There is no obvious reason to add a default multicast route for loopback
devices, otherwise there would be a route entry whose dst.error set to
-ENETUNREACH that would blocking all multicast packets.

====================

[ more detailed explanation ]

The problem is that the resulting routing table depends on the sequence
of interface's initialization and in some situation, that would block all
muticast packets. Suppose there are two interfaces on my computer
(lo and eth0), if we initailize 'lo' before 'eth0', the resuting routing
table(for multicast) would be

# ip -6 route show | grep ff00::
unreachable ff00::/8 dev lo metric 256 error -101
ff00::/8 dev eth0 metric 256

When sending multicasting packets, routing subsystem will return the first
route entry which with a error set to -101(ENETUNREACH).

I know the kernel will set the default ipv6 address for 'lo' when it is up
and won't set the default multicast route for it, but there is no reason to
stop 'init' program from setting address for 'lo', and that is exactly what
systemd did.

I am sure there is something wrong with kernel or systemd, currently I preferred
kernel caused this problem.

====================
Signed-off-by: NLi Wei <lw@cn.fujitsu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This reverts commit 81d54ec8.

If we take the "try_again" goto, due to a checksum error,
the 'len' has already been truncated.  So we won't compute
the same values as the original code did.
Reported-by: Npaul bilke <fsmail@conspiracy.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We need to set np->mcast_hops to it's default value at this moment
otherwise when we use it and found it's value is -1, the logic to
get default hop limit doesn't take multicast into account and will
return wrong hop limit(IPV6_DEFAULT_HOPLIMIT) which is for unicast.
Signed-off-by: NLi Wei <lw@cn.fujitsu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: NSteffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: NSteffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As it is, we return null as the default mtu of blackhole routes.
This may lead to a propagation of a bogus pmtu if the default_mtu
method of a blackhole route is invoked. So return dst->dev->mtu
as the default mtu instead.
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since linux 2.6.26 (commit c6aefafb : Add IPv6 support to TCP SYN
cookies), we can drop a SYN packet reusing a TIME_WAIT socket.

(As a matter of fact we fail to send the SYNACK answer)

As the client resends its SYN packet after a one second timeout, we
accept it, because first packet removed the TIME_WAIT socket before
being dropped.

This probably explains why nobody ever noticed or complained.
Reported-by: NJesse Young <jlyo@jlyo.org>
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Distributions are using this in their default scripts, so don't hide
them behind the advanced setting.
Reported-by: NLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

commit 72a3effa ([NET]: Size listen hash tables using backlog
hint) added a bug allowing inet6_synq_hash() to return an out of bound
array index, because of u16 overflow.

Bug can happen if system admins set net.core.somaxconn &
net.ipv4.tcp_max_syn_backlog sysctls to values greater than 65536
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Release skb when transmit rate limit _not_ allow
Signed-off-by: NLi Wei <lw@cn.fujitsu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit 1c5cae81 removed an explicit call to dev_alloc_name in ip6_tnl_create
because register_netdevice will now create a valid name.  This works for the
net_device itself.

However the tunnel keeps a copy of the name in the parms structure for the
ip6_tnl associated with the tunnel.  parms.name is set by copying the net_device
name in ip6_tnl_dev_init_gen.  That function is called from ip6_tnl_dev_init in
ip6_tnl_create, but it is done before register_netdevice is called so the name
is set to a bogus value in the parms.name structure.

This shows up if you do a simple tunnel add, followed by a tunnel show:

[root@localhost ~]# ip -6 tunnel add remote fec0::100 local fec0::200
[root@localhost ~]# ip -6 tunnel show
ip6tnl0: ipv6/ipv6 remote :: local :: encaplimit 0 hoplimit 0 tclass 0x00 flowlabel 0x00000 (flowinfo 0x00000000)
ip6tnl%d: ipv6/ipv6 remote fec0::100 local fec0::200 encaplimit 4 hoplimit 64 tclass 0x00 flowlabel 0x00000 (flowinfo 0x00000000)
[root@localhost ~]#

Fix this by moving the strcpy out of ip6_tnl_dev_init_gen, and calling it after
register_netdevice has successfully returned.

Cc: stable@vger.kernel.org
Signed-off-by: NJosh Boyer <jwboyer@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When the ahash driver returns -EBUSY, AH4/6 input functions return
NET_XMIT_DROP, presumably copied from the output code path.  But
returning transmit codes on input doesn't make a lot of sense.
Since NET_XMIT_DROP is a positive int, this gets interpreted as
the next header type (i.e., success).  As that can only end badly,
remove the check.
Signed-off-by: NNick Bowler <nbowler@elliptictech.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The AH4/6 ahash input callbacks read out the nexthdr field from the AH
header *after* they overwrite that header.  This is obviously not going
to end well.  Fix it up.
Signed-off-by: NNick Bowler <nbowler@elliptictech.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The AH4/6 ahash output callbacks pass nexthdr to xfrm_output_resume
instead of the error code.  This appears to be a copy+paste error from
the input case, where nexthdr is expected.  This causes the driver to
continuously add AH headers to the datagram until either an allocation
fails and the packet is dropped or the ahash driver hits a synchronous
fallback and the resulting monstrosity is transmitted.

Correct this issue by simply passing the error code unadulterated.
Signed-off-by: NNick Bowler <nbowler@elliptictech.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

RFC 4291 Section 2.7 says Multicast addresses must not be used as source
addresses in IPv6 packets - drop them on input so we don't process the
packet further.
Signed-off-by: NBrian Haley <brian.haley@hp.com>
Reported-and-Tested-by: NKumar Sanghvi <divinekumar@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

the tcp and udp code creates a set of struct file_operations at runtime
while it can also be done at compile time, with the added benefit of then
having these file operations be const.

the trickiest part was to get the "THIS_MODULE" reference right; the naive
method of declaring a struct in the place of registration would not work
for this reason.
Signed-off-by: NArjan van de Ven <arjan@linux.intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Several callers (h323 conntrack, xt_addrtype) assume that the
returned **dst only needs to be released if the function returns 0.

This is true for the ipv4 implementation, but not for the ipv6 one.

Instead of changing the users, change the ipv6 implementation
to behave like the ipv4 version by only providing the dst_entry result
in the success case.
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

Site specific OOM messages are duplications of a generic MM
out of memory message and aren't really useful, so just
delete them.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

These files are non modular, but need to export symbols using
the macros now living in export.h -- call out the include so
that things won't break when we remove the implicit presence
of module.h from everywhere.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>

The route lookup to find a previously auto-configured route for a prefixes used
to use rt6_lookup(), with the prefix from the RA used as an address. However,
that kind of lookup ignores routing tables, the prefix length and route flags,
so when there were other matching routes, even in different tables and/or with
a different prefix length, the wrong route would be manipulated.

Now, a new function "addrconf_get_prefix_route()" is used for the route lookup,
which searches in RT6_TABLE_PREFIX and takes the prefix-length and route flags
into account.
Signed-off-by: NAndreas Hofmeister <andi@collax.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

in func icmp6_dst_alloc,dst_metric_set call ipv6_cow_metrics to set metric.
ipv6_cow_metrics may will call rt6_bind_peer to set rt6_info->rt6i_peer.
So,we should move ipv6_addr_copy before dst_metric_set to make sure rt6_bind_peer success.
Signed-off-by: NGao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We should return errcode from sock_alloc_send_skb()
Signed-off-by: NZheng Yan <zheng.z.yan@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

commit 66b13d99 (ipv4: tcp: fix TOS value in ACK messages sent from
TIME_WAIT) fixed IPv4 only.

This part is for the IPv6 side, adding a tclass param to ip6_xmit()

We alias tw_tclass and tw_tos, if socket family is INET6.

[ if sockets is ipv4-mapped, only IP_TOS socket option is used to fill
TOS field, TCLASS is not taken into account ]
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When hybrid mode is enabled (accept_ra == 2), the kernel also sees RAs
generated locally. This is useful since it allows the kernel to auto-configure
its own interface addresses.

However, if 'accept_ra_defrtr' and/or 'accept_ra_rtr_pref' are set and the
locally generated RAs announce the default route and/or other route information,
the kernel happily inserts bogus routes with its own address as gateway.

With this patch, adding routes from an RA will be skiped when the RAs source
address matches any local address, just as if 'accept_ra_defrtr' and
'accept_ra_rtr_pref' were set to 0.
Signed-off-by: NAndreas Hofmeister <andi@collax.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now tcp_md5_hash_header() has a const tcphdr argument, we can add more
const attributes to callers.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Adding const qualifiers to pointers can ease code review, and spot some
bugs. It might allow compiler to optimize code further.

For example, is it legal to temporary write a null cksum into tcphdr
in tcp_md5_hash_header() ? I am afraid a sniffer could catch the
temporary null value...
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Up till now the IP{,V6}_TRANSPARENT socket options (which actually set
the same bit in the socket struct) have required CAP_NET_ADMIN
privileges to set or clear the option.

- we make clearing the bit not require any privileges.
- we allow CAP_NET_ADMIN to set the bit (as before this change)
- we allow CAP_NET_RAW to set this bit, because raw
  sockets already pretty much effectively allow you
  to emulate socket transparency.
Signed-off-by: NMaciej Żenczykowski <maze@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This cleanup patch removes unnecessary include from net/ipv6/ip6_fib.c.
Signed-off-by: NKevin Wilson <wkevils@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

To ease skb->truesize sanitization, its better to be able to localize
all references to skb frags size.

Define accessors : skb_frag_size() to fetch frag size, and
skb_frag_size_{set|add|sub}() to manipulate it.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Calling icmpv6_send() on a local message size error leads to
an incorrect update of the path mtu. So use xfrm6_local_rxpmtu()
to notify about the pmtu if the IPV6_DONTFRAG socket option is
set on an udp or raw socket, according RFC 3542 and use
ipv6_local_error() otherwise.
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

ip6_append_data() builds packets based on the mtu from dst_mtu(rt->dst.path).
On IPsec the effective mtu is lower because we need to add the protocol
headers and trailers later when we do the IPsec transformations. So after
the IPsec transformations the packet might be too big, which leads to a
slowpath fragmentation then. This patch fixes this by building the packets
based on the lower IPsec mtu from dst_mtu(&rt->dst) and adapts the exthdr
handling to this.
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The pointer to mtu_info is taken from the common buffer
of the skb, thus it can't be a NULL pointer. This patch
removes this check on mtu_info.
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

in6_dev_get(dev) takes a reference on struct inet6_dev, we dont need
rcu locking in ndisc_constructor()
Signed-off-by: NRoy.Li <rongqing.li@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

skb truesize currently accounts for sk_buff struct and part of skb head.
kmalloc() roundings are also ignored.

Considering that skb_shared_info is larger than sk_buff, its time to
take it into account for better memory accounting.

This patch introduces SKB_TRUESIZE(X) macro to centralize various
assumptions into a single place.

At skb alloc phase, we put skb_shared_info struct at the exact end of
skb head, to allow a better use of memory (lowering number of
reallocations), since kmalloc() gives us power-of-two memory blocks.

Unless SLUB/SLUB debug is active, both skb->head and skb_shared_info are
aligned to cache lines, as before.

Note: This patch might trigger performance regressions because of
misconfigured protocol stacks, hitting per socket or global memory
limits that were previously not reached. But its a necessary step for a
more accurate memory accounting.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
CC: Andi Kleen <ak@linux.intel.com>
CC: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

ipv6_gro_receive() doesn't update the protocol ops after pulling
the ext headers. It looks like a typo.
Signed-off-by: NZheng Yan <zheng.z.yan@intel.com>
Acked-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

tcp_v4_clear_md5_list() assumes that multiple tcp md5sig peers
only hold one reference to md5sig_pool. but tcp_v4_md5_do_add()
increases use count of md5sig_pool for each peer. This patch
makes tcp_v4_md5_do_add() only increases use count for the first
tcp md5sig peer.
Signed-off-by: NZheng Yan <zheng.z.yan@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

ipv6_ac_list and ipv6_fl_list from listening socket are inadvertently
shared with new socket created for connection.
Signed-off-by: NZheng Yan <zheng.z.yan@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If reg_vif_xmit cannot find a routing entry, be sure to
free the skb before returning the error.
Signed-off-by: NBen Greear <greearb@candelatech.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

return value of dst_alloc must be checked before use
Signed-off-by: NMadalin Bucur <madalin.bucur@freescale.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Have to free the skb before returning if we fail
the fib lookup.
Signed-off-by: NBen Greear <greearb@candelatech.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>