linux-toradex.git/include/net/dst.h, branch v3.2.2

net: introduce DST_NOPEER dst flag

2011-12-23T03:34:56+00:00

Chris Boot reported crashes occurring in ipv6_select_ident().

[  461.457562] RIP: 0010:[]  []
ipv6_select_ident+0x31/0xa7

[  461.578229] Call Trace:
[  461.580742] 
[  461.582870]  [] ? udp6_ufo_fragment+0x124/0x1a2
[  461.589054]  [] ? ipv6_gso_segment+0xc0/0x155
[  461.595140]  [] ? skb_gso_segment+0x208/0x28b
[  461.601198]  [] ? ipv6_confirm+0x146/0x15e
[nf_conntrack_ipv6]
[  461.608786]  [] ? nf_iterate+0x41/0x77
[  461.614227]  [] ? dev_hard_start_xmit+0x357/0x543
[  461.620659]  [] ? nf_hook_slow+0x73/0x111
[  461.626440]  [] ? br_parse_ip_options+0x19a/0x19a
[bridge]
[  461.633581]  [] ? dev_queue_xmit+0x3af/0x459
[  461.639577]  [] ? br_dev_queue_push_xmit+0x72/0x76
[bridge]
[  461.646887]  [] ? br_nf_post_routing+0x17d/0x18f
[bridge]
[  461.653997]  [] ? nf_iterate+0x41/0x77
[  461.659473]  [] ? br_flood+0xfa/0xfa [bridge]
[  461.665485]  [] ? nf_hook_slow+0x73/0x111
[  461.671234]  [] ? br_flood+0xfa/0xfa [bridge]
[  461.677299]  [] ?
nf_bridge_update_protocol+0x20/0x20 [bridge]
[  461.684891]  [] ? nf_ct_zone+0xa/0x17 [nf_conntrack]
[  461.691520]  [] ? br_flood+0xfa/0xfa [bridge]
[  461.697572]  [] ? NF_HOOK.constprop.8+0x3c/0x56
[bridge]
[  461.704616]  [] ?
nf_bridge_push_encap_header+0x1c/0x26 [bridge]
[  461.712329]  [] ? br_nf_forward_finish+0x8a/0x95
[bridge]
[  461.719490]  [] ?
nf_bridge_pull_encap_header+0x1c/0x27 [bridge]
[  461.727223]  [] ? br_nf_forward_ip+0x1c0/0x1d4 [bridge]
[  461.734292]  [] ? nf_iterate+0x41/0x77
[  461.739758]  [] ? __br_deliver+0xa0/0xa0 [bridge]
[  461.746203]  [] ? nf_hook_slow+0x73/0x111
[  461.751950]  [] ? __br_deliver+0xa0/0xa0 [bridge]
[  461.758378]  [] ? NF_HOOK.constprop.4+0x56/0x56
[bridge]

This is caused by bridge netfilter special dst_entry (fake_rtable), a
special shared entry, where attaching an inetpeer makes no sense.

Problem is present since commit 87c48fa3b46 (ipv6: make fragment
identifications less predictable)

Introduce DST_NOPEER dst flag and make sure ipv6_select_ident() and
__ip_select_ident() fallback to the 'no peer attached' handling.

Reported-by: Chris Boot 
Tested-by: Chris Boot 
Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller

net: Move mtu handling down to the protocol depended handlers

2011-11-26T19:29:51+00:00

We move all mtu handling from dst_mtu() down to the protocol
layer. So each protocol can implement the mtu handling in
a different manner.

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

net: Rename the dst_opt default_mtu method to mtu

2011-11-26T19:29:50+00:00

We plan to invoke the dst_opt->default_mtu() method unconditioally
from dst_mtu(). So rename the method to dst_opt->mtu() to match
the name with the new meaning.

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

rps: Add flag to skb to indicate rxhash is based on L4 tuple

2011-08-18T03:06:03+00:00

The l4_rxhash flag was added to the skb structure to indicate
that the rxhash value was computed over the 4 tuple for the
packet which includes the port information in the encapsulated
transport packet.  This is used by the stack to preserve the
rxhash value in __skb_rx_tunnel.

Signed-off-by: Tom Herbert 
Signed-off-by: David S. Miller

net: fix NULL dereferences in check_peer_redir()

2011-08-03T10:34:12+00:00

Gergely Kalman reported crashes in check_peer_redir().

It appears commit f39925dbde778 (ipv4: Cache learned redirect
information in inetpeer.) added a race, leading to possible NULL ptr
dereference.

Since we can now change dst neighbour, we should make sure a reader can
safely use a neighbour.

Add RCU protection to dst neighbour, and make sure check_peer_redir()
can be called safely by different cpus in parallel.

As neighbours are already freed after one RCU grace period, this patch
should not add typical RCU penalty (cache cold effects)

Many thanks to Gergely for providing a pretty report pointing to the
bug.

Reported-by: Gergely Kalman 
Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller

net: Add ->neigh_lookup() operation to dst_ops

2011-07-18T07:40:17+00:00

In the future dst entries will be neigh-less.  In that environment we
need to have an easy transition point for current users of
dst->neighbour outside of the packet output fast path.

Signed-off-by: David S. Miller

net: Abstract dst->neighbour accesses behind helpers.

2011-07-18T06:11:35+00:00

dst_{get,set}_neighbour()

Signed-off-by: David S. Miller

net: Embed hh_cache inside of struct neighbour.

2011-07-14T14:53:20+00:00

Now that there is a one-to-one correspondance between neighbour
and hh_cache entries, we no longer need:

1) dynamic allocation
2) attachment to dst->hh
3) refcounting

Initialization of the hh_cache entry is indicated by hh_len
being non-zero, and such initialization is always done with
the neighbour's lock held as a writer.

Signed-off-by: David S. Miller

ipv6: Don't put artificial limit on routing table size.

2011-07-02T00:30:43+00:00

IPV6, unlike IPV4, doesn't have a routing cache.

Routing table entries, as well as clones made in response
to route lookup requests, all live in the same table.  And
all of these things are together collected in the destination
cache table for ipv6.

This means that routing table entries count against the garbage
collection limits, even though such entries cannot ever be reclaimed
and are added explicitly by the administrator (rather than being
created in response to lookups).

Therefore it makes no sense to count ipv6 routing table entries
against the GC limits.

Add a DST_NOCOUNT destination cache entry flag, and skip the counting
if it is set.  Use this flag bit in ipv6 when adding routing table
entries.

Signed-off-by: David S. Miller

dst: catch uninitialized metrics

2011-05-24T17:50:52+00:00

Catch cases where dst_metric_set() and other functions are called
but _metrics is NULL.

Signed-off-by: Stephen Hemminger 
Signed-off-by: David S. Miller