This nfnl subsystem allows to dump the list of all active netfiler hooks,
e.g. defrag, conntrack, nf/ip/arp/ip6tables and so on.

This helps to see what kind of features are currently enabled in
the network stack.

Sample output from nft tool using this infra:

 $ nft list hook ip input
 family ip hook input {
   +0000000010 nft_do_chain_inet [nf_tables] # nft table firewalld INPUT
   +0000000100 nf_nat_ipv4_local_in [nf_nat]
   +2147483647 ipv4_confirm [nf_conntrack]
 }
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

This will allow a followup patch to treat the 'ops->priv' pointer
as nft_chain argument without having to first walk the table/chains
to check if there is a matching base chain pointer.
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

Currently the aging period for tcp/udp connections is hard coded to
30 seconds. Aged tcp/udp connections configure a hard coded 120/30
seconds pickup timeout for conntrack.
This configuration may be too aggressive or permissive for some users.

Dynamically configure the nf flow table GC timeout intervals according
to the user defined values.
Signed-off-by: NOz Shlomo <ozsh@nvidia.com>
Reviewed-by: NPaul Blakey <paulb@nvidia.com>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

UDP connections may be offloaded from nf conntrack to nf flow table.
Offloaded connections are aged after 30 seconds of inactivity.
Once aged, ownership is returned to conntrack with a hard coded pickup
time of 30 seconds, after which the connection may be deleted.
eted. The current aging intervals may be too aggressive for some users.

Provide users with the ability to control the nf flow table offload
aging and pickup time intervals via sysctl parameter as a pre-step for
configuring the nf flow table GC timeout intervals.
Signed-off-by: NOz Shlomo <ozsh@nvidia.com>
Reviewed-by: NPaul Blakey <paulb@nvidia.com>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

TCP connections may be offloaded from nf conntrack to nf flow table.
Offloaded connections are aged after 30 seconds of inactivity.
Once aged, ownership is returned to conntrack with a hard coded pickup
time of 120 seconds, after which the connection may be deleted.
eted. The current aging intervals may be too aggressive for some users.

Provide users with the ability to control the nf flow table offload
aging and pickup time intervals via sysctl parameter as a pre-step for
configuring the nf flow table GC timeout intervals.
Signed-off-by: NOz Shlomo <ozsh@nvidia.com>
Reviewed-by: NPaul Blakey <paulb@nvidia.com>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

Consolidate call to net_generic(net, nf_conntrack_net_id) in this
wrapper function.
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

Replace nft_ctx_init_from_setattr() by nft_table_lookup().

This patch also disentangles nf_tables_delset() where NFTA_SET_TABLE is
required while nft_ctx_init_from_setattr() allows it to be optional.

From the nf_tables_delset() path, this also allows to set up the context
structure when it is needed.

Removing this helper function saves us 14 LoC, so it is not helping to
consolidate code.
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

Replace nft_ctx_init_from_elemattr() by nft_table_lookup() and set up
the context structure right before it is really needed.

Moreover, nft_ctx_init_from_elemattr() is setting up the context
structure for codepaths where this is not really needed at all.

This helper function is also not helping to consolidate code, removing
it saves us 4 LoC.
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

Update the nfnl_info structure to add a pointer to the nfnetlink header.
This simplifies the existing codebase since this header is usually
accessed. Update existing clients to use this new field.
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

nf_conntrack_h323_main.c:198:6: warning: format specifies type 'unsigned short' but
xt_AUDIT.c:121:9: warning: format specifies type 'unsigned char' but the argument has type 'int' [-Wformat]
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

W=1:
net/netfilter/nft_set_pipapo_avx2.c:159: warning: Excess function parameter 'len' description in 'nft_pipapo_avx2_refill'
net/netfilter/nft_set_pipapo_avx2.c:1124: warning: Function parameter or member 'key' not described in 'nft_pipapo_avx2_lookup'
net/netfilter/nft_set_pipapo_avx2.c:1124: warning: Excess function parameter 'elem' description in 'nft_pipapo_avx2_lookup'
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

Init it on demand in the nft_compat expression.  This reduces size
of nft_pktinfo from 48 to 24 bytes on x86_64.
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

The functions pass extra skb arg, but either its not used or the helpers
can already access it via pkt->skb.
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

This allows to change storage placement later on without changing readers.
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

This allows to change storage placement later on without changing readers.
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

Replace netlink_unicast() calls by nfnetlink_unicast() which already
deals with translating EAGAIN to ENOBUFS as the nfnetlink core expects.

nfnetlink_unicast() calls nlmsg_unicast() which returns zero in case of
success, otherwise the netlink core function netlink_rcv_skb() turns
err > 0 into an acknowlegment.
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

Variable 'ret' is set to zero but this value is never read as it is
overwritten with a new value later on, hence it is a redundant
assignment and can be removed

Clean up the following clang-analyzer warning:

net/netfilter/xt_CT.c:175:2: warning: Value stored to 'ret' is never read [clang-analyzer-deadcode.DeadStores]
Reported-by: NAbaci Robot <abaci@linux.alibaba.com>
Signed-off-by: NYang Li <yang.lee@linux.alibaba.com>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

We've seen this spin_lock show up high in profiles. Let's introduce a
lockless version. I've tested this using pktgen_sample01_simple.sh.
Signed-off-by: NJason Baron <jbaron@akamai.com>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

Remove leading spaces before tabs in Kconfig file(s) by running the
following command:

  $ find net/netfilter -name 'Kconfig*' | xargs sed -r -i 's/^[ ]+\t/\t/'
Signed-off-by: NJuerg Haefliger <juergh@canonical.com>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

Extend nft_set_do_lookup() to use direct calls when retpoline feature
is enabled.
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

Followup patch will add a CONFIG_RETPOLINE wrapper to avoid
the ops->lookup() indirection cost for retpoline builds.
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

We don't need a valid MXCSR state for the lookup routines, none of
the instructions we use rely on or affect any bit in the MXCSR
register.

Instead of calling kernel_fpu_begin(), we can pass 0 as mask to
kernel_fpu_begin_mask() and spare one LDMXCSR instruction.

Commit 49200d17 ("x86/fpu/64: Don't FNINIT in kernel_fpu_begin()")
already speeds up lookups considerably, and by dropping the MCXSR
initialisation we can now get a much smaller, but measurable, increase
in matching rates.

The table below reports matching rates and a wild approximation of
clock cycles needed for a match in a "port,net" test with 10 entries
from selftests/netfilter/nft_concat_range.sh, limited to the first
field, i.e. the port (with nft_set_rbtree initialisation skipped), run
on a single AMD Epyc 7351 thread (2.9GHz, 512 KiB L1D$, 8 MiB L2$).

The (very rough) estimation of clock cycles is obtained by simply
dividing frequency by matching rate. The "cycles spared" column refers
to the difference in cycles compared to the previous row, and the rate
increase also refers to the previous row. Results are averages of six
runs.

Merely for context, I'm also reporting packet rates obtained by
skipping kernel_fpu_begin() and kernel_fpu_end() altogether (which
shows a very limited impact now), as well as skipping the whole lookup
function, compared to simply counting and dropping all packets using
the netdev hook drop (see nft_concat_range.sh for details). This
workload also includes packet generation with pktgen and the receive
path of veth.

                                      |matching|  est.  | cycles |  rate  |
                                      |  rate  | cycles | spared |increase|
                                      | (Mpps) |        |        |        |
--------------------------------------|--------|--------|--------|--------|
FNINIT, LDMXCSR (before 49200d17) |  5.245 |    553 |      - |      - |
LDMXCSR only (with 49200d17)      |  6.347 |    457 |     96 |  21.0% |
Without LDMXCSR (this patch)          |  6.461 |    449 |      8 |   1.8% |
-------- for reference only: ---------|--------|--------|--------|--------|
Without kernel_fpu_begin()            |  6.513 |    445 |      4 |   0.8% |
Without actual matching (return true) |  7.649 |    379 |     66 |  17.4% |
Without lookup operation (netdev drop)| 10.320 |    281 |     98 |  34.9% |

The clock cycles spared by avoiding LDMXCSR appear to be in line with CPI
and latency indicated in the manuals of comparable architectures: Intel
Skylake (CPI: 1, latency: 7) and AMD 12h (latency: 12) -- I couldn't find
this information for AMD 17h.
Signed-off-by: NStefano Brivio <sbrivio@redhat.com>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

Chunks are SCTP header extensions similar in implementation to IPv6
extension headers or TCP options. Reusing exthdr expression to find and
extract field values from them is therefore pretty straightforward.

For now, this supports extracting data from chunks at a fixed offset
(and length) only - chunks themselves are an extensible data structure;
in order to make all fields available, a nested extension search is
needed.
Signed-off-by: NPhil Sutter <phil@nwl.cc>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

Arturo reported this backtrace:

[709732.358791] WARNING: CPU: 3 PID: 456 at arch/x86/kernel/fpu/core.c:128 kernel_fpu_begin_mask+0xae/0xe0
[709732.358793] Modules linked in: binfmt_misc nft_nat nft_chain_nat nf_nat nft_counter nft_ct nf_tables nf_conntrack_netlink nfnetlink 8021q garp stp mrp llc vrf intel_rapl_msr intel_rapl_common skx_edac nfit libnvdimm ipmi_ssif x86_pkg_temp_thermal intel_powerclamp coretemp crc32_pclmul mgag200 ghash_clmulni_intel drm_kms_helper cec aesni_intel drm libaes crypto_simd cryptd glue_helper mei_me dell_smbios iTCO_wdt evdev intel_pmc_bxt iTCO_vendor_support dcdbas pcspkr rapl dell_wmi_descriptor wmi_bmof sg i2c_algo_bit watchdog mei acpi_ipmi ipmi_si button nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ipmi_devintf ipmi_msghandler ip_tables x_tables autofs4 ext4 crc16 mbcache jbd2 dm_mod raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor sd_mod t10_pi crc_t10dif crct10dif_generic raid6_pq libcrc32c crc32c_generic raid1 raid0 multipath linear md_mod ahci libahci tg3 libata xhci_pci libphy xhci_hcd ptp usbcore crct10dif_pclmul crct10dif_common bnxt_en crc32c_intel scsi_mod
[709732.358941]  pps_core i2c_i801 lpc_ich i2c_smbus wmi usb_common
[709732.358957] CPU: 3 PID: 456 Comm: jbd2/dm-0-8 Not tainted 5.10.0-0.bpo.5-amd64 #1 Debian 5.10.24-1~bpo10+1
[709732.358959] Hardware name: Dell Inc. PowerEdge R440/04JN2K, BIOS 2.9.3 09/23/2020
[709732.358964] RIP: 0010:kernel_fpu_begin_mask+0xae/0xe0
[709732.358969] Code: ae 54 24 04 83 e3 01 75 38 48 8b 44 24 08 65 48 33 04 25 28 00 00 00 75 33 48 83 c4 10 5b c3 65 8a 05 5e 21 5e 76 84 c0 74 92 <0f> 0b eb 8e f0 80 4f 01 40 48 81 c7 00 14 00 00 e8 dd fb ff ff eb
[709732.358972] RSP: 0018:ffffbb9700304740 EFLAGS: 00010202
[709732.358976] RAX: 0000000000000001 RBX: 0000000000000003 RCX: 0000000000000001
[709732.358979] RDX: ffffbb9700304970 RSI: ffff922fe1952e00 RDI: 0000000000000003
[709732.358981] RBP: ffffbb9700304970 R08: ffff922fc868a600 R09: ffff922fc711e462
[709732.358984] R10: 000000000000005f R11: ffff922ff0b27180 R12: ffffbb9700304960
[709732.358987] R13: ffffbb9700304b08 R14: ffff922fc664b6c8 R15: ffff922fc664b660
[709732.358990] FS:  0000000000000000(0000) GS:ffff92371fec0000(0000) knlGS:0000000000000000
[709732.358993] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[709732.358996] CR2: 0000557a6655bdd0 CR3: 000000026020a001 CR4: 00000000007706e0
[709732.358999] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[709732.359001] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[709732.359003] PKRU: 55555554
[709732.359005] Call Trace:
[709732.359009]  <IRQ>
[709732.359035]  nft_pipapo_avx2_lookup+0x4c/0x1cba [nf_tables]
[709732.359046]  ? sched_clock+0x5/0x10
[709732.359054]  ? sched_clock_cpu+0xc/0xb0
[709732.359061]  ? record_times+0x16/0x80
[709732.359068]  ? plist_add+0xc1/0x100
[709732.359073]  ? psi_group_change+0x47/0x230
[709732.359079]  ? skb_clone+0x4d/0xb0
[709732.359085]  ? enqueue_task_rt+0x22b/0x310
[709732.359098]  ? bnxt_start_xmit+0x1e8/0xaf0 [bnxt_en]
[709732.359102]  ? packet_rcv+0x40/0x4a0
[709732.359121]  nft_lookup_eval+0x59/0x160 [nf_tables]
[709732.359133]  nft_do_chain+0x350/0x500 [nf_tables]
[709732.359152]  ? nft_lookup_eval+0x59/0x160 [nf_tables]
[709732.359163]  ? nft_do_chain+0x364/0x500 [nf_tables]
[709732.359172]  ? fib4_rule_action+0x6d/0x80
[709732.359178]  ? fib_rules_lookup+0x107/0x250
[709732.359184]  nft_nat_do_chain+0x8a/0xf2 [nft_chain_nat]
[709732.359193]  nf_nat_inet_fn+0xea/0x210 [nf_nat]
[709732.359202]  nf_nat_ipv4_out+0x14/0xa0 [nf_nat]
[709732.359207]  nf_hook_slow+0x44/0xc0
[709732.359214]  ip_output+0xd2/0x100
[709732.359221]  ? __ip_finish_output+0x210/0x210
[709732.359226]  ip_forward+0x37d/0x4a0
[709732.359232]  ? ip4_key_hashfn+0xb0/0xb0
[709732.359238]  ip_sublist_rcv_finish+0x4f/0x60
[709732.359243]  ip_sublist_rcv+0x196/0x220
[709732.359250]  ? ip_rcv_finish_core.isra.22+0x400/0x400
[709732.359255]  ip_list_rcv+0x137/0x160
[709732.359264]  __netif_receive_skb_list_core+0x29b/0x2c0
[709732.359272]  netif_receive_skb_list_internal+0x1a6/0x2d0
[709732.359280]  gro_normal_list.part.156+0x19/0x40
[709732.359286]  napi_complete_done+0x67/0x170
[709732.359298]  bnxt_poll+0x105/0x190 [bnxt_en]
[709732.359304]  ? irqentry_exit+0x29/0x30
[709732.359309]  ? asm_common_interrupt+0x1e/0x40
[709732.359315]  net_rx_action+0x144/0x3c0
[709732.359322]  __do_softirq+0xd5/0x29c
[709732.359329]  asm_call_irq_on_stack+0xf/0x20
[709732.359332]  </IRQ>
[709732.359339]  do_softirq_own_stack+0x37/0x40
[709732.359346]  irq_exit_rcu+0x9d/0xa0
[709732.359353]  common_interrupt+0x78/0x130
[709732.359358]  asm_common_interrupt+0x1e/0x40
[709732.359366] RIP: 0010:crc_41+0x0/0x1e [crc32c_intel]
[709732.359370] Code: ff ff f2 4d 0f 38 f1 93 a8 fe ff ff f2 4c 0f 38 f1 81 b0 fe ff ff f2 4c 0f 38 f1 8a b0 fe ff ff f2 4d 0f 38 f1 93 b0 fe ff ff <f2> 4c 0f 38 f1 81 b8 fe ff ff f2 4c 0f 38 f1 8a b8 fe ff ff f2 4d
[709732.359373] RSP: 0018:ffffbb97008dfcd0 EFLAGS: 00000246
[709732.359377] RAX: 000000000000002a RBX: 0000000000000400 RCX: ffff922fc591dd50
[709732.359379] RDX: ffff922fc591dea0 RSI: 0000000000000a14 RDI: ffffffffc00dddc0
[709732.359382] RBP: 0000000000001000 R08: 000000000342d8c3 R09: 0000000000000000
[709732.359384] R10: 0000000000000000 R11: ffff922fc591dff0 R12: ffffbb97008dfe58
[709732.359386] R13: 000000000000000a R14: ffff922fd2b91e80 R15: ffff922fef83fe38
[709732.359395]  ? crc_43+0x1e/0x1e [crc32c_intel]
[709732.359403]  ? crc32c_pcl_intel_update+0x97/0xb0 [crc32c_intel]
[709732.359419]  ? jbd2_journal_commit_transaction+0xaec/0x1a30 [jbd2]
[709732.359425]  ? irq_exit_rcu+0x3e/0xa0
[709732.359447]  ? kjournald2+0xbd/0x270 [jbd2]
[709732.359454]  ? finish_wait+0x80/0x80
[709732.359470]  ? commit_timeout+0x10/0x10 [jbd2]
[709732.359476]  ? kthread+0x116/0x130
[709732.359481]  ? kthread_park+0x80/0x80
[709732.359488]  ? ret_from_fork+0x1f/0x30
[709732.359494] ---[ end trace 081a19978e5f09f5 ]---

that is, nft_pipapo_avx2_lookup() uses the FPU running from a softirq
that interrupted a kthread, also using the FPU.

That's exactly the reason why irq_fpu_usable() is there: use it, and
if we can't use the FPU, fall back to the non-AVX2 version of the
lookup operation, i.e. nft_pipapo_lookup().
Reported-by: NArturo Borrero Gonzalez <arturo@netfilter.org>
Cc: <stable@vger.kernel.org> # 5.6.x
Fixes: 7400b063 ("nft_set_pipapo: Introduce AVX2-based lookup implementation")
Signed-off-by: NStefano Brivio <sbrivio@redhat.com>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

Offloading conns could fail for multiple reasons and a hw refresh bit is
set to try to reoffload it in next sw packet.
But it could be in some cases and future points that the hw refresh bit
is not set but a refresh could succeed.
Remove the hw refresh bit and do offload refresh if requested.
There won't be a new work entry if a work is already pending
anyway as there is the hw pending bit.

Fixes: 8b3646d6 ("net/sched: act_ct: Support refreshing the flow table entries")
Signed-off-by: NRoi Dayan <roid@nvidia.com>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

User space could ask for very large hash tables, we need to make sure
our size computations wont overflow.

nf_tables_newset() needs to double check the u64 size
will fit into size_t field.

Fixes: 0ed6389c ("netfilter: nf_tables: rename set implementations")
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

Number of buckets being stored in 32bit variables, we have to
ensure that no overflows occur in nft_hash_buckets()

syzbot injected a size == 0x40000000 and reported:

UBSAN: shift-out-of-bounds in ./include/linux/log2.h:57:13
shift exponent 64 is too large for 64-bit type 'long unsigned int'
CPU: 1 PID: 29539 Comm: syz-executor.4 Not tainted 5.12.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x141/0x1d7 lib/dump_stack.c:120
 ubsan_epilogue+0xb/0x5a lib/ubsan.c:148
 __ubsan_handle_shift_out_of_bounds.cold+0xb1/0x181 lib/ubsan.c:327
 __roundup_pow_of_two include/linux/log2.h:57 [inline]
 nft_hash_buckets net/netfilter/nft_set_hash.c:411 [inline]
 nft_hash_estimate.cold+0x19/0x1e net/netfilter/nft_set_hash.c:652
 nft_select_set_ops net/netfilter/nf_tables_api.c:3586 [inline]
 nf_tables_newset+0xe62/0x3110 net/netfilter/nf_tables_api.c:4322
 nfnetlink_rcv_batch+0xa09/0x24b0 net/netfilter/nfnetlink.c:488
 nfnetlink_rcv_skb_batch net/netfilter/nfnetlink.c:612 [inline]
 nfnetlink_rcv+0x3af/0x420 net/netfilter/nfnetlink.c:630
 netlink_unicast_kernel net/netlink/af_netlink.c:1312 [inline]
 netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1338
 netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1927
 sock_sendmsg_nosec net/socket.c:654 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:674
 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2350
 ___sys_sendmsg+0xf3/0x170 net/socket.c:2404
 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2433
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46

Fixes: 0ed6389c ("netfilter: nf_tables: rename set implementations")
Signed-off-by: NEric Dumazet <edumazet@google.com>
Reported-by: Nsyzbot <syzkaller@googlegroups.com>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

Release object name if userdata allocation fails.

Fixes: b131c964 ("netfilter: nf_tables: add userdata support for nft_object")
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

Several conntrack helpers and the TCP tracker assume that
skb_header_pointer() never fails based on upfront header validation.
Even if this should not ever happen, BUG_ON() is a too drastic measure,
remove them.
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

Do not assume that the tcph->doff field is correct when parsing for TCP
options, skb_header_pointer() might fail to fetch these bits.

Fixes: 11eeef41 ("netfilter: passive OS fingerprint xtables match")
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

Reported by syzbot :
BUG: sleeping function called from invalid context at include/linux/sched/mm.h:201
in_atomic(): 0, irqs_disabled(): 0, non_block: 0, pid: 26899, name: syz-executor.5
1 lock held by syz-executor.5/26899:
 #0: ffffffff8bf797a0 (rcu_read_lock){....}-{1:2}, at: nfnetlink_get_subsys net/netfilter/nfnetlink.c:148 [inline]
 #0: ffffffff8bf797a0 (rcu_read_lock){....}-{1:2}, at: nfnetlink_rcv_msg+0x1da/0x1300 net/netfilter/nfnetlink.c:226
Preemption disabled at:
[<ffffffff8917799e>] preempt_schedule_irq+0x3e/0x90 kernel/sched/core.c:5533
CPU: 1 PID: 26899 Comm: syz-executor.5 Not tainted 5.12.0-next-20210504-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x141/0x1d7 lib/dump_stack.c:120
 ___might_sleep.cold+0x1f1/0x237 kernel/sched/core.c:8338
 might_alloc include/linux/sched/mm.h:201 [inline]
 slab_pre_alloc_hook mm/slab.h:500 [inline]
 slab_alloc_node mm/slub.c:2845 [inline]
 kmem_cache_alloc_node+0x33d/0x3e0 mm/slub.c:2960
 __alloc_skb+0x20b/0x340 net/core/skbuff.c:413
 alloc_skb include/linux/skbuff.h:1107 [inline]
 nlmsg_new include/net/netlink.h:953 [inline]
 netlink_ack+0x1ed/0xaa0 net/netlink/af_netlink.c:2437
 netlink_rcv_skb+0x33d/0x420 net/netlink/af_netlink.c:2508
 nfnetlink_rcv+0x1ac/0x420 net/netfilter/nfnetlink.c:650
 netlink_unicast_kernel net/netlink/af_netlink.c:1312 [inline]
 netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1338
 netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1927
 sock_sendmsg_nosec net/socket.c:654 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:674
 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2350
 ___sys_sendmsg+0xf3/0x170 net/socket.c:2404
 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2433
 do_syscall_64+0x3a/0xb0 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x4665f9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fa8a03ee188 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 00000000004665f9
RDX: 0000000000000000 RSI: 0000000020000480 RDI: 0000000000000004
RBP: 00000000004bfce1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60
R13: 00007fffe864480f R14: 00007fa8a03ee300 R15: 0000000000022000

================================================
WARNING: lock held when returning to user space!
5.12.0-next-20210504-syzkaller #0 Tainted: G        W
------------------------------------------------
syz-executor.5/26899 is leaving the kernel with locks still held!
1 lock held by syz-executor.5/26899:
 #0: ffffffff8bf797a0 (rcu_read_lock){....}-{1:2}, at: nfnetlink_get_subsys net/netfilter/nfnetlink.c:148 [inline]
 #0: ffffffff8bf797a0 (rcu_read_lock){....}-{1:2}, at: nfnetlink_rcv_msg+0x1da/0x1300 net/netfilter/nfnetlink.c:226
------------[ cut here ]------------
WARNING: CPU: 0 PID: 26899 at kernel/rcu/tree_plugin.h:359 rcu_note_context_switch+0xfd/0x16e0 kernel/rcu/tree_plugin.h:359
Modules linked in:
CPU: 0 PID: 26899 Comm: syz-executor.5 Tainted: G        W         5.12.0-next-20210504-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:rcu_note_context_switch+0xfd/0x16e0 kernel/rcu/tree_plugin.h:359
Code: 48 89 fa 48 c1 ea 03 0f b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 2e 0d 00 00 8b bd cc 03 00 00 85 ff 7e 02 <0f> 0b 65 48 8b 2c 25 00 f0 01 00 48 8d bd cc 03 00 00 48 b8 00 00
RSP: 0000:ffffc90002fffdb0 EFLAGS: 00010002
RAX: 0000000000000007 RBX: ffff8880b9c36080 RCX: ffffffff8dc99bac
RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000001
RBP: ffff88808b9d1c80 R08: 0000000000000000 R09: ffffffff8dc96917
R10: fffffbfff1b92d22 R11: 0000000000000000 R12: 0000000000000000
R13: ffff88808b9d1c80 R14: ffff88808b9d1c80 R15: ffffc90002ff8000
FS:  00007fa8a03ee700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f09896ed000 CR3: 0000000032070000 CR4: 00000000001526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __schedule+0x214/0x23e0 kernel/sched/core.c:5044
 schedule+0xcf/0x270 kernel/sched/core.c:5226
 exit_to_user_mode_loop kernel/entry/common.c:162 [inline]
 exit_to_user_mode_prepare+0x13e/0x280 kernel/entry/common.c:208
 irqentry_exit_to_user_mode+0x5/0x40 kernel/entry/common.c:314
 asm_sysvec_reschedule_ipi+0x12/0x20 arch/x86/include/asm/idtentry.h:637
RIP: 0033:0x4665f9

Fixes: 50f2db9e ("netfilter: nfnetlink: consolidate callback types")
Signed-off-by: NEric Dumazet <edumazet@google.com>
Reported-by: Nsyzbot <syzkaller@googlegroups.com>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

This extension breaks when trying to delete rules, add a new revision to
fix this.

Fixes: 5e6874cd ("[SECMARK]: Add xtables SECMARK target")
Signed-off-by: NPhil Sutter <phil@nwl.cc>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

In some configurations, the sock_cgroup_ptr() function is not available:

net/netfilter/nft_socket.c: In function 'nft_sock_get_eval_cgroupv2':
net/netfilter/nft_socket.c:47:16: error: implicit declaration of function 'sock_cgroup_ptr'; did you mean 'obj_cgroup_put'? [-Werror=implicit-function-declaration]
   47 |         cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
      |                ^~~~~~~~~~~~~~~
      |                obj_cgroup_put
net/netfilter/nft_socket.c:47:14: error: assignment to 'struct cgroup *' from 'int' makes pointer from integer without a cast [-Werror=int-conversion]
   47 |         cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
      |              ^

Change the caller to match the same #ifdef check, only calling it
when the function is defined.

Fixes: e0bb96db ("netfilter: nft_socket: add support for cgroupsv2")
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

The variable is only used in an #ifdef, causing a harmless warning:

net/netfilter/nft_socket.c: In function 'nft_socket_init':
net/netfilter/nft_socket.c:137:27: error: unused variable 'level' [-Werror=unused-variable]
  137 |         unsigned int len, level;
      |                           ^~~~~

Move it into the same #ifdef block.

Fixes: e0bb96db ("netfilter: nft_socket: add support for cgroupsv2")
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

This patch extends the set infrastructure to add a special catch-all set
element. If the lookup fails to find an element (or range) in the set,
then the catch-all element is selected. Users can specify a mapping,
expression(s) and timeout to be attached to the catch-all element.

This patch adds a catchall list to the set, this list might contain more
than one single catch-all element (e.g. in case that the catch-all
element is removed and a new one is added in the same transaction).
However, most of the time, there will be either one element or no
elements at all in this list.

The catch-all element is identified via NFT_SET_ELEM_CATCHALL flag and
such special element has no NFTA_SET_ELEM_KEY attribute. There is a new
nft_set_elem_catchall object that stores a reference to the dummy
catch-all element (catchall->elem) whose layout is the same of the set
element type to reuse the existing set element codebase.

The set size does not apply to the catch-all element, users can define a
catch-all element even if the set is full.

The check for valid set element flags hava been updates to report
EOPNOTSUPP in case userspace requests flags that are not supported when
using new userspace nftables and old kernel.
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

When binding sets to rule, validate set element data according to
set definition. This patch adds a helper function to be reused by
the catch-all set element support.
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

This patch adds nft_set_flush() which prepares for the catch-all
element support.
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

This patch adds nft_check_loops() to reuse it in the new catch-all
element codebase.
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

Rename:

- nft_set_elem_activate() to nft_set_elem_data_activate().
- nft_set_elem_deactivate() to nft_set_elem_data_deactivate().

To prepare for updates in the set element infrastructure to add support
for the special catch-all element.
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

The compat layer needs to parse untrusted input (the ruleset)
to translate it to a 64bit compatible format.

We had a number of bugs in this department in the past, so allow users
to turn this feature off.

Add CONFIG_NETFILTER_XTABLES_COMPAT kconfig knob and make it default to y
to keep existing behaviour.
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>