Commit Graph

861 Commits

Author SHA1 Message Date
Pablo Neira Ayuso 86a1471d7c netfilter: nf_tables: fix memleak in map from abort path
The delete set command does not rely on the transaction object for
element removal, therefore, a combination of delete element + delete set
from the abort path could result in restoring twice the refcount of the
mapping.

Check for inactive element in the next generation for the delete element
command in the abort path, skip restoring state if next generation bit
has been already cleared. This is similar to the activate logic using
the set walk iterator.

[ 6170.286929] ------------[ cut here ]------------
[ 6170.286939] WARNING: CPU: 6 PID: 790302 at net/netfilter/nf_tables_api.c:2086 nf_tables_chain_destroy+0x1f7/0x220 [nf_tables]
[ 6170.287071] Modules linked in: [...]
[ 6170.287633] CPU: 6 PID: 790302 Comm: kworker/6:2 Not tainted 6.9.0-rc3+ #365
[ 6170.287768] RIP: 0010:nf_tables_chain_destroy+0x1f7/0x220 [nf_tables]
[ 6170.287886] Code: df 48 8d 7d 58 e8 69 2e 3b df 48 8b 7d 58 e8 80 1b 37 df 48 8d 7d 68 e8 57 2e 3b df 48 8b 7d 68 e8 6e 1b 37 df 48 89 ef eb c4 <0f> 0b 48 83 c4 08 5b 5d 41 5c 41 5d 41 5e 41 5f c3 cc cc cc cc 0f
[ 6170.287895] RSP: 0018:ffff888134b8fd08 EFLAGS: 00010202
[ 6170.287904] RAX: 0000000000000001 RBX: ffff888125bffb28 RCX: dffffc0000000000
[ 6170.287912] RDX: 0000000000000003 RSI: ffffffffa20298ab RDI: ffff88811ebe4750
[ 6170.287919] RBP: ffff88811ebe4700 R08: ffff88838e812650 R09: fffffbfff0623a55
[ 6170.287926] R10: ffffffff8311d2af R11: 0000000000000001 R12: ffff888125bffb10
[ 6170.287933] R13: ffff888125bffb10 R14: dead000000000122 R15: dead000000000100
[ 6170.287940] FS:  0000000000000000(0000) GS:ffff888390b00000(0000) knlGS:0000000000000000
[ 6170.287948] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 6170.287955] CR2: 00007fd31fc00710 CR3: 0000000133f60004 CR4: 00000000001706f0
[ 6170.287962] Call Trace:
[ 6170.287967]  <TASK>
[ 6170.287973]  ? __warn+0x9f/0x1a0
[ 6170.287986]  ? nf_tables_chain_destroy+0x1f7/0x220 [nf_tables]
[ 6170.288092]  ? report_bug+0x1b1/0x1e0
[ 6170.287986]  ? nf_tables_chain_destroy+0x1f7/0x220 [nf_tables]
[ 6170.288092]  ? report_bug+0x1b1/0x1e0
[ 6170.288104]  ? handle_bug+0x3c/0x70
[ 6170.288112]  ? exc_invalid_op+0x17/0x40
[ 6170.288120]  ? asm_exc_invalid_op+0x1a/0x20
[ 6170.288132]  ? nf_tables_chain_destroy+0x2b/0x220 [nf_tables]
[ 6170.288243]  ? nf_tables_chain_destroy+0x1f7/0x220 [nf_tables]
[ 6170.288366]  ? nf_tables_chain_destroy+0x2b/0x220 [nf_tables]
[ 6170.288483]  nf_tables_trans_destroy_work+0x588/0x590 [nf_tables]

Fixes: 591054469b ("netfilter: nf_tables: revisit chain/object refcounting from elements")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-04-18 02:41:32 +02:00
Pablo Neira Ayuso e79b47a861 netfilter: nf_tables: restore set elements when delete set fails
From abort path, nft_mapelem_activate() needs to restore refcounters to
the original state. Currently, it uses the set->ops->walk() to iterate
over these set elements. The existing set iterator skips inactive
elements in the next generation, this does not work from the abort path
to restore the original state since it has to skip active elements
instead (not inactive ones).

This patch moves the check for inactive elements to the set iterator
callback, then it reverses the logic for the .activate case which
needs to skip active elements.

Toggle next generation bit for elements when delete set command is
invoked and call nft_clear() from .activate (abort) path to restore the
next generation bit.

The splat below shows an object in mappings memleak:

[43929.457523] ------------[ cut here ]------------
[43929.457532] WARNING: CPU: 0 PID: 1139 at include/net/netfilter/nf_tables.h:1237 nft_setelem_data_deactivate+0xe4/0xf0 [nf_tables]
[...]
[43929.458014] RIP: 0010:nft_setelem_data_deactivate+0xe4/0xf0 [nf_tables]
[43929.458076] Code: 83 f8 01 77 ab 49 8d 7c 24 08 e8 37 5e d0 de 49 8b 6c 24 08 48 8d 7d 50 e8 e9 5c d0 de 8b 45 50 8d 50 ff 89 55 50 85 c0 75 86 <0f> 0b eb 82 0f 0b eb b3 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90
[43929.458081] RSP: 0018:ffff888140f9f4b0 EFLAGS: 00010246
[43929.458086] RAX: 0000000000000000 RBX: ffff8881434f5288 RCX: dffffc0000000000
[43929.458090] RDX: 00000000ffffffff RSI: ffffffffa26d28a7 RDI: ffff88810ecc9550
[43929.458093] RBP: ffff88810ecc9500 R08: 0000000000000001 R09: ffffed10281f3e8f
[43929.458096] R10: 0000000000000003 R11: ffff0000ffff0000 R12: ffff8881434f52a0
[43929.458100] R13: ffff888140f9f5f4 R14: ffff888151c7a800 R15: 0000000000000002
[43929.458103] FS:  00007f0c687c4740(0000) GS:ffff888390800000(0000) knlGS:0000000000000000
[43929.458107] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[43929.458111] CR2: 00007f58dbe5b008 CR3: 0000000123602005 CR4: 00000000001706f0
[43929.458114] Call Trace:
[43929.458118]  <TASK>
[43929.458121]  ? __warn+0x9f/0x1a0
[43929.458127]  ? nft_setelem_data_deactivate+0xe4/0xf0 [nf_tables]
[43929.458188]  ? report_bug+0x1b1/0x1e0
[43929.458196]  ? handle_bug+0x3c/0x70
[43929.458200]  ? exc_invalid_op+0x17/0x40
[43929.458211]  ? nft_setelem_data_deactivate+0xd7/0xf0 [nf_tables]
[43929.458271]  ? nft_setelem_data_deactivate+0xe4/0xf0 [nf_tables]
[43929.458332]  nft_mapelem_deactivate+0x24/0x30 [nf_tables]
[43929.458392]  nft_rhash_walk+0xdd/0x180 [nf_tables]
[43929.458453]  ? __pfx_nft_rhash_walk+0x10/0x10 [nf_tables]
[43929.458512]  ? rb_insert_color+0x2e/0x280
[43929.458520]  nft_map_deactivate+0xdc/0x1e0 [nf_tables]
[43929.458582]  ? __pfx_nft_map_deactivate+0x10/0x10 [nf_tables]
[43929.458642]  ? __pfx_nft_mapelem_deactivate+0x10/0x10 [nf_tables]
[43929.458701]  ? __rcu_read_unlock+0x46/0x70
[43929.458709]  nft_delset+0xff/0x110 [nf_tables]
[43929.458769]  nft_flush_table+0x16f/0x460 [nf_tables]
[43929.458830]  nf_tables_deltable+0x501/0x580 [nf_tables]

Fixes: 628bd3e49c ("netfilter: nf_tables: drop map element references from preparation phase")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-04-17 17:43:11 +02:00
Pablo Neira Ayuso 29b359cf6d netfilter: nft_set_pipapo: walk over current view on netlink dump
The generation mask can be updated while netlink dump is in progress.
The pipapo set backend walk iterator cannot rely on it to infer what
view of the datastructure is to be used. Add notation to specify if user
wants to read/update the set.

Based on patch from Florian Westphal.

Fixes: 2b84e215f8 ("netfilter: nft_set_pipapo: .walk does not deal with generations")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-04-11 12:10:03 +02:00
Ziyang Xuan d78d867dce netfilter: nf_tables: Fix potential data-race in __nft_obj_type_get()
nft_unregister_obj() can concurrent with __nft_obj_type_get(),
and there is not any protection when iterate over nf_tables_objects
list in __nft_obj_type_get(). Therefore, there is potential data-race
of nf_tables_objects list entry.

Use list_for_each_entry_rcu() to iterate over nf_tables_objects
list in __nft_obj_type_get(), and use rcu_read_lock() in the caller
nft_obj_type_get() to protect the entire type query process.

Fixes: e50092404c ("netfilter: nf_tables: add stateful objects")
Signed-off-by: Ziyang Xuan <william.xuanziyang@huawei.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-04-11 12:09:11 +02:00
Ziyang Xuan f969eb84ce netfilter: nf_tables: Fix potential data-race in __nft_expr_type_get()
nft_unregister_expr() can concurrent with __nft_expr_type_get(),
and there is not any protection when iterate over nf_tables_expressions
list in __nft_expr_type_get(). Therefore, there is potential data-race
of nf_tables_expressions list entry.

Use list_for_each_entry_rcu() to iterate over nf_tables_expressions
list in __nft_expr_type_get(), and use rcu_read_lock() in the caller
nft_expr_type_get() to protect the entire type query process.

Fixes: ef1f7df917 ("netfilter: nf_tables: expression ops overloading")
Signed-off-by: Ziyang Xuan <william.xuanziyang@huawei.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-04-11 12:08:34 +02:00
Pablo Neira Ayuso 1bc83a019b netfilter: nf_tables: discard table flag update with pending basechain deletion
Hook unregistration is deferred to the commit phase, same occurs with
hook updates triggered by the table dormant flag. When both commands are
combined, this results in deleting a basechain while leaving its hook
still registered in the core.

Fixes: 179d9ba555 ("netfilter: nf_tables: fix table flag updates")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-04-04 11:38:35 +02:00
Ziyang Xuan 24225011d8 netfilter: nf_tables: Fix potential data-race in __nft_flowtable_type_get()
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>
2024-04-04 11:38:34 +02:00
Pablo Neira Ayuso 994209ddf4 netfilter: nf_tables: reject new basechain after table flag update
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>
2024-04-04 11:34:42 +02:00
Pablo Neira Ayuso 24cea96770 netfilter: nf_tables: flush pending destroy work before exit_net release
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>
2024-04-04 11:34:42 +02:00
Pablo Neira Ayuso 0d459e2ffb netfilter: nf_tables: release mutex after nft_gc_seq_end from abort path
The commit mutex should not be released during the critical section
between nft_gc_seq_begin() and nft_gc_seq_end(), otherwise, async GC
worker could collect expired objects and get the released commit lock
within the same GC sequence.

nf_tables_module_autoload() temporarily releases the mutex to load
module dependencies, then it goes back to replay the transaction again.
Move it at the end of the abort phase after nft_gc_seq_end() is called.

Cc: stable@vger.kernel.org
Fixes: 720344340f ("netfilter: nf_tables: GC transaction race with abort path")
Reported-by: Kuan-Ting Chen <hexrabbit@devco.re>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-04-04 11:34:42 +02:00
Pablo Neira Ayuso a45e688957 netfilter: nf_tables: release batch on table validation from abort path
Unlike early commit path stage which triggers a call to abort, an
explicit release of the batch is required on abort, otherwise mutex is
released and commit_list remains in place.

Add WARN_ON_ONCE to ensure commit_list is empty from the abort path
before releasing the mutex.

After this patch, commit_list is always assumed to be empty before
grabbing the mutex, therefore

  03c1f1ef15 ("netfilter: Cleanup nft_net->module_list from nf_tables_exit_net()")

only needs to release the pending modules for registration.

Cc: stable@vger.kernel.org
Fixes: c0391b6ab8 ("netfilter: nf_tables: missing validation from the abort path")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-04-04 11:34:41 +02:00
Pablo Neira Ayuso 216e7bf740 netfilter: nf_tables: skip netdev hook unregistration if table is dormant
Skip hook unregistration when adding or deleting devices from an
existing netdev basechain. Otherwise, commit/abort path try to
unregister hooks which not enabled.

Fixes: b9703ed44f ("netfilter: nf_tables: support for adding new devices to an existing netdev chain")
Fixes: 7d937b1071 ("netfilter: nf_tables: support for deleting devices in an existing netdev chain")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-03-28 03:54:01 +01:00
Pablo Neira Ayuso 1e1fb6f00f netfilter: nf_tables: reject table flag and netdev basechain updates
netdev basechain updates are stored in the transaction object hook list.
When setting on the table dormant flag, it iterates over the existing
hooks in the basechain. Thus, skipping the hooks that are being
added/deleted in this transaction, which leaves hook registration in
inconsistent state.

Reject table flag updates in combination with netdev basechain updates
in the same batch:

- Update table flags and add/delete basechain: Check from basechain update
  path if there are pending flag updates for this table.
- add/delete basechain and update table flags: Iterate over the transaction
  list to search for basechain updates from the table update path.

In both cases, the batch is rejected. Based on suggestion from Florian Westphal.

Fixes: b9703ed44f ("netfilter: nf_tables: support for adding new devices to an existing netdev chain")
Fixes: 7d937b1071 ("netfilter: nf_tables: support for deleting devices in an existing netdev chain")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-03-28 03:54:01 +01:00
Pablo Neira Ayuso b32ca27fa2 netfilter: nf_tables: reject destroy command to remove basechain hooks
Report EOPNOTSUPP if NFT_MSG_DESTROYCHAIN is used to delete hooks in an
existing netdev basechain, thus, only NFT_MSG_DELCHAIN is allowed.

Fixes: 7d937b1071 ("netfilter: nf_tables: support for deleting devices in an existing netdev chain")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-03-28 03:54:01 +01:00
Quan Tian 7eaf837a4e netfilter: nf_tables: Fix a memory leak in nf_tables_updchain
If nft_netdev_register_hooks() fails, the memory associated with
nft_stats is not freed, causing a memory leak.

This patch fixes it by moving nft_stats_alloc() down after
nft_netdev_register_hooks() succeeds.

Fixes: b9703ed44f ("netfilter: nf_tables: support for adding new devices to an existing netdev chain")
Signed-off-by: Quan Tian <tianquan23@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-03-21 12:12:06 +01:00
Pablo Neira Ayuso 4a0e7f2dec netfilter: nf_tables: do not compare internal table flags on updates
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>
2024-03-21 00:21:55 +01:00
Jakub Kicinski e3afe5dd3a Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR.

No conflicts.

Adjacent changes:

net/core/page_pool_user.c
  0b11b1c5c3 ("netdev: let netlink core handle -EMSGSIZE errors")
  429679dcf7 ("page_pool: fix netlink dump stop/resume")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-03-07 10:29:36 -08:00
Pablo Neira Ayuso 552705a365 netfilter: nf_tables: mark set as dead when unbinding anonymous set with timeout
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>
2024-03-07 03:08:26 +01:00
Pablo Neira Ayuso 5f4fc4bd5c netfilter: nf_tables: reject constant set with timeout
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>
2024-03-07 00:02:42 +01:00
Pablo Neira Ayuso 16603605b6 netfilter: nf_tables: disallow anonymous set with timeout flag
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>
2024-03-07 00:02:42 +01:00
Jakub Kicinski fecc51559a Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR.

Conflicts:

net/ipv4/udp.c
  f796feabb9 ("udp: add local "peek offset enabled" flag")
  56667da739 ("net: implement lockless setsockopt(SO_PEEK_OFF)")

Adjacent changes:

net/unix/garbage.c
  aa82ac51d6 ("af_unix: Drop oob_skb ref before purging queue in GC.")
  11498715f2 ("af_unix: Remove io_uring code for GC.")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-02-22 15:29:26 -08:00
Florian Westphal 195e5f88c2 netfilter: nf_tables: use kzalloc for hook allocation
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>
2024-02-22 00:15:58 +01:00
Pablo Neira Ayuso d472e9853d netfilter: nf_tables: register hooks last when adding new chain/flowtable
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>
2024-02-22 00:14:54 +01:00
Florian Westphal bccebf6470 netfilter: nf_tables: set dormant flag on hook register failure
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>
2024-02-22 00:14:54 +01:00
Jakub Kicinski 3be042cf46 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR.

No conflicts.

Adjacent changes:

drivers/net/ethernet/stmicro/stmmac/common.h
  38cc3c6dcc ("net: stmmac: protect updates of 64-bit statistics counters")
  fd5a6a7131 ("net: stmmac: est: Per Tx-queue error count for HLBF")
  c5c3e1bfc9 ("net: stmmac: Offload queueMaxSDU from tc-taprio")

drivers/net/wireless/microchip/wilc1000/netdev.c
  c901388028 ("wifi: fill in MODULE_DESCRIPTION()s for wilc1000")
  328efda22a ("wifi: wilc1000: do not realloc workqueue everytime an interface is added")

net/unix/garbage.c
  11498715f2 ("af_unix: Remove io_uring code for GC.")
  1279f9d9de ("af_unix: Call kfree_skb() for dead unix_(sk)->oob_skb in GC.")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-02-08 15:30:33 -08:00
Pablo Neira Ayuso 7395dfacff netfilter: nf_tables: use timestamp to check for set element timeout
Add a timestamp field at the beginning of the transaction, store it
in the nftables per-netns area.

Update set backend .insert, .deactivate and sync gc path to use the
timestamp, this avoids that an element expires while control plane
transaction is still unfinished.

.lookup and .update, which are used from packet path, still use the
current time to check if the element has expired. And .get path and dump
also since this runs lockless under rcu read size lock. Then, there is
async gc which also needs to check the current time since it runs
asynchronously from a workqueue.

Fixes: c3e1b005ed ("netfilter: nf_tables: add set element timeout support")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-02-08 12:10:19 +01:00
Jakub Kicinski cf244463a2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR.

No conflicts or adjacent changes.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-02-01 15:12:37 -08:00
Pablo Neira Ayuso 776d451648 netfilter: nf_tables: restrict tunnel object to NFPROTO_NETDEV
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>
2024-01-31 23:07:04 +01:00
Pablo Neira Ayuso a128885ace netfilter: nf_tables: pass flags to set backend selection routine
No need to refetch the flag from the netlink attribute, pass the
existing flags variable which already provide validated flags.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
2024-01-29 15:43:20 +01:00
Phil Sutter 31bf508be6 netfilter: nf_tables: Implement table adoption support
Allow a new process to take ownership of a previously owned table,
useful mostly for firewall management services restarting or suspending
when idle.

By extending __NFT_TABLE_F_UPDATE, the on/off/on check in
nf_tables_updtable() also covers table adoption, although it is actually
not needed: Table adoption is irreversible because nf_tables_updtable()
rejects attempts to drop NFT_TABLE_F_OWNER so table->nlpid setting can
happen just once within the transaction.

If the transaction commences, table's nlpid and flags fields are already
set and no further action is required. If it aborts, the table returns
to orphaned state.

Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Florian Westphal <fw@strlen.de>
2024-01-29 15:43:20 +01:00
Phil Sutter da5141bbe0 netfilter: nf_tables: Introduce NFT_TABLE_F_PERSIST
This companion flag to NFT_TABLE_F_OWNER requests the kernel to keep the
table around after the process has exited. It marks such table as
orphaned (by dropping OWNER flag but keeping PERSIST flag in place),
which opens it for other processes to manipulate. For the sake of
simplicity, PERSIST flag may not be altered though.

Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Florian Westphal <fw@strlen.de>
2024-01-29 15:43:20 +01:00
Florian Westphal f342de4e2f netfilter: nf_tables: reject QUEUE/DROP verdict parameters
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>
2024-01-24 20:02:39 +01:00
Florian Westphal b462579b2b netfilter: nf_tables: restrict anonymous set and map names to 16 bytes
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>
2024-01-24 20:02:30 +01:00
Pablo Neira Ayuso 113661e074 netfilter: nf_tables: reject NFT_SET_CONCAT with not field length description
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>
2024-01-17 12:02:51 +01:00
Pablo Neira Ayuso 6b1ca88e4b netfilter: nf_tables: skip dead set elements in netlink dump
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>
2024-01-17 12:02:50 +01:00
Pablo Neira Ayuso 3ce67e3793 netfilter: nf_tables: do not allow mismatch field size and set key length
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>
2024-01-17 12:02:50 +01:00
Pablo Neira Ayuso b1db244ffd netfilter: nf_tables: check if catch-all set element is active in next generation
When deactivating the catch-all set element, check the state in the next
generation that represents this transaction.

This bug uncovered after the recent removal of the element busy mark
a2dd0233cb ("netfilter: nf_tables: remove busy mark and gc batch API").

Fixes: aaa31047a6 ("netfilter: nftables: add catch-all set element support")
Cc: stable@vger.kernel.org
Reported-by: lonial con <kongln9170@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-01-17 12:02:49 +01:00
Pablo Neira Ayuso 3c13725f43 netfilter: nf_tables: bail out if stateful expression provides no .clone
All existing NFT_EXPR_STATEFUL provide a .clone interface, remove
fallback to copy content of stateful expression since this is never
exercised and bail out if .clone interface is not defined.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-01-17 12:02:46 +01:00
Pablo Neira Ayuso 65b3bd600e netfilter: nf_tables: validate .maxattr at expression registration
struct nft_expr_info allows to store up to NFT_EXPR_MAXATTR (16)
attributes when parsing netlink attributes.

Rise a warning in case there is ever a nft expression whose .maxattr
goes beyond this number of expressions, in such case, struct nft_expr_info
needs to be updated.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-01-17 12:02:46 +01:00
Pablo Neira Ayuso 0617c3de9b netfilter: nf_tables: reject invalid set policy
Report -EINVAL in case userspace provides a unsupported set backend
policy.

Fixes: c50b960ccc ("netfilter: nf_tables: implement proper set selection")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-01-17 12:02:45 +01:00
Jakub Kicinski e63c1822ac Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR.

Conflicts:

drivers/net/ethernet/broadcom/bnxt/bnxt.c
  e009b2efb7 ("bnxt_en: Remove mis-applied code from bnxt_cfg_ntp_filters()")
  0f2b214779 ("bnxt_en: Fix compile error without CONFIG_RFS_ACCEL")
https://lore.kernel.org/all/20240105115509.225aa8a2@canb.auug.org.au/

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-01-04 18:06:46 -08:00
Pablo Neira Ayuso aaba7ddc85 netfilter: nf_tables: validate chain type update if available
Parse netlink attribute containing the chain type in this update, to
bail out if this is different from the existing type.

Otherwise, it is possible to define a chain with the same name, hook and
priority but different type, which is silently ignored.

Fixes: 96518518cc ("netfilter: add nftables")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-12-22 12:15:28 +01:00
Florian Westphal 08e4c8c591 netfilter: nf_tables: mark newset as dead on transaction abort
If a transaction is aborted, we should mark the to-be-released NEWSET dead,
just like commit path does for DEL and DESTROYSET commands.

In both cases all remaining elements will be released via
set->ops->destroy().

The existing abort code does NOT post the actual release to the work queue.
Also the entire __nf_tables_abort() function is wrapped in gc_seq
begin/end pair.

Therefore, async gc worker will never try to release the pending set
elements, as gc sequence is always stale.

It might be possible to speed up transaction aborts via work queue too,
this would result in a race and a possible use-after-free.

So fix this before it becomes an issue.

Fixes: 5f68718b34 ("netfilter: nf_tables: GC transaction API to avoid race with control plane")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-12-22 12:08:38 +01:00
Phil Sutter 3d483faa66 netfilter: nf_tables: Add locking for NFT_MSG_GETSETELEM_RESET requests
Set expressions' dump callbacks are not concurrency-safe per-se with
reset bit set. If two CPUs reset the same element at the same time,
values may underrun at least with element-attached counters and quotas.

Prevent this by introducing dedicated callbacks for nfnetlink and the
asynchronous dump handling to serialize access.

Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-12-22 12:08:38 +01:00
Phil Sutter f649be6d9c netfilter: nf_tables: Introduce nft_set_dump_ctx_init()
This is a wrapper around nft_ctx_init() for use in
nf_tables_getsetelem() and a resetting equivalent introduced later.

Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-12-22 12:08:37 +01:00
Phil Sutter 5896e861a7 netfilter: nf_tables: Pass const set to nft_get_set_elem
The function is not supposed to alter the set, passing the pointer as
const is fine and merely requires to adjust signatures of two called
functions as well.

Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-12-22 12:08:37 +01:00
Pablo Neira Ayuso 7315dc1e12 netfilter: nf_tables: skip set commit for deleted/destroyed sets
NFT_MSG_DELSET deactivates all elements in the set, skip
set->ops->commit() to avoid the unnecessary clone (for the pipapo case)
as well as the sync GC cycle, which could deactivate again expired
elements in such set.

Fixes: 5f68718b34 ("netfilter: nf_tables: GC transaction API to avoid race with control plane")
Reported-by: Kevin Rich <kevinrich1337@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-12-20 13:48:00 +01:00
Pablo Neira Ayuso f6e1532a26 netfilter: nf_tables: validate family when identifying table via handle
Validate table family when looking up for it via NFTA_TABLE_HANDLE.

Fixes: 3ecbfd65f5 ("netfilter: nf_tables: allocate handle and delete objects via handle")
Reported-by: Xingyuan Mo <hdthky0@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-12-06 17:15:43 +01:00
Pablo Neira Ayuso 8837ba3e58 netfilter: nf_tables: split async and sync catchall in two functions
list_for_each_entry_safe() does not work for the async case which runs
under RCU, therefore, split GC logic for catchall in two functions
instead, one for each of the sync and async GC variants.

The catchall sync GC variant never sees a _DEAD bit set on ever, thus,
this handling is removed in such case, moreover, allocate GC sync batch
via GFP_KERNEL.

Fixes: 93995bf4af ("netfilter: nf_tables: remove catchall element in GC sync path")
Reported-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-11-14 16:16:21 +01:00
Pablo Neira Ayuso a7d5a955bf netfilter: nf_tables: bogus ENOENT when destroying element which does not exist
destroy element command bogusly reports ENOENT in case a set element
does not exist. ENOENT errors are skipped, however, err is still set
and propagated to userspace.

 # nft destroy element ip raw BLACKLIST { 1.2.3.4 }
 Error: Could not process rule: No such file or directory
 destroy element ip raw BLACKLIST { 1.2.3.4 }
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Fixes: f80a612dd7 ("netfilter: nf_tables: add support to destroy operation")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-11-14 16:16:21 +01:00