Commit graph

6384 commits

Author SHA1 Message Date
Ziyang Xuan
9b5b7708ec netfilter: nf_tables: Fix potential data-race in __nft_flowtable_type_get()
commit 24225011d8 upstream.

nft_unregister_flowtable_type() within nf_flow_inet_module_exit() can
concurrent with __nft_flowtable_type_get() within nf_tables_newflowtable().
And thhere is not any protection when iterate over nf_tables_flowtables
list in __nft_flowtable_type_get(). Therefore, there is pertential
data-race of nf_tables_flowtables list entry.

Use list_for_each_entry_rcu() to iterate over nf_tables_flowtables list
in __nft_flowtable_type_get(), and use rcu_read_lock() in the caller
nft_flowtable_type_get() to protect the entire type query process.

Fixes: 3b49e2e94e ("netfilter: nf_tables: add flow table netlink frontend")
Signed-off-by: Ziyang Xuan <william.xuanziyang@huawei.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-10 16:28:25 +02:00
Pablo Neira Ayuso
4e8447a9a3 netfilter: nf_tables: flush pending destroy work before exit_net release
commit 24cea96770 upstream.

Similar to 2c9f029328 ("netfilter: nf_tables: flush pending destroy
work before netlink notifier") to address a race between exit_net and
the destroy workqueue.

The trace below shows an element to be released via destroy workqueue
while exit_net path (triggered via module removal) has already released
the set that is used in such transaction.

[ 1360.547789] BUG: KASAN: slab-use-after-free in nf_tables_trans_destroy_work+0x3f5/0x590 [nf_tables]
[ 1360.547861] Read of size 8 at addr ffff888140500cc0 by task kworker/4:1/152465
[ 1360.547870] CPU: 4 PID: 152465 Comm: kworker/4:1 Not tainted 6.8.0+ #359
[ 1360.547882] Workqueue: events nf_tables_trans_destroy_work [nf_tables]
[ 1360.547984] Call Trace:
[ 1360.547991]  <TASK>
[ 1360.547998]  dump_stack_lvl+0x53/0x70
[ 1360.548014]  print_report+0xc4/0x610
[ 1360.548026]  ? __virt_addr_valid+0xba/0x160
[ 1360.548040]  ? __pfx__raw_spin_lock_irqsave+0x10/0x10
[ 1360.548054]  ? nf_tables_trans_destroy_work+0x3f5/0x590 [nf_tables]
[ 1360.548176]  kasan_report+0xae/0xe0
[ 1360.548189]  ? nf_tables_trans_destroy_work+0x3f5/0x590 [nf_tables]
[ 1360.548312]  nf_tables_trans_destroy_work+0x3f5/0x590 [nf_tables]
[ 1360.548447]  ? __pfx_nf_tables_trans_destroy_work+0x10/0x10 [nf_tables]
[ 1360.548577]  ? _raw_spin_unlock_irq+0x18/0x30
[ 1360.548591]  process_one_work+0x2f1/0x670
[ 1360.548610]  worker_thread+0x4d3/0x760
[ 1360.548627]  ? __pfx_worker_thread+0x10/0x10
[ 1360.548640]  kthread+0x16b/0x1b0
[ 1360.548653]  ? __pfx_kthread+0x10/0x10
[ 1360.548665]  ret_from_fork+0x2f/0x50
[ 1360.548679]  ? __pfx_kthread+0x10/0x10
[ 1360.548690]  ret_from_fork_asm+0x1a/0x30
[ 1360.548707]  </TASK>

[ 1360.548719] Allocated by task 192061:
[ 1360.548726]  kasan_save_stack+0x20/0x40
[ 1360.548739]  kasan_save_track+0x14/0x30
[ 1360.548750]  __kasan_kmalloc+0x8f/0xa0
[ 1360.548760]  __kmalloc_node+0x1f1/0x450
[ 1360.548771]  nf_tables_newset+0x10c7/0x1b50 [nf_tables]
[ 1360.548883]  nfnetlink_rcv_batch+0xbc4/0xdc0 [nfnetlink]
[ 1360.548909]  nfnetlink_rcv+0x1a8/0x1e0 [nfnetlink]
[ 1360.548927]  netlink_unicast+0x367/0x4f0
[ 1360.548935]  netlink_sendmsg+0x34b/0x610
[ 1360.548944]  ____sys_sendmsg+0x4d4/0x510
[ 1360.548953]  ___sys_sendmsg+0xc9/0x120
[ 1360.548961]  __sys_sendmsg+0xbe/0x140
[ 1360.548971]  do_syscall_64+0x55/0x120
[ 1360.548982]  entry_SYSCALL_64_after_hwframe+0x55/0x5d

[ 1360.548994] Freed by task 192222:
[ 1360.548999]  kasan_save_stack+0x20/0x40
[ 1360.549009]  kasan_save_track+0x14/0x30
[ 1360.549019]  kasan_save_free_info+0x3b/0x60
[ 1360.549028]  poison_slab_object+0x100/0x180
[ 1360.549036]  __kasan_slab_free+0x14/0x30
[ 1360.549042]  kfree+0xb6/0x260
[ 1360.549049]  __nft_release_table+0x473/0x6a0 [nf_tables]
[ 1360.549131]  nf_tables_exit_net+0x170/0x240 [nf_tables]
[ 1360.549221]  ops_exit_list+0x50/0xa0
[ 1360.549229]  free_exit_list+0x101/0x140
[ 1360.549236]  unregister_pernet_operations+0x107/0x160
[ 1360.549245]  unregister_pernet_subsys+0x1c/0x30
[ 1360.549254]  nf_tables_module_exit+0x43/0x80 [nf_tables]
[ 1360.549345]  __do_sys_delete_module+0x253/0x370
[ 1360.549352]  do_syscall_64+0x55/0x120
[ 1360.549360]  entry_SYSCALL_64_after_hwframe+0x55/0x5d

(gdb) list *__nft_release_table+0x473
0x1e033 is in __nft_release_table (net/netfilter/nf_tables_api.c:11354).
11349           list_for_each_entry_safe(flowtable, nf, &table->flowtables, list) {
11350                   list_del(&flowtable->list);
11351                   nft_use_dec(&table->use);
11352                   nf_tables_flowtable_destroy(flowtable);
11353           }
11354           list_for_each_entry_safe(set, ns, &table->sets, list) {
11355                   list_del(&set->list);
11356                   nft_use_dec(&table->use);
11357                   if (set->flags & (NFT_SET_MAP | NFT_SET_OBJECT))
11358                           nft_map_deactivate(&ctx, set);
(gdb)

[ 1360.549372] Last potentially related work creation:
[ 1360.549376]  kasan_save_stack+0x20/0x40
[ 1360.549384]  __kasan_record_aux_stack+0x9b/0xb0
[ 1360.549392]  __queue_work+0x3fb/0x780
[ 1360.549399]  queue_work_on+0x4f/0x60
[ 1360.549407]  nft_rhash_remove+0x33b/0x340 [nf_tables]
[ 1360.549516]  nf_tables_commit+0x1c6a/0x2620 [nf_tables]
[ 1360.549625]  nfnetlink_rcv_batch+0x728/0xdc0 [nfnetlink]
[ 1360.549647]  nfnetlink_rcv+0x1a8/0x1e0 [nfnetlink]
[ 1360.549671]  netlink_unicast+0x367/0x4f0
[ 1360.549680]  netlink_sendmsg+0x34b/0x610
[ 1360.549690]  ____sys_sendmsg+0x4d4/0x510
[ 1360.549697]  ___sys_sendmsg+0xc9/0x120
[ 1360.549706]  __sys_sendmsg+0xbe/0x140
[ 1360.549715]  do_syscall_64+0x55/0x120
[ 1360.549725]  entry_SYSCALL_64_after_hwframe+0x55/0x5d

Fixes: 0935d55884 ("netfilter: nf_tables: asynchronous release")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-10 16:28:25 +02:00
Pablo Neira Ayuso
745cf6a843 netfilter: nf_tables: reject new basechain after table flag update
commit 994209ddf4 upstream.

When dormant flag is toggled, hooks are disabled in the commit phase by
iterating over current chains in table (existing and new).

The following configuration allows for an inconsistent state:

  add table x
  add chain x y { type filter hook input priority 0; }
  add table x { flags dormant; }
  add chain x w { type filter hook input priority 1; }

which triggers the following warning when trying to unregister chain w
which is already unregistered.

[  127.322252] WARNING: CPU: 7 PID: 1211 at net/netfilter/core.c:50                                                                     1 __nf_unregister_net_hook+0x21a/0x260
[...]
[  127.322519] Call Trace:
[  127.322521]  <TASK>
[  127.322524]  ? __warn+0x9f/0x1a0
[  127.322531]  ? __nf_unregister_net_hook+0x21a/0x260
[  127.322537]  ? report_bug+0x1b1/0x1e0
[  127.322545]  ? handle_bug+0x3c/0x70
[  127.322552]  ? exc_invalid_op+0x17/0x40
[  127.322556]  ? asm_exc_invalid_op+0x1a/0x20
[  127.322563]  ? kasan_save_free_info+0x3b/0x60
[  127.322570]  ? __nf_unregister_net_hook+0x6a/0x260
[  127.322577]  ? __nf_unregister_net_hook+0x21a/0x260
[  127.322583]  ? __nf_unregister_net_hook+0x6a/0x260
[  127.322590]  ? __nf_tables_unregister_hook+0x8a/0xe0 [nf_tables]
[  127.322655]  nft_table_disable+0x75/0xf0 [nf_tables]
[  127.322717]  nf_tables_commit+0x2571/0x2620 [nf_tables]

Fixes: 179d9ba555 ("netfilter: nf_tables: fix table flag updates")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-10 16:28:25 +02:00
Pablo Neira Ayuso
73e4f955b3 netfilter: nf_tables: reject constant set with timeout
commit 5f4fc4bd5c upstream.

This set combination is weird: it allows for elements to be
added/deleted, but once bound to the rule it cannot be updated anymore.
Eventually, all elements expire, leading to an empty set which cannot
be updated anymore. Reject this flags combination.

Cc: stable@vger.kernel.org
Fixes: 761da2935d ("netfilter: nf_tables: add set timeout API support")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-03 15:19:40 +02:00
Pablo Neira Ayuso
72c1efe3f2 netfilter: nf_tables: disallow anonymous set with timeout flag
commit 16603605b6 upstream.

Anonymous sets are never used with timeout from userspace, reject this.
Exception to this rule is NFT_SET_EVAL to ensure legacy meters still work.

Cc: stable@vger.kernel.org
Fixes: 761da2935d ("netfilter: nf_tables: add set timeout API support")
Reported-by: lonial con <kongln9170@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-03 15:19:40 +02:00
Pablo Neira Ayuso
406b0241d0 netfilter: nf_tables: mark set as dead when unbinding anonymous set with timeout
commit 552705a365 upstream.

While the rhashtable set gc runs asynchronously, a race allows it to
collect elements from anonymous sets with timeouts while it is being
released from the commit path.

Mingi Cho originally reported this issue in a different path in 6.1.x
with a pipapo set with low timeouts which is not possible upstream since
7395dfacff ("netfilter: nf_tables: use timestamp to check for set
element timeout").

Fix this by setting on the dead flag for anonymous sets to skip async gc
in this case.

According to 08e4c8c591 ("netfilter: nf_tables: mark newset as dead on
transaction abort"), Florian plans to accelerate abort path by releasing
objects via workqueue, therefore, this sets on the dead flag for abort
path too.

Cc: stable@vger.kernel.org
Fixes: 5f68718b34 ("netfilter: nf_tables: GC transaction API to avoid race with control plane")
Reported-by: Mingi Cho <mgcho.minic@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-03 15:19:39 +02:00
Pablo Neira Ayuso
9683cb6c2c netfilter: nf_tables: do not compare internal table flags on updates
[ Upstream commit 4a0e7f2dec ]

Restore skipping transaction if table update does not modify flags.

Fixes: 179d9ba555 ("netfilter: nf_tables: fix table flag updates")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-26 18:21:02 -04:00
Pablo Neira Ayuso
5ad233dc73 netfilter: nft_set_pipapo: release elements in clone only from destroy path
[ Upstream commit b0e256f3dd ]

Clone already always provides a current view of the lookup table, use it
to destroy the set, otherwise it is possible to destroy elements twice.

This fix requires:

 212ed75dc5 ("netfilter: nf_tables: integrate pipapo into commit protocol")

which came after:

 9827a0e6e2 ("netfilter: nft_set_pipapo: release elements in clone from abort path").

Fixes: 9827a0e6e2 ("netfilter: nft_set_pipapo: release elements in clone from abort path")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-26 18:21:01 -04:00
Lena Wang
39001e3c42 netfilter: nf_conntrack_h323: Add protection for bmp length out of range
[ Upstream commit 767146637e ]

UBSAN load reports an exception of BRK#5515 SHIFT_ISSUE:Bitwise shifts
that are out of bounds for their data type.

vmlinux   get_bitmap(b=75) + 712
<net/netfilter/nf_conntrack_h323_asn1.c:0>
vmlinux   decode_seq(bs=0xFFFFFFD008037000, f=0xFFFFFFD008037018, level=134443100) + 1956
<net/netfilter/nf_conntrack_h323_asn1.c:592>
vmlinux   decode_choice(base=0xFFFFFFD0080370F0, level=23843636) + 1216
<net/netfilter/nf_conntrack_h323_asn1.c:814>
vmlinux   decode_seq(f=0xFFFFFFD0080371A8, level=134443500) + 812
<net/netfilter/nf_conntrack_h323_asn1.c:576>
vmlinux   decode_choice(base=0xFFFFFFD008037280, level=0) + 1216
<net/netfilter/nf_conntrack_h323_asn1.c:814>
vmlinux   DecodeRasMessage() + 304
<net/netfilter/nf_conntrack_h323_asn1.c:833>
vmlinux   ras_help() + 684
<net/netfilter/nf_conntrack_h323_main.c:1728>
vmlinux   nf_confirm() + 188
<net/netfilter/nf_conntrack_proto.c:137>

Due to abnormal data in skb->data, the extension bitmap length
exceeds 32 when decoding ras message then uses the length to make
a shift operation. It will change into negative after several loop.
UBSAN load could detect a negative shift as an undefined behaviour
and reports exception.
So we add the protection to avoid the length exceeding 32. Or else
it will return out of range error and stop decoding.

Fixes: 5e35941d99 ("[NETFILTER]: Add H.323 conntrack/NAT helper")
Signed-off-by: Lena Wang <lena.wang@mediatek.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-15 10:48:16 -04:00
Florian Westphal
bce83144ba netfilter: nft_ct: fix l3num expectations with inet pseudo family
[ Upstream commit 9999378996 ]

Following is rejected but should be allowed:

table inet t {
        ct expectation exp1 {
                [..]
                l3proto ip

Valid combos are:
table ip t, l3proto ip
table ip6 t, l3proto ip6
table inet t, l3proto ip OR l3proto ip6

Disallow inet pseudeo family, the l3num must be a on-wire protocol known
to conntrack.

Retain NFPROTO_INET case to make it clear its rejected
intentionally rather as oversight.

Fixes: 8059918a13 ("netfilter: nft_ct: sanitize layer 3 and 4 protocol number in custom expectations")
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>
2024-03-15 10:48:16 -04:00
Florian Westphal
2b1414d5e9 netfilter: bridge: confirm multicast packets before passing them up the stack
[ Upstream commit 62e7151ae3 ]

conntrack nf_confirm logic cannot handle cloned skbs referencing
the same nf_conn entry, which will happen for multicast (broadcast)
frames on bridges.

 Example:
    macvlan0
       |
      br0
     /  \
  ethX    ethY

 ethX (or Y) receives a L2 multicast or broadcast packet containing
 an IP packet, flow is not yet in conntrack table.

 1. skb passes through bridge and fake-ip (br_netfilter)Prerouting.
    -> skb->_nfct now references a unconfirmed entry
 2. skb is broad/mcast packet. bridge now passes clones out on each bridge
    interface.
 3. skb gets passed up the stack.
 4. In macvlan case, macvlan driver retains clone(s) of the mcast skb
    and schedules a work queue to send them out on the lower devices.

    The clone skb->_nfct is not a copy, it is the same entry as the
    original skb.  The macvlan rx handler then returns RX_HANDLER_PASS.
 5. Normal conntrack hooks (in NF_INET_LOCAL_IN) confirm the orig skb.

The Macvlan broadcast worker and normal confirm path will race.

This race will not happen if step 2 already confirmed a clone. In that
case later steps perform skb_clone() with skb->_nfct already confirmed (in
hash table).  This works fine.

But such confirmation won't happen when eb/ip/nftables rules dropped the
packets before they reached the nf_confirm step in postrouting.

Pablo points out that nf_conntrack_bridge doesn't allow use of stateful
nat, so we can safely discard the nf_conn entry and let inet call
conntrack again.

This doesn't work for bridge netfilter: skb could have a nat
transformation. Also bridge nf prevents re-invocation of inet prerouting
via 'sabotage_in' hook.

Work around this problem by explicit confirmation of the entry at LOCAL_IN
time, before upper layer has a chance to clone the unconfirmed entry.

The downside is that this disables NAT and conntrack helpers.

Alternative fix would be to add locking to all code parts that deal with
unconfirmed packets, but even if that could be done in a sane way this
opens up other problems, for example:

-m physdev --physdev-out eth0 -j SNAT --snat-to 1.2.3.4
-m physdev --physdev-out eth1 -j SNAT --snat-to 1.2.3.5

For multicast case, only one of such conflicting mappings will be
created, conntrack only handles 1:1 NAT mappings.

Users should set create a setup that explicitly marks such traffic
NOTRACK (conntrack bypass) to avoid this, but we cannot auto-bypass
them, ruleset might have accept rules for untracked traffic already,
so user-visible behaviour would change.

Suggested-by: Pablo Neira Ayuso <pablo@netfilter.org>
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=217777
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>
2024-03-06 14:45:08 +00:00
Florian Westphal
b8afc22a11 netfilter: let reset rules clean out conntrack entries
[ Upstream commit 2954fe60e3 ]

iptables/nftables support responding to tcp packets with tcp resets.

The generated tcp reset packet passes through both output and postrouting
netfilter hooks, but conntrack will never see them because the generated
skb has its ->nfct pointer copied over from the packet that triggered the
reset rule.

If the reset rule is used for established connections, this
may result in the conntrack entry to be around for a very long
time (default timeout is 5 days).

One way to avoid this would be to not copy the nf_conn pointer
so that the rest packet passes through conntrack too.

Problem is that output rules might not have the same conntrack
zone setup as the prerouting ones, so its possible that the
reset skb won't find the correct entry.  Generating a template
entry for the skb seems error prone as well.

Add an explicit "closing" function that switches a confirmed
conntrack entry to closed state and wire this up for tcp.

If the entry isn't confirmed, no action is needed because
the conntrack entry will never be committed to the table.

Reported-by: Russel King <linux@armlinux.org.uk>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Stable-dep-of: 62e7151ae3 ("netfilter: bridge: confirm multicast packets before passing them up the stack")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-06 14:45:08 +00:00
Ignat Korchagin
ddf6ee3df3 netfilter: nf_tables: allow NFPROTO_INET in nft_(match/target)_validate()
[ Upstream commit 7e0f122c65 ]

Commit d0009effa8 ("netfilter: nf_tables: validate NFPROTO_* family") added
some validation of NFPROTO_* families in the nft_compat module, but it broke
the ability to use legacy iptables modules in dual-stack nftables.

While with legacy iptables one had to independently manage IPv4 and IPv6
tables, with nftables it is possible to have dual-stack tables sharing the
rules. Moreover, it was possible to use rules based on legacy iptables
match/target modules in dual-stack nftables.

As an example, the program from [2] creates an INET dual-stack family table
using an xt_bpf based rule, which looks like the following (the actual output
was generated with a patched nft tool as the current nft tool does not parse
dual stack tables with legacy match rules, so consider it for illustrative
purposes only):

table inet testfw {
  chain input {
    type filter hook prerouting priority filter; policy accept;
    bytecode counter packets 0 bytes 0 accept
  }
}

After d0009effa8 ("netfilter: nf_tables: validate NFPROTO_* family") we get
EOPNOTSUPP for the above program.

Fix this by allowing NFPROTO_INET for nft_(match/target)_validate(), but also
restrict the functions to classic iptables hooks.

Changes in v3:
  * clarify that upstream nft will not display such configuration properly and
    that the output was generated with a patched nft tool
  * remove example program from commit description and link to it instead
  * no code changes otherwise

Changes in v2:
  * restrict nft_(match/target)_validate() to classic iptables hooks
  * rewrite example program to use unmodified libnftnl

Fixes: d0009effa8 ("netfilter: nf_tables: validate NFPROTO_* family")
Link: https://lore.kernel.org/all/Zc1PfoWN38UuFJRI@calendula/T/#mc947262582c90fec044c7a3398cc92fac7afea72 [1]
Link: https://lore.kernel.org/all/20240220145509.53357-1-ignat@cloudflare.com/ [2]
Reported-by: Jordan Griege <jgriege@cloudflare.com>
Signed-off-by: Ignat Korchagin <ignat@cloudflare.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-06 14:45:08 +00:00
Pablo Neira Ayuso
b7be6c737a netfilter: nf_tables: disallow timeout for anonymous sets
commit e26d3009ef upstream.

Never used from userspace, disallow these parameters.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-06 14:45:04 +00:00
Florian Westphal
ea33b81669 netfilter: nf_tables: use kzalloc for hook allocation
[ Upstream commit 195e5f88c2 ]

KMSAN reports unitialized variable when registering the hook,
   reg->hook_ops_type == NF_HOOK_OP_BPF)
        ~~~~~~~~~~~ undefined

This is a small structure, just use kzalloc to make sure this
won't happen again when new fields get added to nf_hook_ops.

Fixes: 7b4b2fa375 ("netfilter: annotate nf_tables base hook ops")
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>
2024-03-01 13:26:38 +01:00
Pablo Neira Ayuso
f305359186 netfilter: nf_tables: register hooks last when adding new chain/flowtable
[ Upstream commit d472e9853d ]

Register hooks last when adding chain/flowtable to ensure that packets do
not walk over datastructure that is being released in the error path
without waiting for the rcu grace period.

Fixes: 91c7b38dc9 ("netfilter: nf_tables: use new transaction infrastructure to handle chain")
Fixes: 3b49e2e94e ("netfilter: nf_tables: add flow table netlink frontend")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-01 13:26:38 +01:00
Pablo Neira Ayuso
26994a04b0 netfilter: nf_tables: rename function to destroy hook list
[ Upstream commit cdc3254663 ]

Rename nft_flowtable_hooks_destroy() by nft_hooks_destroy() to prepare
for netdev chain device updates.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Stable-dep-of: d472e9853d ("netfilter: nf_tables: register hooks last when adding new chain/flowtable")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-01 13:26:38 +01:00
Pablo Neira Ayuso
a6cafdb49a netfilter: nft_flow_offload: release dst in case direct xmit path is used
[ Upstream commit 8762785f45 ]

Direct xmit does not use it since it calls dev_queue_xmit() to send
packets, hence it calls dst_release().

kmemleak reports:

unreferenced object 0xffff88814f440900 (size 184):
  comm "softirq", pid 0, jiffies 4294951896
  hex dump (first 32 bytes):
    00 60 5b 04 81 88 ff ff 00 e6 e8 82 ff ff ff ff  .`[.............
    21 0b 50 82 ff ff ff ff 00 00 00 00 00 00 00 00  !.P.............
  backtrace (crc cb2bf5d6):
    [<000000003ee17107>] kmem_cache_alloc+0x286/0x340
    [<0000000021a5de2c>] dst_alloc+0x43/0xb0
    [<00000000f0671159>] rt_dst_alloc+0x2e/0x190
    [<00000000fe5092c9>] __mkroute_output+0x244/0x980
    [<000000005fb96fb0>] ip_route_output_flow+0xc0/0x160
    [<0000000045367433>] nf_ip_route+0xf/0x30
    [<0000000085da1d8e>] nf_route+0x2d/0x60
    [<00000000d1ecd1cb>] nft_flow_route+0x171/0x6a0 [nft_flow_offload]
    [<00000000d9b2fb60>] nft_flow_offload_eval+0x4e8/0x700 [nft_flow_offload]
    [<000000009f447dbb>] expr_call_ops_eval+0x53/0x330 [nf_tables]
    [<00000000072e1be6>] nft_do_chain+0x17c/0x840 [nf_tables]
    [<00000000d0551029>] nft_do_chain_inet+0xa1/0x210 [nf_tables]
    [<0000000097c9d5c6>] nf_hook_slow+0x5b/0x160
    [<0000000005eccab1>] ip_forward+0x8b6/0x9b0
    [<00000000553a269b>] ip_rcv+0x221/0x230
    [<00000000412872e5>] __netif_receive_skb_one_core+0xfe/0x110

Fixes: fa502c8656 ("netfilter: flowtable: simplify route logic")
Reported-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-01 13:26:37 +01:00
Pablo Neira Ayuso
012df10717 netfilter: nft_flow_offload: reset dst in route object after setting up flow
[ Upstream commit 9e0f043038 ]

dst is transferred to the flow object, route object does not own it
anymore.  Reset dst in route object, otherwise if flow_offload_add()
fails, error path releases dst twice, leading to a refcount underflow.

Fixes: a3c90f7a23 ("netfilter: nf_tables: flow offload expression")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-01 13:26:37 +01:00
Pablo Neira Ayuso
9c5662e95a netfilter: flowtable: simplify route logic
[ Upstream commit fa502c8656 ]

Grab reference to dst from skbuff earlier to simplify route caching.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Stable-dep-of: 9e0f043038 ("netfilter: nft_flow_offload: reset dst in route object after setting up flow")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-01 13:26:37 +01:00
Florian Westphal
0c9302a6da netfilter: nf_tables: set dormant flag on hook register failure
[ Upstream commit bccebf6470 ]

We need to set the dormant flag again if we fail to register
the hooks.

During memory pressure hook registration can fail and we end up
with a table marked as active but no registered hooks.

On table/base chain deletion, nf_tables will attempt to unregister
the hook again which yields a warn splat from the nftables core.

Reported-and-tested-by: syzbot+de4025c006ec68ac56fc@syzkaller.appspotmail.com
Fixes: 179d9ba555 ("netfilter: nf_tables: fix table flag updates")
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>
2024-03-01 13:26:37 +01:00
Xin Long
41b256f473 netfilter: conntrack: check SCTP_CID_SHUTDOWN_ACK for vtag setting in sctp_new
[ Upstream commit 6e348067ee ]

The annotation says in sctp_new(): "If it is a shutdown ack OOTB packet, we
expect a return shutdown complete, otherwise an ABORT Sec 8.4 (5) and (8)".
However, it does not check SCTP_CID_SHUTDOWN_ACK before setting vtag[REPLY]
in the conntrack entry(ct).

Because of that, if the ct in Router disappears for some reason in [1]
with the packet sequence like below:

   Client > Server: sctp (1) [INIT] [init tag: 3201533963]
   Server > Client: sctp (1) [INIT ACK] [init tag: 972498433]
   Client > Server: sctp (1) [COOKIE ECHO]
   Server > Client: sctp (1) [COOKIE ACK]
   Client > Server: sctp (1) [DATA] (B)(E) [TSN: 3075057809]
   Server > Client: sctp (1) [SACK] [cum ack 3075057809]
   Server > Client: sctp (1) [HB REQ]
   (the ct in Router disappears somehow)  <-------- [1]
   Client > Server: sctp (1) [HB ACK]
   Client > Server: sctp (1) [DATA] (B)(E) [TSN: 3075057810]
   Client > Server: sctp (1) [DATA] (B)(E) [TSN: 3075057810]
   Client > Server: sctp (1) [HB REQ]
   Client > Server: sctp (1) [DATA] (B)(E) [TSN: 3075057810]
   Client > Server: sctp (1) [HB REQ]
   Client > Server: sctp (1) [ABORT]

when processing HB ACK packet in Router it calls sctp_new() to initialize
the new ct with vtag[REPLY] set to HB_ACK packet's vtag.

Later when sending DATA from Client, all the SACKs from Server will get
dropped in Router, as the SACK packet's vtag does not match vtag[REPLY]
in the ct. The worst thing is the vtag in this ct will never get fixed
by the upcoming packets from Server.

This patch fixes it by checking SCTP_CID_SHUTDOWN_ACK before setting
vtag[REPLY] in the ct in sctp_new() as the annotation says. With this
fix, it will leave vtag[REPLY] in ct to 0 in the case above, and the
next HB REQ/ACK from Server is able to fix the vtag as its value is 0
in nf_conntrack_sctp_packet().

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-01 13:26:27 +01:00
Jozsef Kadlecsik
ebc442c640 netfilter: ipset: Missing gc cancellations fixed
commit 27c5a095e2 upstream.

The patch fdb8e12cc2cc ("netfilter: ipset: fix performance regression
in swap operation") missed to add the calls to gc cancellations
at the error path of create operations and at module unload. Also,
because the half of the destroy operations now executed by a
function registered by call_rcu(), neither NFNL_SUBSYS_IPSET mutex
or rcu read lock is held and therefore the checking of them results
false warnings.

Fixes: 97f7cf1cd8 ("netfilter: ipset: fix performance regression in swap operation")
Reported-by: syzbot+52bbc0ad036f6f0d4a25@syzkaller.appspotmail.com
Reported-by: Brad Spengler <spender@grsecurity.net>
Reported-by: Стас Ничипорович <stasn77@gmail.com>
Tested-by: Brad Spengler <spender@grsecurity.net>
Tested-by: Стас Ничипорович <stasn77@gmail.com>
Signed-off-by: Jozsef Kadlecsik <kadlec@netfilter.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-23 09:12:50 +01:00
Jozsef Kadlecsik
653bc5e6d9 netfilter: ipset: fix performance regression in swap operation
commit 97f7cf1cd8 upstream.

The patch "netfilter: ipset: fix race condition between swap/destroy
and kernel side add/del/test", commit 28628fa9 fixes a race condition.
But the synchronize_rcu() added to the swap function unnecessarily slows
it down: it can safely be moved to destroy and use call_rcu() instead.

Eric Dumazet pointed out that simply calling the destroy functions as
rcu callback does not work: sets with timeout use garbage collectors
which need cancelling at destroy which can wait. Therefore the destroy
functions are split into two: cancelling garbage collectors safely at
executing the command received by netlink and moving the remaining
part only into the rcu callback.

Link: https://lore.kernel.org/lkml/C0829B10-EAA6-4809-874E-E1E9C05A8D84@automattic.com/
Fixes: 28628fa952 ("netfilter: ipset: fix race condition between swap/destroy and kernel side add/del/test")
Reported-by: Ale Crismani <ale.crismani@automattic.com>
Reported-by: David Wang <00107082@163.com>
Tested-by: David Wang <00107082@163.com>
Signed-off-by: Jozsef Kadlecsik <kadlec@netfilter.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-23 09:12:49 +01:00
Linus Torvalds
f70efe54b9 work around gcc bugs with 'asm goto' with outputs
commit 68fb3ca0e4 upstream.

We've had issues with gcc and 'asm goto' before, and we created a
'asm_volatile_goto()' macro for that in the past: see commits
3f0116c323 ("compiler/gcc4: Add quirk for 'asm goto' miscompilation
bug") and a9f180345f ("compiler/gcc4: Make quirk for
asm_volatile_goto() unconditional").

Then, much later, we ended up removing the workaround in commit
43c249ea0b ("compiler-gcc.h: remove ancient workaround for gcc PR
58670") because we no longer supported building the kernel with the
affected gcc versions, but we left the macro uses around.

Now, Sean Christopherson reports a new version of a very similar
problem, which is fixed by re-applying that ancient workaround.  But the
problem in question is limited to only the 'asm goto with outputs'
cases, so instead of re-introducing the old workaround as-is, let's
rename and limit the workaround to just that much less common case.

It looks like there are at least two separate issues that all hit in
this area:

 (a) some versions of gcc don't mark the asm goto as 'volatile' when it
     has outputs:

        https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98619
        https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110420

     which is easy to work around by just adding the 'volatile' by hand.

 (b) Internal compiler errors:

        https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110422

     which are worked around by adding the extra empty 'asm' as a
     barrier, as in the original workaround.

but the problem Sean sees may be a third thing since it involves bad
code generation (not an ICE) even with the manually added 'volatile'.

The same old workaround works for this case, even if this feels a
bit like voodoo programming and may only be hiding the issue.

Reported-and-tested-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/all/20240208220604.140859-1-seanjc@google.com/
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Uros Bizjak <ubizjak@gmail.com>
Cc: Jakub Jelinek <jakub@redhat.com>
Cc: Andrew Pinski <quic_apinski@quicinc.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-23 09:12:28 +01:00
Pablo Neira Ayuso
1296c110c5 netfilter: nft_set_rbtree: skip end interval element from gc
commit 60c0c230c6 upstream.

rbtree lazy gc on insert might collect an end interval element that has
been just added in this transactions, skip end interval elements that
are not yet active.

Fixes: f718863aca ("netfilter: nft_set_rbtree: fix overlap expiration walk")
Cc: stable@vger.kernel.org
Reported-by: lonial con <kongln9170@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-16 19:06:32 +01:00
Florian Westphal
a442ff5405 netfilter: nft_set_pipapo: remove scratch_aligned pointer
[ Upstream commit 5a8cdf6fd8 ]

use ->scratch for both avx2 and the generic implementation.

After previous change the scratch->map member is always aligned properly
for AVX2, so we can just use scratch->map in AVX2 too.

The alignoff delta is stored in the scratchpad so we can reconstruct
the correct address to free the area again.

Fixes: 7400b06396 ("nft_set_pipapo: Introduce AVX2-based lookup implementation")
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
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>
2024-02-16 19:06:28 +01:00
Florian Westphal
fac3478d5b netfilter: nft_set_pipapo: add helper to release pcpu scratch area
[ Upstream commit 47b1c03c3c ]

After next patch simple kfree() is not enough anymore, so add
a helper for it.

Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Stable-dep-of: 5a8cdf6fd8 ("netfilter: nft_set_pipapo: remove scratch_aligned pointer")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-02-16 19:06:28 +01:00
Florian Westphal
3eaab7d565 netfilter: nft_set_pipapo: store index in scratch maps
[ Upstream commit 76313d1a4a ]

Pipapo needs a scratchpad area to keep state during matching.
This state can be large and thus cannot reside on stack.

Each set preallocates percpu areas for this.

On each match stage, one scratchpad half starts with all-zero and the other
is inited to all-ones.

At the end of each stage, the half that starts with all-ones is
always zero.  Before next field is tested, pointers to the two halves
are swapped, i.e.  resmap pointer turns into fill pointer and vice versa.

After the last field has been processed, pipapo stashes the
index toggle in a percpu variable, with assumption that next packet
will start with the all-zero half and sets all bits in the other to 1.

This isn't reliable.

There can be multiple sets and we can't be sure that the upper
and lower half of all set scratch map is always in sync (lookups
can be conditional), so one set might have swapped, but other might
not have been queried.

Thus we need to keep the index per-set-and-cpu, just like the
scratchpad.

Note that this bug fix is incomplete, there is a related issue.

avx2 and normal implementation might use slightly different areas of the
map array space due to the avx2 alignment requirements, so
m->scratch (generic/fallback implementation) and ->scratch_aligned
(avx) may partially overlap. scratch and scratch_aligned are not distinct
objects, the latter is just the aligned address of the former.

After this change, write to scratch_align->map_index may write to
scratch->map, so this issue becomes more prominent, we can set to 1
a bit in the supposedly-all-zero area of scratch->map[].

A followup patch will remove the scratch_aligned and makes generic and
avx code use the same (aligned) area.

Its done in a separate change to ease review.

Fixes: 3c4287f620 ("nf_tables: Add set type for arbitrary concatenation of ranges")
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
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>
2024-02-16 19:06:28 +01:00
Pablo Neira Ayuso
181dade251 netfilter: nft_ct: reject direction for ct id
[ Upstream commit 38ed1c7062 ]

Direction attribute is ignored, reject it in case this ever needs to be
supported

Fixes: 3087c3f7c2 ("netfilter: nft_ct: Add ct id support")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-02-16 19:06:28 +01:00
Pablo Neira Ayuso
a060da3235 netfilter: nft_compat: restrict match/target protocol to u16
[ Upstream commit d694b75489 ]

xt_check_{match,target} expects u16, but NFTA_RULE_COMPAT_PROTO is u32.

NLA_POLICY_MAX(NLA_BE32, 65535) cannot be used because .max in
nla_policy is s16, see 3e48be05f3 ("netlink: add attribute range
validation to policy").

Fixes: 0ca743a559 ("netfilter: nf_tables: add compatibility layer for x_tables")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-02-16 19:06:28 +01:00
Pablo Neira Ayuso
8762bcc927 netfilter: nft_compat: reject unused compat flag
[ Upstream commit 292781c3c5 ]

Flag (1 << 0) is ignored is set, never used, reject it it with EINVAL
instead.

Fixes: 0ca743a559 ("netfilter: nf_tables: add compatibility layer for x_tables")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-02-16 19:06:28 +01:00
Pablo Neira Ayuso
e79ef7966e netfilter: nft_compat: narrow down revision to unsigned 8-bits
[ Upstream commit 36fa8d6971 ]

xt_find_revision() expects u8, restrict it to this datatype.

Fixes: 0ca743a559 ("netfilter: nf_tables: add compatibility layer for x_tables")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-02-16 19:06:27 +01:00
Pablo Neira Ayuso
0f501dae16 netfilter: nft_ct: sanitize layer 3 and 4 protocol number in custom expectations
[ Upstream commit 8059918a13 ]

- Disallow families other than NFPROTO_{IPV4,IPV6,INET}.
- Disallow layer 4 protocol with no ports, since destination port is a
  mandatory attribute for this object.

Fixes: 857b46027d ("netfilter: nft_ct: add ct expectations support")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-02-05 20:13:02 +00:00
Pablo Neira Ayuso
9ff981cd65 netfilter: nf_log: replace BUG_ON by WARN_ON_ONCE when putting logger
[ Upstream commit 259eb32971 ]

Module reference is bumped for each user, this should not ever happen.

But BUG_ON check should use rcu_access_pointer() instead.

If this ever happens, do WARN_ON_ONCE() instead of BUG_ON() and
consolidate pointer check under the rcu read side lock section.

Fixes: fab4085f4e ("netfilter: log: nf_log_packet() as real unified interface")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-02-05 20:13:02 +00:00
Pablo Neira Ayuso
67f0ca0a4c netfilter: nf_tables: restrict tunnel object to NFPROTO_NETDEV
[ Upstream commit 776d451648 ]

Bail out on using the tunnel dst template from other than netdev family.
Add the infrastructure to check for the family in objects.

Fixes: af308b94a2 ("netfilter: nf_tables: add tunnel support")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-02-05 20:13:01 +00:00
Ryan Schaefer
8a51dbf7b7 netfilter: conntrack: correct window scaling with retransmitted SYN
[ Upstream commit fb366fc754 ]

commit c7aab4f170 ("netfilter: nf_conntrack_tcp: re-init for syn packets
only") introduces a bug where SYNs in ORIGINAL direction on reused 5-tuple
result in incorrect window scale negotiation. This commit merged the SYN
re-initialization and simultaneous open or SYN retransmits cases. Merging
this block added the logic in tcp_init_sender() that performed window scale
negotiation to the retransmitted syn case. Previously. this would only
result in updating the sender's scale and flags. After the merge the
additional logic results in improperly clearing the scale in ORIGINAL
direction before any packets in the REPLY direction are received. This
results in packets incorrectly being marked invalid for being
out-of-window.

This can be reproduced with the following trace:

Packet Sequence:
> Flags [S], seq 1687765604, win 62727, options [.. wscale 7], length 0
> Flags [S], seq 1944817196, win 62727, options [.. wscale 7], length 0

In order to fix the issue, only evaluate window negotiation for packets
in the REPLY direction. This was tested with simultaneous open, fast
open, and the above reproduction.

Fixes: c7aab4f170 ("netfilter: nf_conntrack_tcp: re-init for syn packets only")
Signed-off-by: Ryan Schaefer <ryanschf@amazon.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-02-05 20:13:01 +00:00
Florian Westphal
8e34430e33 netfilter: nf_tables: reject QUEUE/DROP verdict parameters
commit f342de4e2f upstream.

This reverts commit e0abdadcc6.

core.c:nf_hook_slow assumes that the upper 16 bits of NF_DROP
verdicts contain a valid errno, i.e. -EPERM, -EHOSTUNREACH or similar,
or 0.

Due to the reverted commit, its possible to provide a positive
value, e.g. NF_ACCEPT (1), which results in use-after-free.

Its not clear to me why this commit was made.

NF_QUEUE is not used by nftables; "queue" rules in nftables
will result in use of "nft_queue" expression.

If we later need to allow specifiying errno values from userspace
(do not know why), this has to call NF_DROP_GETERR and check that
"err <= 0" holds true.

Fixes: e0abdadcc6 ("netfilter: nf_tables: accept QUEUE/DROP verdict parameters")
Cc: stable@vger.kernel.org
Reported-by: Notselwyn <notselwyn@pwning.tech>
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>
2024-01-31 16:17:07 -08:00
Pablo Neira Ayuso
af149a4689 netfilter: nft_chain_filter: handle NETDEV_UNREGISTER for inet/ingress basechain
commit 01acb2e866 upstream.

Remove netdevice from inet/ingress basechain in case NETDEV_UNREGISTER
event is reported, otherwise a stale reference to netdevice remains in
the hook list.

Fixes: 60a3815da7 ("netfilter: add inet ingress support")
Cc: stable@vger.kernel.org
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-31 16:17:07 -08:00
Pablo Neira Ayuso
67ee37360d netfilter: nf_tables: validate NFPROTO_* family
[ Upstream commit d0009effa8 ]

Several expressions explicitly refer to NF_INET_* hook definitions
from expr->ops->validate, however, family is not validated.

Bail out with EOPNOTSUPP in case they are used from unsupported
families.

Fixes: 0ca743a559 ("netfilter: nf_tables: add compatibility layer for x_tables")
Fixes: a3c90f7a23 ("netfilter: nf_tables: flow offload expression")
Fixes: 2fa841938c ("netfilter: nf_tables: introduce routing expression")
Fixes: 554ced0a6e ("netfilter: nf_tables: add support for native socket matching")
Fixes: ad49d86e07 ("netfilter: nf_tables: Add synproxy support")
Fixes: 4ed8eb6570 ("netfilter: nf_tables: Add native tproxy support")
Fixes: 6c47260250 ("netfilter: nf_tables: add xfrm expression")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-31 16:17:06 -08:00
Florian Westphal
ed5b62bbd4 netfilter: nf_tables: restrict anonymous set and map names to 16 bytes
[ Upstream commit b462579b2b ]

nftables has two types of sets/maps, one where userspace defines the
name, and anonymous sets/maps, where userspace defines a template name.

For the latter, kernel requires presence of exactly one "%d".
nftables uses "__set%d" and "__map%d" for this.  The kernel will
expand the format specifier and replaces it with the smallest unused
number.

As-is, userspace could define a template name that allows to move
the set name past the 256 bytes upperlimit (post-expansion).

I don't see how this could be a problem, but I would prefer if userspace
cannot do this, so add a limit of 16 bytes for the '%d' template name.

16 bytes is the old total upper limit for set names that existed when
nf_tables was merged initially.

Fixes: 387454901b ("netfilter: nf_tables: Allow set names of up to 255 chars")
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>
2024-01-31 16:17:06 -08:00
Florian Westphal
bc6e242bb7 netfilter: nft_limit: reject configurations that cause integer overflow
[ Upstream commit c9d9eb9c53 ]

Reject bogus configs where internal token counter wraps around.
This only occurs with very very large requests, such as 17gbyte/s.

Its better to reject this rather than having incorrect ratelimit.

Fixes: d2168e849e ("netfilter: nft_limit: add per-byte limiting")
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>
2024-01-31 16:17:05 -08:00
Fedor Pchelkin
50ee63b800 ipvs: avoid stat macros calls from preemptible context
[ Upstream commit d6938c1c76 ]

Inside decrement_ttl() upon discovering that the packet ttl has exceeded,
__IP_INC_STATS and __IP6_INC_STATS macros can be called from preemptible
context having the following backtrace:

check_preemption_disabled: 48 callbacks suppressed
BUG: using __this_cpu_add() in preemptible [00000000] code: curl/1177
caller is decrement_ttl+0x217/0x830
CPU: 5 PID: 1177 Comm: curl Not tainted 6.7.0+ #34
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0xbd/0xe0
 check_preemption_disabled+0xd1/0xe0
 decrement_ttl+0x217/0x830
 __ip_vs_get_out_rt+0x4e0/0x1ef0
 ip_vs_nat_xmit+0x205/0xcd0
 ip_vs_in_hook+0x9b1/0x26a0
 nf_hook_slow+0xc2/0x210
 nf_hook+0x1fb/0x770
 __ip_local_out+0x33b/0x640
 ip_local_out+0x2a/0x490
 __ip_queue_xmit+0x990/0x1d10
 __tcp_transmit_skb+0x288b/0x3d10
 tcp_connect+0x3466/0x5180
 tcp_v4_connect+0x1535/0x1bb0
 __inet_stream_connect+0x40d/0x1040
 inet_stream_connect+0x57/0xa0
 __sys_connect_file+0x162/0x1a0
 __sys_connect+0x137/0x160
 __x64_sys_connect+0x72/0xb0
 do_syscall_64+0x6f/0x140
 entry_SYSCALL_64_after_hwframe+0x6e/0x76
RIP: 0033:0x7fe6dbbc34e0

Use the corresponding preemption-aware variants: IP_INC_STATS and
IP6_INC_STATS.

Found by Linux Verification Center (linuxtesting.org).

Fixes: 8d8e20e2d7 ("ipvs: Decrement ttl")
Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru>
Acked-by: Julian Anastasov <ja@ssi.bg>
Acked-by: Simon Horman <horms@kernel.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-25 15:27:51 -08:00
Pablo Neira Ayuso
4a45e7e7d2 netfilter: nf_tables: reject NFT_SET_CONCAT with not field length description
[ Upstream commit 113661e074 ]

It is still possible to set on the NFT_SET_CONCAT flag by specifying a
set size and no field description, report EINVAL in such case.

Fixes: 1b6345d416 ("netfilter: nf_tables: check NFT_SET_CONCAT flag if field_count is specified")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-25 15:27:51 -08:00
Pablo Neira Ayuso
b56bce52f9 netfilter: nf_tables: skip dead set elements in netlink dump
[ Upstream commit 6b1ca88e4b ]

Delete from packet path relies on the garbage collector to purge
elements with NFT_SET_ELEM_DEAD_BIT on.

Skip these dead elements from nf_tables_dump_setelem() path, I very
rarely see tests/shell/testcases/maps/typeof_maps_add_delete reports
[DUMP FAILED] showing a mismatch in the expected output with an element
that should not be there.

If the netlink dump happens before GC worker run, it might show dead
elements in the ruleset listing.

nft_rhash_get() already skips dead elements in nft_rhash_cmp(),
therefore, it already does not show the element when getting a single
element via netlink control plane.

Fixes: 5f68718b34 ("netfilter: nf_tables: GC transaction API to avoid race with control plane")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-25 15:27:51 -08:00
Pablo Neira Ayuso
9cb084df01 netfilter: nf_tables: do not allow mismatch field size and set key length
[ Upstream commit 3ce67e3793 ]

The set description provides the size of each field in the set whose sum
should not mismatch the set key length, bail out otherwise.

I did not manage to crash nft_set_pipapo with mismatch fields and set key
length so far, but this is UB which must be disallowed.

Fixes: f3a2181e16 ("netfilter: nf_tables: Support for sets with multiple ranged fields")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-25 15:27:51 -08:00
Pavel Tikhomirov
754ca18ed3 netfilter: propagate net to nf_bridge_get_physindev
[ Upstream commit a54e721970 ]

This is a preparation patch for replacing physindev with physinif on
nf_bridge_info structure. We will use dev_get_by_index_rcu to resolve
device, when needed, and it requires net to be available.

Signed-off-by: Pavel Tikhomirov <ptikhomirov@virtuozzo.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Stable-dep-of: 9874808878 ("netfilter: bridge: replace physindev with physinif in nf_bridge_info")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-25 15:27:51 -08:00
Pavel Tikhomirov
3f1f505277 netfilter: nf_queue: remove excess nf_bridge variable
[ Upstream commit aeaa44075f ]

We don't really need nf_bridge variable here. And nf_bridge_info_exists
is better replacement for nf_bridge_info_get in case we are only
checking for existence.

Signed-off-by: Pavel Tikhomirov <ptikhomirov@virtuozzo.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Stable-dep-of: 9874808878 ("netfilter: bridge: replace physindev with physinif in nf_bridge_info")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-25 15:27:50 -08:00
Pavel Tikhomirov
52d01a40b7 netfilter: nfnetlink_log: use proper helper for fetching physinif
[ Upstream commit c3f9fd54cd ]

We don't use physindev in __build_packet_message except for getting
physinif from it. So let's switch to nf_bridge_get_physinif to get what
we want directly.

Signed-off-by: Pavel Tikhomirov <ptikhomirov@virtuozzo.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Stable-dep-of: 9874808878 ("netfilter: bridge: replace physindev with physinif in nf_bridge_info")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-25 15:27:50 -08:00
Pablo Neira Ayuso
dfa01315c3 netfilter: nft_limit: do not ignore unsupported flags
[ Upstream commit 91a139cee1 ]

Bail out if userspace provides unsupported flags, otherwise future
extensions to the limit expression will be silently ignored by the
kernel.

Fixes: c7862a5f0d ("netfilter: nft_limit: allow to invert matching criteria")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-25 15:27:50 -08:00