Commit Graph

33 Commits

Author SHA1 Message Date
Gleb Smirnoff
ea53792942 Fix races between in_lltable_prefix_free(), lla_lookup(),
llentry_free() and arptimer():

o Use callout_init_rw() for lle timeout, this allows us safely
  disestablish them.
  - This allows us to simplify the arptimer() and make it
    race safe.
o Consistently use ifp->if_afdata_lock to lock access to
  linked lists in the lle hashes.
o Introduce new lle flag LLE_LINKED, which marks an entry that
  is attached to the hash.
  - Use LLE_LINKED to avoid double unlinking via consequent
    calls to llentry_free().
  - Mark lle with LLE_DELETED via |= operation istead of =,
    so that other flags won't be lost.
o Make LLE_ADDREF(), LLE_REMREF() and LLE_FREE_LOCKED() more
  consistent and provide more informative KASSERTs.

The patch is a collaborative work of all submitters and myself.

PR:		kern/165863
Submitted by:	Andrey Zonov <andrey zonov.org>
Submitted by:	Ryan Stone <rysto32 gmail.com>
Submitted by:	Eric van Gyzen <eric_van_gyzen dell.com>
2012-08-02 13:57:49 +00:00
Gleb Smirnoff
b1d86af706 The llentry_update() is used only by flowtable and the latter
always passes NULL pointer to it. Thus, code can be simplified
and function renamed to llentry_alloc() to match rtalloc().
2012-08-02 13:20:44 +00:00
Gleb Smirnoff
b9aee262e5 Some more whitespace cleanup. 2012-08-01 09:00:26 +00:00
Gleb Smirnoff
ea50c13ebe Some style(9) and whitespace changes.
Together with:	Andrey Zonov <andrey zonov.org>
2012-07-31 11:31:12 +00:00
Kip Macy
0fe48d670f A flowtable entry can continue referencing an llentry indefinitely if the entry is repeatedly
referenced within its timeout window. This change clears the LLE_VALID flag when an llentry
is removed from an interface's hash table and adds an extra check to the flowtable code
for the LLE_VALID flag in llentry to avoid retaining and using a stale reference.

Reviewed by:	qingli@
MFC after:	2 weeks
2012-01-26 20:02:40 +00:00
Gleb Smirnoff
94901d5e60 Move arprequest() declaration to if_ether.h. 2012-01-08 13:34:00 +00:00
Qing Li
5b84dc789a The statically configured (permanent) ARP entries are removed when an
interface is brought down, even though the interface address is still
valid. This patch maintains the permanent ARP entries as long as the
interface address (having the same prefix as that of the ARP entries)
is valid.

Reviewed by:	delphij
MFC after:	5 days
2011-05-20 19:12:20 +00:00
Dimitry Andric
3e288e6238 After some off-list discussion, revert a number of changes to the
DPCPU_DEFINE and VNET_DEFINE macros, as these cause problems for various
people working on the affected files.  A better long-term solution is
still being considered.  This reversal may give some modules empty
set_pcpu or set_vnet sections, but these are harmless.

Changes reverted:

------------------------------------------------------------------------
r215318 | dim | 2010-11-14 21:40:55 +0100 (Sun, 14 Nov 2010) | 4 lines

Instead of unconditionally emitting .globl's for the __start_set_xxx and
__stop_set_xxx symbols, only emit them when the set_vnet or set_pcpu
sections are actually defined.

------------------------------------------------------------------------
r215317 | dim | 2010-11-14 21:38:11 +0100 (Sun, 14 Nov 2010) | 3 lines

Apply the STATIC_VNET_DEFINE and STATIC_DPCPU_DEFINE macros throughout
the tree.

------------------------------------------------------------------------
r215316 | dim | 2010-11-14 21:23:02 +0100 (Sun, 14 Nov 2010) | 2 lines

Add macros to define static instances of VNET_DEFINE and DPCPU_DEFINE.
2010-11-22 19:32:54 +00:00
Dimitry Andric
31c6a0037e Apply the STATIC_VNET_DEFINE and STATIC_DPCPU_DEFINE macros throughout
the tree.
2010-11-14 20:38:11 +00:00
Konstantin Belousov
7b3b099e07 Use 'z' modifier for size_t printing. 2010-11-13 11:11:51 +00:00
George V. Neville-Neil
e162ea60d4 Add a queue to hold packets while we await an ARP reply.
When a fast machine first brings up some non TCP networking program
it is quite possible that we will drop packets due to the fact that
only one packet can be held per ARP entry.  This leads to packets
being missed when a program starts or restarts if the ARP data is
not currently in the ARP cache.

This code adds a new sysctl, net.link.ether.inet.maxhold, which defines
a system wide maximum number of packets to be held in each ARP entry.
Up to maxhold packets are queued until an ARP reply is received or
the ARP times out.  The default setting is the old value of 1
which has been part of the BSD networking code since time
immemorial.

Expose the time we hold an incomplete ARP entry by adding
the sysctl net.link.ether.inet.wait, which defaults to 20
seconds, the value used when the new ARP code was added..

Reviewed by:	bz, rpaulo
MFC after: 3 weeks
2010-11-12 22:03:02 +00:00
Bjoern A. Zeeb
fc2bfb3294 lltable_drain() has never been used so far, thus #if 0 it for now.
While touching it add the missing locking to the now disabled code
for the time when we'll resurrect it.

MFC after:	3 days
2010-10-16 18:42:09 +00:00
Gleb Smirnoff
b17f26b00c Don't check malloc(M_WAITOK) result. 2010-07-27 11:56:49 +00:00
Gleb Smirnoff
85011246ac When installing a new ARP entry via 'arp -S', lla_lookup() will
either find an existing entry, or allocate a new one. In the latter
case an entry would have flags, that were supplied as argument to
lla_lookup(). In case of an existing entry, flags aren't modified.

This lead to losing LLE_PUB and/or LLE_PROXY flags.

We should apply these flags either in lla_rt_output() or in the
in.c:in_lltable_lookup(). It seems to me that lla_rt_output() is
a more correct choice.

PR:		kern/148784, kern/146539
Silence from:	qingli, 5 days
2010-07-27 10:05:27 +00:00
Jung-uk Kim
82040afcf3 Fix an obvious typo from r1.1. We were acquiring an exclusive writer lock
regardless of the given flags.

MFC after:	3 days
2010-07-22 18:44:40 +00:00
Bjoern A. Zeeb
becba438d2 Plug reference leaks in the link-layer code ("new-arp") that previously
prevented the link-layer entry from being freed.

In both in.c and in6.c (though that code path seems to be basically dead)
plug a reference leak in case of a pending callout being drained.

In if_ether.c consistently add a reference before resetting the callout
and in case we canceled a pending one remove the reference for that.
In the final case in arptimer, before freeing the expired entry, remove
the reference again and explicitly call callout_stop() to clear the active
flag.

In nd6.c:nd6_free() we are only ever called from the callout function and
thus need to remove the reference there as well before calling into
llentry_free().

In if_llatbl.c when freeing entire tables make sure that in case we cancel
a pending callout to remove the reference as well.

Reviewed by:		qingli (earlier version)
MFC after:		10 days
Problem observed, patch tested by: simon on ipv6gw.f.o,
			Christian Kratzer (ck cksoft.de),
			Evgenii Davidov (dado korolev-net.ru)
PR:			kern/144564
Configurations still affected:	with options FLOWTABLE
2010-04-11 16:04:08 +00:00
Bjoern A. Zeeb
335b943f8e Add ddb support to the "new" link layer code ("new-arp"):
- show all lltables [1] (optional flag to also show the llentries as well)
 - show lltable <struct lltable *>
 - show llentry <struct llentry *>

MFC after:	6 days
2010-03-18 09:09:59 +00:00
Kip Macy
d4121a02c0 - restructure flowtable to support ipv6
- add a name argument to flowtable_alloc for printing with ddb commands
- extend ddb commands to print destination address or 4-tuples
- don't parse ports in ulp header if FL_HASH_ALL is not passed
- add kern_flowtable_insert to enable more generic use of flowtable
  (e.g. system calls for adding entries)
- don't hash loopback addresses
- cleanup whitespace
- keep statistics per-cpu for per-cpu flowtables to avoid cache line contention
- add sysctls to accumulate stats and report aggregate

MFC after:	7 days
2010-03-12 05:03:26 +00:00
Qing Li
c7ab66020f The proxy arp entries could not be added into the system over the
IFF_POINTOPOINT link types. The reason was due to the routing
entry returned from the kernel covering the remote end is of an
interface type that does not support ARP. This patch fixes this
problem by providing a hint to the kernel routing code, which
indicates the prefix route instead of the PPP host route should
be returned to the caller. Since a host route to the local end
point is also added into the routing table, and there could be
multiple such instantiations due to multiple PPP links can be
created with the same local end IP address, this patch also fixes
the loopback route installation failure problem observed prior to
this patch. The reference count of loopback route to local end would
be either incremented or decremented. The first instantiation would
create the entry and the last removal would delete the route entry.

MFC after:	5 days
2009-12-30 21:35:34 +00:00
Marko Zec
38d61195b8 Style fix - break too long a line in two.
Spotted by:	bz
MFC after:	3 days
2009-09-18 09:03:23 +00:00
Marko Zec
989e04112b V_irtualize the lltables list, making ARP and ND reasonably
usable again with options VIMAGE kernels.

Submitted by:	bz (the original version, probably identical to this one)
Reviewed by:	many @ DevSummit Cambridge
MFC after:	3 days
2009-09-17 14:52:15 +00:00
Qing Li
d134008aa0 The addresses that are assigned to the loopback interface
should be part of the kernel routing table.

Reviewed by:	bz
MFC after:	immediately
2009-09-05 20:24:37 +00:00
Qing Li
9452b0d2de This patch fixes the following issues:
- Interface link-local address is not reachable within the
  node that owns the interface, this is due to the mismatch
  in address scope as the result of the installed interface
  address loopback route. Therefore for each interface
  address loopback route, the rt_gateway field (of AF_LINK
  type) will be used to track which interface a given
  address belongs to. This will aid the address source to
  use the proper interface for address scope/zone validation.
- The loopback address is not reachable. The root cause is
  the same as the above.
- Empty nd6 entries are created for the IPv6 loopback addresses
  only for validation reason. Doing so will eliminate as much
  of the special case (loopback addresses) handling code
  as possible, however, these empty nd6 entries should not
  be returned to the userland applications such as the
  "ndp" command.
Since both of the above issues contain common files, these
files are committed together.

Reviewed by:	bz
MFC after:	immediately
2009-09-05 16:43:16 +00:00
Robert Watson
dc56e98f0d Use locks specific to the lltable code, rather than borrow the ifnet
list/index locks, to protect link layer address tables.  This avoids
lock order issues during interface teardown, but maintains the bug that
sysctl copy routines may be called while a non-sleepable lock is held.

Reviewed by:	bz, kmacy
MFC after:	3 days
2009-08-25 09:52:38 +00:00
Robert Watson
77dfcdc445 Rework global locks for interface list and index management, correcting
several critical bugs, including race conditions and lock order issues:

Replace the single rwlock, ifnet_lock, with two locks, an rwlock and an
sxlock.  Either can be held to stablize the lists and indexes, but both
are required to write.  This allows the list to be held stable in both
network interrupt contexts and sleepable user threads across sleeping
memory allocations or device driver interactions.  As before, writes to
the interface list must occur from sleepable contexts.

Reviewed by:	bz, julian
MFC after:	3 days
2009-08-23 20:40:19 +00:00
Robert Watson
530c006014 Merge the remainder of kern_vimage.c and vimage.h into vnet.c and
vnet.h, we now use jails (rather than vimages) as the abstraction
for virtualization management, and what remained was specific to
virtual network stacks.  Minor cleanups are done in the process,
and comments updated to reflect these changes.

Reviewed by:	bz
Approved by:	re (vimage blanket)
2009-08-01 19:26:27 +00:00
Qing Li
c9d763bf41 When an interface address is removed and the last prefix
route is also being deleted, the link-layer address table
(arp or nd6) will flush those L2 llinfo entries that match
the removed prefix.

Reviewed by:	kmacy
2009-05-20 21:07:15 +00:00
Kip Macy
e94ba2ce53 clarify state of llentry that is passed back 2009-04-17 18:48:50 +00:00
Kip Macy
adfc35ff8b add comment to llentry_update
Requested by: sam
2009-04-16 22:55:59 +00:00
Kip Macy
c8da95ace9 add utility routine for updating an struct llentry * 2009-04-16 22:04:07 +00:00
Bjoern A. Zeeb
2e730bea0a Like with r185713 make sure to not leak a lock as rtalloc1(9) returns
a locked route. Thus we have to use RTFREE_LOCKED(9) to get it unlocked
and rtfree(9)d rather than just rtfree(9)d.

Since the PR was filed, new places with the same problem were added
with new code.  Also check that the rt is valid before freeing it
either way there.

PR:		kern/129793
Submitted by:	Dheeraj Reddy <dheeraj@ece.gatech.edu>
MFC after:	2 weeks
Committed from:	Bugathon #6
2009-01-31 10:48:02 +00:00
Kip Macy
7b4d716b62 style and spelling fix 2008-12-16 04:41:39 +00:00
Kip Macy
82f39c9177 Add arpv2 management code 2008-12-15 06:53:09 +00:00