Make all seq_operations structs const, to help mitigate against
revectoring user-triggerable function pointers.

This is derived from the grsecurity patch, although generated from scratch
because it's simpler than extracting the changes from there.
Signed-off-by: NJames Morris <jmorris@namei.org>
Acked-by: NSerge Hallyn <serue@us.ibm.com>
Acked-by: NCasey Schaufler <casey@schaufler-ca.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If an interface has multiple addresses, the current message for DAD
failure isn't really helpful, so this patch adds the address itself to
the printk.
Signed-off-by: NJens Rosenboom <me@jayr.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

RFC4191 says that "If the Reserved (10) value is received, the Route
Information Option MUST be ignored.", so this patch makes us conform
to the RFC. This is different to the usage of the Default Router
Preference, where an invalid value must indeed be treated as
PREF_MEDIUM.
Signed-off-by: NJens Rosenboom <me@jayr.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch fixes commit e36b9d16. The approach
there is to call dev_close()/dev_open() whenever the device type is changed in
order to remap the device IP multicast addresses to HW multicast addresses.
This approach suffers from 2 drawbacks:

*. It assumes tha the device is UP when calling dev_close(), or otherwise
   dev_close() has no affect. It is worth to mention that initscripts (Redhat)
   and sysconfig (Suse) doesn't act the same in this matter. 
*. dev_close() has other side affects, like deleting entries from the routing
   table, which might be unnecessary.

The fix here is to directly remap the IP multicast addresses to HW multicast
addresses for a bonding device that changes its type, and nothing else.
Reported-by: NJason Gunthorpe <jgunthorpe@obsidianresearch.com>
Signed-off-by: NMoni Shoua <monis@voltaire.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It was once upon time so that snd_sthresh was a 16-bit quantity.
...That has not been true for long period of time. I run across
some ancient compares which still seem to trust such legacy.
Put all that magic into a single place, I hopefully found all
of them.

Compile tested, though linking of allyesconfig is ridiculous
nowadays it seems.
Signed-off-by: NIlpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add IFA_F_DADFAILED flag to denote an IPv6 address that has
failed Duplicate Address Detection, that way tools like
/sbin/ip can be more informative.

3: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qlen 1000
    inet6 2001:db8::1/64 scope global tentative dadfailed
       valid_lft forever preferred_lft forever
Signed-off-by: NBrian Haley <brian.haley@hp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Here is a patch which fixes an issue observed when using TCP over IPv6
and AH from IPsec.

When a connection gets closed the 4-way method and the last ACK from
the server gets dropped, the subsequent FINs from the client do not
get ACKed because tcp_v6_send_response does not set the transport
header pointer. This causes ah6_output to try to allocate a lot of
memory, which typically fails, so the ACKs never make it out of the
stack.

I have reproduced the problem on kernel 2.6.7, but after looking at
the latest kernel it seems the problem is still there.
Signed-off-by: NCosmin Ratiu <cratiu@ixiacom.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This fixed a lockdep warning which appeared when doing stress
memory tests over NFS:

	inconsistent {RECLAIM_FS-ON-W} -> {IN-RECLAIM_FS-W} usage.

	page reclaim => nfs_writepage => tcp_sendmsg => lock sk_lock

	mount_root => nfs_root_data => tcp_close => lock sk_lock =>
			tcp_send_fin => alloc_skb_fclone => page reclaim

David raised a concern that if the allocation fails in tcp_send_fin(), and it's
GFP_ATOMIC, we are going to yield() (which sleeps) and loop endlessly waiting
for the allocation to succeed.

But fact is, the original GFP_KERNEL also sleeps. GFP_ATOMIC+yield() looks
weird, but it is no worse the implicit sleep inside GFP_KERNEL. Both could
loop endlessly under memory pressure.

CC: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
CC: David S. Miller <davem@davemloft.net>
CC: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NWu Fengguang <fengguang.wu@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Christoph Lameter pointed out that packet drops at qdisc level where not
accounted in SNMP counters. Only if application sets IP_RECVERR, drops
are reported to user (-ENOBUFS errors) and SNMP counters updated.

IP_RECVERR is used to enable extended reliable error message passing,
but these are not needed to update system wide SNMP stats.

This patch changes things a bit to allow SNMP counters to be updated,
regardless of IP_RECVERR being set or not on the socket.

Example after an UDP tx flood
# netstat -s 
...
IP:
    1487048 outgoing packets dropped
...
Udp:
...
    SndbufErrors: 1487048


send() syscalls, do however still return an OK status, to not
break applications.

Note : send() manual page explicitly says for -ENOBUFS error :

 "The output queue for a network interface was full.
  This generally indicates that the interface has stopped sending,
  but may be caused by transient congestion.
  (Normally, this does not occur in Linux. Packets are just silently
  dropped when a device queue overflows.) "

This is not true for IP_RECVERR enabled sockets : a send() syscall
that hit a qdisc drop returns an ENOBUFS error.

Many thanks to Christoph, David, and last but not least, Alexey !
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

All instances of file_operations should be const.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The function block inet_connect_sock_af_ops contains no data
make it constant.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

qdisc drops should be notified to IP_RECVERR enabled sockets, as done in IPV4.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

These tables are never modified at runtime. Move to read-only
section.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

struct net::ipv6.ip6_dst_ops is separatedly dynamically allocated,
but there is no fundamental reason for it. Embed it directly into
struct netns_ipv6.

For that:
* move struct dst_ops into separate header to fix circular dependencies
	I honestly tried not to, it's pretty impossible to do other way
* drop dynamical allocation, allocate together with netns

For a change, remove struct dst_ops::dst_net, it's deducible
by using container_of() given dst_ops pointer.
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use memcmp() instead of open coded comparison that reads one byte past
the intended end.

Based on patch from Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: NPatrick McHardy <kaber@trash.net>

When processing a received IPv6 Router Advertisement, the kernel
creates or updates an IPv6 Neighbor Cache entry for the sender --
but presently this does not occur if IPv6 forwarding is enabled
(net.ipv6.conf.*.forwarding = 1), or if IPv6 Router Advertisements
are not accepted (net.ipv6.conf.*.accept_ra = 0), because in these
cases processing of the Router Advertisement has already halted.

This patch allows the Neighbor Cache to be updated in these cases,
while still avoiding any modification to routes or link parameters.

This continues to satisfy RFC 4861, since any entry created in the
Neighbor Cache as the result of a received Router Advertisement is
still placed in the STALE state.
Signed-off-by: NDavid Ward <david.ward@ll.mit.edu>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

if tunnel parameters have frag_off set to IP_DF, pmtudisc on the ipv4 link
will be performed by deriving the mtu from the ipv4 link and setting the
DF-Flag of the encapsulating IPv4 Header. If fragmentation is needed on the
way, the IPv4 pmtu gets adjusted, the ipv6 package will be resent eventually,
using the new and lower mtu and everyone is happy.

If the frag_off parameter is unset, the mtu for the tunnel will be derived
from the tunnel device or the ipv6 pmtu, which might be higher than the ipv4
pmtu. In that case we must allow the fragmentation of the IPv4 packet because
the IPv6 mtu wouldn't 'learn' from the adjusted IPv4 pmtu, resulting in
frequent icmp_frag_needed and package loss on the IPv6 layer.

This patch allows fragmentation when tunnel was created with parameter
nopmtudisc, like in ipip/gre tunnels.
Signed-off-by: NSascha Hlusiak <contact@saschahlusiak.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Log packets dropped by helpers using the netfilter logging API. This
is useful in combination with nfnetlink_log to analyze those packets
in userspace for debugging.
Signed-off-by: NPatrick McHardy <kaber@trash.net>

The inputted table is never modified, so should be considered const.
Signed-off-by: NJan Engelhardt <jengelh@medozas.de>
Signed-off-by: NPatrick McHardy <kaber@trash.net>

ipv6: Fix commit 63d9950b (ipv6: Make v4-mapped bindings consistent with IPv4)

Commit 63d9950b
  (ipv6: Make v4-mapped bindings consistent with IPv4)
changes behavior of inet6_bind() for v4-mapped addresses so it should
behave the same way as inet_bind().

During this change setting of err to -EADDRNOTAVAIL got lost:

af_inet.c:469 inet_bind()
	err = -EADDRNOTAVAIL;
	if (!sysctl_ip_nonlocal_bind &&
	    !(inet->freebind || inet->transparent) &&
	    addr->sin_addr.s_addr != htonl(INADDR_ANY) &&
	    chk_addr_ret != RTN_LOCAL &&
	    chk_addr_ret != RTN_MULTICAST &&
	    chk_addr_ret != RTN_BROADCAST)
		goto out;


af_inet6.c:463 inet6_bind()
	if (addr_type == IPV6_ADDR_MAPPED) {
		int chk_addr_ret;

		/* Binding to v4-mapped address on a v6-only socket                         
		 * makes no sense                                                           
		 */
		if (np->ipv6only) {
			err = -EINVAL;
			goto out; 
		}

		/* Reproduce AF_INET checks to make the bindings consitant */               
		v4addr = addr->sin6_addr.s6_addr32[3];                                      
		chk_addr_ret = inet_addr_type(net, v4addr);                                 
		if (!sysctl_ip_nonlocal_bind &&                                             
		    !(inet->freebind || inet->transparent) &&                               
		    v4addr != htonl(INADDR_ANY) &&
		    chk_addr_ret != RTN_LOCAL &&                                            
		    chk_addr_ret != RTN_MULTICAST &&                                        
		    chk_addr_ret != RTN_BROADCAST)
			goto out;
	} else {


Signed-off-by Bruno Prémont <bonbons@linux-vserver.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch addresses:
 * assigning -1 to np->tclass as it is currently done is not very meaningful,
   since it turns into 0xff;
 * RFC 3542, 6.5 allows -1 for clearing the sticky IPV6_TCLASS option
   and specifies -1 to mean "use kernel default":
   - RFC 2460, 7. requires that the default traffic class must be zero for
     all 8 bits,
   - this is consistent with RFC 2474, 4.1 which recommends a default PHB of 0,
     in combination with a value of the ECN field of "non-ECT" (RFC 3168, 5.).

This patch changes the meaning of -1 from assigning 255 to mean the RFC 2460
default, which at the same time allows to satisfy clearing the sticky TCLASS
option as per RFC 3542, 6.5.

(When passing -1 as ancillary data, the fallback remains np->tclass, which
 has either been set via socket options, or contains the default value.)
Signed-off-by: NGerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This replaces assignments of the type "int on LHS" = "u8 on RHS" with
simpler code. The LHS can express all of the unsigned right hand side
values, hence the assigned value can not be negative.
Signed-off-by: NGerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If an interface has multiple addresses, the current message for DAD
failure isn't really helpful, so this patch adds the address itself to
the printk.
Signed-off-by: NJens Rosenboom <jens@mcbone.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This adds the second check that Rusty wanted to have a long time ago. :-)

Base chain policies must have absolute verdicts that cease processing
in the table, otherwise rule execution may continue in an unexpected
spurious fashion (e.g. next chain that follows in memory).
Signed-off-by: NJan Engelhardt <jengelh@medozas.de>

This adds a check that iptables's original author Rusty set forth in
a FIXME comment.

Underflows in iptables are better known as chain policies, and are
required to be unconditional or there would be a stochastical chance
for the policy rule to be skipped if it does not match. If that were
to happen, rule execution would continue in an unexpected spurious
fashion.
Signed-off-by: NJan Engelhardt <jengelh@medozas.de>

The "hook_entry" and "underflow" array contains values even for hooks
not provided, such as PREROUTING in conjunction with the "filter"
table. Usually, the values point to whatever the next rule is. For
the upcoming unconditionality and underflow checking patches however,
we must not inspect that arbitrary rule.

Skipping unassigned hooks seems like a good idea, also because
newinfo->hook_entry and newinfo->underflow will then continue to have
the poison value for detecting abnormalities.
Signed-off-by: NJan Engelhardt <jengelh@medozas.de>

Instead of inspecting each u32/char open-coded, clean up and make use
of memcmp. On some arches, memcmp is implemented as assembly or GCC's
__builtin_memcmp which can possibly take advantages of known
alignment.
Signed-off-by: NJan Engelhardt <jengelh@medozas.de>

Signed-off-by: NJan Engelhardt <jengelh@medozas.de>

Signed-off-by: NJan Engelhardt <jengelh@medozas.de>

Simple substitution to indicate that the fields indeed use the
NFPROTO_ space.
Signed-off-by: NJan Engelhardt <jengelh@medozas.de>

String literals are constant, and usually, we can also tag the array
of pointers const too, moving it to the .rodata section.
Signed-off-by: NJan Engelhardt <jengelh@medozas.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Same as how Randy Dunlap fixed the ipv4 side of things.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This renames away a variable clash:
 * ipv6_table[] is declared as a static global table;
 * ipv6_sysctl_net_init() uses ipv6_table to refer/destroy dynamic memory;
 * ipv6_sysctl_net_exit() also uses ipv6_table for the same purpose;
 * both the two last functions call kfree() on ipv6_table.
Signed-off-by: NGerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Choose saner defaults for xfrm[4|6] gc_thresh values on init

Currently, the xfrm[4|6] code has hard-coded initial gc_thresh values
(set to 1024).  Given that the ipv4 and ipv6 routing caches are sized
dynamically at boot time, the static selections can be non-sensical.
This patch dynamically selects an appropriate gc threshold based on
the corresponding main routing table size, using the assumption that
we should in the worst case be able to handle as many connections as
the routing table can.

For ipv4, the maximum route cache size is 16 * the number of hash
buckets in the route cache.  Given that xfrm4 starts garbage
collection at the gc_thresh and prevents new allocations at 2 *
gc_thresh, we set gc_thresh to half the maximum route cache size.

For ipv6, its a bit trickier.  there is no maximum route cache size,
but the ipv6 dst_ops gc_thresh is statically set to 1024.  It seems
sane to select a simmilar gc_thresh for the xfrm6 code that is half
the number of hash buckets in the v6 route cache times 16 (like the v4
code does).
Signed-off-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Export garbage collector thresholds for xfrm[4|6]_dst_ops

Had a problem reported to me recently in which a high volume of ipsec
connections on a system began reporting ENOBUFS for new connections
eventually.

It seemed that after about 2000 connections we started being unable to
create more.  A quick look revealed that the xfrm code used a dst_ops
structure that limited the gc_thresh value to 1024, and always
dropped route cache entries after 2x the gc_thresh.

It seems the most direct solution is to export the gc_thresh values in
the xfrm[4|6] dst_ops as sysctls, like the main routing table does, so
that higher volumes of connections can be supported.  This patch has
been tested and allows the reporter to increase their ipsec connection
volume successfully.
Reported-by: NJoe Nall <joe@nall.com>
Signed-off-by: NNeil Horman <nhorman@tuxdriver.com>

ipv4/xfrm4_policy.c |   18 ++++++++++++++++++
ipv6/xfrm6_policy.c |   18 ++++++++++++++++++
2 files changed, 36 insertions(+)
Signed-off-by: NDavid S. Miller <davem@davemloft.net>