:1250:31:    got struct ip_mc_list *
net/ipv4/igmp.c:2380:37: warning: cast from restricted __be32

These were added by commit e9897071350bd9
("igmp: hash a hash table to speedup ip_check_mc_rcu()")

Reported-by: kbuild test robot 
Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller

igmp: remove unnecessary in_device member zeroing

2013-06-12T07:41:15+00:00

ip_mc_init_dev() is passed a freshly kzalloc'd in_device so it is
unnecessary to explicitly zero out the members.

Signed-off-by: Shawn Bohrer 
Signed-off-by: David S. Miller

igmp: hash a hash table to speedup ip_check_mc_rcu()

2013-06-12T07:25:23+00:00

After IP route cache removal, multicast applications using
a lot of multicast addresses hit a O(N) behavior in ip_check_mc_rcu()

Add a per in_device hash table to get faster lookup.

This hash table is created only if the number of items in mc_list is
above 4.

Reported-by: Shawn Bohrer 
Signed-off-by: Eric Dumazet 
Tested-by: Shawn Bohrer 
Reviewed-by: Cong Wang 
Signed-off-by: David S. Miller

ipv4: Correct comparisons and calculations using skb->tail and skb-transport_header

2013-05-29T06:49:07+00:00

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: Simon Horman 
Signed-off-by: David S. Miller