Commit Graph

4806 Commits

Author SHA1 Message Date
Taehee Yoo b25a31bf0c netfilter: nf_tables: add missing ->release_ops() in error path of newrule()
->release_ops() callback releases resources and this is used in error path.
If nf_tables_newrule() fails after ->select_ops(), it should release
resources. but it can not call ->destroy() because that should be called
after ->init().
At this point, ->release_ops() should be used for releasing resources.

Test commands:
   modprobe -rv xt_tcpudp
   iptables-nft -I INPUT -m tcp   <-- error command
   lsmod

Result:
   Module                  Size  Used by
   xt_tcpudp              20480  2      <-- it should be 0

Fixes: b8e2040063 ("netfilter: nft_compat: use .release_ops and remove list of extension")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-03-20 08:32:58 +01:00
Pablo Neira Ayuso 74710e0590 netfilter: nft_redir: fix module autoload with ip4
AF_INET4 does not exist.

Fixes: c78efc99c7 ("netfilter: nf_tables: nat: merge nft_redir protocol specific modules)"
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-03-18 16:22:49 +01:00
Pablo Neira Ayuso 8ffcd32f64 netfilter: nf_tables: bogus EBUSY in helper removal from transaction
Proper use counter updates when activating and deactivating the object,
otherwise, this hits bogus EBUSY error.

Fixes: cd5125d8f5 ("netfilter: nf_tables: split set destruction in deactivate and destroy phase")
Reported-by: Laura Garcia <nevola@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-03-18 16:22:49 +01:00
Arnd Bergmann d1fa381033 netfilter: fix NETFILTER_XT_TARGET_TEE dependencies
With NETFILTER_XT_TARGET_TEE=y and IP6_NF_IPTABLES=m, we get a link
error when referencing the NF_DUP_IPV6 module:

net/netfilter/xt_TEE.o: In function `tee_tg6':
xt_TEE.c:(.text+0x14): undefined reference to `nf_dup_ipv6'

The problem here is the 'select NF_DUP_IPV6 if IP6_NF_IPTABLES'
that forces NF_DUP_IPV6 to be =m as well rather than setting it
to =y as was intended here. Adding a soft dependency on
IP6_NF_IPTABLES avoids that broken configuration.

Fixes: 5d400a4933 ("netfilter: Kconfig: Change select IPv6 dependencies")
Cc: Máté Eckl <ecklm94@gmail.com>
Cc: Taehee Yoo <ap420073@gmail.com>
Link: https://patchwork.ozlabs.org/patch/999498/
Link: https://lore.kernel.org/patchwork/patch/960062/
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-03-18 16:21:54 +01:00
Pablo Neira Ayuso 05b7639da5 netfilter: nft_set_rbtree: check for inactive element after flag mismatch
Otherwise, we hit bogus ENOENT when removing elements.

Fixes: e701001e7c ("netfilter: nft_rbtree: allow adjacent intervals with dynamic updates")
Reported-by: Václav Zindulka <vaclav.zindulka@tlapnet.cz>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-03-18 16:21:09 +01:00
Alin Nastac 29b0b5d565 netfilter: nf_conntrack_sip: remove direct dependency on IPv6
Previous implementation was not usable with CONFIG_IPV6=m.

Fixes: a3419ce335 ("netfilter: nf_conntrack_sip: add sip_external_media logic")
Signed-off-by: Alin Nastac <alin.nastac@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-03-18 16:11:54 +01:00
Florian Westphal b8b2749865 netfilter: nf_tables: return immediately on empty commit
When running 'nft flush ruleset' while no rules exist, we will increment
the generation counter and announce a new genid to userspace, yet
nothing had changed in the first place.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-03-11 20:01:20 +01:00
Pablo Neira Ayuso 3f3a390dbd netfilter: nf_tables: use-after-free in dynamic operations
Smatch reports:

       net/netfilter/nf_tables_api.c:2167 nf_tables_expr_destroy()
        error: dereferencing freed memory 'expr->ops'

net/netfilter/nf_tables_api.c
    2162 static void nf_tables_expr_destroy(const struct nft_ctx *ctx,
    2163                                   struct nft_expr *expr)
    2164 {
    2165        if (expr->ops->destroy)
    2166                expr->ops->destroy(ctx, expr);
                                                ^^^^
--> 2167        module_put(expr->ops->type->owner);
                           ^^^^^^^^^
    2168 }

Smatch says there are three functions which free expr->ops.

Fixes: b8e2040063 ("netfilter: nft_compat: use .release_ops and remove list of extension")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-03-11 13:19:49 +01:00
Pablo Neira Ayuso 273fe3f100 netfilter: nf_tables: bogus EBUSY when deleting set after flush
Set deletion after flush coming in the same batch results in EBUSY. Add
set use counter to track the number of references to this set from
rules. We cannot rely on the list of bindings for this since such list
is still populated from the preparation phase.

Reported-by: Václav Zindulka <vaclav.zindulka@tlapnet.cz>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-03-11 13:19:24 +01:00
Pablo Neira Ayuso 40ba1d9b4d netfilter: nf_tables: fix set double-free in abort path
The abort path can cause a double-free of an anonymous set.
Added-and-to-be-aborted rule looks like this:

udp dport { 137, 138 } drop

The to-be-aborted transaction list looks like this:

newset
newsetelem
newsetelem
rule

This gets walked in reverse order, so first pass disables the rule, the
set elements, then the set.

After synchronize_rcu(), we then destroy those in same order: rule, set
element, set element, newset.

Problem is that the anonymous set has already been bound to the rule, so
the rule (lookup expression destructor) already frees the set, when then
cause use-after-free when trying to delete the elements from this set,
then try to free the set again when handling the newset expression.

Rule releases the bound set in first place from the abort path, this
causes the use-after-free on set element removal when undoing the new
element transactions. To handle this, skip new element transaction if
set is bound from the abort path.

This is still causes the use-after-free on set element removal.  To
handle this, remove transaction from the list when the set is already
bound.

Joint work with Florian Westphal.

Fixes: f6ac858589 ("netfilter: nf_tables: unbind set in rule from commit path")
Bugzilla: https://bugzilla.netfilter.org/show_bug.cgi?id=1325
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-03-08 16:41:18 +01:00
Florian Westphal 46f7487e16 netfilter: nat: don't register device notifier twice
Otherwise, we get notifier list corruption.

This is the most simple fix: remove the device notifier call chain
from the ipv6 masquerade register function and handle it only
in the ipv4 version.

The better fix is merge
nf_nat_masquerade_ipv4/6_(un)register_notifier
  into a single
nf_nat_masquerade_(un)register_notifiers

but to do this its needed to first merge the two masquerade modules
into a single xt_MASQUERADE.

Furthermore, we need to use different refcounts for ipv4/ipv6
until we can merge MASQUERADE.

Fixes: d1aca8ab31 ("netfilter: nat: merge ipv4 and ipv6 masquerade functionality")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-03-08 16:41:09 +01:00
Florian Westphal db8ab38880 netfilter: nf_tables: merge ipv4 and ipv6 nat chain types
Merge the ipv4 and ipv6 nat chain type. This is the last
missing piece which allows to provide inet family support
for nat in a follow patch.

The kconfig knobs for ipv4/ipv6 nat chain are removed, the
nat chain type will be built unconditionally if NFT_NAT
expression is enabled.

Before:
   text	   data	    bss	    dec	    hex	filename
   1576     896       0    2472     9a8 nft_chain_nat_ipv4.ko
   1697     896       0    2593     a21 nft_chain_nat_ipv6.ko

After:
   text	   data	    bss	    dec	    hex	filename
   1832     896       0    2728     aa8 nft_chain_nat.ko

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-03-01 14:36:59 +01:00
Florian Westphal a9ce849e78 netfilter: nf_tables: nat: merge nft_masq protocol specific modules
The family specific masq modules are way too small to warrant
an extra module, just place all of them in nft_masq.

before:
  text	   data	    bss	    dec	    hex	filename
   1001	    832	      0	   1833	    729	nft_masq.ko
    766	    896	      0	   1662	    67e	nft_masq_ipv4.ko
    764	    896	      0	   1660	    67c	nft_masq_ipv6.ko

after:
   2010	    960	      0	   2970	    b9a	nft_masq.ko

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-03-01 14:36:59 +01:00
Florian Westphal c78efc99c7 netfilter: nf_tables: nat: merge nft_redir protocol specific modules
before:
 text	   data	    bss	    dec	    hex	filename
 990	    832	      0	   1822	    71e nft_redir.ko
 697	    896	      0	   1593	    639 nft_redir_ipv4.ko
 713	    896	      0	   1609	    649	nft_redir_ipv6.ko

after:
 text	   data	    bss	    dec	    hex	filename
 1910	    960	      0	   2870	    b36	nft_redir.ko

size is reduced, all helpers from nft_redir.ko can be made static.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-03-01 14:36:58 +01:00
Sami Tolvanen 20fdaf6e1e netfilter: xt_IDLETIMER: fix sysfs callback function type
Use struct device_attribute instead of struct idletimer_tg_attr, and
the correct callback function type to avoid indirect call mismatches
with Control Flow Integrity checking.

Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-03-01 14:36:57 +01:00
Li RongQing 2e7b162c5e netfilter: nf_conntrack: ensure that CONNTRACK_LOCKS is power of 2
CONNTRACK_LOCKS is divisor when computer array index, if it is power of
2, compiler will optimize modulo operation as bitwise AND, or else
modulo will lower performance.

Suggested-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-03-01 14:36:46 +01:00
Li RongQing a9f5e78c40 netfilter: nf_tables: check the result of dereferencing base_chain->stats
Check the result of dereferencing base_chain->stats, instead of result
of this_cpu_ptr with NULL.

base_chain->stats maybe be changed to NULL when a chain is updated and a
new NULL counter can be attached.

And we do not need to check returning of this_cpu_ptr since
base_chain->stats is from percpu allocator if it is non-NULL,
this_cpu_ptr returns a valid value.

And fix two sparse error by replacing rcu_access_pointer and
rcu_dereference with READ_ONCE under rcu_read_lock.

Thanks for Eric's help to finish this patch.

Fixes: 009240940e ("netfilter: nf_tables: don't assume chain stats are set when jumplabel is set")
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Zhang Yu <zhangyu31@baidu.com>
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-03-01 14:34:24 +01:00
Xin Long f52a40fb41 ipvs: get sctphdr by sctphoff in sctp_csum_check
sctp_csum_check() is called by sctp_s/dnat_handler() where it calls
skb_make_writable() to ensure sctphdr to be linearized.

So there's no need to get sctphdr by calling skb_header_pointer()
in sctp_csum_check().

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Acked-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-03-01 14:28:44 +01:00
Li RongQing 11d4dd0b20 netfilter: convert the proto argument from u8 to u16
The proto in struct xt_match and struct xt_target is u16, when
calling xt_check_target/match, their proto argument is u8,
and will cause truncation, it is harmless to ip packet, since
ip proto is u8

if a etable's match/target has proto that is u16, will cause
the check failure.

and convert be16 to short in bridge/netfilter/ebtables.c

Signed-off-by: Zhang Yu <zhangyu31@baidu.com>
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-03-01 14:28:43 +01:00
wenxu 3e511d5652 netfilter: nft_tunnel: Add dst_cache support
The metadata_dst does not initialize the dst_cache field, this causes
problems to ip_md_tunnel_xmit() since it cannot use this cache, hence,
Triggering a route lookup for every packet.

Signed-off-by: wenxu <wenxu@ucloud.cn>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-03-01 14:25:06 +01:00
Florian Westphal be0502a3f2 netfilter: conntrack: tcp: only close if RST matches exact sequence
TCP resets cause instant transition from established to closed state
provided the reset is in-window.  Endpoints that implement RFC 5961
require resets to match the next expected sequence number.
RST segments that are in-window (but that do not match RCV.NXT) are
ignored, and a "challenge ACK" is sent back.

Main problem for conntrack is that its a middlebox, i.e.  whereas an end
host might have ACK'd SEQ (and would thus accept an RST with this
sequence number), conntrack might not have seen this ACK (yet).

Therefore we can't simply flag RSTs with non-exact match as invalid.

This updates RST processing as follows:

1. If the connection is in a state other than ESTABLISHED, nothing is
   changed, RST is subject to normal in-window check.

2. If the RSTs sequence number either matches exactly RCV.NXT,
   connection state moves to CLOSE.

3. The same applies if the RST sequence number aligns with a previous
   packet in the same direction.

In all other cases, the connection remains in ESTABLISHED state.
If the normal-in-window check passes, the timeout will be lowered
to that of CLOSE.

If the peer sends a challenge ack, connection timeout will be reset.

If the challenge ACK triggers another RST (RST was valid after all),
this 2nd RST will match expected sequence and conntrack state changes to
CLOSE.

If no challenge ACK is received, the connection will time out after
CLOSE seconds (10 seconds by default), just like without this patch.

Packetdrill test case:

0.000 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3
0.000 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
0.000 bind(3, ..., ...) = 0
0.000 listen(3, 1) = 0

0.100 < S 0:0(0) win 32792 <mss 1460,sackOK,nop,nop,nop,wscale 7>
0.100 > S. 0:0(0) ack 1 win 64240 <mss 1460,nop,nop,sackOK,nop,wscale 7>
0.200 < . 1:1(0) ack 1 win 257
0.200 accept(3, ..., ...) = 4

// Receive a segment.
0.210 < P. 1:1001(1000) ack 1 win 46
0.210 > . 1:1(0) ack 1001

// Application writes 1000 bytes.
0.250 write(4, ..., 1000) = 1000
0.250 > P. 1:1001(1000) ack 1001

// First reset, old sequence. Conntrack (correctly) considers this
// invalid due to failed window validation (regardless of this patch).
0.260 < R  2:2(0) ack 1001 win 260

// 2nd reset, but too far ahead sequence.  Same: correctly handled
// as invalid.
0.270 < R 99990001:99990001(0) ack 1001 win 260

// in-window, but not exact sequence.
// Current Linux kernels might reply with a challenge ack, and do not
// remove connection.
// Without this patch, conntrack state moves to CLOSE.
// With patch, timeout is lowered like CLOSE, but connection stays
// in ESTABLISHED state.
0.280 < R 1010:1010(0) ack 1001 win 260

// Expect challenge ACK
0.281 > . 1001:1001(0) ack 1001 win 501

// With or without this patch, RST will cause connection
// to move to CLOSE (sequence number matches)
// 0.282 < R 1001:1001(0) ack 1001 win 260

// ACK
0.300 < . 1001:1001(0) ack 1001 win 257

// more data could be exchanged here, connection
// is still established

// Client closes the connection.
0.610 < F. 1001:1001(0) ack 1001 win 260
0.650 > . 1001:1001(0) ack 1002

// Close the connection without reading outstanding data
0.700 close(4) = 0

// so one more reset.  Will be deemed acceptable with patch as well:
// connection is already closing.
0.701 > R. 1001:1001(0) ack 1002 win 501
// End packetdrill test case.

With patch, this generates following conntrack events:
   [NEW] 120 SYN_SENT src=10.0.2.1 dst=10.0.0.1 sport=5437 dport=80 [UNREPLIED]
[UPDATE] 60 SYN_RECV src=10.0.2.1 dst=10.0.0.1 sport=5437 dport=80
[UPDATE] 432000 ESTABLISHED src=10.0.2.1 dst=10.0.0.1 sport=5437 dport=80 [ASSURED]
[UPDATE] 120 FIN_WAIT src=10.0.2.1 dst=10.0.0.1 sport=5437 dport=80 [ASSURED]
[UPDATE] 60 CLOSE_WAIT src=10.0.2.1 dst=10.0.0.1 sport=5437 dport=80 [ASSURED]
[UPDATE] 10 CLOSE src=10.0.2.1 dst=10.0.0.1 sport=5437 dport=80 [ASSURED]

Without patch, first RST moves connection to close, whereas socket state
does not change until FIN is received.
   [NEW] 120 SYN_SENT src=10.0.2.1 dst=10.0.0.1 sport=5141 dport=80 [UNREPLIED]
[UPDATE] 60 SYN_RECV src=10.0.2.1 dst=10.0.0.1 sport=5141 dport=80
[UPDATE] 432000 ESTABLISHED src=10.0.2.1 dst=10.0.0.1 sport=5141 dport=80 [ASSURED]
[UPDATE] 10 CLOSE src=10.0.2.1 dst=10.0.0.1 sport=5141 dport=80 [ASSURED]

Cc: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-03-01 14:19:31 +01:00
Andrea Claudi f25a9b8515 ipvs: change some data types from int to bool
Change the data type of the following variables from int to bool
across ipvs code:

  - found
  - loop
  - need_full_dest
  - need_full_svc
  - payload_csum

Also change the following functions to use bool full_entry param
instead of int:

  - ip_vs_genl_parse_dest()
  - ip_vs_genl_parse_service()

This patch does not change any functionality but makes the source
code slightly easier to read.

Signed-off-by: Andrea Claudi <aclaudi@redhat.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Acked-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-03-01 14:19:04 +01:00
Pablo Neira Ayuso 123f89c8aa netfilter: nft_set_hash: remove nft_hash_key()
hashtable is never used for 2-byte keys, remove nft_hash_key().

Fixes: e240cd0df4 ("netfilter: nf_tables: place all set backends in one single module")
Reported-by: Florian Westphal <fw@strlen.de>
Tested-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-02-27 11:08:32 +01:00
Pablo Neira Ayuso a01cbae57e netfilter: nft_set_hash: bogus element self comparison from deactivation path
Use the element from the loop iteration, not the same element we want to
deactivate otherwise this branch always evaluates true.

Fixes: 6c03ae210c ("netfilter: nft_set_hash: add non-resizable hashtable implementation")
Reported-by: Florian Westphal <fw@strlen.de>
Tested-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-02-27 11:08:31 +01:00
Pablo Neira Ayuso 3b02b0adc2 netfilter: nft_set_hash: fix lookups with fixed size hash on big endian
Call jhash_1word() for the 4-bytes key case from the insertion and
deactivation path, otherwise big endian arch set lookups fail.

Fixes: 446a8268b7 ("netfilter: nft_set_hash: add lookup variant for fixed size hashtable")
Reported-by: Florian Westphal <fw@strlen.de>
Tested-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-02-27 11:08:31 +01:00
Li RongQing 35acfbab6e netfilter: remove unneeded switch fall-through
Empty case is fine and does not switch fall-through

Signed-off-by: Li RongQing <lirongqing@baidu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-02-27 11:03:59 +01:00
Florian Westphal cc16921351 netfilter: conntrack: avoid same-timeout update
No need to dirty a cache line if timeout is unchanged.
Also, WARN() is useless here: we crash on 'skb->len' access
if skb is NULL.

Last, ct->timeout is u32, not 'unsigned long' so adapt the
function prototype accordingly.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-02-27 10:58:21 +01:00
Florian Westphal d2c5c103b1 netfilter: nat: remove nf_nat_l3proto.h and nf_nat_core.h
The l3proto name is gone, its header file is the last trace.
While at it, also remove nf_nat_core.h, its very small and all users
include nf_nat.h too.

before:
   text    data     bss     dec     hex filename
  22948    1612    4136   28696    7018 nf_nat.ko

after removal of l3proto register/unregister functions:
   text	   data	    bss	    dec	    hex	filename
  22196	   1516	   4136	  27848	   6cc8 nf_nat.ko

checkpatch complains about overly long lines, but line breaks
do not make things more readable and the line length gets smaller
here, not larger.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-02-27 10:54:08 +01:00
Florian Westphal d6c4c8ffb5 netfilter: nat: remove l3proto struct
All l3proto function pointers have been removed.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-02-27 10:53:57 +01:00
Florian Westphal dac3fe7259 netfilter: nat: remove csum_recalc hook
We can now use direct calls.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-02-27 10:53:47 +01:00
Florian Westphal 03fe5efc4c netfilter: nat: remove csum_update hook
We can now use direct calls.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-02-27 10:53:35 +01:00
Florian Westphal 2e666b229d netfilter: nat: remove l3 manip_pkt hook
We can now use direct calls.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-02-27 10:53:05 +01:00
Florian Westphal 14cb1a6e29 netfilter: nat: remove nf_nat_l4proto.h
after ipv4/6 nat tracker merge, there are no external callers, so
make last function static and remove the header.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-02-27 10:52:47 +01:00
Florian Westphal 3bf195ae60 netfilter: nat: merge nf_nat_ipv4,6 into nat core
before:
   text    data     bss     dec     hex filename
  16566    1576    4136   22278    5706 nf_nat.ko
   3598	    844	      0	   4442	   115a	nf_nat_ipv6.ko
   3187	    844	      0	   4031	    fbf	nf_nat_ipv4.ko

after:
   text    data     bss     dec     hex filename
  22948    1612    4136   28696    7018 nf_nat.ko

... with ipv4/v6 nat now provided directly via nf_nat.ko.

Also changes:
       ret = nf_nat_ipv4_fn(priv, skb, state);
       if (ret != NF_DROP && ret != NF_STOLEN &&
into
	if (ret != NF_ACCEPT)
		return ret;

everywhere.

The nat hooks never should return anything other than
ACCEPT or DROP (and the latter only in rare error cases).

The original code uses multi-line ANDing including assignment-in-if:
        if (ret != NF_DROP && ret != NF_STOLEN &&
           !(IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) &&
            (ct = nf_ct_get(skb, &ctinfo)) != NULL) {

I removed this while moving, breaking those in separate conditionals
and moving the assignments into extra lines.

checkpatch still generates some warnings:
 1. Overly long lines (of moved code).
    Breaking them is even more ugly. so I kept this as-is.
 2. use of extern function declarations in a .c file.
    This is necessary evil, we must call
    nf_nat_l3proto_register() from the nat core now.
    All l3proto related functions are removed later in this series,
    those prototypes are then removed as well.

v2: keep empty nf_nat_ipv6_csum_update stub for CONFIG_IPV6=n case.
v3: remove IS_ENABLED(NF_NAT_IPV4/6) tests, NF_NAT_IPVx toggles
    are removed here.
v4: also get rid of the assignments in conditionals.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-02-27 10:49:55 +01:00
Florian Westphal 096d09067a netfilter: nat: move nlattr parse and xfrm session decode to core
None of these functions calls any external functions, moving them allows
to avoid both the indirection and a need to export these symbols.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-02-27 10:49:42 +01:00
Florian Westphal d1aca8ab31 netfilter: nat: merge ipv4 and ipv6 masquerade functionality
Before:
   text	   data	    bss	    dec	    hex	filename
  13916	   1412	   4128	  19456	   4c00	nf_nat.ko
   4510	    968	      4	   5482	   156a	nf_nat_ipv4.ko
   5146	    944	      8	   6098	   17d2	nf_nat_ipv6.ko

After:
   text	   data	    bss	    dec	    hex	filename
  16566	   1576	   4136	  22278	   5706	nf_nat.ko
   3187	    844	      0	   4031	    fbf	nf_nat_ipv4.ko
   3598	    844	      0	   4442	   115a	nf_nat_ipv6.ko

... so no drastic changes in combined size.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-02-27 10:49:24 +01:00
Florian Tham 4283428e49 netfilter: nf_conntrack_amanda: add support for STATE streams
The Amanda CONNECT command has been updated to establish an optional
fourth connection [0]. Previously, a CONNECT command would look like:

    CONNECT DATA port0 MESG port1 INDEX port2

nf_conntrack_amanda analyses the CONNECT command string in order to
learn the port numbers of the related DATA, MESG and INDEX streams. As
of amanda v3.4, the CONNECT command can advertise an additional port:

    CONNECT DATA port0 MESG port1 INDEX port2 STATE port3

The new STATE stream is not handled, thus the connection on the STATE
port cannot be established.

The patch adds support for STATE streams to the amanda conntrack helper.

I tested with max_expected = 3, leaving the other patch hunks
unmodified. Amanda reports "connection refused" and aborts. After I set
max_expected to 4, the backup completes successfully.

[0] 3b8384fc9f (diff-711e502fc81a65182c0954765b42919eR456)

Signed-off-by: Florian Tham <tham@fidion.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-02-27 10:46:39 +01:00
Pablo Neira Ayuso b8e2040063 netfilter: nft_compat: use .release_ops and remove list of extension
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>
2019-02-27 10:41:24 +01:00
David S. Miller 375ca548f7 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Two easily resolvable overlapping change conflicts, one in
TCP and one in the eBPF verifier.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-20 00:34:07 -08:00
David S. Miller 8bbed40f10 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next
Pablo Neira Ayuso says:

====================
Netfilter/IPVS updates for net-next

The following patchset contains Netfilter/IPVS updates for you net-next
tree:

1) Missing NFTA_RULE_POSITION_ID netlink attribute validation,
   from Phil Sutter.

2) Restrict matching on tunnel metadata to rx/tx path, from wenxu.

3) Avoid indirect calls for IPV6=y, from Florian Westphal.

4) Add two indirections to prepare merger of IPV4 and IPV6 nat
   modules, from Florian Westphal.

5) Broken indentation in ctnetlink, from Colin Ian King.

6) Patches to use struct_size() from netfilter and IPVS,
   from Gustavo A. R. Silva.

7) Display kernel splat only once in case of racing to confirm
   conntrack from bridge plus nfqueue setups, from Chieh-Min Wang.

8) Skip checksum validation for layer 4 protocols that don't need it,
   patch from Alin Nastac.

9) Sparse warning due to symbol that should be static in CLUSTERIP,
   from Wei Yongjun.

10) Add new toggle to disable SDP payload translation when media
    endpoint is reachable though the same interface as the signalling
    peer, from Alin Nastac.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-18 11:38:30 -08:00
Alin Nastac a3419ce335 netfilter: nf_conntrack_sip: add sip_external_media logic
When enabled, the sip_external_media logic will leave SDP
payload untouched when it detects that interface towards INVITEd
party is the same with the one towards media endpoint.

The typical scenario for this logic is when a LAN SIP agent has more
than one IP address (uses a different address for media streams than
the one used on signalling stream) and it also forwards calls to a
voice mailbox located on the WAN side. In such case sip_direct_media
must be disabled (so normal calls could be handled by the SIP
helper), but media streams that are not traversing this router must
also be excluded from address translation (e.g. call forwards).

Signed-off-by: Alin Nastac <alin.nastac@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-02-16 10:49:12 +01:00
Andrea Claudi c93a49b976 ipvs: fix warning on unused variable
When CONFIG_IP_VS_IPV6 is not defined, build produced this warning:

net/netfilter/ipvs/ip_vs_ctl.c:899:6: warning: unused variable ‘ret’ [-Wunused-variable]
  int ret = 0;
      ^~~

Fix this by moving the declaration of 'ret' in the CONFIG_IP_VS_IPV6
section in the same function.

While at it, drop its unneeded initialisation.

Fixes: 098e13f5b2 ("ipvs: fix dependency on nf_defrag_ipv6")
Reported-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Andrea Claudi <aclaudi@redhat.com>
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-02-16 10:41:42 +01:00
David S. Miller 3313da8188 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
The netfilter conflicts were rather simple overlapping
changes.

However, the cls_tcindex.c stuff was a bit more complex.

On the 'net' side, Cong is fixing several races and memory
leaks.  Whilst on the 'net-next' side we have Vlad adding
the rtnl-ness support.

What I've decided to do, in order to resolve this, is revert the
conversion over to using a workqueue that Cong did, bringing us back
to pure RCU.  I did it this way because I believe that either Cong's
races don't apply with have Vlad did things, or Cong will have to
implement the race fix slightly differently.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-15 12:38:38 -08:00
Pablo Neira Ayuso 23b7ca4f74 netfilter: nf_tables: fix flush after rule deletion in the same batch
Flush after rule deletion bogusly hits -ENOENT. Skip rules that have
been already from nft_delrule_by_chain() which is always called from the
flush path.

Fixes: cf9dc09d09 ("netfilter: nf_tables: fix missing rules flushing per table")
Reported-by: Phil Sutter <phil@nwl.cc>
Acked-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-02-15 15:32:32 +01:00
Pablo Neira Ayuso 753c111f65 netfilter: nft_compat: use-after-free when deleting targets
Fetch pointer to module before target object is released.

Fixes: 29e3880109 ("netfilter: nf_tables: fix use-after-free when deleting compat expressions")
Fixes: 0ca743a559 ("netfilter: nf_tables: add compatibility layer for x_tables")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-02-13 18:14:54 +01:00
Andrea Claudi 098e13f5b2 ipvs: fix dependency on nf_defrag_ipv6
ipvs relies on nf_defrag_ipv6 module to manage IPv6 fragmentation,
but lacks proper Kconfig dependencies and does not explicitly
request defrag features.

As a result, if netfilter hooks are not loaded, when IPv6 fragmented
packet are handled by ipvs only the first fragment makes through.

Fix it properly declaring the dependency on Kconfig and registering
netfilter hooks on ip_vs_add_service() and ip_vs_new_dest().

Reported-by: Li Shuang <shuali@redhat.com>
Signed-off-by: Andrea Claudi <aclaudi@redhat.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Acked-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-02-12 11:24:01 +01:00
Chieh-Min Wang 13f5251fd1 netfilter: conntrack: fix cloned unconfirmed skb->_nfct race in __nf_conntrack_confirm
For bridge(br_flood) or broadcast/multicast packets, they could clone
skb with unconfirmed conntrack which break the rule that unconfirmed
skb->_nfct is never shared.  With nfqueue running on my system, the race
can be easily reproduced with following warning calltrace:

[13257.707525] CPU: 0 PID: 12132 Comm: main Tainted: P        W       4.4.60 #7744
[13257.707568] Hardware name: Qualcomm (Flattened Device Tree)
[13257.714700] [<c021f6dc>] (unwind_backtrace) from [<c021bce8>] (show_stack+0x10/0x14)
[13257.720253] [<c021bce8>] (show_stack) from [<c0449e10>] (dump_stack+0x94/0xa8)
[13257.728240] [<c0449e10>] (dump_stack) from [<c022a7e0>] (warn_slowpath_common+0x94/0xb0)
[13257.735268] [<c022a7e0>] (warn_slowpath_common) from [<c022a898>] (warn_slowpath_null+0x1c/0x24)
[13257.743519] [<c022a898>] (warn_slowpath_null) from [<c06ee450>] (__nf_conntrack_confirm+0xa8/0x618)
[13257.752284] [<c06ee450>] (__nf_conntrack_confirm) from [<c0772670>] (ipv4_confirm+0xb8/0xfc)
[13257.761049] [<c0772670>] (ipv4_confirm) from [<c06e7a60>] (nf_iterate+0x48/0xa8)
[13257.769725] [<c06e7a60>] (nf_iterate) from [<c06e7af0>] (nf_hook_slow+0x30/0xb0)
[13257.777108] [<c06e7af0>] (nf_hook_slow) from [<c07f20b4>] (br_nf_post_routing+0x274/0x31c)
[13257.784486] [<c07f20b4>] (br_nf_post_routing) from [<c06e7a60>] (nf_iterate+0x48/0xa8)
[13257.792556] [<c06e7a60>] (nf_iterate) from [<c06e7af0>] (nf_hook_slow+0x30/0xb0)
[13257.800458] [<c06e7af0>] (nf_hook_slow) from [<c07e5580>] (br_forward_finish+0x94/0xa4)
[13257.808010] [<c07e5580>] (br_forward_finish) from [<c07f22ac>] (br_nf_forward_finish+0x150/0x1ac)
[13257.815736] [<c07f22ac>] (br_nf_forward_finish) from [<c06e8df0>] (nf_reinject+0x108/0x170)
[13257.824762] [<c06e8df0>] (nf_reinject) from [<c06ea854>] (nfqnl_recv_verdict+0x3d8/0x420)
[13257.832924] [<c06ea854>] (nfqnl_recv_verdict) from [<c06e940c>] (nfnetlink_rcv_msg+0x158/0x248)
[13257.841256] [<c06e940c>] (nfnetlink_rcv_msg) from [<c06e5564>] (netlink_rcv_skb+0x54/0xb0)
[13257.849762] [<c06e5564>] (netlink_rcv_skb) from [<c06e4ec8>] (netlink_unicast+0x148/0x23c)
[13257.858093] [<c06e4ec8>] (netlink_unicast) from [<c06e5364>] (netlink_sendmsg+0x2ec/0x368)
[13257.866348] [<c06e5364>] (netlink_sendmsg) from [<c069fb8c>] (sock_sendmsg+0x34/0x44)
[13257.874590] [<c069fb8c>] (sock_sendmsg) from [<c06a03dc>] (___sys_sendmsg+0x1ec/0x200)
[13257.882489] [<c06a03dc>] (___sys_sendmsg) from [<c06a11c8>] (__sys_sendmsg+0x3c/0x64)
[13257.890300] [<c06a11c8>] (__sys_sendmsg) from [<c0209b40>] (ret_fast_syscall+0x0/0x34)

The original code just triggered the warning but do nothing. It will
caused the shared conntrack moves to the dying list and the packet be
droppped (nf_ct_resolve_clash returns NF_DROP for dying conntrack).

- Reproduce steps:

+----------------------------+
|          br0(bridge)       |
|                            |
+-+---------+---------+------+
  | eth0|   | eth1|   | eth2|
  |     |   |     |   |     |
  +--+--+   +--+--+   +---+-+
     |         |          |
     |         |          |
  +--+-+     +-+--+    +--+-+
  | PC1|     | PC2|    | PC3|
  +----+     +----+    +----+

iptables -A FORWARD -m mark --mark 0x1000000/0x1000000 -j NFQUEUE --queue-num 100 --queue-bypass

ps: Our nfq userspace program will set mark on packets whose connection
has already been processed.

PC1 sends broadcast packets simulated by hping3:

hping3 --rand-source --udp 192.168.1.255 -i u100

- Broadcast racing flow chart is as follow:

br_handle_frame
  BR_HOOK(NFPROTO_BRIDGE, NF_BR_PRE_ROUTING, br_handle_frame_finish)
  // skb->_nfct (unconfirmed conntrack) is constructed at PRE_ROUTING stage
  br_handle_frame_finish
    // check if this packet is broadcast
    br_flood_forward
      br_flood
        list_for_each_entry_rcu(p, &br->port_list, list) // iterate through each port
          maybe_deliver
            deliver_clone
              skb = skb_clone(skb)
              __br_forward
                BR_HOOK(NFPROTO_BRIDGE, NF_BR_FORWARD,...)
                // queue in our nfq and received by our userspace program
                // goto __nf_conntrack_confirm with process context on CPU 1
    br_pass_frame_up
      BR_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_IN,...)
      // goto __nf_conntrack_confirm with softirq context on CPU 0

Because conntrack confirm can happen at both INPUT and POSTROUTING
stage.  So with NFQUEUE running, skb->_nfct with the same unconfirmed
conntrack could race on different core.

This patch fixes a repeating kernel splat, now it is only displayed
once.

Signed-off-by: Chieh-Min Wang <chiehminw@synology.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-02-12 11:14:51 +01:00
Gustavo A. R. Silva 6ca64ef37d netfilter: xt_recent: Use struct_size() in kvzalloc()
One of the more common cases of allocation size calculations is finding
the size of a structure that has a zero-sized array at the end, along
with memory for some number of elements for that array. For example:

struct foo {
    int stuff;
    void *entry[];
};

size = sizeof(struct foo) + count * sizeof(void *);
instance = alloc(size, GFP_KERNEL)

Instead of leaving these open-coded and prone to type mistakes, we can
now use the new struct_size() helper:

size = struct_size(instance, entry, count);
instance = alloc(size, GFP_KERNEL)

Notice that, in this case, variable sz is not necessary, hence it is
removed.

This code was detected with the help of Coccinelle.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-02-12 00:39:39 +01:00
Gustavo A. R. Silva 6fde9df6b7 ipvs: Use struct_size() helper
One of the more common cases of allocation size calculations is finding
the size of a structure that has a zero-sized array at the end, along
with memory for some number of elements for that array. For example:

struct foo {
    int stuff;
    struct boo entry[];
};

size = sizeof(struct foo) + count * sizeof(struct boo);
instance = alloc(size, GFP_KERNEL)

Instead of leaving these open-coded and prone to type mistakes, we can
now use the new struct_size() helper:

size = struct_size(instance, entry, count);

This code was detected with the help of Coccinelle.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-02-12 00:39:39 +01:00
Colin Ian King 48ab807c79 netfilter: conntrack: fix indentation issue
A statement in an if block is not indented correctly. Fix this.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-02-12 00:39:39 +01:00