Commit graph

81 commits

Author SHA1 Message Date
Al Viro
d3bc23e7ee [NET]: Annotate callers of csum_fold() in net/*
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02 21:23:27 -08:00
Al Viro
252e33467a [NET] net/core: Annotations.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02 21:22:49 -08:00
Adrian Bunk
90833aa4f4 [NET]: The scheduled removal of the frame diverter.
This patch contains the scheduled removal of the frame diverter.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02 21:22:23 -08:00
Stephen Hemminger
88041b79f8 [PATCH] netdev: don't allow register_netdev with blank name
This bit of old backwards compatibility cruft can be removed in 2.6.20.
If there is still an device that calls register_netdev()
with a zero or blank name, it will get -EINVAL from register_netdevice().

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2006-12-02 00:16:37 -05:00
Stephen Hemminger
aaa248f6c9 [PATCH] rename net_random to random32
Make net_random() more widely available by calling it random32

akpm: hopefully this will permit the removal of carta_random32.  That needs
confirmation from Stephane - this code looks somewhat more computationally
expensive, and has a different (ie: callee-stateful) interface.

[akpm@osdl.org: lots of build fixes, cleanups]
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Cc: Stephane Eranian <eranian@hpl.hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-17 08:18:43 -07:00
Patrick McHardy
85670cc1fa [NET_SCHED]: Fix fallout from dev->qdisc RCU change
The move of qdisc destruction to a rcu callback broke locking in the
entire qdisc layer by invalidating previously valid assumptions about
the context in which changes to the qdisc tree occur.

The two assumptions were:

- since changes only happen in process context, read_lock doesn't need
  bottem half protection. Now invalid since destruction of inner qdiscs,
  classifiers, actions and estimators happens in the RCU callback unless
  they're manually deleted, resulting in dead-locks when read_lock in
  process context is interrupted by write_lock_bh in bottem half context.

- since changes only happen under the RTNL, no additional locking is
  necessary for data not used during packet processing (f.e. u32_list).
  Again, since destruction now happens in the RCU callback, this assumption
  is not valid anymore, causing races while using this data, which can
  result in corruption or use-after-free.

Instead of "fixing" this by disabling bottem halfs everywhere and adding
new locks/refcounting, this patch makes these assumptions valid again by
moving destruction back to process context. Since only the dev->qdisc
pointer is protected by RCU, but ->enqueue and the qdisc tree are still
protected by dev->qdisc_lock, destruction of the tree can be performed
immediately and only the final free needs to happen in the rcu callback
to make sure dev_queue_xmit doesn't access already freed memory.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-28 18:01:50 -07:00
Stephen Hemminger
b6fe17d6cc [NET] netdev: Check name length
Some improvements to robust name interface.  These API's are safe
now by convention, but it is worth providing some safety checks
against future bugs.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22 14:54:35 -07:00
Patrick McHardy
84fa7933a3 [NET]: Replace CHECKSUM_HW by CHECKSUM_PARTIAL/CHECKSUM_COMPLETE
Replace CHECKSUM_HW by CHECKSUM_PARTIAL (for outgoing packets, whose
checksum still needs to be completed) and CHECKSUM_COMPLETE (for
incoming packets, device supplied full checksum).

Patch originally from Herbert Xu, updated by myself for 2.6.18-rc3.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22 14:53:53 -07:00
David S. Miller
c7fa9d189e [NET]: Disallow whitespace in network device names.
It causes way too much trouble and confusion in userspace.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-08-17 16:29:56 -07:00
David S. Miller
7ea49ed73c [VLAN]: Make sure bonding packet drop checks get done in hwaccel RX path.
Since __vlan_hwaccel_rx() is essentially bypassing the
netif_receive_skb() call that would have occurred if we did the VLAN
decapsulation in software, we are missing the skb_bond() call and the
assosciated checks it does.

Export those checks via an inline function, skb_bond_should_drop(),
and use this in __vlan_hwaccel_rx().

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-08-17 16:29:46 -07:00
Alexey Dobriyan
29bbd72d6e [NET]: Fix more per-cpu typos
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-08-02 15:02:31 -07:00
Chris Leech
e6eb307d48 [I/OAT]: Remove CPU hotplug lock from net_dma_rebalance
Remove the lock_cpu_hotplug()/unlock_cpu_hotplug() calls from
net_dma_rebalance

The lock_cpu_hotplug()/unlock_cpu_hotplug() sequence in
net_dma_rebalance is both incorrect (as pointed out by David Miller)
because lock_cpu_hotplug() may sleep while the net_dma_event_lock
spinlock is held, and unnecessary (as pointed out by Andrew Morton) as
spin_lock() disables preemption which protects from CPU hotplug
events.

Signed-off-by: Chris Leech <christopher.leech@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-08-02 14:21:19 -07:00
David S. Miller
b60dfc6c20 [NET]: Kill the WARN_ON() calls for checksum fixups.
We have a more complete solution in the works, involving
the seperation of CHECKSUM_HW on input vs. output, and
having netfilter properly do incremental checksums.

But that is a very involved patch and is thus 2.6.19
material.

What we have now is infinitely better than the past,
wherein all TSO packets were dropped due to corrupt
checksums as soon at the NAT module was loaded.  At
least now, the checksums do get fixed up, it just
isn't the cleanest nor most optimal solution.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-08-02 13:38:30 -07:00
Herbert Xu
a430a43d08 [NET] gso: Fix up GSO packets with broken checksums
Certain subsystems in the stack (e.g., netfilter) can break the partial
checksum on GSO packets.  Until they're fixed, this patch allows this to
work by recomputing the partial checksums through the GSO mechanism.

Once they've all been converted to update the partial checksum instead of
clearing it, this workaround can be removed.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-07-08 13:34:56 -07:00
Stephen Hemminger
5a8da02ba5 [NET]: Fix network device interface printk message priority
The printk's in the network device interface code should all be tagged
with severity.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-07-07 16:54:05 -07:00
Jörn Engel
6ab3d5624e Remove obsolete #include <linux/config.h>
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-06-30 19:25:36 +02:00
Herbert Xu
3d3a853379 [NET]: Make illegal_highdma more anal
Rather than having illegal_highdma as a macro when HIGHMEM is off, we
can turn it into an inline function that returns zero.  This will catch
callers that give it bad arguments.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-29 16:57:59 -07:00
Herbert Xu
576a30eb64 [NET]: Added GSO header verification
When GSO packets come from an untrusted source (e.g., a Xen guest domain),
we need to verify the header integrity before passing it to the hardware.

Since the first step in GSO is to verify the header, we can reuse that
code by adding a new bit to gso_type: SKB_GSO_DODGY.  Packets with this
bit set can only be fed directly to devices with the corresponding bit
NETIF_F_GSO_ROBUST.  If the device doesn't have that bit, then the skb
is fed to the GSO engine which will allow the packet to be sent to the
hardware if it passes the header check.

This patch changes the sg flag to a full features flag.  The same method
can be used to implement TSO ECN support.  We simply have to mark packets
with CWR set with SKB_GSO_ECN so that only hardware with a corresponding
NETIF_F_TSO_ECN can accept them.  The GSO engine can either fully segment
the packet, or segment the first MTU and pass the rest to the hardware for
further segmentation.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-29 16:57:53 -07:00
Adrian Bunk
6048126440 [NET]: make net/core/dev.c:netdev_nit static
netdev_nit can now become static.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-25 23:58:10 -07:00
Michael Chan
f54d9e8d7f [NET]: Fix GSO problems in dev_hard_start_xmit()
Fix 2 problems in dev_hard_start_xmit():

1. nskb->next needs to link back to skb->next if hard_start_xmit()
returns non-zero.

2. Since the total number of GSO fragments may exceed MAX_SKB_FRAGS + 1,
it needs to stop transmitting if the netif_queue is stopped.

Signed-off-by: Michael Chan <mchan@broadcom.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-25 23:57:04 -07:00
Linus Torvalds
199f4c9f76 Merge master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
* master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6:
  [NET]: Require CAP_NET_ADMIN to create tuntap devices.
  [NET]: fix net-core kernel-doc
  [TCP]: Move inclusion of <linux/dmaengine.h> to correct place in <linux/tcp.h>
  [IPSEC]: Handle GSO packets
  [NET]: Added GSO toggle
  [NET]: Add software TSOv4
  [NET]: Add generic segmentation offload
  [NET]: Merge TSO/UFO fields in sk_buff
  [NET]: Prevent transmission after dev_deactivate
  [IPV6] ADDRCONF: Fix default source address selection without CONFIG_IPV6_PRIVACY
  [IPV6]: Fix source address selection.
  [NET]: Avoid allocating skb in skb_pad
2006-06-23 08:00:01 -07:00
Oleg Nesterov
626ab0e69d [PATCH] list: use list_replace_init() instead of list_splice_init()
list_splice_init(list, head) does unneeded job if it is known that
list_empty(head) == 1.  We can use list_replace_init() instead.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:43:07 -07:00
Randy Dunlap
f4b8ea7849 [NET]: fix net-core kernel-doc
Warning(/var/linsrc/linux-2617-g4//include/linux/skbuff.h:304): No description found for parameter 'dma_cookie'
Warning(/var/linsrc/linux-2617-g4//include/net/sock.h:1274): No description found for parameter 'copied_early'
Warning(/var/linsrc/linux-2617-g4//net/core/dev.c:3309): No description found for parameter 'chan'
Warning(/var/linsrc/linux-2617-g4//net/core/dev.c:3309): No description found for parameter 'event'

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-23 02:07:42 -07:00
Herbert Xu
f6a78bfcb1 [NET]: Add generic segmentation offload
This patch adds the infrastructure for generic segmentation offload.
The idea is to tap into the potential savings of TSO without hardware
support by postponing the allocation of segmented skb's until just
before the entry point into the NIC driver.

The same structure can be used to support software IPv6 TSO, as well as
UFO and segmentation offload for other relevant protocols, e.g., DCCP.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-23 02:07:31 -07:00
Herbert Xu
d4828d85d1 [NET]: Prevent transmission after dev_deactivate
The dev_deactivate function has bit-rotted since the introduction of
lockless drivers.  In particular, the spin_unlock_wait call at the end
has no effect on the xmit routine of lockless drivers.

With a little bit of work, we can make it much more useful by providing
the guarantee that when it returns, no more calls to the xmit routine
of the underlying driver will be made.

The idea is simple.  There are two entry points in to the xmit routine.
The first comes from dev_queue_xmit.  That one is easily stopped by
using synchronize_rcu.  This works because we set the qdisc to noop_qdisc
before the synchronize_rcu call.  That in turn causes all subsequent
packets sent to dev_queue_xmit to be dropped.  The synchronize_rcu call
also ensures all outstanding calls leave their critical section.

The other entry point is from qdisc_run.  Since we now have a bit that
indicates whether it's running, all we have to do is to wait until the
bit is off.

I've removed the loop to wait for __LINK_STATE_SCHED to clear.  This is
useless because netif_wake_queue can cause it to be set again.  It is
also harmless because we've disarmed qdisc_run.

I've also removed the spin_unlock_wait on xmit_lock because its only
purpose of making sure that all outstanding xmit_lock holders have
exited is also given by dev_watchdog_down.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-23 02:07:26 -07:00
Herbert Xu
8648b3053b [NET]: Add NETIF_F_GEN_CSUM and NETIF_F_ALL_CSUM
The current stack treats NETIF_F_HW_CSUM and NETIF_F_NO_CSUM
identically so we test for them in quite a few places.  For the sake
of brevity, I'm adding the macro NETIF_F_GEN_CSUM for these two.  We
also test the disjunct of NETIF_F_IP_CSUM and the other two in various
places, for that purpose I've added NETIF_F_ALL_CSUM.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-17 22:06:05 -07:00
Herbert Xu
364c6badde [NET]: Clean up skb_linearize
The linearisation operation doesn't need to be super-optimised.  So we can
replace __skb_linearize with __pskb_pull_tail which does the same thing but
is more general.

Also, most users of skb_linearize end up testing whether the skb is linear
or not so it helps to make skb_linearize do just that.

Some callers of skb_linearize also use it to copy cloned data, so it's
useful to have a new function skb_linearize_cow to copy the data if it's
either non-linear or cloned.

Last but not least, I've removed the gfp argument since nobody uses it
anymore.  If it's ever needed we can easily add it back.

Misc bugs fixed by this patch:

* via-velocity error handling (also, no SG => no frags)

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-17 21:30:16 -07:00
Herbert Xu
932ff279a4 [NET]: Add netif_tx_lock
Various drivers use xmit_lock internally to synchronise with their
transmission routines.  They do so without setting xmit_lock_owner.
This is fine as long as netpoll is not in use.

With netpoll it is possible for deadlocks to occur if xmit_lock_owner
isn't set.  This is because if a printk occurs while xmit_lock is held
and xmit_lock_owner is not set can cause netpoll to attempt to take
xmit_lock recursively.

While it is possible to resolve this by getting netpoll to use
trylock, it is suboptimal because netpoll's sole objective is to
maximise the chance of getting the printk out on the wire.  So
delaying or dropping the message is to be avoided as much as possible.

So the only alternative is to always set xmit_lock_owner.  The
following patch does this by introducing the netif_tx_lock family of
functions that take care of setting/unsetting xmit_lock_owner.

I renamed xmit_lock to _xmit_lock to indicate that it should not be
used directly.  I didn't provide irq versions of the netif_tx_lock
functions since xmit_lock is meant to be a BH-disabling lock.

This is pretty much a straight text substitution except for a small
bug fix in winbond.  It currently uses
netif_stop_queue/spin_unlock_wait to stop transmission.  This is
unsafe as an IRQ can potentially wake up the queue.  So it is safer to
use netif_tx_disable.

The hamradio bits used spin_lock_irq but it is unnecessary as
xmit_lock must never be taken in an IRQ handler.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-17 21:30:14 -07:00
Chris Leech
db21733488 [I/OAT]: Setup the networking subsystem as a DMA client
Attempts to allocate per-CPU DMA channels

Signed-off-by: Chris Leech <christopher.leech@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-17 21:24:58 -07:00
Stephen Hemminger
3041a06909 [NET]: dev.c comment fixes
Noticed that dev_alloc_name() comment was incorrect, and more spellung
errors.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-05-26 13:25:24 -07:00
Stephen Hemminger
b17a7c179d [NET]: Do sysfs registration as part of register_netdevice.
The last step of netdevice registration was being done by a delayed
call, but because it was delayed, it was impossible to return any error
code if the class_device registration failed.

Side effects:
 * one state in registration process is unnecessary.
 * register_netdevice can sleep inside class_device registration/hotplug
 * code in netdev_run_todo only does unregistration so it is simpler.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-05-10 13:21:17 -07:00
Alan Stern
f07d5b9465 [NET]: Make netdev_chain a raw notifier.
From: Alan Stern <stern@rowland.harvard.edu>

This chain does it's own locking via the RTNL semaphore, and
can also run recursively so adding a new mutex here was causing
deadlocks.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-05-09 15:23:03 -07:00
Stephen Hemminger
fe9925b551 [NET]: Create netdev attribute_groups with class_device_add
Atomically create attributes when class device is added. This avoids
the race between registering class_device (which generates hotplug
event), and the creation of attribute groups.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-05-06 17:56:03 -07:00
Jean Tourrilhes
a417016d1a [PATCH] wext: Fix IWENCODEEXT security permissions
Check the permissions when user-space try to read the
encryption parameters via SIOCGIWENCODEEXT. This is trivial and
probably should go in 2.6.17...
	Bug was found by Brian Eaton <eaton.lists@gmail.com>, thanks !

Signed-off-by: Jean Tourrilhes <jt@hpl.hp.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2006-04-19 17:25:38 -04:00
KAMEZAWA Hiroyuki
6f91204225 [PATCH] for_each_possible_cpu: network codes
for_each_cpu() actually iterates across all possible CPUs.  We've had mistakes
in the past where people were using for_each_cpu() where they should have been
iterating across only online or present CPUs.  This is inefficient and
possibly buggy.

We're renaming for_each_cpu() to for_each_possible_cpu() to avoid this in the
future.

This patch replaces for_each_cpu with for_each_possible_cpu under /net

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-04-11 06:18:31 -07:00
Sergey Vlasov
9469d458b9 [NET]: Fix hotplug race during device registration.
From: Thomas de Grenier de Latour <degrenier@easyconnect.fr>

On Sun, 9 Apr 2006 21:56:59 +0400,
Sergey Vlasov <vsu@altlinux.ru> wrote:

> However, show_address() does not output anything unless
> dev->reg_state == NETREG_REGISTERED - and this state is set by
> netdev_run_todo() only after netdev_register_sysfs() returns, so in
> the meantime (while netdev_register_sysfs() is busy adding the
> "statistics" attribute group) some process may see an empty "address"
> attribute.

I've tried the attached patch, suggested by Sergey Vlasov on
hotplug-devel@, and as far as i can test it works just fine.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-04-09 22:32:48 -07:00
Paolo 'Blaisorblade' Giarrusso
31380de95c [NET] kzalloc: use in alloc_netdev
Noticed this use, fixed it.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-04-09 22:25:47 -07:00
Denis Vlasenko
56079431b6 [NET]: Deinline some larger functions from netdevice.h
On a allyesconfig'ured kernel:

Size  Uses Wasted Name and definition
===== ==== ====== ================================================
   95  162  12075 netif_wake_queue      include/linux/netdevice.h
  129   86   9265 dev_kfree_skb_any     include/linux/netdevice.h
  127   56   5885 netif_device_attach   include/linux/netdevice.h
   73   86   4505 dev_kfree_skb_irq     include/linux/netdevice.h
   46   60   1534 netif_device_detach   include/linux/netdevice.h
  119   16   1485 __netif_rx_schedule   include/linux/netdevice.h
  143    5    492 netif_rx_schedule     include/linux/netdevice.h
   81    7    366 netif_schedule        include/linux/netdevice.h

netif_wake_queue is big because __netif_schedule is a big inline:

static inline void __netif_schedule(struct net_device *dev)
{
        if (!test_and_set_bit(__LINK_STATE_SCHED, &dev->state)) {
                unsigned long flags;
                struct softnet_data *sd;

                local_irq_save(flags);
                sd = &__get_cpu_var(softnet_data);
                dev->next_sched = sd->output_queue;
                sd->output_queue = dev;
                raise_softirq_irqoff(NET_TX_SOFTIRQ);
                local_irq_restore(flags);
        }
}

static inline void netif_wake_queue(struct net_device *dev)
{
#ifdef CONFIG_NETPOLL_TRAP
        if (netpoll_trap())
                return;
#endif
        if (test_and_clear_bit(__LINK_STATE_XOFF, &dev->state))
                __netif_schedule(dev);
}

By de-inlining __netif_schedule we are saving a lot of text
at each callsite of netif_wake_queue and netif_schedule.
__netif_rx_schedule is also big, and it makes more sense to keep
both of them out of line.

Patch also deinlines dev_kfree_skb_any. We can deinline dev_kfree_skb_irq
instead... oh well.

netif_device_attach/detach are not hot paths, we can deinline them too.

Signed-off-by: Denis Vlasenko <vda@ilport.com.ua>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-29 15:57:29 -08:00
Alan Stern
e041c68341 [PATCH] Notifier chain update: API changes
The kernel's implementation of notifier chains is unsafe.  There is no
protection against entries being added to or removed from a chain while the
chain is in use.  The issues were discussed in this thread:

    http://marc.theaimsgroup.com/?l=linux-kernel&m=113018709002036&w=2

We noticed that notifier chains in the kernel fall into two basic usage
classes:

	"Blocking" chains are always called from a process context
	and the callout routines are allowed to sleep;

	"Atomic" chains can be called from an atomic context and
	the callout routines are not allowed to sleep.

We decided to codify this distinction and make it part of the API.  Therefore
this set of patches introduces three new, parallel APIs: one for blocking
notifiers, one for atomic notifiers, and one for "raw" notifiers (which is
really just the old API under a new name).  New kinds of data structures are
used for the heads of the chains, and new routines are defined for
registration, unregistration, and calling a chain.  The three APIs are
explained in include/linux/notifier.h and their implementation is in
kernel/sys.c.

With atomic and blocking chains, the implementation guarantees that the chain
links will not be corrupted and that chain callers will not get messed up by
entries being added or removed.  For raw chains the implementation provides no
guarantees at all; users of this API must provide their own protections.  (The
idea was that situations may come up where the assumptions of the atomic and
blocking APIs are not appropriate, so it should be possible for users to
handle these things in their own way.)

There are some limitations, which should not be too hard to live with.  For
atomic/blocking chains, registration and unregistration must always be done in
a process context since the chain is protected by a mutex/rwsem.  Also, a
callout routine for a non-raw chain must not try to register or unregister
entries on its own chain.  (This did happen in a couple of places and the code
had to be changed to avoid it.)

Since atomic chains may be called from within an NMI handler, they cannot use
spinlocks for synchronization.  Instead we use RCU.  The overhead falls almost
entirely in the unregister routine, which is okay since unregistration is much
less frequent that calling a chain.

Here is the list of chains that we adjusted and their classifications.  None
of them use the raw API, so for the moment it is only a placeholder.

  ATOMIC CHAINS
  -------------
arch/i386/kernel/traps.c:		i386die_chain
arch/ia64/kernel/traps.c:		ia64die_chain
arch/powerpc/kernel/traps.c:		powerpc_die_chain
arch/sparc64/kernel/traps.c:		sparc64die_chain
arch/x86_64/kernel/traps.c:		die_chain
drivers/char/ipmi/ipmi_si_intf.c:	xaction_notifier_list
kernel/panic.c:				panic_notifier_list
kernel/profile.c:			task_free_notifier
net/bluetooth/hci_core.c:		hci_notifier
net/ipv4/netfilter/ip_conntrack_core.c:	ip_conntrack_chain
net/ipv4/netfilter/ip_conntrack_core.c:	ip_conntrack_expect_chain
net/ipv6/addrconf.c:			inet6addr_chain
net/netfilter/nf_conntrack_core.c:	nf_conntrack_chain
net/netfilter/nf_conntrack_core.c:	nf_conntrack_expect_chain
net/netlink/af_netlink.c:		netlink_chain

  BLOCKING CHAINS
  ---------------
arch/powerpc/platforms/pseries/reconfig.c:	pSeries_reconfig_chain
arch/s390/kernel/process.c:		idle_chain
arch/x86_64/kernel/process.c		idle_notifier
drivers/base/memory.c:			memory_chain
drivers/cpufreq/cpufreq.c		cpufreq_policy_notifier_list
drivers/cpufreq/cpufreq.c		cpufreq_transition_notifier_list
drivers/macintosh/adb.c:		adb_client_list
drivers/macintosh/via-pmu.c		sleep_notifier_list
drivers/macintosh/via-pmu68k.c		sleep_notifier_list
drivers/macintosh/windfarm_core.c	wf_client_list
drivers/usb/core/notify.c		usb_notifier_list
drivers/video/fbmem.c			fb_notifier_list
kernel/cpu.c				cpu_chain
kernel/module.c				module_notify_list
kernel/profile.c			munmap_notifier
kernel/profile.c			task_exit_notifier
kernel/sys.c				reboot_notifier_list
net/core/dev.c				netdev_chain
net/decnet/dn_dev.c:			dnaddr_chain
net/ipv4/devinet.c:			inetaddr_chain

It's possible that some of these classifications are wrong.  If they are,
please let us know or submit a patch to fix them.  Note that any chain that
gets called very frequently should be atomic, because the rwsem read-locking
used for blocking chains is very likely to incur cache misses on SMP systems.
(However, if the chain's callout routines may sleep then the chain cannot be
atomic.)

The patch set was written by Alan Stern and Chandra Seetharaman, incorporating
material written by Keith Owens and suggestions from Paul McKenney and Andrew
Morton.

[jes@sgi.com: restructure the notifier chain initialization macros]
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:44:50 -08:00
Linus Torvalds
1b9a391736 Merge branch 'audit.b3' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit-current
* 'audit.b3' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit-current: (22 commits)
  [PATCH] fix audit_init failure path
  [PATCH] EXPORT_SYMBOL patch for audit_log, audit_log_start, audit_log_end and audit_format
  [PATCH] sem2mutex: audit_netlink_sem
  [PATCH] simplify audit_free() locking
  [PATCH] Fix audit operators
  [PATCH] promiscuous mode
  [PATCH] Add tty to syscall audit records
  [PATCH] add/remove rule update
  [PATCH] audit string fields interface + consumer
  [PATCH] SE Linux audit events
  [PATCH] Minor cosmetic cleanups to the code moved into auditfilter.c
  [PATCH] Fix audit record filtering with !CONFIG_AUDITSYSCALL
  [PATCH] Fix IA64 success/failure indication in syscall auditing.
  [PATCH] Miscellaneous bug and warning fixes
  [PATCH] Capture selinux subject/object context information.
  [PATCH] Exclude messages by message type
  [PATCH] Collect more inode information during syscall processing.
  [PATCH] Pass dentry, not just name, in fsnotify creation hooks.
  [PATCH] Define new range of userspace messages.
  [PATCH] Filter rule comparators
  ...

Fixed trivial conflict in security/selinux/hooks.c
2006-03-25 09:24:53 -08:00
Herbert Xu
9f514950bb [NET]: Take RTNL when unregistering notifier
The netdev notifier call chain is currently unregistered without taking
any locks outside the notifier system.  Because the notifier system itself
does not synchronise unregistration with respect to the calling of the
chain, we as its user need to do our own locking.

We are supposed to take the RTNL for all calls to netdev notifiers, so
taking the RTNL should be sufficient to protect it.

The registration path in dev.c already takes the RTNL so it's OK.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-25 01:24:25 -08:00
Arjan van de Ven
4a3e2f711a [NET] sem2mutex: net/
Semaphore to mutex conversion.

The conversion was generated via scripts, and the result was validated
automatically via a script as well.

Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20 22:33:17 -08:00
Stephen Hemminger
8aca8a27d9 [NET]: minor net_rx_action optimization
The functions list_del followed by list_add_tail is equivalent to the
existing inline list_move_tail. list_move_tail avoids unnecessary
_LIST_POISON.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20 22:26:39 -08:00
Stephen Hemminger
6756ae4b4e [NET]: Convert RTNL to mutex.
This patch turns the RTNL from a semaphore to a new 2.6.16 mutex and
gets rid of some of the leftover legacy.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20 22:23:58 -08:00
Stefan Rompf
b00055aacd [NET] core: add RFC2863 operstate
this patch adds a dormant flag to network devices, RFC2863 operstate derived
from these flags and possibility for userspace interaction. It allows drivers
to signal that a device is unusable for user traffic without disabling
queueing (and therefore the possibility for protocol establishment traffic to
flow) and a userspace supplicant (WPA, 802.1X) to mark a device unusable
without changes to the driver.

It is the result of our long discussion. However I must admit that it
represents what Jamal and I agreed on with compromises towards Krzysztof, but
Thomas and Krzysztof still disagree with some parts. Anyway I think it should
be applied.

Signed-off-by: Stefan Rompf <stefan@loplof.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20 17:09:11 -08:00
Steve Grubb
5bdb988680 [PATCH] promiscuous mode
Hi,

When a network interface goes into promiscuous mode, its an important security
issue. The attached patch is intended to capture that action and send an
event to the audit system.

The patch carves out a new block of numbers for kernel detected anomalies.
These are events that may indicate suspicious activity. Other examples of
potential kernel anomalies would be: exceeding disk quota, rlimit violations,
changes to syscall entry table.

Signed-off-by: Steve Grubb <sgrubb@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2006-03-20 14:08:55 -05:00
Jay Vosburgh
8f903c708f [PATCH] bonding: suppress duplicate packets
Originally submitted by Kenzo Iwami; his original description is:

The current bonding driver receives duplicate packets when broadcast/
multicast packets are sent by other devices or packets are flooded by the
switch. In this patch, new flags are added in priv_flags of net_device
structure to let the bonding driver discard duplicate packets in
dev.c:skb_bond().

	Modified by Jay Vosburgh to change a define name, update some
comments, rearrange the new skb_bond() for clarity, clear all bonding
priv_flags on slave release, and update the driver version.

Signed-off-by: Kenzo Iwami <k-iwami@cj.jp.nec.com>
Signed-off-by: Jay Vosburgh <fubar@us.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2006-03-03 20:58:00 -05:00
Jeff Garzik
3c9b3a8575 Merge branch 'master' 2006-02-07 01:47:12 -05:00
Eric Dumazet
88a2a4ac6b [PATCH] percpu data: only iterate over possible CPUs
percpu_data blindly allocates bootmem memory to store NR_CPUS instances of
cpudata, instead of allocating memory only for possible cpus.

As a preparation for changing that, we need to convert various 0 -> NR_CPUS
loops to use for_each_cpu().

(The above only applies to users of asm-generic/percpu.h.  powerpc has gone it
alone and is presently only allocating memory for present CPUs, so it's
currently corrupting memory).

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Jens Axboe <axboe@suse.de>
Cc: Anton Blanchard <anton@samba.org>
Acked-by: William Irwin <wli@holomorphy.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-05 11:06:51 -08:00
Adrian Bunk
d86b5e0e6b [PATCH] net/: fix the WIRELESS_EXT abuse
This patch contains the following changes:
- add a CONFIG_WIRELESS_EXT select'ed by NET_RADIO for conditional
  code
- remove the now no longer required #ifdef CONFIG_NET_RADIO from some
  #include's

Based on a patch by Jean Tourrilhes <jt@hpl.hp.com>.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2006-01-30 20:35:30 -05:00