[ Upstream commit 21d5e07819 ]
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>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 732a8049f3 upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8bdf164744 upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b8e9dc1c75 upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.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>
We have to validate the real chain type to ensure that matches/targets
are not used out from their scope (eg. MASQUERADE in nat chain type).
The existing validation relies on the table name, but this is not
sufficient since userspace can fool us by using the appropriate table
name with a different chain type.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Set hook_mask to zero for non-base chains, otherwise people may hit
bogus errors from the xt_check_target() and xt_check_match() when
validating the uninitialized hook_mask.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This code was based on the wrong asumption that you can probe based
on the match/target private size that we get from userspace. This
doesn't work at all when you have to dump the info back to userspace
since you don't know what word size the userspace utility is using.
Currently, the extensions that require arch compat are limit match
and the ebt_mark match/target. The standard targets are not used by
the nft-xt compat layer, so they are not affected. We can work around
this limitation with a new revision that uses arch agnostic types.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Otherwise, the reference to external objects (eg. modules) are not
released when the rules are removed.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
In order to fix set destruction notifications and get rid of unnecessary
members in private data structures, pass the context to expressions'
destructor functions again.
In order to do so, replace various members in the nft_rule_trans structure
by the full context.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Add support to register chains to multiple hooks for different address
families for mixed IPv4/IPv6 tables.
Signed-off-by: Patrick McHardy <kaber@trash.net>
The patch 0ca743a55991: "netfilter: nf_tables: add compatibility
layer for x_tables", leads to the following Smatch
warning: "net/netfilter/nft_compat.c:140 nft_parse_compat()
warn: signedness bug returning '(-34)'"
This nft_parse_compat function returns error codes but the return
type is u8 so the error codes are transformed into small positive
values. The callers don't check the return.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
We need to use the _safe version of list_for_each_entry() here otherwise
we have a use after free bug.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch adds the x_tables compatibility layer. This allows you
to use existing x_tables matches and targets from nf_tables.
This compatibility later allows us to use existing matches/targets
for features that are still missing in nf_tables. We can progressively
replace them with native nf_tables extensions. It also provides the
userspace compatibility software that allows you to express the
rule-set using the iptables syntax but using the nf_tables kernel
components.
In order to get this compatibility layer working, I've done the
following things:
* add NFNL_SUBSYS_NFT_COMPAT: this new nfnetlink subsystem is used
to query the x_tables match/target revision, so we don't need to
use the native x_table getsockopt interface.
* emulate xt structures: this required extending the struct nft_pktinfo
to include the fragment offset, which is already obtained from
ip[6]_tables and that is used by some matches/targets.
* add support for default policy to base chains, required to emulate
x_tables.
* add NFTA_CHAIN_USE attribute to obtain the number of references to
chains, required by x_tables emulation.
* add chain packet/byte counters using per-cpu.
* support 32-64 bits compat.
For historical reasons, this patch includes the following patches
that were posted in the netfilter-devel mailing list.
From Pablo Neira Ayuso:
* nf_tables: add default policy to base chains
* netfilter: nf_tables: add NFTA_CHAIN_USE attribute
* nf_tables: nft_compat: private data of target and matches in contiguous area
* nf_tables: validate hooks for compat match/target
* nf_tables: nft_compat: release cached matches/targets
* nf_tables: x_tables support as a compile time option
* nf_tables: fix alias for xtables over nftables module
* nf_tables: add packet and byte counters per chain
* nf_tables: fix per-chain counter stats if no counters are passed
* nf_tables: don't bump chain stats
* nf_tables: add protocol and flags for xtables over nf_tables
* nf_tables: add ip[6]t_entry emulation
* nf_tables: move specific layer 3 compat code to nf_tables_ipv[4|6]
* nf_tables: support 32bits-64bits x_tables compat
* nf_tables: fix compilation if CONFIG_COMPAT is disabled
From Patrick McHardy:
* nf_tables: move policy to struct nft_base_chain
* nf_tables: send notifications for base chain policy changes
From Alexander Primak:
* nf_tables: remove the duplicate NF_INET_LOCAL_OUT
From Nicolas Dichtel:
* nf_tables: fix compilation when nf-netlink is a module
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Florian Westphal