Commit Graph

204 Commits

Author SHA1 Message Date
Bob Gilligan 53385d2d1d neigh: Netlink notification for administrative NUD state change
The neighbour code sends up an RTM_NEWNEIGH netlink notification if
the NUD state of a neighbour cache entry is changed by a timer (e.g.
from REACHABLE to STALE), even if the lladdr of the entry has not
changed.

But an administrative change to the the NUD state of a neighbour cache
entry that does not change the lladdr (e.g. via "ip -4 neigh change
...  nud ...") does not trigger a netlink notification.  This means
that netlink listeners will not hear about administrative NUD state
changes such as from a resolved state to PERMANENT.

This patch changes the neighbor code to generate an RTM_NEWNEIGH
message when the NUD state of an entry is changed administratively.

Signed-off-by: Bob Gilligan <gilligan@aristanetworks.com>
Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-17 16:14:35 -05:00
Hannes Frederic Sowa 4ed377e36e net: neighbour: use source address of last enqueued packet for solicitation
Currently we always use the first member of the arp_queue to determine
the sender ip address of the arp packet (or in case of IPv6 - source
address of the ndisc packet). This skb is fixed as long as the queue is
not drained by a complete purge because of a timeout or by a successful
response.

If the first packet enqueued on the arp_queue is from a local application
with a manually set source address and the to be discovered system
does some kind of uRPF checks on the source address in the arp packet
the resolving process hangs until a timeout and restarts. This hurts
communication with the participating network node.

This could be mitigated a bit if we use the latest enqueued skb's
source address for the resolving process, which is not as static as
the arp_queue's head. This change of the source address could result in
better recovery of a failed solicitation.

Cc: "David S. Miller" <davem@davemloft.net>
Cc: Julian Anastasov <ja@ssi.bg>
Reviewed-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-26 13:46:10 -04:00
Tim Gardner 3e25c65ed0 net: neighbour: Remove CONFIG_ARPD
This config option is superfluous in that it only guards a call
to neigh_app_ns(). Enabling CONFIG_ARPD by default has no
change in behavior. There will now be call to __neigh_notify()
for each ARP resolution, which has no impact unless there is a
user space daemon waiting to receive the notification, i.e.,
the case for which CONFIG_ARPD was designed anyways.

Suggested-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: James Morris <jmorris@namei.org>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: Patrick McHardy <kaber@trash.net>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Gao feng <gaofeng@cn.fujitsu.com>
Cc: Joe Perches <joe@perches.com>
Cc: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Reviewed-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-03 21:41:43 -04:00
David S. Miller 0e76a3a587 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Merge net into net-next to setup some infrastructure Eric
Dumazet needs for usbnet changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-03 21:36:46 -07:00
Veaceslav Falico 63134803a6 neighbour: populate neigh_parms on alloc before calling ndo_neigh_setup
dev->ndo_neigh_setup() might need some of the values of neigh_parms, so
populate them before calling it.

Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-02 15:44:23 -07:00
Francesco Fusco 555445cd11 neigh: prevent overflowing params in /proc/sys/net/ipv4/neigh/
Without this patch, the fields app_solicit, gc_thresh1, gc_thresh2,
gc_thresh3, proxy_qlen, ucast_solicit, mcast_solicit could have
assumed negative values when setting large numbers.

Signed-off-by: Francesco Fusco <ffusco@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-26 14:22:10 -07:00
Eric Dumazet c9ab4d85de neighbour: fix a race in neigh_destroy()
There is a race in neighbour code, because neigh_destroy() uses
skb_queue_purge(&neigh->arp_queue) without holding neighbour lock,
while other parts of the code assume neighbour rwlock is what
protects arp_queue

Convert all skb_queue_purge() calls to the __skb_queue_purge() variant

Use __skb_queue_head_init() instead of skb_queue_head_init()
to make clear we do not use arp_queue.lock

And hold neigh->lock in neigh_destroy() to close the race.

Reported-by: Joe Jin <joe.jin@oracle.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-01 13:35:32 -07:00
Gao feng dc25c676f5 neigh: disallow un-init_net to change thresh of neigh
thresh and interval are global resources,
only init net can change them.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-19 21:13:24 -07:00
Gao feng 170d6f9954 neigh: only allow init_net to change the default neigh_parms
Though we don't export the /proc/sys/net/ipv[4,6]/neigh/default/
directory to the un-init_net, but we can still use cmd such as
"ip ntable change name arp_cache locktime 129" to change the locktime
of default neigh_parms.

This patch disallows the un-init_net to find out the neigh_table.parms.
So the un-init_net will failed to influence the init_net.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-19 21:13:24 -07:00
Gao feng cf89d6b280 neigh: no need to call lookup_neigh_parms in neigh_parms_alloc
neigh_table.parms always exist and is initialized,kmemdup
can use it to create new neigh_parms, actually lookup_neigh_parms
here will return neigh_table.parms too.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-19 21:13:24 -07:00
Joe Perches fe2c6338fd net: Convert uses of typedef ctl_table to struct ctl_table
Reduce the uses of this unnecessary typedef.

Done via perl script:

$ git grep --name-only -w ctl_table net | \
  xargs perl -p -i -e '\
	sub trim { my ($local) = @_; $local =~ s/(^\s+|\s+$)//g; return $local; } \
        s/\b(?<!struct\s)ctl_table\b(\s*\*\s*|\s+\w+)/"struct ctl_table " . trim($1)/ge'

Reflow the modified lines that now exceed 80 columns.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-13 02:36:09 -07:00
Linus Torvalds 20b4fb4852 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull VFS updates from Al Viro,

Misc cleanups all over the place, mainly wrt /proc interfaces (switch
create_proc_entry to proc_create(), get rid of the deprecated
create_proc_read_entry() in favor of using proc_create_data() and
seq_file etc).

7kloc removed.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (204 commits)
  don't bother with deferred freeing of fdtables
  proc: Move non-public stuff from linux/proc_fs.h to fs/proc/internal.h
  proc: Make the PROC_I() and PDE() macros internal to procfs
  proc: Supply a function to remove a proc entry by PDE
  take cgroup_open() and cpuset_open() to fs/proc/base.c
  ppc: Clean up scanlog
  ppc: Clean up rtas_flash driver somewhat
  hostap: proc: Use remove_proc_subtree()
  drm: proc: Use remove_proc_subtree()
  drm: proc: Use minor->index to label things, not PDE->name
  drm: Constify drm_proc_list[]
  zoran: Don't print proc_dir_entry data in debug
  reiserfs: Don't access the proc_dir_entry in r_open(), r_start() r_show()
  proc: Supply an accessor for getting the data from a PDE's parent
  airo: Use remove_proc_subtree()
  rtl8192u: Don't need to save device proc dir PDE
  rtl8187se: Use a dir under /proc/net/r8180/
  proc: Add proc_mkdir_data()
  proc: Move some bits from linux/proc_fs.h to linux/{of.h,signal.h,tty.h}
  proc: Move PDE_NET() to fs/proc/proc_net.c
  ...
2013-05-01 17:51:54 -07:00
Joe Perches d5d427cdae neighbour: Convert NEIGH_PRINTK to neigh_dbg
Update debugging messages to a more current style.

Emit these debugging messages at KERN_DEBUG instead
of KERN_DEFAULT.

Add and use neigh_dbg(level, fmt, ...) macro
Add dynamic_debug capability via pr_debug
Convert embedded function names to "%s: ", __func__

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-16 16:34:08 -04:00
Al Viro d9dda78bad procfs: new helper - PDE_DATA(inode)
The only part of proc_dir_entry the code outside of fs/proc
really cares about is PDE(inode)->data.  Provide a helper
for that; static inline for now, eventually will be moved
to fs/proc, along with the knowledge of struct proc_dir_entry
layout.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-04-09 14:13:32 -04:00
Thomas Graf 661d2967b3 rtnetlink: Remove passing of attributes into rtnl_doit functions
With decnet converted, we can finally get rid of rta_buf and its
computations around it. It also gets rid of the minimal header
length verification since all message handlers do that explicitly
anyway.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-22 10:31:16 -04:00
YOSHIFUJI Hideaki / 吉藤英明 08433eff2d net neigh: Optimize neighbor entry size calculation.
When allocating memory for neighbour cache entry, if
tbl->entry_size is not set, we always calculate
sizeof(struct neighbour) + tbl->key_len, which is common
in the same table.

With this change, set tbl->entry_size during the table
initialization phase, if it was not set, and use it in
neigh_alloc() and neighbour_priv().

This change also allow us to have both of protocol private
data and device priate data at tha same time.

Note that the only user of prototcol private is DECnet
and the only user of device private is ATM CLIP.
Since those are exclusive, we have not been facing issues
here.

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-01-28 23:17:51 -05:00
YOSHIFUJI Hideaki / 吉藤英明 2724680bce neigh: Keep neighbour cache entries if number of them is small enough.
Since we have removed NCE (Neighbour Cache Entry) reference from
routing entries, the only refcnt holders of an NCE are its timer
(if running) and its owner table, in usual cases.  As a result,
neigh_periodic_work() purges NCEs over and over again even for
gateways.

It does not make sense to purge entries, if number of them is
very small, so keep them.  The minimum number of entries to keep
is specified by gc_thresh1.

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-01-22 14:25:28 -05:00
Cong Wang b93196dc5a net: fix some compiler warning in net/core/neighbour.c
net/core/neighbour.c:65:12: warning: 'zero' defined but not used [-Wunused-variable]
net/core/neighbour.c:66:12: warning: 'unres_qlen_max' defined but not used [-Wunused-variable]

These variables are only used when CONFIG_SYSCTL is defined,
so move them under #ifdef CONFIG_SYSCTL.

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Cong Wang <amwang@redhat.com>
Acked-by: Shan Wei <davidshan@tencent.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-12-05 21:50:37 -05:00
Shan Wei ce46cc64d4 net: neighbour: prohibit negative value for unres_qlen_bytes parameter
unres_qlen_bytes and unres_qlen are int type.
But multiple relation(unres_qlen_bytes = unres_qlen * SKB_TRUESIZE(ETH_FRAME_LEN))
will cause type overflow when seting unres_qlen. e.g.

$ echo 1027506 > /proc/sys/net/ipv4/neigh/eth1/unres_qlen
$ cat /proc/sys/net/ipv4/neigh/eth1/unres_qlen
1182657265
$ cat /proc/sys/net/ipv4/neigh/eth1/unres_qlen_bytes
-2147479756

The gutted value is not that we setting。
But user/administrator don't know this is caused by int type overflow.

what's more, it is meaningless and even dangerous that unres_qlen_bytes is set
with negative number. Because, for unresolved neighbour address, kernel will cache packets
without limit in __neigh_event_send()(e.g. (u32)-1 = 2GB).

Signed-off-by: Shan Wei <davidshan@tencent.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-12-05 16:01:28 -05:00
Eric W. Biederman b51642f6d7 net: Enable a userns root rtnl calls that are safe for unprivilged users
- Only allow moving network devices to network namespaces you have
  CAP_NET_ADMIN privileges over.

- Enable creating/deleting/modifying interfaces
- Enable adding/deleting addresses
- Enable adding/setting/deleting neighbour entries
- Enable adding/removing routes
- Enable adding/removing fib rules
- Enable setting the forwarding state
- Enable adding/removing ipv6 address labels
- Enable setting bridge parameter

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-18 20:33:36 -05:00
Eric W. Biederman dfc47ef863 net: Push capable(CAP_NET_ADMIN) into the rtnl methods
- In rtnetlink_rcv_msg convert the capable(CAP_NET_ADMIN) check
  to ns_capable(net->user-ns, CAP_NET_ADMIN).  Allowing unprivileged
  users to make netlink calls to modify their local network
  namespace.

- In the rtnetlink doit methods add capable(CAP_NET_ADMIN) so
  that calls that are not safe for unprivileged users are still
  protected.

Later patches will remove the extra capable calls from methods
that are safe for unprivilged users.

Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-18 20:32:44 -05:00
Eric W. Biederman 464dc801c7 net: Don't export sysctls to unprivileged users
In preparation for supporting the creation of network namespaces
by unprivileged users, modify all of the per net sysctl exports
and refuse to allow them to unprivileged users.

This makes it safe for unprivileged users in general to access
per net sysctls, and allows sysctls to be exported to unprivileged
users on an individual basis as they are deemed safe.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-18 20:30:55 -05:00
ramesh.nagappa@gmail.com e1f165032c net: Fix skb_under_panic oops in neigh_resolve_output
The retry loop in neigh_resolve_output() and neigh_connected_output()
call dev_hard_header() with out reseting the skb to network_header.
This causes the retry to fail with skb_under_panic. The fix is to
reset the network_header within the retry loop.

Signed-off-by: Ramesh Nagappa <ramesh.nagappa@ericsson.com>
Reviewed-by: Shawn Lu <shawn.lu@ericsson.com>
Reviewed-by: Robert Coulson <robert.coulson@ericsson.com>
Reviewed-by: Billie Alsup <billie.alsup@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-10-07 14:42:39 -04:00
Linus Torvalds aecdc33e11 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking changes from David Miller:

 1) GRE now works over ipv6, from Dmitry Kozlov.

 2) Make SCTP more network namespace aware, from Eric Biederman.

 3) TEAM driver now works with non-ethernet devices, from Jiri Pirko.

 4) Make openvswitch network namespace aware, from Pravin B Shelar.

 5) IPV6 NAT implementation, from Patrick McHardy.

 6) Server side support for TCP Fast Open, from Jerry Chu and others.

 7) Packet BPF filter supports MOD and XOR, from Eric Dumazet and Daniel
    Borkmann.

 8) Increate the loopback default MTU to 64K, from Eric Dumazet.

 9) Use a per-task rather than per-socket page fragment allocator for
    outgoing networking traffic.  This benefits processes that have very
    many mostly idle sockets, which is quite common.

    From Eric Dumazet.

10) Use up to 32K for page fragment allocations, with fallbacks to
    smaller sizes when higher order page allocations fail.  Benefits are
    a) less segments for driver to process b) less calls to page
    allocator c) less waste of space.

    From Eric Dumazet.

11) Allow GRO to be used on GRE tunnels, from Eric Dumazet.

12) VXLAN device driver, one way to handle VLAN issues such as the
    limitation of 4096 VLAN IDs yet still have some level of isolation.
    From Stephen Hemminger.

13) As usual there is a large boatload of driver changes, with the scale
    perhaps tilted towards the wireless side this time around.

Fix up various fairly trivial conflicts, mostly caused by the user
namespace changes.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1012 commits)
  hyperv: Add buffer for extended info after the RNDIS response message.
  hyperv: Report actual status in receive completion packet
  hyperv: Remove extra allocated space for recv_pkt_list elements
  hyperv: Fix page buffer handling in rndis_filter_send_request()
  hyperv: Fix the missing return value in rndis_filter_set_packet_filter()
  hyperv: Fix the max_xfer_size in RNDIS initialization
  vxlan: put UDP socket in correct namespace
  vxlan: Depend on CONFIG_INET
  sfc: Fix the reported priorities of different filter types
  sfc: Remove EFX_FILTER_FLAG_RX_OVERRIDE_IP
  sfc: Fix loopback self-test with separate_tx_channels=1
  sfc: Fix MCDI structure field lookup
  sfc: Add parentheses around use of bitfield macro arguments
  sfc: Fix null function pointer in efx_sriov_channel_type
  vxlan: virtual extensible lan
  igmp: export symbol ip_mc_leave_group
  netlink: add attributes to fdb interface
  tg3: unconditionally select HWMON support when tg3 is enabled.
  Revert "net: ti cpsw ethernet: allow reading phy interface mode from DT"
  gre: fix sparse warning
  ...
2012-10-02 13:38:27 -07:00
Eric W. Biederman 15e473046c netlink: Rename pid to portid to avoid confusion
It is a frequent mistake to confuse the netlink port identifier with a
process identifier.  Try to reduce this confusion by renaming fields
that hold port identifiers portid instead of pid.

I have carefully avoided changing the structures exported to
userspace to avoid changing the userspace API.

I have successfully built an allyesconfig kernel with this change.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-09-10 15:30:41 -04:00
Tejun Heo 203b42f731 workqueue: make deferrable delayed_work initializer names consistent
Initalizers for deferrable delayed_work are confused.

* __DEFERRED_WORK_INITIALIZER()
* DECLARE_DEFERRED_WORK()
* INIT_DELAYED_WORK_DEFERRABLE()

Rename them to

* __DEFERRABLE_WORK_INITIALIZER()
* DECLARE_DEFERRABLE_WORK()
* INIT_DEFERRABLE_WORK()

This patch doesn't cause any functional changes.

Signed-off-by: Tejun Heo <tj@kernel.org>
2012-08-21 13:18:23 -07:00
David S. Miller 13a43d94ab neigh: Convert over to dst_neigh_lookup_skb().
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-05 01:12:00 -07:00
David S. Miller a263b30936 ipv4: Make neigh lookups directly in output packet path.
Do not use the dst cached neigh, we'll be getting rid of that.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-05 01:02:12 -07:00
Eric Dumazet 4bd6683bd4 net: neighbour: fix neigh_dump_info()
Denys found out "ip neigh" output was truncated to
about 54 neighbours.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Denys Fedoryshchenko <denys@visp.net.lb>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-06-07 13:02:21 -07:00
Joe Perches e005d193d5 net: core: Use pr_<level>
Use the current logging style.

This enables use of dynamic debugging as well.

Convert printk(KERN_<LEVEL> to pr_<level>.
Add pr_fmt. Remove embedded prefixes, use
%s, __func__ instead.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-05-17 05:00:04 -04:00
Eric W. Biederman 8f40a1f982 net neighbour: Convert to use register_net_sysctl
Using an ascii path to register_net_sysctl as opposed to the slightly
awkward ctl_path allows for much simpler code.

We no longer need to malloc dev_name to keep it alive the length of our
sysctl register instead we can use a small temporary buffer on the
stack.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-20 21:22:29 -04:00
Eric W. Biederman 5dd3df105b net: Move all of the network sysctls without a namespace into init_net.
This makes it clearer which sysctls are relative to your current network
namespace.

This makes it a little less error prone by not exposing sysctls for the
initial network namespace in other namespaces.

This is the same way we handle all of our other network interfaces to
userspace and I can't honestly remember why we didn't do this for
sysctls right from the start.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-20 21:21:17 -04:00
Eric Dumazet 95c9617472 net: cleanup unsigned to unsigned int
Use of "unsigned int" is preferred to bare "unsigned" in net tree.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-15 12:44:40 -04:00
Hiroaki SHIMODA dcd2ba92e8 neighbour: Make neigh_table_init_no_netlink() static.
neigh_table_init_no_netlink() is only used in net/core/neighbour.c file.

Signed-off-by: Hiroaki SHIMODA <shimoda.hiroaki@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-13 14:00:44 -04:00
David S. Miller 9a6308d74e neighbour: Stop using NLA_PUT*().
These macros contain a hidden goto, and are thus extremely error
prone and make code hard to audit.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-02 04:33:42 -04:00
David S. Miller ff4783ce78 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/sfc/rx.c

Overlapping changes in drivers/net/ethernet/sfc/rx.c, one to change
the rx_buf->is_page boolean into a set of u16 flags, and another to
adjust how ->ip_summed is initialized.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-02-26 21:55:51 -05:00
Michel Machado 84338a6c9d neighbour: Fixed race condition at tbl->nht
When the fixed race condition happens:

1. While function neigh_periodic_work scans the neighbor hash table
pointed by field tbl->nht, it unlocks and locks tbl->lock between
buckets in order to call cond_resched.

2. Assume that function neigh_periodic_work calls cond_resched, that is,
the lock tbl->lock is available, and function neigh_hash_grow runs.

3. Once function neigh_hash_grow finishes, and RCU calls
neigh_hash_free_rcu, the original struct neigh_hash_table that function
neigh_periodic_work was using doesn't exist anymore.

4. Once back at neigh_periodic_work, whenever the old struct
neigh_hash_table is accessed, things can go badly.

Signed-off-by: Michel Machado <michel@digirati.com.br>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-02-21 16:28:10 -05:00
Tony Zelenoff 84920c1420 net: Allow ipv6 proxies and arp proxies be shown with iproute2
Add ability to return neighbour proxies list to caller if
it sent full ndmsg structure and has NTF_PROXY flag set.

Before this patch (and before iproute2 patches):
$ ip neigh add proxy 2001::1 dev eth0
$ ip -6 neigh show
$

After it and with applied iproute2 patches:
$ ip neigh add proxy 2001::1 dev eth0
$ ip -6 neigh show
2001::1 dev eth0  proxy
$

Compatibility with old versions of iproute2 is not broken,
kernel checks for incoming structure size and properly
works if old structure is came.

[v2]
* changed comments style.
* removed useless line with continue and curly bracket.
* changed incoming message size check from equal to more or
  equal.

CC: davem@davemloft.net
CC: kuznet@ms2.inr.ac.ru
CC: netdev@vger.kernel.org
CC: xemul@parallels.com
Signed-off-by: Tony Zelenoff <antonz@parallels.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-30 12:57:34 -05:00
David S. Miller 2c2aba6c56 ipv6: Use universal hash for NDISC.
In order to perform a proper universal hash on a vector of integers,
we have to use different universal hashes on each vector element.

Which means we need 4 different hash randoms for ipv6.

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-28 15:06:58 -05:00
David S. Miller 447f219190 Revert "net: Remove unused neighbour layer ops."
This reverts commit 5c3ddec73d.

S390 qeth driver actually still uses the setup ops.

Reported-by: Frank Blaschka <blaschka@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-19 15:04:41 -05:00
David S. Miller 5c3ddec73d net: Remove unused neighbour layer ops.
It's simpler to just keep these things out until there is a real user
of them, so we can see what the needs actually are, rather than keep
these things around as useless overhead.

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-13 16:44:22 -05:00
David Miller 2721745501 net: Rename dst_get_neighbour{, _raw} to dst_get_neighbour_noref{, _raw}.
To reflect the fact that a refrence is not obtained to the
resulting neighbour entry.

Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Roland Dreier <roland@purestorage.com>
2011-12-05 15:20:19 -05:00
David Miller da6a8fa027 neigh: Add device constructor/destructor capability.
If the neigh entry has device private state, it will need
constructor/destructor ops.

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-30 18:48:03 -05:00
David Miller 596b9b68ef neigh: Add infrastructure for allocating device neigh privates.
netdev->neigh_priv_len records the private area length.

This will trigger for neigh_table objects which set tbl->entry_size
to zero, and the first instances of this will be forthcoming.

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-30 18:46:43 -05:00
David Miller 5b8b0060cb neigh: Get rid of neigh_table->kmem_cachep
We are going to alloc for device specific private areas for
neighbour entries, and in order to do that we have to move
away from the fixed allocation size enforced by using
neigh_table->kmem_cachep

As a nice side effect we can now use kfree_rcu().

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-30 18:46:43 -05:00
David S. Miller 6dec4ac4ee Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	net/ipv4/inet_diag.c
2011-11-26 14:47:03 -05:00
Jorge Boncompte [DTI2] df07a94cf5 netns: fix proxy ARP entries listing on a netns
Skip entries from foreign network namespaces.

Signed-off-by: Jorge Boncompte [DTI2] <jorge@dti2.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-25 13:24:49 -05:00
Eric Dumazet 8b5c171bb3 neigh: new unresolved queue limits
Le mercredi 09 novembre 2011 à 16:21 -0500, David Miller a écrit :
> From: David Miller <davem@davemloft.net>
> Date: Wed, 09 Nov 2011 16:16:44 -0500 (EST)
>
> > From: Eric Dumazet <eric.dumazet@gmail.com>
> > Date: Wed, 09 Nov 2011 12:14:09 +0100
> >
> >> unres_qlen is the number of frames we are able to queue per unresolved
> >> neighbour. Its default value (3) was never changed and is responsible
> >> for strange drops, especially if IP fragments are used, or multiple
> >> sessions start in parallel. Even a single tcp flow can hit this limit.
> >  ...
> >
> > Ok, I've applied this, let's see what happens :-)
>
> Early answer, build fails.
>
> Please test build this patch with DECNET enabled and resubmit.  The
> decnet neigh layer still refers to the removed ->queue_len member.
>
> Thanks.

Ouch, this was fixed on one machine yesterday, but not the other one I
used this morning, sorry.

[PATCH V5 net-next] neigh: new unresolved queue limits

unres_qlen is the number of frames we are able to queue per unresolved
neighbour. Its default value (3) was never changed and is responsible
for strange drops, especially if IP fragments are used, or multiple
sessions start in parallel. Even a single tcp flow can hit this limit.

$ arp -d 192.168.20.108 ; ping -c 2 -s 8000 192.168.20.108
PING 192.168.20.108 (192.168.20.108) 8000(8028) bytes of data.
8008 bytes from 192.168.20.108: icmp_seq=2 ttl=64 time=0.322 ms

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-14 00:47:54 -05:00
David S. Miller 045f7b3b00 neigh: Kill bogus SMP protected debugging message.
Whatever situations make this state legitimate when SMP
also would be legitimate when !SMP and f.e. preemption is
enabled.

This is dubious enough that we should just delete it entirely.  If we
want to add debugging for neigh timer races, better more thorough
mechanisms are needed.

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-01 17:45:55 -04:00
roy.qing.li@gmail.com e049f28883 neigh: fix rcu splat in neigh_update()
when use dst_get_neighbour to get neighbour, we need
rcu_read_lock to protect, since dst_get_neighbour uses
rcu_dereference.

The bug was reported by Ari Savolainen <ari.m.savolainen@gmail.com>

[  105.612095]
[  105.612096] ===================================================
[  105.612100] [ INFO: suspicious rcu_dereference_check() usage. ]
[  105.612101] ---------------------------------------------------
[  105.612103] include/net/dst.h:91 invoked rcu_dereference_check()
without protection!
[  105.612105]
[  105.612106] other info that might help us debug this:
[  105.612106]
[  105.612108]
[  105.612108] rcu_scheduler_active = 1, debug_locks = 0
[  105.612110] 1 lock held by dnsmasq/2618:
[  105.612111]  #0:  (rtnl_mutex){+.+.+.}, at: [<ffffffff815df8c7>]
rtnl_lock+0x17/0x20
[  105.612120]
[  105.612121] stack backtrace:
[  105.612123] Pid: 2618, comm: dnsmasq Not tainted 3.1.0-rc1 #41
[  105.612125] Call Trace:
[  105.612129]  [<ffffffff810ccdcb>] lockdep_rcu_dereference+0xbb/0xc0
[  105.612132]  [<ffffffff815dc5a9>] neigh_update+0x4f9/0x5f0
[  105.612135]  [<ffffffff815da001>] ? neigh_lookup+0xe1/0x220
[  105.612139]  [<ffffffff81639298>] arp_req_set+0xb8/0x230
[  105.612142]  [<ffffffff8163a59f>] arp_ioctl+0x1bf/0x310
[  105.612146]  [<ffffffff810baa40>] ? lock_hrtimer_base.isra.26+0x30/0x60
[  105.612150]  [<ffffffff8163fb75>] inet_ioctl+0x85/0x90
[  105.612154]  [<ffffffff815b5520>] sock_do_ioctl+0x30/0x70
[  105.612157]  [<ffffffff815b55d3>] sock_ioctl+0x73/0x280
[  105.612162]  [<ffffffff811b7698>] do_vfs_ioctl+0x98/0x570
[  105.612165]  [<ffffffff811a5c40>] ? fget_light+0x340/0x3a0
[  105.612168]  [<ffffffff811b7bbf>] sys_ioctl+0x4f/0x80
[  105.612172]  [<ffffffff816fdcab>] system_call_fastpath+0x16/0x1b

Reported-by: Ari Savolainen <ari.m.savolainen@gmail.com>
Signed-off-by: RongQing <roy.qing.li@gmail.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-10-19 19:38:51 -04:00