Commit Graph

97 Commits (0221c81b1b8eb0cbb6b30a0ced52ead32d2b4e4c)

Author SHA1 Message Date
Eric Dumazet fa9a86ddc8 netfilter: use rcu_read_bh() in ipt_do_table()
Commit 784544739a
(netfilter: iptables: lock free counters) forgot to disable BH
in arpt_do_table(), ipt_do_table() and  ip6t_do_table()

Use rcu_read_lock_bh() instead of rcu_read_lock() cures the problem.

Reported-and-bisected-by: Roman Mindalev <r000n@r000n.net>
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Acked-by: Patrick McHardy <kaber@trash.net>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-02 00:54:43 -07:00
Patrick McHardy 1f9352ae22 netfilter: {ip,ip6,arp}_tables: fix incorrect loop detection
Commit e1b4b9f ([NETFILTER]: {ip,ip6,arp}_tables: fix exponential worst-case
search for loops) introduced a regression in the loop detection algorithm,
causing sporadic incorrectly detected loops.

When a chain has already been visited during the check, it is treated as
having a standard target containing a RETURN verdict directly at the
beginning in order to not check it again. The real target of the first
rule is then incorrectly treated as STANDARD target and checked not to
contain invalid verdicts.

Fix by making sure the rule does actually contain a standard target.

Based on patch by Francis Dupont <Francis_Dupont@isc.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-03-25 19:26:35 +01:00
Eric Dumazet b8dfe49877 netfilter: factorize ifname_compare()
We use same not trivial helper function in four places. We can factorize it.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-03-25 17:31:52 +01:00
Stephen Hemminger 784544739a netfilter: iptables: lock free counters
The reader/writer lock in ip_tables is acquired in the critical path of
processing packets and is one of the reasons just loading iptables can cause
a 20% performance loss. The rwlock serves two functions:

1) it prevents changes to table state (xt_replace) while table is in use.
   This is now handled by doing rcu on the xt_table. When table is
   replaced, the new table(s) are put in and the old one table(s) are freed
   after RCU period.

2) it provides synchronization when accesing the counter values.
   This is now handled by swapping in new table_info entries for each cpu
   then summing the old values, and putting the result back onto one
   cpu.  On a busy system it may cause sampling to occur at different
   times on each cpu, but no packet/byte counts are lost in the process.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>

Sucessfully tested on my dual quad core machine too, but iptables only (no ipv6 here)
BTW, my new "tbench 8" result is 2450 MB/s, (it was 2150 MB/s not so long ago)

Acked-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-02-20 10:35:32 +01:00
Eric Dumazet 323dbf9638 netfilter: ip6_tables: unfold two loops in ip6_packet_match()
ip6_tables netfilter module can use an ifname_compare() helper
so that two loops are unfolded.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-02-19 11:18:23 +01:00
Jan Engelhardt 916a917dfe netfilter: xtables: provide invoked family value to extensions
By passing in the family through which extensions were invoked, a bit
of data space can be reclaimed. The "family" member will be added to
the parameter structures and the check functions be adjusted.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2008-10-08 11:35:20 +02:00
Jan Engelhardt a2df1648ba netfilter: xtables: move extension arguments into compound structure (6/6)
This patch does this for target extensions' destroy functions.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2008-10-08 11:35:19 +02:00
Jan Engelhardt af5d6dc200 netfilter: xtables: move extension arguments into compound structure (5/6)
This patch does this for target extensions' checkentry functions.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2008-10-08 11:35:19 +02:00
Jan Engelhardt 7eb3558655 netfilter: xtables: move extension arguments into compound structure (4/6)
This patch does this for target extensions' target functions.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2008-10-08 11:35:19 +02:00
Jan Engelhardt 6be3d8598e netfilter: xtables: move extension arguments into compound structure (3/6)
This patch does this for match extensions' destroy functions.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2008-10-08 11:35:19 +02:00
Jan Engelhardt 9b4fce7a35 netfilter: xtables: move extension arguments into compound structure (2/6)
This patch does this for match extensions' checkentry functions.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2008-10-08 11:35:18 +02:00
Jan Engelhardt f7108a20de netfilter: xtables: move extension arguments into compound structure (1/6)
The function signatures for Xtables extensions have grown over time.
It involves a lot of typing/replication, and also a bit of stack space
even if they are not used. Realize an NFWS2008 idea and pack them into
structs. The skb remains outside of the struct so gcc can continue to
apply its optimizations.

This patch does this for match extensions' match functions.

A few ambiguities have also been addressed. The "offset" parameter for
example has been renamed to "fragoff" (there are so many different
offsets already) and "protoff" to "thoff" (there is more than just one
protocol here, so clarify).

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2008-10-08 11:35:18 +02:00
Jan Engelhardt 367c679007 netfilter: xtables: do centralized checkentry call (1/2)
It used to be that {ip,ip6,etc}_tables called extension->checkentry
themselves, but this can be moved into the xtables core.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2008-10-08 11:35:17 +02:00
Patrick McHardy 544473c166 [NETFILTER]: {ip,ip6,arp}_tables: return EAGAIN for invalid SO_GET_ENTRIES size
Rule dumping is performed in two steps: first userspace gets the
ruleset size using getsockopt(SO_GET_INFO) and allocates memory,
then it calls getsockopt(SO_GET_ENTRIES) to actually dump the
ruleset. When another process changes the ruleset in between the
sizes from the first getsockopt call doesn't match anymore and
the kernel aborts. Unfortunately it returns EAGAIN, as for multiple
other possible errors, so userspace can't distinguish this case
from real errors.

Return EAGAIN so userspace can retry the operation.

Fixes (with current iptables SVN version) netfilter bugzilla #104.

Signed-off-by: Patrick McHardy <kaber@trash.net>
2008-04-14 11:15:45 +02:00
Jan Engelhardt 5452e425ad [NETFILTER]: annotate {arp,ip,ip6,x}tables with const
Signed-off-by: Jan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2008-04-14 11:15:35 +02:00
YOSHIFUJI Hideaki 3b1e0a655f [NET] NETNS: Omit sock->sk_net without CONFIG_NET_NS.
Introduce per-sock inlines: sock_net(), sock_net_set()
and per-inet_timewait_sock inlines: twsk_net(), twsk_net_set().
Without CONFIG_NET_NS, no namespace other than &init_net exists.
Let's explicitly define them to help compiler optimizations.

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
2008-03-26 04:39:55 +09:00
Harvey Harrison 0dc47877a3 net: replace remaining __FUNCTION__ occurrences
__FUNCTION__ is gcc-specific, use __func__

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-05 20:47:47 -08:00
Alexey Dobriyan 3cb609d57c [NETFILTER]: x_tables: create per-netns /proc/net/*_tables_*
Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-31 19:28:06 -08:00
Patrick McHardy b0a6363c24 [NETFILTER]: {ip,arp,ip6}_tables: fix sparse warnings in compat code
CHECK   net/ipv4/netfilter/ip_tables.c
net/ipv4/netfilter/ip_tables.c:1453:8: warning: incorrect type in argument 3 (different signedness)
net/ipv4/netfilter/ip_tables.c:1453:8:    expected int *size
net/ipv4/netfilter/ip_tables.c:1453:8:    got unsigned int [usertype] *size
net/ipv4/netfilter/ip_tables.c:1458:44: warning: incorrect type in argument 3 (different signedness)
net/ipv4/netfilter/ip_tables.c:1458:44:    expected int *size
net/ipv4/netfilter/ip_tables.c:1458:44:    got unsigned int [usertype] *size
net/ipv4/netfilter/ip_tables.c:1603:2: warning: incorrect type in argument 2 (different signedness)
net/ipv4/netfilter/ip_tables.c:1603:2:    expected unsigned int *i
net/ipv4/netfilter/ip_tables.c:1603:2:    got int *<noident>
net/ipv4/netfilter/ip_tables.c:1627:8: warning: incorrect type in argument 3 (different signedness)
net/ipv4/netfilter/ip_tables.c:1627:8:    expected int *size
net/ipv4/netfilter/ip_tables.c:1627:8:    got unsigned int *size
net/ipv4/netfilter/ip_tables.c:1634:40: warning: incorrect type in argument 3 (different signedness)
net/ipv4/netfilter/ip_tables.c:1634:40:    expected int *size
net/ipv4/netfilter/ip_tables.c:1634:40:    got unsigned int *size
net/ipv4/netfilter/ip_tables.c:1653:8: warning: incorrect type in argument 5 (different signedness)
net/ipv4/netfilter/ip_tables.c:1653:8:    expected unsigned int *i
net/ipv4/netfilter/ip_tables.c:1653:8:    got int *<noident>
net/ipv4/netfilter/ip_tables.c:1666:2: warning: incorrect type in argument 2 (different signedness)
net/ipv4/netfilter/ip_tables.c:1666:2:    expected unsigned int *i
net/ipv4/netfilter/ip_tables.c:1666:2:    got int *<noident>
  CHECK   net/ipv4/netfilter/arp_tables.c
net/ipv4/netfilter/arp_tables.c:1285:40: warning: incorrect type in argument 3 (different signedness)
net/ipv4/netfilter/arp_tables.c:1285:40:    expected int *size
net/ipv4/netfilter/arp_tables.c:1285:40:    got unsigned int *size
net/ipv4/netfilter/arp_tables.c:1543:44: warning: incorrect type in argument 3 (different signedness)
net/ipv4/netfilter/arp_tables.c:1543:44:    expected int *size
net/ipv4/netfilter/arp_tables.c:1543:44:    got unsigned int [usertype] *size
  CHECK   net/ipv6/netfilter/ip6_tables.c
net/ipv6/netfilter/ip6_tables.c:1481:8: warning: incorrect type in argument 3 (different signedness)
net/ipv6/netfilter/ip6_tables.c:1481:8:    expected int *size
net/ipv6/netfilter/ip6_tables.c:1481:8:    got unsigned int [usertype] *size
net/ipv6/netfilter/ip6_tables.c:1486:44: warning: incorrect type in argument 3 (different signedness)
net/ipv6/netfilter/ip6_tables.c:1486:44:    expected int *size
net/ipv6/netfilter/ip6_tables.c:1486:44:    got unsigned int [usertype] *size
net/ipv6/netfilter/ip6_tables.c:1631:2: warning: incorrect type in argument 2 (different signedness)
net/ipv6/netfilter/ip6_tables.c:1631:2:    expected unsigned int *i
net/ipv6/netfilter/ip6_tables.c:1631:2:    got int *<noident>
net/ipv6/netfilter/ip6_tables.c:1655:8: warning: incorrect type in argument 3 (different signedness)
net/ipv6/netfilter/ip6_tables.c:1655:8:    expected int *size
net/ipv6/netfilter/ip6_tables.c:1655:8:    got unsigned int *size
net/ipv6/netfilter/ip6_tables.c:1662:40: warning: incorrect type in argument 3 (different signedness)
net/ipv6/netfilter/ip6_tables.c:1662:40:    expected int *size
net/ipv6/netfilter/ip6_tables.c:1662:40:    got unsigned int *size
net/ipv6/netfilter/ip6_tables.c:1680:8: warning: incorrect type in argument 5 (different signedness)
net/ipv6/netfilter/ip6_tables.c:1680:8:    expected unsigned int *i
net/ipv6/netfilter/ip6_tables.c:1680:8:    got int *<noident>
net/ipv6/netfilter/ip6_tables.c:1693:2: warning: incorrect type in argument 2 (different signedness)
net/ipv6/netfilter/ip6_tables.c:1693:2:    expected unsigned int *i
net/ipv6/netfilter/ip6_tables.c:1693:2:    got int *<noident>

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-31 19:27:49 -08:00
Alexey Dobriyan df200969b1 [NETFILTER]: netns: put table module on netns stop
When number of entries exceeds number of initial entries, foo-tables code
will pin table module. But during table unregister on netns stop,
that additional pin was forgotten.

Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-31 19:27:41 -08:00
Alexey Dobriyan 336b517fdc [NETFILTER]: ip6_tables: netns preparation
* Propagate netns from userspace down to xt_find_table_lock()
* Register ip6 tables in netns (modules still use init_net)

Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-31 19:27:39 -08:00
Alexey Dobriyan 44d34e721e [NETFILTER]: x_tables: return new table from {arp,ip,ip6}t_register_table()
Typical table module registers xt_table structure (i.e. packet_filter)
and link it to list during it. We can't use one template for it because
corresponding list_head will become corrupted. We also can't unregister
with template because it wasn't changed at all and thus doesn't know in
which list it is.

So, we duplicate template at the very first step of table registration.
Table modules will save it for use during unregistration time and actual
filtering.

Do it at once to not screw bisection.

P.S.: renaming i.e. packet_filter => __packet_filter is temporary until
      full netnsization of table modules is done.

Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-31 19:27:36 -08:00
Alexey Dobriyan 8d87005207 [NETFILTER]: x_tables: per-netns xt_tables
In fact all we want is per-netns set of rules, however doing that will
unnecessary complicate routines such as ipt_hook()/ipt_do_table, so
make full xt_table array per-netns.

Every user stubbed with init_net for a while.

Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-31 19:27:35 -08:00
Alexey Dobriyan a98da11d88 [NETFILTER]: x_tables: change xt_table_register() return value convention
Switch from 0/-E to ptr/PTR_ERR convention.

Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-31 19:27:35 -08:00
Jan Engelhardt ecb6f85e11 [NETFILTER]: Use const in struct xt_match, xt_target, xt_table
Signed-off-by: Jan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-31 19:27:28 -08:00
Denys Vlasenko 022748a935 [NETFILTER]: {ip,ip6}_tables: remove some inlines
This patch removes inlines except those which are used
by packet matching code and thus are performance-critical.

Before:

$ size */*/*/ip*tables*.o
   text    data     bss     dec     hex filename
   6402     500      16    6918    1b06 net/ipv4/netfilter/ip_tables.o
   7130     500      16    7646    1dde net/ipv6/netfilter/ip6_tables.o

After:

$ size */*/*/ip*tables*.o
   text    data     bss     dec     hex filename
   6307     500      16    6823    1aa7 net/ipv4/netfilter/ip_tables.o
   7010     500      16    7526    1d66 net/ipv6/netfilter/ip6_tables.o

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 15:02:29 -08:00
Jan Engelhardt e79ec50b95 [NETFILTER]: Parenthesize macro parameters
Parenthesize macro parameters.

Signed-off-by: Jan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:59:08 -08:00
Patrick McHardy f01ffbd6e7 [NETFILTER]: nf_log: move logging stuff to seperate header
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:58:58 -08:00
Patrick McHardy da4d0f6b3d [NETFILTER]: ip6_tables: use raw_smp_processor_id() in do_add_counters()
Use raw_smp_processor_id() in do_add_counters() as in ip_tables.c.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:58:41 -08:00
Patrick McHardy b5dd674b2a [NETFILTER]: ip6_tables: fix stack leagage
Fix leakage of local variable on stack. This already got fixed in
ip_tables silently by the compat patches.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:58:40 -08:00
Patrick McHardy c9d8fe1317 [NETFILTER]: {ip,ip6}_tables: fix format strings
Use %zu for sizeof() and remove casts.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:58:39 -08:00
Patrick McHardy 9c54795950 [NETFILTER]: {ip,ip6}_tables: reformat to eliminate differences
Reformat ip_tables.c and ip6_tables.c in order to eliminate non-functional
differences and minimize diff output.

This allows to get a view of the real differences using:

sed -e 's/IP6T/IPT/g' \
    -e 's/IP6/IP/g' \
    -e 's/INET6/INET/g' \
    -e 's/ip6t/ipt/g' \
    -e 's/ip6/ip/g' \
    -e 's/ipv6/ip/g' \
    -e 's/icmp6/icmp/g' \
    net/ipv6/netfilter/ip6_tables.c | \
    diff -wup /dev/stdin net/ipv4/netfilter/ip_tables.c

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:58:39 -08:00
Patrick McHardy 3bc3fe5eed [NETFILTER]: ip6_tables: add compat support
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:58:36 -08:00
Patrick McHardy d924357c50 [NETFILTER]: ip6_tables: resync get_entries() with ip_tables
Resync get_entries() with ip_tables.c by moving the checks from the
setsockopt handler to the function itself.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:58:35 -08:00
Patrick McHardy 433665c9d1 [NETFILTER]: ip6_tables: move IP6T_SO_GET_INFO handling to seperate function
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:58:35 -08:00
Patrick McHardy ed1a6f5e77 [NETFILTER]: ip6_tables: move counter allocation to seperate function
More resyncing with ip_tables.c as preparation for compat support.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:58:34 -08:00
Patrick McHardy 3b84e92b0d [NETFILTER]: ip6_tables: use vmalloc_node()
Consistently use vmalloc_node for all counter allocations.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:58:33 -08:00
Patrick McHardy f173c8a1f2 [NETFILTER]: ip6_tables: move entry, match and target checks to seperate functions
Resync with ip_tables.c as preparation for compat support.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:58:32 -08:00
Patrick McHardy 72f36ec14f [NETFILTER]: ip6_tables: kill a few useless defines/forward declarations
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:58:32 -08:00
Patrick McHardy 9e67d5a739 [NETFILTER]: x_tables: remove obsolete overflow check
We're not multiplying the size with the number of CPUs anymore, so the
check is obsolete.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:55:54 -08:00
Eric Dumazet 259d4e41f3 [NETFILTER]: x_tables: struct xt_table_info diet
Instead of using a big array of NR_CPUS entries, we can compute the size
needed at runtime, using nr_cpu_ids

This should save some ram (especially on David's machines where NR_CPUS=4096 :
32 KB can be saved per table, and 64KB for dynamically allocated ones (because
of slab/slub alignements) )

In particular, the 'bootstrap' tables are not any more static (in data
section) but on stack as their size is now very small.

This also should reduce the size used on stack in compat functions
(get_info() declares an automatic variable, that could be bigger than kernel
stack size for big NR_CPUS)

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:55:54 -08:00
Patrick McHardy 6e23ae2a48 [NETFILTER]: Introduce NF_INET_ hook values
The IPv4 and IPv6 hook values are identical, yet some code tries to figure
out the "correct" value by looking at the address family. Introduce NF_INET_*
values for both IPv4 and IPv6. The old values are kept in a #ifndef __KERNEL__
section for userspace compatibility.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:53:55 -08:00
Herbert Xu 3db05fea51 [NETFILTER]: Replace sk_buff ** with sk_buff *
With all the users of the double pointers removed, this patch mops up by
finally replacing all occurances of sk_buff ** in the netfilter API by
sk_buff *.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-15 12:26:29 -07:00
Neil Horman 16fcec35e7 [NETFILTER]: Fix/improve deadlock condition on module removal netfilter
So I've had a deadlock reported to me.  I've found that the sequence of
events goes like this:

1) process A (modprobe) runs to remove ip_tables.ko

2) process B (iptables-restore) runs and calls setsockopt on a netfilter socket,
increasing the ip_tables socket_ops use count

3) process A acquires a file lock on the file ip_tables.ko, calls remove_module
in the kernel, which in turn executes the ip_tables module cleanup routine,
which calls nf_unregister_sockopt

4) nf_unregister_sockopt, seeing that the use count is non-zero, puts the
calling process into uninterruptible sleep, expecting the process using the
socket option code to wake it up when it exits the kernel

4) the user of the socket option code (process B) in do_ipt_get_ctl, calls
ipt_find_table_lock, which in this case calls request_module to load
ip_tables_nat.ko

5) request_module forks a copy of modprobe (process C) to load the module and
blocks until modprobe exits.

6) Process C. forked by request_module process the dependencies of
ip_tables_nat.ko, of which ip_tables.ko is one.

7) Process C attempts to lock the request module and all its dependencies, it
blocks when it attempts to lock ip_tables.ko (which was previously locked in
step 3)

Theres not really any great permanent solution to this that I can see, but I've
developed a two part solution that corrects the problem

Part 1) Modifies the nf_sockopt registration code so that, instead of using a
use counter internal to the nf_sockopt_ops structure, we instead use a pointer
to the registering modules owner to do module reference counting when nf_sockopt
calls a modules set/get routine.  This prevents the deadlock by preventing set 4
from happening.

Part 2) Enhances the modprobe utilty so that by default it preforms non-blocking
remove operations (the same way rmmod does), and add an option to explicity
request blocking operation.  So if you select blocking operation in modprobe you
can still cause the above deadlock, but only if you explicity try (and since
root can do any old stupid thing it would like....  :)  ).

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-11 11:28:26 +02:00
Patrick McHardy a887c1c148 [NETFILTER]: Lower *tables printk severity
Lower ip6tables, arptables and ebtables printk severity similar to
Dan Aloni's patch for iptables.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-14 20:46:15 -07:00
Patrick McHardy 9f15c5302d [NETFILTER]: x_tables: mark matches and targets __read_mostly
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:17:15 -07:00
Jozsef Kadlecsik ba9dda3ab5 [NETFILTER]: x_tables: add TRACE target
The TRACE target can be used to follow IP and IPv6 packets through
the ruleset.

Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Patrick NcHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:17:14 -07:00
Jan Engelhardt ccb79bdce7 [NETFILTER]: x_tables: switch xt_match->checkentry to bool
Switch the return type of match functions to boolean

Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:16:58 -07:00
Jan Engelhardt 1d93a9cbad [NETFILTER]: x_tables: switch xt_match->match to bool
Switch the return type of match functions to boolean

Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:16:57 -07:00
Jan Engelhardt cff533ac12 [NETFILTER]: x_tables: switch hotdrop to bool
Switch the "hotdrop" variables to boolean

Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:16:56 -07:00