We currently use a percpu spinlock to 'protect' rule bytes/packets
counters, after various attempts to use RCU instead.
Lately we added a seqlock so that get_counters() can run without
blocking BH or 'writers'. But we really only need the seqcount in it.
Spinlock itself is only locked by the current/owner cpu, so we can
remove it completely.
This cleanups api, using correct 'writer' vs 'reader' semantic.
At replace time, the get_counters() call makes sure all cpus are done
using the old table.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
commit f3c5c1bfd4 (make ip_tables reentrant) introduced a race in
handling the stackptr restore, at the end of ipt_do_table()
We should do it before the call to xt_info_rdunlock_bh(), or we allow
cpu preemption and another cpu overwrites stackptr of original one.
A second fix is to change the underflow test to check the origptr value
instead of 0 to detect underflow, or else we allow a jump from different
hooks.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Structures ip6t_replace, compat_ip6t_replace, and xt_get_revision are
copied from userspace. Fields of these structs that are
zero-terminated strings are not checked. When they are used as argument
to a format string containing "%s" in request_module(), some sensitive
information is leaked to userspace via argument of spawned modprobe
process.
The first bug was introduced before the git epoch; the second was
introduced in 3bc3fe5e (v2.6.25-rc1); the third is introduced by
6b7d31fc (v2.6.15-rc1). To trigger the bug one should have
CAP_NET_ADMIN.
Signed-off-by: Vasiliy Kulikov <segoon@openwall.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
One iptables invocation with 135000 rules takes 35 seconds of cpu time
on a recent server, using a 32bit distro and a 64bit kernel.
We eventually trigger NMI/RCU watchdog.
INFO: rcu_sched_state detected stall on CPU 3 (t=6000 jiffies)
COMPAT mode has quadratic behavior and consume 16 bytes of memory per
rule.
Switch the xt_compat algos to use an array instead of list, and use a
binary search to locate an offset in the sorted array.
This halves memory need (8 bytes per rule), and removes quadratic
behavior [ O(N*N) -> O(N*log2(N)) ]
Time of iptables goes from 35 s to 150 ms.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Using "iptables -L" with a lot of rules have a too big BH latency.
Jesper mentioned ~6 ms and worried of frame drops.
Switch to a per_cpu seqlock scheme, so that taking a snapshot of
counters doesnt need to block BH (for this cpu, but also other cpus).
This adds two increments on seqlock sequence per ipt_do_table() call,
its a reasonable cost for allowing "iptables -L" not block BH
processing.
Reported-by: Jesper Dangaard Brouer <hawk@comx.dk>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Patrick McHardy <kaber@trash.net>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Acked-by: Jesper Dangaard Brouer <hawk@comx.dk>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Many of the used macros are just there for userspace compatibility.
Substitute the in-kernel code to directly use the terminal macro
and stuff the defines into #ifndef __KERNEL__ sections.
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Change "return (EXPR);" to "return EXPR;"
return is not a function, parentheses are not required.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
commit f3c5c1bfd4
(netfilter: xtables: make ip_tables reentrant) forgot to
also compute the jumpstack size in the compat handlers.
Result is that "iptables -I INPUT -j userchain" turns into -j DROP.
Reported by Sebastian Roesner on #netfilter, closes
http://bugzilla.netfilter.org/show_bug.cgi?id=669.
Note: arptables change is compile-tested only.
Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Tested-by: Mikael Pettersson <mikpe@it.uu.se>
Signed-off-by: David S. Miller <davem@davemloft.net>
After commit 24b36f019 (netfilter: {ip,ip6,arp}_tables: dont block
bottom half more than necessary), lockdep can raise a warning
because we attempt to lock a spinlock with BH enabled, while
the same lock is usually locked by another cpu in a softirq context.
Disable again BH to avoid these lockdep warnings.
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Diagnosed-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We currently disable BH for the whole duration of get_counters()
On machines with a lot of cpus and large tables, this might be too long.
We can disable preemption during the whole function, and disable BH only
while fetching counters for the current cpu.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
ipv6_hdr(skb)->payload_len is ZERO and can't be used for accounting, if
the payload is a Jumbo Payload specified in RFC2675.
Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Using vmalloc_node(size, numa_node_id()) for temporary storage is not
needed. vmalloc(size) is more respectful of user NUMA policy.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
commit f3c5c1bfd4 (netfilter: xtables: make ip_tables reentrant)
introduced a performance regression, because stackptr array is shared by
all cpus, adding cache line ping pongs. (16 cpus share a 64 bytes cache
line)
Fix this using alloc_percpu()
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-By: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Make sure all printk messages have a severity level.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Change netfilter asserts to standard WARN_ON. This has the
benefit of backtrace info and also causes netfilter errors
to show up on kerneloops.org.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Prepare the arrays for use with the multiregister function. The
future layer-3 xt matches can then be easily added to it without
needing more (un)register code.
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Since xt_action_param is writable, let's use it. The pointer to
'bool hotdrop' always worried (8 bytes (64-bit) to write 1 byte!).
Surprisingly results in a reduction in size:
text data bss filename
5457066 692730 357892 vmlinux.o-prev
5456554 692730 357892 vmlinux.o
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
In future, layer-3 matches will be an xt module of their own, and
need to set the fragoff and thoff fields. Adding more pointers would
needlessy increase memory requirements (esp. so for 64-bit, where
pointers are wider).
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
The structures carried - besides match/target - almost the same data.
It is possible to combine them, as extensions are evaluated serially,
and so, the callers end up a little smaller.
text data bss filename
-15318 740 104 net/ipv4/netfilter/ip_tables.o
+15286 740 104 net/ipv4/netfilter/ip_tables.o
-15333 540 152 net/ipv6/netfilter/ip6_tables.o
+15269 540 152 net/ipv6/netfilter/ip6_tables.o
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Currently, the table traverser stores return addresses in the ruleset
itself (struct ip6t_entry->comefrom). This has a well-known drawback:
the jumpstack is overwritten on reentry, making it necessary for
targets to return absolute verdicts. Also, the ruleset (which might
be heavy memory-wise) needs to be replicated for each CPU that can
possibly invoke ip6t_do_table.
This patch decouples the jumpstack from struct ip6t_entry and instead
puts it into xt_table_info. Not being restricted by 'comefrom'
anymore, we can set up a stack as needed. By default, there is room
allocated for two entries into the traverser.
arp_tables is not touched though, because there is just one/two
modules and further patches seek to collapse the table traverser
anyhow.
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Restore function signatures from bool to int so that we can report
memory allocation failures or similar using -ENOMEM rather than
always having to pass -EINVAL back.
This semantic patch may not be too precise (checking for functions
that use xt_mtchk_param rather than functions referenced by
xt_match.checkentry), but reviewed, it produced the intended result.
// <smpl>
@@
type bool;
identifier check, par;
@@
-bool check
+int check
(struct xt_mtchk_param *par) { ... }
// </smpl>
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Supplement to 1159683ef4.
Downgrade the log level to INFO for most checkentry messages as they
are, IMO, just an extra information to the -EINVAL code that is
returned as part of a parameter "constraint violation". Leave errors
to real errors, such as being unable to create a LED trigger.
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Just pass in the entire repl struct. In case of a new table (e.g.
ip6t_register_table), the repldata has been previously filled with
table->name and table->size already (in ip6t_alloc_initial_table).
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
The macro is replaced by a list.h-like foreach loop. This makes
the code more inspectable.
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
The macro is replaced by a list.h-like foreach loop. This makes
the code much more inspectable.
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
The static initial tables are pretty large, and after the net
namespace has been instantiated, they just hang around for nothing.
This commit removes them and creates tables on-demand at runtime when
needed.
Size shrinks by 7735 bytes (x86_64).
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
As per C99 6.2.4(2) when temporary table data goes out of scope,
the behaviour is undefined:
if (compat) {
struct foo tmp;
...
private = &tmp;
}
[dereference private]
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: stable@kernel.org
Signed-off-by: Patrick McHardy <kaber@trash.net>
Add ->net to match destructor list like ->net in constructor list.
Make sure it's set in ebtables/iptables/ip6tables, this requires to
propagate netns up to *_unregister_table().
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Some complex match modules (like xt_hashlimit/xt_recent) want netns
information at constructor and destructor time. We propably can play
games at match destruction time, because netns can be passed in object,
but I think it's cleaner to explicitly pass netns.
Add ->net, make sure it's set from ebtables/iptables/ip6tables code.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
The inputted table is never modified, so should be considered const.
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
This adds the second check that Rusty wanted to have a long time ago. :-)
Base chain policies must have absolute verdicts that cease processing
in the table, otherwise rule execution may continue in an unexpected
spurious fashion (e.g. next chain that follows in memory).
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
This adds a check that iptables's original author Rusty set forth in
a FIXME comment.
Underflows in iptables are better known as chain policies, and are
required to be unconditional or there would be a stochastical chance
for the policy rule to be skipped if it does not match. If that were
to happen, rule execution would continue in an unexpected spurious
fashion.
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
The "hook_entry" and "underflow" array contains values even for hooks
not provided, such as PREROUTING in conjunction with the "filter"
table. Usually, the values point to whatever the next rule is. For
the upcoming unconditionality and underflow checking patches however,
we must not inspect that arbitrary rule.
Skipping unassigned hooks seems like a good idea, also because
newinfo->hook_entry and newinfo->underflow will then continue to have
the poison value for detecting abnormalities.
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Instead of inspecting each u32/char open-coded, clean up and make use
of memcmp. On some arches, memcmp is implemented as assembly or GCC's
__builtin_memcmp which can possibly take advantages of known
alignment.
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
The x_tables are organized with a table structure and a per-cpu copies
of the counters and rules. On older kernels there was a reader/writer
lock per table which was a performance bottleneck. In 2.6.30-rc, this
was converted to use RCU and the counters/rules which solved the performance
problems for do_table but made replacing rules much slower because of
the necessary RCU grace period.
This version uses a per-cpu set of spinlocks and counters to allow to
table processing to proceed without the cache thrashing of a global
reader lock and keeps the same performance for table updates.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
__FUNCTION__ is gcc-specific, use __func__
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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>
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>
* 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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
Now the skb->nh union has just one member, .raw, i.e. it is just like the
skb->mac union, strange, no? I'm just leaving it like that till the transport
layer is done with, when we'll rename skb->mac.raw to skb->mac_header (or
->mac_header_offset?), ditto for ->{h,nh}.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use the x_tables functions directly to make it better visible which
parts are shared between ip_tables and ip6_tables.
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>
If we come to node we'd already marked as seen and it's not a part of path
(i.e. we don't have a loop right there), we already know that it isn't a
part of any loop, so we don't need to revisit it.
That speeds the things up if some chain is refered to from several places
and kills O(exp(table size)) worst-case behaviour (without sleeping,
at that, so if you manage to self-LART that way, you are SOL for a long
time)...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 590bdf7fd2 introduced a regression
in match/target hook validation. mark_source_chains builds a bitmask
for each rule representing the hooks it can be reached from, which is
then used by the matches and targets to make sure they are only called
from valid hooks. The patch moved the match/target specific validation
before the mark_source_chains call, at which point the mask is always zero.
This patch returns back to the old order and moves the standard checks
to mark_source_chains. This allows to get rid of a special case for
standard targets as a nice side-effect.
Signed-off-by: Dmitry Mishin <dim@openvz.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
nexthdr is NEXTHDR_FRAGMENT, the nexthdr value from the fragment header
is hp->nexthdr.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
There is a number of issues in parsing user-provided table in
translate_table(). Malicious user with CAP_NET_ADMIN may crash system by
passing special-crafted table to the *_tables.
The first issue is that mark_source_chains() function is called before entry
content checks. In case of standard target, mark_source_chains() function
uses t->verdict field in order to determine new position. But the check, that
this field leads no further, than the table end, is in check_entry(), which
is called later, than mark_source_chains().
The second issue, that there is no check that target_offset points inside
entry. If so, *_ITERATE_MATCH macro will follow further, than the entry
ends. As a result, we'll have oops or memory disclosure.
And the third issue, that there is no check that the target is completely
inside entry. Results are the same, as in previous issue.
Signed-off-by: Dmitry Mishin <dim@openvz.org>
Acked-by: Kirill Korotaev <dev@openvz.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
As reported by Mark Dowd <Mark_Dowd@McAfee.com>, ip6_tables is susceptible
to a fragmentation attack causing false negatives on extension header matches.
When extension headers occur in the non-first fragment after the fragment
header (possibly with an incorrect nexthdr value in the fragment header)
a rule looking for this extension header will never match.
Drop fragments that are at offset 0 and don't contain the final protocol
header regardless of the ruleset, since this should not happen normally.
Since all extension headers are before the protocol header this makes sure
an extension header is either not present or in the first fragment, where
we can properly parse it.
With help from Yasuyuki KOZAKAI <yasuyuki.kozakai@toshiba.co.jp>.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
As reported by Mark Dowd <Mark_Dowd@McAfee.com>, ip6_tables is susceptible
to a fragmentation attack causing false negatives on protocol matches.
When the protocol header doesn't follow the fragment header immediately,
the fragment header contains the protocol number of the next extension
header. When the extension header and the protocol header are sent in
a second fragment a rule like "ip6tables .. -p udp -j DROP" will never
match.
Drop fragments that are at offset 0 and don't contain the final protocol
header regardless of the ruleset, since this should not happen normally.
With help from Yasuyuki KOZAKAI <yasuyuki.kozakai@toshiba.co.jp>.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
While standard_target has target->me == NULL, module_put() should be
called for it as for others, because there were try_module_get() before.
Signed-off-by: Dmitry Mishin <dim@openvz.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Kill listhelp.h and use the list.h functions instead.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
The size is verified by x_tables and isn't needed by the modules anymore.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Neither of {arp,ip,ip6}_tables cleans up behind itself when something goes
wrong during initialization.
Noticed by Rennie deGraaf <degraaf@cpsc.ucalgary.ca>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
When xt_register_table fails the error is not properly propagated back.
Based on patch by Lepton Wu <ytht.net@gmail.com>.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Solar Designer found a race condition in do_add_counters(). The beginning
of paddc is supposed to be the same as tmp which was sanity-checked
above, but it might not be the same in reality. In case the integer
overflow and/or the race condition are triggered, paddc->num_counters
might not match the allocation size for paddc. If the check below
(t->private->number != paddc->num_counters) nevertheless passes (perhaps
this requires the race condition to be triggered), IPT_ENTRY_ITERATE()
would read kernel memory beyond the allocation size, potentially causing
an oops or leaking sensitive data (e.g., passwords from host system or
from another VPS) via counter increments. This requires CAP_NET_ADMIN.
Signed-off-by: Solar Designer <solar@openwall.com>
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>
The introduction of x_tables broke comefrom debugging, remove it from
ip6_tables as well (ip_tables already got removed).
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
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>
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>
Set the family field in xt_[matches|targets] registered.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.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: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Replace netfilter's ip6_masked_addrcmp by a more efficient version
in include/net/ipv6.h to make it usable without module dependencies.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This allows to make decisions based on the revision (and address family
with a follow-up patch) at runtime.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
netfilter's do_replace() can overflow on addition within SMP_ALIGN()
and/or on multiplication by NR_CPUS, resulting in a buffer overflow on
the copy_from_user(). In practice, the overflow on addition is
triggerable on all systems, whereas the multiplication one might require
much physical memory to be present due to the check above. Either is
sufficient to overwrite arbitrary amounts of kernel memory.
I really hate adding the same check to all 4 versions of do_replace(),
but the code is duplicate...
Found by Solar Designer during security audit of OpenVZ.org
Signed-Off-By: Kirill Korotaev <dev@openvz.org>
Signed-Off-By: Solar Designer <solar@openwall.com>
Signed-off-by: Patrck McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller