commit 2f941622fd upstream.
WARNING: CPU: 1 PID: 16059 at lib/refcount.c:31 refcount_warn_saturate+0xdf/0xf
[..]
__nft_mt_tg_destroy+0x42/0x50 [nft_compat]
nft_target_destroy+0x63/0x80 [nft_compat]
nf_tables_expr_destroy+0x1b/0x30 [nf_tables]
nf_tables_rule_destroy+0x3a/0x70 [nf_tables]
nf_tables_exit_net+0x186/0x3d0 [nf_tables]
Happens when a compat expr is destoyed from abort path.
There is no functional impact; after this work queue is flushed
unconditionally if its pending.
This removes the waitcount optimization. Test of repeated
iptables-restore of a ~60k kubernetes ruleset doesn't indicate
a slowdown. In case the counter is needed after all for some workloads
we can revert this and increment the refcount for the
!= NFT_PREPARE_TRANS case to avoid the increment/decrement imbalance.
While at it, also flush for match case, this was an oversight
in the original patch.
Fixes: ffe8923f10 ("netfilter: nft_compat: make sure xtables destructors have run")
Reported-by: kernel test robot <rong.a.chen@intel.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit ffe8923f10 ]
Pablo Neira found that after recent update of xt_IDLETIMER the
iptables-nft tests sometimes show an error.
He tracked this down to the delayed cleanup used by nf_tables core:
del rule (transaction A)
add rule (transaction B)
Its possible that by time transaction B (both in same netns) runs,
the xt target destructor has not been invoked yet.
For native nft expressions this is no problem because all expressions
that have such side effects make sure these are handled from the commit
phase, rather than async cleanup.
For nft_compat however this isn't true.
Instead of forcing synchronous behaviour for nft_compat, keep track
of the number of outstanding destructor calls.
When we attempt to create a new expression, flush the cleanup worker
to make sure destructors have completed.
With lots of help from Pablo Neira.
Reported-by: Pablo Neira Ayso <pablo@netfilter.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Based on 2 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation #
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 4122 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We currently have two levels of strict validation:
1) liberal (default)
- undefined (type >= max) & NLA_UNSPEC attributes accepted
- attribute length >= expected accepted
- garbage at end of message accepted
2) strict (opt-in)
- NLA_UNSPEC attributes accepted
- attribute length >= expected accepted
Split out parsing strictness into four different options:
* TRAILING - check that there's no trailing data after parsing
attributes (in message or nested)
* MAXTYPE - reject attrs > max known type
* UNSPEC - reject attributes with NLA_UNSPEC policy entries
* STRICT_ATTRS - strictly validate attribute size
The default for future things should be *everything*.
The current *_strict() is a combination of TRAILING and MAXTYPE,
and is renamed to _deprecated_strict().
The current regular parsing has none of this, and is renamed to
*_parse_deprecated().
Additionally it allows us to selectively set one of the new flags
even on old policies. Notably, the UNSPEC flag could be useful in
this case, since it can be arranged (by filling in the policy) to
not be an incompatible userspace ABI change, but would then going
forward prevent forgetting attribute entries. Similar can apply
to the POLICY flag.
We end up with the following renames:
* nla_parse -> nla_parse_deprecated
* nla_parse_strict -> nla_parse_deprecated_strict
* nlmsg_parse -> nlmsg_parse_deprecated
* nlmsg_parse_strict -> nlmsg_parse_deprecated_strict
* nla_parse_nested -> nla_parse_nested_deprecated
* nla_validate_nested -> nla_validate_nested_deprecated
Using spatch, of course:
@@
expression TB, MAX, HEAD, LEN, POL, EXT;
@@
-nla_parse(TB, MAX, HEAD, LEN, POL, EXT)
+nla_parse_deprecated(TB, MAX, HEAD, LEN, POL, EXT)
@@
expression NLH, HDRLEN, TB, MAX, POL, EXT;
@@
-nlmsg_parse(NLH, HDRLEN, TB, MAX, POL, EXT)
+nlmsg_parse_deprecated(NLH, HDRLEN, TB, MAX, POL, EXT)
@@
expression NLH, HDRLEN, TB, MAX, POL, EXT;
@@
-nlmsg_parse_strict(NLH, HDRLEN, TB, MAX, POL, EXT)
+nlmsg_parse_deprecated_strict(NLH, HDRLEN, TB, MAX, POL, EXT)
@@
expression TB, MAX, NLA, POL, EXT;
@@
-nla_parse_nested(TB, MAX, NLA, POL, EXT)
+nla_parse_nested_deprecated(TB, MAX, NLA, POL, EXT)
@@
expression START, MAX, POL, EXT;
@@
-nla_validate_nested(START, MAX, POL, EXT)
+nla_validate_nested_deprecated(START, MAX, POL, EXT)
@@
expression NLH, HDRLEN, MAX, POL, EXT;
@@
-nlmsg_validate(NLH, HDRLEN, MAX, POL, EXT)
+nlmsg_validate_deprecated(NLH, HDRLEN, MAX, POL, EXT)
For this patch, don't actually add the strict, non-renamed versions
yet so that it breaks compile if I get it wrong.
Also, while at it, make nla_validate and nla_parse go down to a
common __nla_validate_parse() function to avoid code duplication.
Ultimately, this allows us to have very strict validation for every
new caller of nla_parse()/nlmsg_parse() etc as re-introduced in the
next patch, while existing things will continue to work as is.
In effect then, this adds fully strict validation for any new command.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add .release_ops, that is called in case of error at a later stage in
the expression initialization path, ie. .select_ops() has been already
set up operations and that needs to be undone. This allows us to unwind
.select_ops from the error path, ie. release the dynamic operations for
this extension.
Moreover, allocate one single operation instead of recycling them, this
comes at the cost of consuming a bit more memory per rule, but it
simplifies the infrastructure.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
When I moved the refcount to refcount_t type I missed the fact that
refcount_inc() will result in use-after-free warning with
CONFIG_REFCOUNT_FULL=y builds.
The correct fix would be to init the reference count to 1 at allocation
time, but, unfortunately we cannot do this, as we can't undo that
in case something else fails later in the batch.
So only solution I see is to special-case the 'new entry' condition
and replace refcount_inc() with a "delayed" refcount_set(1) in this case,
as done here.
The .activate callback can be removed to simplify things, we only
need to make sure that deactivate() decrements/unlinks the entry
from the list at end of transaction phase (commit or abort).
Fixes: 12c44aba66 ("netfilter: nft_compat: use refcnt_t type for nft_xt reference count")
Reported-by: Jordan Glover <Golden_Miller83@protonmail.ch>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Anonymous sets that are bound to rules from the same transaction trigger
a kernel splat from the abort path due to double set list removal and
double free.
This patch updates the logic to search for the transaction that is
responsible for creating the set and disable the set list removal and
release, given the rule is now responsible for this. Lookup is reverse
since the transaction that adds the set is likely to be at the tail of
the list.
Moreover, this patch adds the unbind step to deliver the event from the
commit path. This should not be done from the worker thread, since we
have no guarantees of in-order delivery to the listener.
This patch removes the assumption that both activate and deactivate
callbacks need to be provided.
Fixes: cd5125d8f5 ("netfilter: nf_tables: split set destruction in deactivate and destroy phase")
Reported-by: Mikhail Morfikov <mmorfikov@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The nft_compat destroy function deletes the nft_xt object from a list.
This isn't allowed anymore. Destroy functions are called asynchronously,
i.e. next batch can find the object that has a pending ->destroy()
invocation:
cpu0 cpu1
worker
->destroy for_each_entry()
if (x == ...
return x->ops;
list_del(x)
kfree_rcu(x)
expr->ops->... // ops was free'd
To resolve this, the list_del needs to occur before the transaction
mutex gets released. nf_tables has a 'deactivate' hook for this
purpose, so use that to unlink the object from the list.
Fixes: 0935d55884 ("netfilter: nf_tables: asynchronous release")
Reported-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
There are two problems with nft_compat since the netlink config
plane uses a per-netns mutex:
1. Concurrent add/del accesses to the same list
2. accesses to a list element after it has been free'd already.
This patch fixes the first problem.
Freeing occurs from a work queue, after transaction mutexes have been
released, i.e., it still possible for a new transaction (even from
same net ns) to find the to-be-deleted expression in the list.
The ->destroy functions are not allowed to have any such side effects,
i.e. the list_del() in the destroy function is not allowed.
This part of the problem is solved in the next patch.
I tried to make this work by serializing list access via mutex
and by moving list_del() to a deactivate callback, but
Taehee spotted following race on this approach:
NET #0 NET #1
>select_ops()
->init()
->select_ops()
->deactivate()
->destroy()
nft_xt_put()
kfree_rcu(xt, rcu_head);
->init() <-- use-after-free occurred.
Unfortunately, we can't increment reference count in
select_ops(), because we can't undo the refcount increase in
case a different expression fails in the same batch.
(The destroy hook will only be called in case the expression
was initialized successfully).
Fixes: f102d66b33 ("netfilter: nf_tables: use dedicated mutex to guard transactions")
Reported-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Using standard integer type was fine while all operations on it were
guarded by the nftnl subsys mutex.
This isn't true anymore:
1. transactions are guarded only by a pernet mutex, so concurrent
rule manipulation in different netns is racy
2. the ->destroy hook runs from a work queue after the transaction
mutex has been released already.
cpu0 cpu1 (net 1) cpu2 (net 2)
kworker
nft_compat->destroy nft_compat->init nft_compat->init
if (--nft_xt->ref == 0) nft_xt->ref++ nft_xt->ref++
Switch to refcount_t. Doing this however only fixes a minor aspect,
nft_compat also performs linked-list operations in an unsafe way.
This is addressed in the next two patches.
Fixes: f102d66b33 ("netfilter: nf_tables: use dedicated mutex to guard transactions")
Fixes: 0935d55884 ("netfilter: nf_tables: asynchronous release")
Reported-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
nft_compat ops do not have static storage duration, unlike all other
expressions.
When nf_tables_expr_destroy() returns, expr->ops might have been
free'd already, so we need to store next address before calling
expression destructor.
For same reason, we can't deref match pointer after nft_xt_put().
This can be easily reproduced by adding msleep() before
nft_match_destroy() returns.
Fixes: 0ca743a559 ("netfilter: nf_tables: add compatibility layer for x_tables")
Reported-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Unlike ip(6)tables, the ebtables nat table has no special properties.
This bug causes 'ebtables -A' to fail when using a target such as
'snat' (ebt_snat target sets ".table = "nat"'). Targets that have
no table restrictions work fine.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Zero pad private area, otherwise we expose private kernel pointer to
userspace. This patch also zeroes the tail area after the ->matchsize
and ->targetsize that results from XT_ALIGN().
Fixes: 0ca743a559 ("netfilter: nf_tables: add compatibility layer for x_tables")
Reported-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
iptables-nft never requests these, but make this explicitly illegal.
If it were quested, kernel could oops as ->eval is NULL, furthermore,
the builtin targets have no owning module so its possible to rmmod
eb/ip/ip6_tables module even if they would be loaded.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Just use .call_rcu instead. We can drop the rcu read lock
after obtaining a reference and re-acquire on return.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
currently matchinfo gets stored in the expression, but some xt matches
are very large.
To handle those we either need to switch nft core to kvmalloc and increase
size limit, or allocate the info blob of large matches separately.
This does the latter, this limits the scope of the changes to
nft_compat.
I picked a threshold of 192, this allows most matches to work as before and
handle only few ones via separate alloation (cgroup, u32, sctp, rt).
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Next patch will make it possible for *info to be stored in
a separate allocation instead of the expr private area.
This removes the 'expr priv area is info blob' assumption
from the match init/destroy/eval functions.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Taehee Yoo reported following bug:
iptables-compat -I OUTPUT -m cpu --cpu 0
iptables-compat -F
lsmod |grep xt_cpu
xt_cpu 16384 1
Quote:
"When above command is given, a netlink message has two expressions that
are the cpu compat and the nft_counter.
The nft_expr_type_get() in the nf_tables_expr_parse() successes
first expression then, calls select_ops callback.
(allocates memory and holds module)
But, second nft_expr_type_get() in the nf_tables_expr_parse()
returns -EAGAIN because of request_module().
In that point, by the 'goto err1',
the 'module_put(info[i].ops->type->owner)' is called.
There is no release routine."
The core problem is that unlike all other expression,
nft_compat select_ops has side effects.
1. it allocates dynamic memory which holds an nft ops struct.
In all other expressions, ops has static storage duration.
2. It grabs references to the xt module that it is supposed to
invoke.
Depending on where things go wrong, error unwinding doesn't
always do the right thing.
In the above scenario, a new nft_compat_expr is created and
xt_cpu module gets loaded with a refcount of 1.
Due to to -EAGAIN, the netlink messages get re-parsed.
When that happens, nft_compat finds that xt_cpu is already present
and increments module refcount again.
This fixes the problem by making select_ops to have no visible
side effects and removes all extra module_get/put.
When select_ops creates a new nft_compat expression, the new
expression has a refcount of 0, and the xt module gets its refcount
incremented.
When error happens, the next call finds existing entry, but will no
longer increase the reference count -- the presence of existing
nft_xt means we already hold a module reference.
Because nft_xt_put is only called from nft_compat destroy hook,
it will never see the initial zero reference count.
->destroy can only be called after ->init(), and that will increase the
refcount.
Lastly, we now free nft_xt struct with kfree_rcu.
Else, we get use-after free in nf_tables_rule_destroy:
while (expr != nft_expr_last(rule) && expr->ops) {
nf_tables_expr_destroy(ctx, expr);
expr = nft_expr_next(expr); // here
nft_expr_next() dereferences expr->ops. This is safe
for all users, as ops have static storage duration.
In nft_compat case however, its ->destroy callback can
free the memory that hold the ops structure.
Tested-by: Taehee Yoo <ap420073@gmail.com>
Reported-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Several reasons for this:
* Several modules maintain internal version numbers, that they print at
boot/module load time, that are not exposed to userspace, as a
primitive mechanism to make revision number control from the earlier
days of Netfilter.
* IPset shows the protocol version at boot/module load time, instead
display this via module description, as Jozsef suggested.
* Remove copyright notice at boot/module load time in two spots, the
Netfilter codebase is a collective development effort, if we would
have to display copyrights for each contributor at boot/module load
time for each extensions we have, we would probably fill up logs with
lots of useless information - from a technical standpoint.
So let's be consistent and remove them all.
Acked-by: Florian Westphal <fw@strlen.de>
Acked-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Place all existing user defined tables in struct net *, instead of
having one list per family. This saves us from one level of indentation
in netlink dump functions.
Place pointer to struct nft_af_info in struct nft_table temporarily, as
we still need this to put back reference module reference counter on
table removal.
This patch comes in preparation for the removal of struct nft_af_info.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Since NFPROTO_INET is handled from the core, we don't need to maintain
extra infrastructure in nf_tables to handle the double hook
registration, one for IPv4 and another for IPv6.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Pass down struct netlink_ext_ack as parameter to all of our nfnetlink
subsystem callbacks, so we can work on follow up patches to provide
finer grain error reporting using the new infrastructure that
2d4bc93368 ("netlink: extended ACK reporting") provides.
No functional change, just pass down this new object to callbacks.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Pablo Neira Ayuso says:
====================
Netfilter/IPVS updates for net-next
The following patchset contains Netfilter updates for your net-next
tree. A large bunch of code cleanups, simplify the conntrack extension
codebase, get rid of the fake conntrack object, speed up netns by
selective synchronize_net() calls. More specifically, they are:
1) Check for ct->status bit instead of using nfct_nat() from IPVS and
Netfilter codebase, patch from Florian Westphal.
2) Use kcalloc() wherever possible in the IPVS code, from Varsha Rao.
3) Simplify FTP IPVS helper module registration path, from Arushi Singhal.
4) Introduce nft_is_base_chain() helper function.
5) Enforce expectation limit from userspace conntrack helper,
from Gao Feng.
6) Add nf_ct_remove_expect() helper function, from Gao Feng.
7) NAT mangle helper function return boolean, from Gao Feng.
8) ctnetlink_alloc_expect() should only work for conntrack with
helpers, from Gao Feng.
9) Add nfnl_msg_type() helper function to nfnetlink to build the
netlink message type.
10) Get rid of unnecessary cast on void, from simran singhal.
11) Use seq_puts()/seq_putc() instead of seq_printf() where possible,
also from simran singhal.
12) Use list_prev_entry() from nf_tables, from simran signhal.
13) Remove unnecessary & on pointer function in the Netfilter and IPVS
code.
14) Remove obsolete comment on set of rules per CPU in ip6_tables,
no longer true. From Arushi Singhal.
15) Remove duplicated nf_conntrack_l4proto_udplite4, from Gao Feng.
16) Remove unnecessary nested rcu_read_lock() in
__nf_nat_decode_session(). Code running from hooks are already
guaranteed to run under RCU read side.
17) Remove deadcode in nf_tables_getobj(), from Aaron Conole.
18) Remove double assignment in nf_ct_l4proto_pernet_unregister_one(),
also from Aaron.
19) Get rid of unsed __ip_set_get_netlink(), from Aaron Conole.
20) Don't propagate NF_DROP error to userspace via ctnetlink in
__nf_nat_alloc_null_binding() function, from Gao Feng.
21) Revisit nf_ct_deliver_cached_events() to remove unnecessary checks,
from Gao Feng.
22) Kill the fake untracked conntrack objects, use ctinfo instead to
annotate a conntrack object is untracked, from Florian Westphal.
23) Remove nf_ct_is_untracked(), now obsolete since we have no
conntrack template anymore, from Florian.
24) Add event mask support to nft_ct, also from Florian.
25) Move nf_conn_help structure to
include/net/netfilter/nf_conntrack_helper.h.
26) Add a fixed 32 bytes scratchpad area for conntrack helpers.
Thus, we don't deal with variable conntrack extensions anymore.
Make sure userspace conntrack helper doesn't go over that size.
Remove variable size ct extension infrastructure now this code
got no more clients. From Florian Westphal.
27) Restore offset and length of nf_ct_ext structure to 8 bytes now
that wraparound is not possible any longer, also from Florian.
28) Allow to get rid of unassured flows under stress in conntrack,
this applies to DCCP, SCTP and TCP protocols, from Florian.
29) Shrink size of nf_conntrack_ecache structure, from Florian.
30) Use TCP_MAX_WSCALE instead of hardcoded 14 in TCP tracker,
from Gao Feng.
31) Register SYNPROXY hooks on demand, from Florian Westphal.
32) Use pernet hook whenever possible, instead of global hook
registration, from Florian Westphal.
33) Pass hook structure to ebt_register_table() to consolidate some
infrastructure code, from Florian Westphal.
34) Use consume_skb() and return NF_STOLEN, instead of NF_DROP in the
SYNPROXY code, to make sure device stats are not fooled, patch
from Gao Feng.
35) Remove NF_CT_EXT_F_PREALLOC this kills quite some code that we
don't need anymore if we just select a fixed size instead of
expensive runtime time calculation of this. From Florian.
36) Constify nf_ct_extend_register() and nf_ct_extend_unregister(),
from Florian.
37) Simplify nf_ct_ext_add(), this kills nf_ct_ext_create(), from
Florian.
38) Attach NAT extension on-demand from masquerade and pptp helper
path, from Florian.
39) Get rid of useless ip_vs_set_state_timeout(), from Aaron Conole.
40) Speed up netns by selective calls of synchronize_net(), from
Florian Westphal.
41) Silence stack size warning gcc in 32-bit arch in snmp helper,
from Florian.
42) Inconditionally call nf_ct_ext_destroy(), even if we have no
extensions, to deal with the NF_NAT_MANIP_SRC case. Patch from
Liping Zhang.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Pass the new extended ACK reporting struct to all of the generic
netlink parsing functions. For now, pass NULL in almost all callers
(except for some in the core.)
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add and use nfnl_msg_type() function to replace opencoded nfnetlink
message type. I suggested this change, Arushi Singhal made an initial
patch to address this but was missing several spots.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
When we want to validate the expr's dependency or hooks, we must do two
things to accomplish it. First, write a X_validate callback function
and point ->validate to it. Second, call X_validate in init routine.
This is very common, such as fib, nat, reject expr and so on ...
It is a little ugly, since we will call X_validate in the expr's init
routine, it's better to do it in nf_tables_newexpr. So we can avoid to
do this again and again. After doing this, the second step listed above
is not useful anymore, remove them now.
Patch was tested by nftables/tests/py/nft-test.py and
nftables/tests/shell/run-tests.sh.
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
We "cache" the loaded match/target modules and reuse them, but when the
modules are removed, we still point to them. Then we may end up with
invalid memory references when using iptables-compat to add rules later.
Input the following commands will reproduce the kernel crash:
# iptables-compat -A INPUT -j LOG
# iptables-compat -D INPUT -j LOG
# rmmod xt_LOG
# iptables-compat -A INPUT -j LOG
BUG: unable to handle kernel paging request at ffffffffa05a9010
IP: [<ffffffff813f783e>] strcmp+0xe/0x30
Call Trace:
[<ffffffffa05acc43>] nft_target_select_ops+0x83/0x1f0 [nft_compat]
[<ffffffffa058a177>] nf_tables_expr_parse+0x147/0x1f0 [nf_tables]
[<ffffffffa058e541>] nf_tables_newrule+0x301/0x810 [nf_tables]
[<ffffffff8141ca00>] ? nla_parse+0x20/0x100
[<ffffffffa057fa8f>] nfnetlink_rcv+0x33f/0x53d [nfnetlink]
[<ffffffffa057f94b>] ? nfnetlink_rcv+0x1fb/0x53d [nfnetlink]
[<ffffffff817116b8>] netlink_unicast+0x178/0x220
[<ffffffff81711a5b>] netlink_sendmsg+0x2fb/0x3a0
[<ffffffff816b7fc8>] sock_sendmsg+0x38/0x50
[<ffffffff816b8a7e>] ___sys_sendmsg+0x28e/0x2a0
[<ffffffff816bcb7e>] ? release_sock+0x1e/0xb0
[<ffffffff81804ac5>] ? _raw_spin_unlock_bh+0x35/0x40
[<ffffffff816bcbe2>] ? release_sock+0x82/0xb0
[<ffffffff816b93d4>] __sys_sendmsg+0x54/0x90
[<ffffffff816b9422>] SyS_sendmsg+0x12/0x20
[<ffffffff81805172>] entry_SYSCALL_64_fastpath+0x1a/0xa9
So when nobody use the related match/target module, there's no need to
"cache" it. And nft_[match|target]_release are useless anymore, remove
them.
Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
If the user specify the invalid NFTA_MATCH_INFO/NFTA_TARGET_INFO attr
or memory alloc fail, we should call module_put to the related match
or target. Otherwise, we cannot remove the module even nobody use it.
Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
We copy according to ->target|matchsize, so check that the netlink attribute
(which can include padding and might be larger) contains enough data.
Reported-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Fix lookup of existing match/target structures in the corresponding list
by skipping the family check if NFPROTO_UNSPEC is used.
This is resulting in the allocation and insertion of one match/target
structure for each use of them. So this not only bloats memory
consumption but also severely affects the time to reload the ruleset
from the iptables-compat utility.
After this patch, iptables-compat-restore and iptables-compat take
almost the same time to reload large rulesets.
Fixes: 0ca743a559 ("netfilter: nf_tables: add compatibility layer for x_tables")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Currently, we have four xtables extensions that cannot be used from the
xt over nft compat layer. The problem is that they need real access to
the full blown xt_entry to validate that the rule comes with the right
dependencies. This check was introduced to overcome the lack of
sufficient userspace dependency validation in iptables.
To resolve this problem, this patch introduces a new field to the
xt_tgchk_param structure that tell us if the extension is run from
nft_compat context.
The three affected extensions are:
1) CLUSTERIP, this target has been superseded by xt_cluster. So just
bail out by returning -EINVAL.
2) TCPMSS. Relax the checking when used from nft_compat. If used with
the wrong configuration, it will corrupt !syn packets by adding TCP
MSS option.
3) ebt_stp. Relax the check to make sure it uses the reserved
destination MAC address for STP.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Tested-by: Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com>
Replace the array of registers passed to expressions by a struct nft_regs,
containing the verdict as a seperate member, which aliases to the
NFT_REG_VERDICT register.
This is needed to seperate the verdict from the data registers completely,
so their size can be changed.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
More recent GCC warns about two kinds of switch statement uses:
1) Switching on an enumeration, but not having an explicit case
statement for all members of the enumeration. To show the
compiler this is intentional, we simply add a default case
with nothing more than a break statement.
2) Switching on a boolean value. I think this warning is dumb
but nevertheless you get it wholesale with -Wswitch.
This patch cures all such warnings in netfilter.
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
Conflicts:
net/netfilter/nf_tables_core.c
The nf_tables_core.c conflict was resolved using a conflict resolution
from Stephen Rothwell as a guide.
Signed-off-by: David S. Miller <davem@davemloft.net>
ip6tables extensions check for this flag to restrict match/target to a
given protocol. Without this flag set, SYNPROXY6 returns an error.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Patrick McHardy <kaber@trash.net>
Conflicts:
drivers/net/ethernet/cadence/macb.c
Overlapping changes in macb driver, mostly fixes and cleanups
in 'net' overlapping with the integration of at91_ether into
macb in 'net-next'.
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/net/ethernet/rocker/rocker.c
The rocker commit was two overlapping changes, one to rename
the ->vport member to ->pport, and another making the bitmask
expression use '1ULL' instead of plain '1'.
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds support to arptables extensions from nft_compat.
Signed-off-by: Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Use u16 for protocol and then cast it to __be16
>> net/netfilter/nft_compat.c:140:37: sparse: incorrect type in assignment (different base types)
net/netfilter/nft_compat.c:140:37: expected restricted __be16 [usertype] ethproto
net/netfilter/nft_compat.c:140:37: got unsigned char [unsigned] [usertype] proto
>> net/netfilter/nft_compat.c:351:37: sparse: incorrect type in assignment (different base types)
net/netfilter/nft_compat.c:351:37: expected restricted __be16 [usertype] ethproto
net/netfilter/nft_compat.c:351:37: got unsigned char [unsigned] [usertype] proto
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Pablo Neira Ayuso says:
====================
Netfilter/IPVS fixes for net
The following patchset contains updates for your net tree, they are:
1) Fix removal of destination in IPVS when the new mixed family support
is used, from Alexey Andriyanov via Simon Horman.
2) Fix module refcount undeflow in nft_compat when reusing a match /
target.
3) Fix iptables-restore when the recent match is used with a new hitcount
that exceeds threshold, from Florian Westphal.
4) Fix stack corruption in xt_socket due to using stack storage to save
the inner IPv6 header, from Eric Dumazet.
I'll follow up soon with another batch with more fixes that are still
cooking.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch extends nft_compat to support ebtables extensions.
ebtables verdict codes are translated to the ones used by the nf_tables engine,
so we can properly use ebtables target extensions from nft_compat.
This patch extends previous work by Giuseppe Longo <giuseppelng@gmail.com>.
Signed-off-by: Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Instead of the match->name, which is of course not relevant.
Fixes: f3f5dde ("netfilter: nft_compat: validate chain type in match/target")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Check for nat chain dependency only, which is the one that can
actually crash the kernel. Don't care if mangle, filter and security
specific match and targets are used out of their scope, they are
harmless.
This restores iptables-compat with mangle specific match/target when
used out of the OUTPUT chain, that are actually emulated through filter
chains, which broke when performing strict validation.
Fixes: f3f5dde ("netfilter: nft_compat: validate chain type in match/target")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The code looks for an already loaded target, and the correct list to search
is nft_target_list, not nft_match_list.
Signed-off-by: Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Florian Westphal