Commit Graph

138 Commits

Author SHA1 Message Date
Phil Oester
97c802a113 [NETFILTER]: xt_string: fix negation
The xt_string match is broken with ! negation.
This resolves a portion of netfilter bugzilla #497.

Signed-off-by: Phil Oester <kernel@linuxace.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-08-13 18:05:35 -07:00
Patrick McHardy
3ab720881b [NETFILTER]: xt_hashlimit/xt_string: missing string validation
The hashlimit table name and the textsearch algorithm need to be
terminated, the textsearch pattern length must not exceed the
maximum size.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-08-02 13:38:29 -07:00
James Morris
a280b89982 [SECURITY] secmark: nul-terminate secdata
The patch below fixes a problem in the iptables SECMARK target, where
the user-supplied 'selctx' string may not be nul-terminated.

From initial analysis, it seems that the strlen() called from
selinux_string_to_sid() could run until it arbitrarily finds a zero,
and possibly cause a kernel oops before then.

The impact of this appears limited because the operation requires
CAP_NET_ADMIN, which is essentially always root.  Also, the module is
not yet in wide use.

Signed-off-by: James Morris <jmorris@namei.org>
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-08-02 13:38:23 -07:00
Patrick McHardy
d5af981e93 [NETFILTER]: Demote xt_sctp to EXPERIMENTAL
After the recent problems with all the SCTP stuff it seems reasonable
to mark this as experimental.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-07-24 22:55:29 -07:00
Patrick McHardy
10ea6ac895 [NETFILTER]: bridge netfilter: add deferred output hooks to feature-removal-schedule
Add bridge netfilter deferred output hooks to feature-removal-schedule
and disable them by default. Until their removal they will be
activated by the physdev match when needed.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-07-24 22:54:55 -07:00
Phil Oester
28658c8967 [NETFILTER]: xt_pkttype: fix mismatches on locally generated packets
Locally generated broadcast and multicast packets have pkttype set to
PACKET_LOOPBACK instead of PACKET_BROADCAST or PACKET_MULTICAST. This
causes the pkttype match to fail to match packets of either type.

The below patch remedies this by using the daddr as a hint as to
broadcast|multicast. While not pretty, this seems like the only way
to solve the problem short of just noting this as a limitation of the
match.

This resolves netfilter bugzilla #484

Signed-off-by: Phil Oester <kernel@linuxace.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-07-24 22:54:14 -07:00
Adrian Bunk
72b5582359 [NETFILTER]: conntrack: fix SYSCTL=n compile
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-07-24 22:53:12 -07:00
Patrick McHardy
3bc38712e3 [NETFILTER]: nf_queue: handle NF_STOP and unknown verdicts in nf_reinject
In case of an unknown verdict or NF_STOP the packet leaks. Unknown verdicts
can happen when userspace is buggy. Reinject the packet in case of NF_STOP,
drop on unknown verdicts.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-07-24 22:52:47 -07:00
Linus Torvalds
e37a72de84 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:
  [IPV6]: Added GSO support for TCPv6
  [NET]: Generalise TSO-specific bits from skb_setup_caps
  [IPV6]: Added GSO support for TCPv6
  [IPV6]: Remove redundant length check on input
  [NETFILTER]: SCTP conntrack: fix crash triggered by packet without chunks
  [TG3]: Update version and reldate
  [TG3]: Add TSO workaround using GSO
  [TG3]: Turn on hw fix for ASF problems
  [TG3]: Add rx BD workaround
  [TG3]: Add tg3_netif_stop() in vlan functions
  [TCP]: Reset gso_segs if packet is dodgy
2006-06-30 15:40:17 -07:00
Patrick McHardy
dd7271feba [NETFILTER]: SCTP conntrack: fix crash triggered by packet without chunks
When a packet without any chunks is received, the newconntrack variable
in sctp_packet contains an out of bounds value that is used to look up an
pointer from the array of timeouts, which is then dereferenced, resulting
in a crash. Make sure at least a single chunk is present.

Problem noticed by George A. Theall <theall@tenablesecurity.com>

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-30 14:12:01 -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
Darrel Goeddel
c7bdb545d2 [NETLINK]: Encapsulate eff_cap usage within security framework.
This patch encapsulates the usage of eff_cap (in netlink_skb_params) within
the security framework by extending security_netlink_recv to include a required
capability parameter and converting all direct usage of eff_caps outside
of the lsm modules to use the interface.  It also updates the SELinux
implementation of the security_netlink_send and security_netlink_recv
hooks to take advantage of the sid in the netlink_skb_params struct.
This also enables SELinux to perform auditing of netlink capability checks.
Please apply, for 2.6.18 if possible.

Signed-off-by: Darrel Goeddel <dgoeddel@trustedcs.com>
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by:  James Morris <jmorris@namei.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-29 16:57:55 -07:00
Patrick McHardy
68c1692e3e [NETFILTER]: statistic match: add missing Kconfig help text
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-29 16:57:50 -07:00
Patrick McHardy
ef47c6a7b8 [NETFILTER]: ip_queue/nfnetlink_queue: drop bridge port references when dev disappears
When a device that is acting as a bridge port is unregistered, the
ip_queue/nfnetlink_queue notifier doesn't check if its one of
physindev/physoutdev and doesn't release the references if it is.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-29 16:57:48 -07:00
Jorge Matias
1c7e47726a [NETFILTER]: xt_sctp: fix --chunk-types matching
xt_sctp uses an incorrect header offset when --chunk-types is used.

Signed-off-by: Jorge Matias <jorge.matias@motorola.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-29 16:57:46 -07:00
Yuri Gushin
9abdcf6b6c [NETFILTER]: xt_tcpudp: fix double unregistration in error path
"xt_unregister_match(AF_INET, &tcp_matchstruct)" is called twice,
leaving "udp_matchstruct" registered, in case of a failure in the
registration of the udp6 structure.

Signed-off-by: Yuri Gushin <yuri@ecl-labs.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-29 16:57:44 -07:00
Yasuyuki Kozakai
40a839fdbd [NETFILTER]: nf_conntrack: Fix undefined references to local_bh_*
CC      net/netfilter/nf_conntrack_proto_sctp.o
net/netfilter/nf_conntrack_proto_sctp.c: In function `sctp_print_conntrack':
net/netfilter/nf_conntrack_proto_sctp.c:206: warning: implicit declaration of function `local_bh_disable'
net/netfilter/nf_conntrack_proto_sctp.c:208: warning: implicit declaration of function `local_bh_enable'
  CC      net/netfilter/nf_conntrack_netlink.o
net/netfilter/nf_conntrack_netlink.c: In function `ctnetlink_dump_table':
net/netfilter/nf_conntrack_netlink.c:429: warning: implicit declaration of function `local_bh_disable'
net/netfilter/nf_conntrack_netlink.c:452: warning: implicit declaration of function `local_bh_enable'

Spotted by Toralf Förster

Signed-off-by: Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-29 16:57:42 -07:00
Patrick McHardy
d3dcd4efe2 [NETFILTER]: xt_sctp: fix endless loop caused by 0 chunk length
Fix endless loop in the SCTP match similar to those already fixed in
the SCTP conntrack helper (was CVE-2006-1527).

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-19 23:39:45 -07:00
James Morris
100468e9c0 [SECMARK]: Add CONNSECMARK xtables target
Add a new xtables target, CONNSECMARK, which is used to specify rules
for copying security marks from packets to connections, and for
copyying security marks back from connections to packets.  This is
similar to the CONNMARK target, but is more limited in scope in that
it only allows copying of security marks to and from packets, as this
is all it needs to do.

A typical scenario would be to apply a security mark to a 'new' packet
with SECMARK, then copy that to its conntrack via CONNMARK, and then
restore the security mark from the connection to established and
related packets on that connection.

Signed-off-by: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-17 21:30:03 -07:00
James Morris
7c9728c393 [SECMARK]: Add secmark support to conntrack
Add a secmark field to IP and NF conntracks, so that security markings
on packets can be copied to their associated connections, and also
copied back to packets as required.  This is similar to the network
mark field currently used with conntrack, although it is intended for
enforcement of security policy rather than network policy.

Signed-off-by: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-17 21:30:01 -07:00
James Morris
5e6874cdb8 [SECMARK]: Add xtables SECMARK target
Add a SECMARK target to xtables, allowing the admin to apply security
marks to packets via both iptables and ip6tables.

The target currently handles SELinux security marking, but can be
extended for other purposes as needed.

Signed-off-by: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-17 21:29:59 -07:00
Patrick McHardy
7d8c501817 [NETFILTER]: FTP helper: search optimization
Instead of skipping search entries for the wrong direction simply index
them by direction.

Based on patch by Pablo Neira <pablo@netfilter.org>

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-17 21:29:07 -07:00
Patrick McHardy
89f2e21883 [NETFILTER]: ctnetlink: change table dumping not to require an unique ID
Instead of using the ID to find out where to continue dumping, take a
reference to the last entry dumped and try to continue there.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-17 21:29:03 -07:00
Patrick McHardy
3726add766 [NETFILTER]: ctnetlink: fix NAT configuration
The current configuration only allows to configure one manip and overloads
conntrack status flags with netlink semantic.

Signed-off-by: Patrick Mchardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-17 21:29:01 -07:00
Eric Leblond
997ae831ad [NETFILTER]: conntrack: add fixed timeout flag in connection tracking
Add a flag in a connection status to have a non updated timeout.
This permits to have connection that automatically die at a given
time.

Signed-off-by: Eric Leblond <eric@inl.fr>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-17 21:28:59 -07:00
Patrick McHardy
39a27a35c5 [NETFILTER]: conntrack: add sysctl to disable checksumming
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-17 21:28:57 -07:00
Patrick McHardy
f3389805e5 [NETFILTER]: x_tables: add statistic match
Add statistic match which is a combination of the nth and random matches.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-17 21:28:51 -07:00
Patrick McHardy
62b7743483 [NETFILTER]: x_tables: add quota match
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-17 21:28:49 -07:00
Patrick McHardy
957dc80ac3 [NETFILTER]: x_tables: add SCTP/DCCP support where missing
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-17 21:28:47 -07:00
Patrick McHardy
3e72b2fe5b [NETFILTER]: x_tables: remove some unnecessary casts
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-17 21:28:45 -07:00
Patrick McHardy
ee433530d9 [NETFILTER]: nfnetlink_log: fix byteorder confusion
flags is a u16, so use htons instead of htonl. Also avoid double
conversion.

Noticed by Alexey Dobriyan <adobriyan@gmail.com>

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-05-19 02:17:18 -07:00
Patrick McHardy
7800007c1e [NETFILTER]: x_tables: don't use __copy_{from,to}_user on unchecked memory in compat layer
Noticed by Linus Torvalds <torvalds@osdl.org>

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-05-03 23:20:27 -07:00
Patrick McHardy
e17df688f7 [NETFILTER] SCTP conntrack: fix infinite loop
fix infinite loop in the SCTP-netfilter code: check SCTP chunk size to
guarantee progress of for_each_sctp_chunk(). (all other uses of
for_each_sctp_chunk() are preceded by do_basic_checks(), so this fix
should be complete.)

Based on patch from Ingo Molnar <mingo@elte.hu>

CVE-2006-1527

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-05-02 17:26:39 -07:00
Dmitry Mishin
91536b7ae6 [NETFILTER]: x_tables: move table->lock initialization
xt_table->lock should be initialized before xt_replace_table() call, which
uses it. This patch removes strict requirement that table should define
lock before registering.

Signed-off-by: Dmitry Mishin <dim@openvz.org>
Signed-off-by: Kirill Korotaev <dev@openvz.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-04-24 17:27:33 -07:00
Yasuyuki Kozakai
2c16b774c7 [NETFILTER]: nf_conntrack: kill unused callback init_conntrack
Signed-off-by: Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-04-24 17:27:31 -07:00
Yasuyuki Kozakai
e1bbdebdba [NETFILTER]: nf_conntrack: Fix module refcount dropping too far
If nf_ct_l3proto_find_get() fails to get the refcount of
nf_ct_l3proto_generic, nf_ct_l3proto_put() will drop the refcount
too far.

This gets rid of '.me = THIS_MODULE' of nf_ct_l3proto_generic so that
nf_ct_l3proto_find_get() doesn't try to get refcount of it.
It's OK because its symbol is usable until nf_conntrack.ko is unloaded.

This also kills unnecessary NULL pointer check as well.
__nf_ct_proto_find() allways returns non-NULL pointer.

Signed-off-by: Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-04-24 17:27:28 -07:00
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
Patrick McHardy
96f6bf82ea [NETFILTER]: Convert conntrack/ipt_REJECT to new checksumming functions
Besides removing lots of duplicate code, all converted users benefit
from improved HW checksum error handling. Tested with and without HW
checksums in almost all combinations.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-04-09 22:25:42 -07:00
Patrick McHardy
bce8032ef3 [NETFILTER]: Introduce infrastructure for address family specific operations
Change the queue rerouter intrastructure to a generic usable
infrastructure for address family specific operations as a base for
some cleanups.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-04-09 22:25:40 -07:00
Patrick McHardy
32292a7ff1 [NETFILTER]: Fix section mismatch warnings
Fix section mismatch warnings caused by netfilter's init_or_cleanup
functions used in many places by splitting the init from the cleanup
parts.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-04-09 22:25:34 -07:00
Patrick McHardy
972d1cb142 [NETFILTER]: Add helper functions for mass hook registration/unregistration
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-04-09 22:25:32 -07:00
Dmitry Mishin
2722971cbe [NETFILTER]: iptables 32bit compat layer
This patch extends current iptables compatibility layer in order to get
32bit iptables to work on 64bit kernel. Current layer is insufficient due
to alignment checks both in kernel and user space tools.

Patch is for current net-2.6.17 with addition of move of ipt_entry_{match|
target} definitions to xt_entry_{match|target}.

Signed-off-by: Dmitry Mishin <dim@openvz.org>
Acked-off-by: Kirill Korotaev <dev@openvz.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-04-01 02:25:19 -08:00
Martin Josefsson
e64a70be51 [NETFILTER]: {ip,nf}_conntrack_netlink: fix expectation notifier unregistration
This patch fixes expectation notifier unregistration on module unload to
use ip_conntrack_expect_unregister_notifier(). This bug causes a soft
lockup at the first expectation created after a rmmod ; insmod of this
module.

Should go into -stable as well.

Signed-off-by: Martin Josefsson <gandalf@wlug.westbo.se>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-04-01 02:24:48 -08:00
Martin Josefsson
bcd1e830a5 [NETFILTER]: fix ifdef for connmark support in nf_conntrack_netlink
When ctnetlink was ported from ip_conntrack to nf_conntrack two #ifdef's
for connmark support were left unchanged and this code was never
compiled.

Problem noticed by Daniel De Graaf.

Signed-off-by: Martin Josefsson <gandalf@wlug.westbo.se>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-04-01 02:23:21 -08:00
Yasuyuki Kozakai
a89ecb6a2e [NETFILTER]: x_tables: unify IPv4/IPv6 multiport match
This unifies ipt_multiport and ip6t_multiport to xt_multiport.
As a result, this addes support for inversion and port range match
to IPv6 packets.

Signed-off-by: Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-04-01 02:22:54 -08:00
Yasuyuki Kozakai
dc5ab2faec [NETFILTER]: x_tables: unify IPv4/IPv6 esp match
This unifies ipt_esp and ip6t_esp to xt_esp. Please note that now
a user program needs to specify IPPROTO_ESP as protocol to use esp match
with IPv6. This means that ip6tables requires '-p esp' like iptables.

Signed-off-by: Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-04-01 02:22:30 -08:00
Herbert Xu
dbe5b4aaaf [IPSEC]: Kill unused decap state structure
This patch removes the *_decap_state structures which were previously
used to share state between input/post_input.  This is no longer
needed.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-04-01 00:54:16 -08:00
Andrew Morton
65b4b4e81a [NETFILTER]: Rename init functions.
Every netfilter module uses `init' for its module_init() function and
`fini' or `cleanup' for its module_exit() function.

Problem is, this creates uninformative initcall_debug output and makes
ctags rather useless.

So go through and rename them all to $(filename)_init and
$(filename)_fini.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-28 17:02:48 -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
Ingo Molnar
9e19bb6d7a [NETFILTER] x_table.c: sem2mutex
Semaphore to mutex conversion.

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

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>
2006-03-25 01:41:10 -08:00