Commit Graph
6727 Commits
Author SHA1 Message Date
Pablo Neira AyusoandGreg Kroah-Hartman a9c87779df netfilter: nf_tables: remove redundant chain validation on register store
[ Upstream commit a67fd55f6a ]

This validation predates the introduction of the state machine that
determines when to enter slow path validation for error reporting.

Currently, table validation is perform when:

- new rule contains expressions that need validation.
- new set element with jump/goto verdict.

Validation on register store skips most checks with no basechains, still
this walks the graph searching for loops and ensuring expressions are
called from the right hook. Remove this.

Fixes: a654de8fdc ("netfilter: nf_tables: fix chain dependency validation")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-11 15:21:46 +01:00
Florian WestphalandGreg Kroah-Hartman 1816619b2f netfilter: nf_tables: allow loads only when register is initialized
[ Upstream commit 14fb07130c ]

Reject rules where a load occurs from a register that has not seen a store
early in the same rule.

commit 4c905f6740 ("netfilter: nf_tables: initialize registers in
nft_do_chain()")
had to add a unconditional memset to the nftables register space to avoid
leaking stack information to userspace.

This memset shows up in benchmarks.  After this change, this commit can
be reverted again.

Note that this breaks userspace compatibility, because theoretically
you can do

  rule 1: reg2 := meta load iif, reg2  == 1 jump ...
  rule 2: reg2 == 2 jump ...   // read access with no store in this rule

... after this change this is rejected.

Neither nftables nor iptables-nft generate such rules, each rule is
always standalone.

This resuts in a small increase of nft_ctx structure by sizeof(long).

To cope with hypothetical rulesets like the example above one could emit
on-demand "reg[x] = 0" store when generating the datapath blob in
nf_tables_commit_chain_prepare().

A patch that does this is linked to below.

For now, lets disable this.  In nf_tables, a rule is the smallest
unit that can be replaced from userspace, i.e. a hypothetical ruleset
that relies on earlier initialisations of registers can't be changed
at will as register usage would need to be coordinated.

Link: https://lore.kernel.org/netfilter-devel/20240627135330.17039-4-fw@strlen.de/
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Stable-dep-of: a67fd55f6a ("netfilter: nf_tables: remove redundant chain validation on register store")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-11 15:21:46 +01:00
Florian WestphalandGreg Kroah-Hartman fb1347c5c0 netfilter: nf_tables: pass context structure to nft_parse_register_load
[ Upstream commit 7ea0522ef8 ]

Mechanical transformation, no logical changes intended.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Stable-dep-of: a67fd55f6a ("netfilter: nf_tables: remove redundant chain validation on register store")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-11 15:21:46 +01:00
Slavin LiuandGreg Kroah-Hartman 4729ff0581 ipvs: fix ipv4 null-ptr-deref in route error path
[ Upstream commit ad891bb3d0 ]

The IPv4 code path in __ip_vs_get_out_rt() calls dst_link_failure()
without ensuring skb->dev is set, leading to a NULL pointer dereference
in fib_compute_spec_dst() when ipv4_link_failure() attempts to send
ICMP destination unreachable messages.

The issue emerged after commit ed0de45a10 ("ipv4: recompile ip options
in ipv4_link_failure") started calling __ip_options_compile() from
ipv4_link_failure(). This code path eventually calls fib_compute_spec_dst()
which dereferences skb->dev. An attempt was made to fix the NULL skb->dev
dereference in commit 0113d9c9d1 ("ipv4: fix null-deref in
ipv4_link_failure"), but it only addressed the immediate dev_net(skb->dev)
dereference by using a fallback device. The fix was incomplete because
fib_compute_spec_dst() later in the call chain still accesses skb->dev
directly, which remains NULL when IPVS calls dst_link_failure().

The crash occurs when:
1. IPVS processes a packet in NAT mode with a misconfigured destination
2. Route lookup fails in __ip_vs_get_out_rt() before establishing a route
3. The error path calls dst_link_failure(skb) with skb->dev == NULL
4. ipv4_link_failure() → ipv4_send_dest_unreach() →
   __ip_options_compile() → fib_compute_spec_dst()
5. fib_compute_spec_dst() dereferences NULL skb->dev

Apply the same fix used for IPv6 in commit 326bf17ea5 ("ipvs: fix
ipv6 route unreach panic"): set skb->dev from skb_dst(skb)->dev before
calling dst_link_failure().

KASAN: null-ptr-deref in range [0x0000000000000328-0x000000000000032f]
CPU: 1 PID: 12732 Comm: syz.1.3469 Not tainted 6.6.114 #2
RIP: 0010:__in_dev_get_rcu include/linux/inetdevice.h:233
RIP: 0010:fib_compute_spec_dst+0x17a/0x9f0 net/ipv4/fib_frontend.c:285
Call Trace:
  <TASK>
  spec_dst_fill net/ipv4/ip_options.c:232
  spec_dst_fill net/ipv4/ip_options.c:229
  __ip_options_compile+0x13a1/0x17d0 net/ipv4/ip_options.c:330
  ipv4_send_dest_unreach net/ipv4/route.c:1252
  ipv4_link_failure+0x702/0xb80 net/ipv4/route.c:1265
  dst_link_failure include/net/dst.h:437
  __ip_vs_get_out_rt+0x15fd/0x19e0 net/netfilter/ipvs/ip_vs_xmit.c:412
  ip_vs_nat_xmit+0x1d8/0xc80 net/netfilter/ipvs/ip_vs_xmit.c:764

Fixes: ed0de45a10 ("ipv4: recompile ip options in ipv4_link_failure")
Signed-off-by: Slavin Liu <slavin452@gmail.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-11 15:21:46 +01:00
Fernando Fernandez ManceraandGreg Kroah-Hartman 325eb61bb3 netfilter: nf_conncount: fix leaked ct in error paths
[ Upstream commit 2e2a720766 ]

There are some situations where ct might be leaked as error paths are
skipping the refcounted check and return immediately. In order to solve
it make sure that the check is always called.

Fixes: be102eb6a0 ("netfilter: nf_conncount: rework API to use sk_buff directly")
Signed-off-by: Fernando Fernandez Mancera <fmancera@suse.de>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-11 15:21:46 +01:00
Fernando Fernandez ManceraandGreg Kroah-Hartman 8286c02fe9 netfilter: nft_connlimit: update the count if add was skipped
[ Upstream commit 69894e5b4c ]

Connlimit expression can be used for all kind of packets and not only
for packets with connection state new. See this ruleset as example:

table ip filter {
        chain input {
                type filter hook input priority filter; policy accept;
                tcp dport 22 ct count over 4 counter
        }
}

Currently, if the connection count goes over the limit the counter will
count the packets. When a connection is closed, the connection count
won't decrement as it should because it is only updated for new
connections due to an optimization on __nf_conncount_add() that prevents
updating the list if the connection is duplicated.

To solve this problem, check whether the connection was skipped and if
so, update the list. Adjust count_tree() too so the same fix is applied
for xt_connlimit.

Fixes: 976afca1ce ("netfilter: nf_conncount: Early exit in nf_conncount_lookup() and cleanup")
Closes: https://lore.kernel.org/netfilter/trinity-85c72a88-d762-46c3-be97-36f10e5d9796-1761173693813@3c-app-mailcom-bs12/
Signed-off-by: Fernando Fernandez Mancera <fmancera@suse.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-11 15:21:34 +01:00
Fernando Fernandez ManceraandGreg Kroah-Hartman da9f247fb5 netfilter: nf_conncount: rework API to use sk_buff directly
[ Upstream commit be102eb6a0 ]

When using nf_conncount infrastructure for non-confirmed connections a
duplicated track is possible due to an optimization introduced since
commit d265929930 ("netfilter: nf_conncount: reduce unnecessary GC").

In order to fix this introduce a new conncount API that receives
directly an sk_buff struct.  It fetches the tuple and zone and the
corresponding ct from it. It comes with both existing conncount variants
nf_conncount_count_skb() and nf_conncount_add_skb(). In addition remove
the old API and adjust all the users to use the new one.

This way, for each sk_buff struct it is possible to check if there is a
ct present and already confirmed. If so, skip the add operation.

Fixes: d265929930 ("netfilter: nf_conncount: reduce unnecessary GC")
Signed-off-by: Fernando Fernandez Mancera <fmancera@suse.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-11 15:21:34 +01:00
Pablo Neira AyusoandGreg Kroah-Hartman 11b01b8ef1 netfilter: flowtable: check for maximum number of encapsulations in bridge vlan
[ Upstream commit 634f3853cc ]

Add a sanity check to skip path discovery if the maximum number of
encapsulation is reached. While at it, check for underflow too.

Fixes: 26267bf9bb ("netfilter: flowtable: bridge vlan hardware offload and switchdev")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-11 15:21:34 +01:00
Pablo Neira AyusoandGreg Kroah-Hartman 3f358a66a0 netfilter: nf_tables: reject duplicate device on updates
commit cf5fb87fcd upstream.

A chain/flowtable update with duplicated devices in the same batch is
possible. Unfortunately, netdev event path only removes the first
device that is found, leaving unregistered the hook of the duplicated
device.

Check if a duplicated device exists in the transaction batch, bail out
with EEXIST in such case.

WARNING is hit when unregistering the hook:

 [49042.221275] WARNING: CPU: 4 PID: 8425 at net/netfilter/core.c:340 nf_hook_entry_head+0xaa/0x150
 [49042.221375] CPU: 4 UID: 0 PID: 8425 Comm: nft Tainted: G S                  6.16.0+ #170 PREEMPT(full)
 [...]
 [49042.221382] RIP: 0010:nf_hook_entry_head+0xaa/0x150

Fixes: 78d9f48f7f ("netfilter: nf_tables: add devices to existing flowtable")
Fixes: b9703ed44f ("netfilter: nf_tables: support for adding new devices to an existing netdev chain")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-11-24 10:30:05 +01:00
Fernando Fernandez ManceraandGreg Kroah-Hartman 0028e0134c netfilter: nft_objref: validate objref and objrefmap expressions
[ Upstream commit f359b809d5 ]

Referencing a synproxy stateful object from OUTPUT hook causes kernel
crash due to infinite recursive calls:

BUG: TASK stack guard page was hit at 000000008bda5b8c (stack is 000000003ab1c4a5..00000000494d8b12)
[...]
Call Trace:
 __find_rr_leaf+0x99/0x230
 fib6_table_lookup+0x13b/0x2d0
 ip6_pol_route+0xa4/0x400
 fib6_rule_lookup+0x156/0x240
 ip6_route_output_flags+0xc6/0x150
 __nf_ip6_route+0x23/0x50
 synproxy_send_tcp_ipv6+0x106/0x200
 synproxy_send_client_synack_ipv6+0x1aa/0x1f0
 nft_synproxy_do_eval+0x263/0x310
 nft_do_chain+0x5a8/0x5f0 [nf_tables
 nft_do_chain_inet+0x98/0x110
 nf_hook_slow+0x43/0xc0
 __ip6_local_out+0xf0/0x170
 ip6_local_out+0x17/0x70
 synproxy_send_tcp_ipv6+0x1a2/0x200
 synproxy_send_client_synack_ipv6+0x1aa/0x1f0
[...]

Implement objref and objrefmap expression validate functions.

Currently, only NFT_OBJECT_SYNPROXY object type requires validation.
This will also handle a jump to a chain using a synproxy object from the
OUTPUT hook.

Now when trying to reference a synproxy object in the OUTPUT hook, nft
will produce the following error:

synproxy_crash.nft: Error: Could not process rule: Operation not supported
  synproxy name mysynproxy
  ^^^^^^^^^^^^^^^^^^^^^^^^

Fixes: ee394f96ad ("netfilter: nft_synproxy: add synproxy stateful object support")
Reported-by: Georg Pfuetzenreuter <georg.pfuetzenreuter@suse.com>
Closes: https://bugzilla.suse.com/1250237
Signed-off-by: Fernando Fernandez Mancera <fmancera@suse.de>
Reviewed-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-10-19 16:30:44 +02:00
Florian WestphalandGreg Kroah-Hartman df0ffc4b51 netfilter: nf_tables: drop unused 3rd argument from validate callback ops
[ Upstream commit eaf9b2c875 ]

Since commit a654de8fdc ("netfilter: nf_tables: fix chain dependency validation")
the validate() callback no longer needs the return pointer argument.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Stable-dep-of: f359b809d5 ("netfilter: nft_objref: validate objref and objrefmap expressions")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-10-19 16:30:44 +02:00
Slavin LiuandGreg Kroah-Hartman 8cbe2a21d8 ipvs: Defer ip_vs_ftp unregister during netns cleanup
[ Upstream commit 134121bfd9 ]

On the netns cleanup path, __ip_vs_ftp_exit() may unregister ip_vs_ftp
before connections with valid cp->app pointers are flushed, leading to a
use-after-free.

Fix this by introducing a global `exiting_module` flag, set to true in
ip_vs_ftp_exit() before unregistering the pernet subsystem. In
__ip_vs_ftp_exit(), skip ip_vs_ftp unregister if called during netns
cleanup (when exiting_module is false) and defer it to
__ip_vs_cleanup_batch(), which unregisters all apps after all connections
are flushed. If called during module exit, unregister ip_vs_ftp
immediately.

Fixes: 61b1ab4583 ("IPVS: netns, add basic init per netns.")
Suggested-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Slavin Liu <slavin452@gmail.com>
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-10-15 11:58:04 +02:00
Zhang TengfeiandGreg Kroah-Hartman 54f4da8629 ipvs: Use READ_ONCE/WRITE_ONCE for ipvs->enable
[ Upstream commit 944b6b216c ]

KCSAN reported a data-race on the `ipvs->enable` flag, which is
written in the control path and read concurrently from many other
contexts.

Following a suggestion by Julian, this patch fixes the race by
converting all accesses to use `WRITE_ONCE()/READ_ONCE()`.
This lightweight approach ensures atomic access and acts as a
compiler barrier, preventing unsafe optimizations where the flag
is checked in loops (e.g., in ip_vs_est.c).

Additionally, the `enable` checks in the fast-path hooks
(`ip_vs_in_hook`, `ip_vs_out_hook`, `ip_vs_forward_icmp`) are
removed. These are unnecessary since commit 857ca89711
("ipvs: register hooks only with services"). The `enable=0`
condition they check for can only occur in two rare and non-fatal
scenarios: 1) after hooks are registered but before the flag is set,
and 2) after hooks are unregistered on cleanup_net. In the worst
case, a single packet might be mishandled (e.g., dropped), which
does not lead to a system crash or data corruption. Adding a check
in the performance-critical fast-path to handle this harmless
condition is not a worthwhile trade-off.

Fixes: 857ca89711 ("ipvs: register hooks only with services")
Reported-by: syzbot+1651b5234028c294c339@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=1651b5234028c294c339
Suggested-by: Julian Anastasov <ja@ssi.bg>
Link: https://lore.kernel.org/lvs-devel/2189fc62-e51e-78c9-d1de-d35b8e3657e3@ssi.bg/
Signed-off-by: Zhang Tengfei <zhtfdev@gmail.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-10-15 11:58:00 +02:00
Zhen NiandGreg Kroah-Hartman a2e10d05f5 netfilter: ipset: Remove unused htable_bits in macro ahash_region
[ Upstream commit ba941796d7 ]

Since the ahash_region() macro was redefined to calculate the region
index solely from HTABLE_REGION_BITS, the htable_bits parameter became
unused.

Remove the unused htable_bits argument and its call sites, simplifying
the code without changing semantics.

Fixes: 8478a729c0 ("netfilter: ipset: fix region locking in hash types")
Signed-off-by: Zhen Ni <zhen.ni@easystack.cn>
Reviewed-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-10-15 11:58:00 +02:00
Phil SutterandGreg Kroah-Hartman 2acc8d3f0a netfilter: conntrack: helper: Replace -EEXIST by -EBUSY
[ Upstream commit 54416fd767 ]

The helper registration return value is passed-through by module_init
callbacks which modprobe confuses with the harmless -EEXIST returned
when trying to load an already loaded module.

Make sure modprobe fails so users notice their helper has not been
registered and won't work.

Suggested-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Fixes: 12f7a50533 ("netfilter: add user-space connection tracking helper infrastructure")
Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-09-09 18:56:21 +02:00
Florian WestphalandGreg Kroah-Hartman 30cf811058 netfilter: ctnetlink: fix refcount leak on table dump
[ Upstream commit de788b2e62 ]

There is a reference count leak in ctnetlink_dump_table():
      if (res < 0) {
                nf_conntrack_get(&ct->ct_general); // HERE
                cb->args[1] = (unsigned long)ct;
                ...

While its very unlikely, its possible that ct == last.
If this happens, then the refcount of ct was already incremented.
This 2nd increment is never undone.

This prevents the conntrack object from being released, which in turn
keeps prevents cnet->count from dropping back to 0.

This will then block the netns dismantle (or conntrack rmmod) as
nf_conntrack_cleanup_net_list() will wait forever.

This can be reproduced by running conntrack_resize.sh selftest in a loop.
It takes ~20 minutes for me on a preemptible kernel on average before
I see a runaway kworker spinning in nf_conntrack_cleanup_net_list.

One fix would to change this to:
        if (res < 0) {
		if (ct != last)
	                nf_conntrack_get(&ct->ct_general);

But this reference counting isn't needed in the first place.
We can just store a cookie value instead.

A followup patch will do the same for ctnetlink_exp_dump_table,
it looks to me as if this has the same problem and like
ctnetlink_dump_table, we only need a 'skip hint', not the actual
object so we can apply the same cookie strategy there as well.

Fixes: d205dc4079 ("[NETFILTER]: ctnetlink: fix deadlock in table dumping")
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>
2025-08-28 16:28:14 +02:00
Paul ChaignonandGreg Kroah-Hartman 4795bcafe9 bpf: Check netfilter ctx accesses are aligned
[ Upstream commit 9e6448f7b1 ]

Similarly to the previous patch fixing the flow_dissector ctx accesses,
nf_is_valid_access also doesn't check that ctx accesses are aligned.
Contrary to flow_dissector programs, netfilter programs don't have
context conversion. The unaligned ctx accesses are therefore allowed by
the verifier.

Fixes: fd9c663b9a ("bpf: minimal support for programs hooked into netfilter framework")
Signed-off-by: Paul Chaignon <paul.chaignon@gmail.com>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/853ae9ed5edaa5196e8472ff0f1bb1cc24059214.1754039605.git.paul.chaignon@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-08-15 12:08:57 +02:00
Florian WestphalandGreg Kroah-Hartman 58004aa21e netfilter: xt_nfacct: don't assume acct name is null-terminated
[ Upstream commit bf58e667af ]

BUG: KASAN: slab-out-of-bounds in .. lib/vsprintf.c:721
Read of size 1 at addr ffff88801eac95c8 by task syz-executor183/5851
[..]
 string+0x231/0x2b0 lib/vsprintf.c:721
 vsnprintf+0x739/0xf00 lib/vsprintf.c:2874
 [..]
 nfacct_mt_checkentry+0xd2/0xe0 net/netfilter/xt_nfacct.c:41
 xt_check_match+0x3d1/0xab0 net/netfilter/x_tables.c:523

nfnl_acct_find_get() handles non-null input, but the error
printk relied on its presence.

Reported-by: syzbot+4ff165b9251e4d295690@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=4ff165b9251e4d295690
Tested-by: syzbot+4ff165b9251e4d295690@syzkaller.appspotmail.com
Fixes: ceb98d03ea ("netfilter: xtables: add nfacct match to support extended accounting")
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>
2025-08-15 12:08:50 +02:00
Kuniyuki IwashimaandGreg Kroah-Hartman ee25024857 bpf: Disable migration in nf_hook_run_bpf().
[ Upstream commit 17ce3e5949 ]

syzbot reported that the netfilter bpf prog can be called without
migration disabled in xmit path.

Then the assertion in __bpf_prog_run() fails, triggering the splat
below. [0]

Let's use bpf_prog_run_pin_on_cpu() in nf_hook_run_bpf().

[0]:
BUG: assuming non migratable context at ./include/linux/filter.h:703
in_atomic(): 0, irqs_disabled(): 0, migration_disabled() 0 pid: 5829, name: sshd-session
3 locks held by sshd-session/5829:
 #0: ffff88807b4e4218 (sk_lock-AF_INET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1667 [inline]
 #0: ffff88807b4e4218 (sk_lock-AF_INET){+.+.}-{0:0}, at: tcp_sendmsg+0x20/0x50 net/ipv4/tcp.c:1395
 #1: ffffffff8e5c4e00 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #1: ffffffff8e5c4e00 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
 #1: ffffffff8e5c4e00 (rcu_read_lock){....}-{1:3}, at: __ip_queue_xmit+0x69/0x26c0 net/ipv4/ip_output.c:470
 #2: ffffffff8e5c4e00 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #2: ffffffff8e5c4e00 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
 #2: ffffffff8e5c4e00 (rcu_read_lock){....}-{1:3}, at: nf_hook+0xb2/0x680 include/linux/netfilter.h:241
CPU: 0 UID: 0 PID: 5829 Comm: sshd-session Not tainted 6.16.0-rc6-syzkaller-00002-g155a3c003e55 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x16c/0x1f0 lib/dump_stack.c:120
 __cant_migrate kernel/sched/core.c:8860 [inline]
 __cant_migrate+0x1c7/0x250 kernel/sched/core.c:8834
 __bpf_prog_run include/linux/filter.h:703 [inline]
 bpf_prog_run include/linux/filter.h:725 [inline]
 nf_hook_run_bpf+0x83/0x1e0 net/netfilter/nf_bpf_link.c:20
 nf_hook_entry_hookfn include/linux/netfilter.h:157 [inline]
 nf_hook_slow+0xbb/0x200 net/netfilter/core.c:623
 nf_hook+0x370/0x680 include/linux/netfilter.h:272
 NF_HOOK_COND include/linux/netfilter.h:305 [inline]
 ip_output+0x1bc/0x2a0 net/ipv4/ip_output.c:433
 dst_output include/net/dst.h:459 [inline]
 ip_local_out net/ipv4/ip_output.c:129 [inline]
 __ip_queue_xmit+0x1d7d/0x26c0 net/ipv4/ip_output.c:527
 __tcp_transmit_skb+0x2686/0x3e90 net/ipv4/tcp_output.c:1479
 tcp_transmit_skb net/ipv4/tcp_output.c:1497 [inline]
 tcp_write_xmit+0x1274/0x84e0 net/ipv4/tcp_output.c:2838
 __tcp_push_pending_frames+0xaf/0x390 net/ipv4/tcp_output.c:3021
 tcp_push+0x225/0x700 net/ipv4/tcp.c:759
 tcp_sendmsg_locked+0x1870/0x42b0 net/ipv4/tcp.c:1359
 tcp_sendmsg+0x2e/0x50 net/ipv4/tcp.c:1396
 inet_sendmsg+0xb9/0x140 net/ipv4/af_inet.c:851
 sock_sendmsg_nosec net/socket.c:712 [inline]
 __sock_sendmsg net/socket.c:727 [inline]
 sock_write_iter+0x4aa/0x5b0 net/socket.c:1131
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x6c7/0x1150 fs/read_write.c:686
 ksys_write+0x1f8/0x250 fs/read_write.c:738
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe7d365d407
Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP:

Fixes: fd9c663b9a ("bpf: minimal support for programs hooked into netfilter framework")
Reported-by: syzbot+40f772d37250b6d10efc@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/6879466d.a00a0220.3af5df.0022.GAE@google.com/
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Tested-by: syzbot+40f772d37250b6d10efc@syzkaller.appspotmail.com
Acked-by: Florian Westphal <fw@strlen.de>
Link: https://patch.msgid.link/20250722224041.112292-1-kuniyu@google.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-08-15 12:08:49 +02:00
Fedor PchelkinandGreg Kroah-Hartman 9ac58afb0c netfilter: nf_tables: adjust lockdep assertions handling
[ Upstream commit 8df1b40de7 ]

It's needed to check the return value of lockdep_commit_lock_is_held(),
otherwise there's no point in this assertion as it doesn't print any
debug information on itself.

Found by Linux Verification Center (linuxtesting.org) with Svace static
analysis tool.

Fixes: b04df3da1b ("netfilter: nf_tables: do not defer rule destruction via call_rcu")
Reported-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-08-15 12:08:47 +02:00
Phil SutterandGreg Kroah-Hartman b488bee5e9 netfilter: nf_tables: Drop dead code from fill_*_info routines
[ Upstream commit 8080357a8c ]

This practically reverts commit 28339b21a3 ("netfilter: nf_tables: do
not send complete notification of deletions"): The feature was never
effective, due to prior modification of 'event' variable the conditional
early return never happened.

User space also relies upon the current behaviour, so better reintroduce
the shortened deletion notifications once it is fixed.

Fixes: 28339b21a3 ("netfilter: nf_tables: do not send complete notification of deletions")
Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-08-15 12:08:47 +02:00
Florian WestphalandGreg Kroah-Hartman 76179961c4 netfilter: nf_conntrack: fix crash due to removal of uninitialised entry
[ Upstream commit 2d72afb340 ]

A crash in conntrack was reported while trying to unlink the conntrack
entry from the hash bucket list:
    [exception RIP: __nf_ct_delete_from_lists+172]
    [..]
 #7 [ff539b5a2b043aa0] nf_ct_delete at ffffffffc124d421 [nf_conntrack]
 #8 [ff539b5a2b043ad0] nf_ct_gc_expired at ffffffffc124d999 [nf_conntrack]
 #9 [ff539b5a2b043ae0] __nf_conntrack_find_get at ffffffffc124efbc [nf_conntrack]
    [..]

The nf_conn struct is marked as allocated from slab but appears to be in
a partially initialised state:

 ct hlist pointer is garbage; looks like the ct hash value
 (hence crash).
 ct->status is equal to IPS_CONFIRMED|IPS_DYING, which is expected
 ct->timeout is 30000 (=30s), which is unexpected.

Everything else looks like normal udp conntrack entry.  If we ignore
ct->status and pretend its 0, the entry matches those that are newly
allocated but not yet inserted into the hash:
  - ct hlist pointers are overloaded and store/cache the raw tuple hash
  - ct->timeout matches the relative time expected for a new udp flow
    rather than the absolute 'jiffies' value.

If it were not for the presence of IPS_CONFIRMED,
__nf_conntrack_find_get() would have skipped the entry.

Theory is that we did hit following race:

cpu x 			cpu y			cpu z
 found entry E		found entry E
 E is expired		<preemption>
 nf_ct_delete()
 return E to rcu slab
					init_conntrack
					E is re-inited,
					ct->status set to 0
					reply tuplehash hnnode.pprev
					stores hash value.

cpu y found E right before it was deleted on cpu x.
E is now re-inited on cpu z.  cpu y was preempted before
checking for expiry and/or confirm bit.

					->refcnt set to 1
					E now owned by skb
					->timeout set to 30000

If cpu y were to resume now, it would observe E as
expired but would skip E due to missing CONFIRMED bit.

					nf_conntrack_confirm gets called
					sets: ct->status |= CONFIRMED
					This is wrong: E is not yet added
					to hashtable.

cpu y resumes, it observes E as expired but CONFIRMED:
			<resumes>
			nf_ct_expired()
			 -> yes (ct->timeout is 30s)
			confirmed bit set.

cpu y will try to delete E from the hashtable:
			nf_ct_delete() -> set DYING bit
			__nf_ct_delete_from_lists

Even this scenario doesn't guarantee a crash:
cpu z still holds the table bucket lock(s) so y blocks:

			wait for spinlock held by z

					CONFIRMED is set but there is no
					guarantee ct will be added to hash:
					"chaintoolong" or "clash resolution"
					logic both skip the insert step.
					reply hnnode.pprev still stores the
					hash value.

					unlocks spinlock
					return NF_DROP
			<unblocks, then
			 crashes on hlist_nulls_del_rcu pprev>

In case CPU z does insert the entry into the hashtable, cpu y will unlink
E again right away but no crash occurs.

Without 'cpu y' race, 'garbage' hlist is of no consequence:
ct refcnt remains at 1, eventually skb will be free'd and E gets
destroyed via: nf_conntrack_put -> nf_conntrack_destroy -> nf_ct_destroy.

To resolve this, move the IPS_CONFIRMED assignment after the table
insertion but before the unlock.

Pablo points out that the confirm-bit-store could be reordered to happen
before hlist add resp. the timeout fixup, so switch to set_bit and
before_atomic memory barrier to prevent this.

It doesn't matter if other CPUs can observe a newly inserted entry right
before the CONFIRMED bit was set:

Such event cannot be distinguished from above "E is the old incarnation"
case: the entry will be skipped.

Also change nf_ct_should_gc() to first check the confirmed bit.

The gc sequence is:
 1. Check if entry has expired, if not skip to next entry
 2. Obtain a reference to the expired entry.
 3. Call nf_ct_should_gc() to double-check step 1.

nf_ct_should_gc() is thus called only for entries that already failed an
expiry check. After this patch, once the confirmed bit check passes
ct->timeout has been altered to reflect the absolute 'best before' date
instead of a relative time.  Step 3 will therefore not remove the entry.

Without this change to nf_ct_should_gc() we could still get this sequence:

 1. Check if entry has expired.
 2. Obtain a reference.
 3. Call nf_ct_should_gc() to double-check step 1:
    4 - entry is still observed as expired
    5 - meanwhile, ct->timeout is corrected to absolute value on other CPU
      and confirm bit gets set
    6 - confirm bit is seen
    7 - valid entry is removed again

First do check 6), then 4) so the gc expiry check always picks up either
confirmed bit unset (entry gets skipped) or expiry re-check failure for
re-inited conntrack objects.

This change cannot be backported to releases before 5.19. Without
commit 8a75a2c174 ("netfilter: conntrack: remove unconfirmed list")
|= IPS_CONFIRMED line cannot be moved without further changes.

Cc: Razvan Cojocaru <rzvncj@gmail.com>
Link: https://lore.kernel.org/netfilter-devel/20250627142758.25664-1-fw@strlen.de/
Link: https://lore.kernel.org/netfilter-devel/4239da15-83ff-4ca4-939d-faef283471bb@gmail.com/
Fixes: 1397af5bfd ("netfilter: conntrack: remove the percpu dying list")
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>
2025-07-24 08:53:19 +02:00
Florian WestphalandGreg Kroah-Hartman 1c7a023b0c netfilter: nf_nat: also check reverse tuple to obtain clashing entry
[ Upstream commit 50d9ce9679 ]

The logic added in the blamed commit was supposed to only omit nat source
port allocation if neither the existing nor the new entry are subject to
NAT.

However, its not enough to lookup the conntrack based on the proposed
tuple, we must also check the reverse direction.

Otherwise there are esoteric cases where the collision is in the reverse
direction because that colliding connection has a port rewrite, but the
new entry doesn't.  In this case, we only check the new entry and then
erronously conclude that no clash exists anymore.

 The existing (udp) tuple is:
  a:p -> b:P, with nat translation to s:P, i.e. pure daddr rewrite,
  reverse tuple in conntrack table is s:P -> a:p.

When another UDP packet is sent directly to s, i.e. a:p->s:P, this is
correctly detected as a colliding entry: tuple is taken by existing reply
tuple in reverse direction.

But the colliding conntrack is only searched for with unreversed
direction, and we can't find such entry matching a:p->s:P.

The incorrect conclusion is that the clashing entry has timed out and
that no port address translation is required.

Such conntrack will then be discarded at nf_confirm time because the
proposed reverse direction clashes with an existing mapping in the
conntrack table.

Search for the reverse tuple too, this will then check the NAT bits of
the colliding entry and triggers port reallocation.

Followp patch extends nft_nat.sh selftest to cover this scenario.

The IPS_SEQ_ADJUST change is also a bug fix:
Instead of checking for SEQ_ADJ this tested for SEEN_REPLY and ASSURED
by accident -- _BIT is only for use with the test_bit() API.

This bug has little consequence in practice, because the sequence number
adjustments are only useful for TCP which doesn't support clash resolution.

The existing test case (conntrack_reverse_clash.sh) exercise a race
condition path (parallel conntrack creation on different CPUs), so
the colliding entries have neither SEEN_REPLY nor ASSURED set.

Thanks to Yafang Shao and Shaun Brady for an initial investigation
of this bug.

Fixes: d8f84a9bc7 ("netfilter: nf_nat: don't try nat source port reallocation for reverse dir clash")
Closes: https://bugzilla.netfilter.org/show_bug.cgi?id=1795
Reported-by: Yafang Shao <laoar.shao@gmail.com>
Reported-by: Shaun Brady <brady.1345@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Tested-by: Yafang Shao <laoar.shao@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-19 15:28:34 +02:00
Florian WestphalandGreg Kroah-Hartman 39bab2d351 netfilter: nf_set_pipapo_avx2: fix initial map fill
[ Upstream commit ea77c397bf ]

If the first field doesn't cover the entire start map, then we must zero
out the remainder, else we leak those bits into the next match round map.

The early fix was incomplete and did only fix up the generic C
implementation.

A followup patch adds a test case to nft_concat_range.sh.

Fixes: 791a615b7a ("netfilter: nf_set_pipapo: fix initial map fill")
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-19 15:28:34 +02:00
Fernando Fernandez ManceraandGreg Kroah-Hartman 68b69b50df netfilter: nft_tunnel: fix geneve_opt dump
[ Upstream commit 22a9613de4 ]

When dumping a nft_tunnel with more than one geneve_opt configured the
netlink attribute hierarchy should be as follow:

 NFTA_TUNNEL_KEY_OPTS
 |
 |--NFTA_TUNNEL_KEY_OPTS_GENEVE
 |  |
 |  |--NFTA_TUNNEL_KEY_GENEVE_CLASS
 |  |--NFTA_TUNNEL_KEY_GENEVE_TYPE
 |  |--NFTA_TUNNEL_KEY_GENEVE_DATA
 |
 |--NFTA_TUNNEL_KEY_OPTS_GENEVE
 |  |
 |  |--NFTA_TUNNEL_KEY_GENEVE_CLASS
 |  |--NFTA_TUNNEL_KEY_GENEVE_TYPE
 |  |--NFTA_TUNNEL_KEY_GENEVE_DATA
 |
 |--NFTA_TUNNEL_KEY_OPTS_GENEVE
 ...

Otherwise, userspace tools won't be able to fetch the geneve options
configured correctly.

Fixes: 925d844696 ("netfilter: nft_tunnel: add support for geneve opts")
Signed-off-by: Fernando Fernandez Mancera <fmancera@suse.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-19 15:28:18 +02:00
Zhongqiu DuanandGreg Kroah-Hartman 5e4519d8cd netfilter: nft_quota: match correctly when the quota just depleted
[ Upstream commit bfe7cfb65c ]

The xt_quota compares skb length with remaining quota, but the nft_quota
compares it with consumed bytes.

The xt_quota can match consumed bytes up to quota at maximum. But the
nft_quota break match when consumed bytes equal to quota.

i.e., nft_quota match consumed bytes in [0, quota - 1], not [0, quota].

Fixes: 795595f68d ("netfilter: nft_quota: dump consumed quota")
Signed-off-by: Zhongqiu Duan <dzq.aishenghu0@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-19 15:28:13 +02:00
Nicolas BouchinetandGreg Kroah-Hartman 89947eea8f netfilter: conntrack: Bound nf_conntrack sysctl writes
[ Upstream commit 8b6861390f ]

nf_conntrack_max and nf_conntrack_expect_max sysctls were authorized to
be written any negative value, which would then be stored in the
unsigned int variables nf_conntrack_max and nf_ct_expect_max variables.

While the do_proc_dointvec_conv function is supposed to limit writing
handled by proc_dointvec proc_handler to INT_MAX. Such a negative value
being written in an unsigned int leads to a very high value, exceeding
this limit.

Moreover, the nf_conntrack_expect_max sysctl documentation specifies the
minimum value is 1.

The proc_handlers have thus been updated to proc_dointvec_minmax in
order to specify the following write bounds :

* Bound nf_conntrack_max sysctl writings between SYSCTL_ZERO
  and SYSCTL_INT_MAX.

* Bound nf_conntrack_expect_max sysctl writings between SYSCTL_ONE
  and SYSCTL_INT_MAX as defined in the sysctl documentation.

With this patch applied, sysctl writes outside the defined in the bound
will thus lead to a write error :

```
sysctl -w net.netfilter.nf_conntrack_expect_max=-1
sysctl: setting key "net.netfilter.nf_conntrack_expect_max": Invalid argument
```

Signed-off-by: Nicolas Bouchinet <nicolas.bouchinet@ssi.gouv.fr>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-04 14:42:00 +02:00
Jozsef KadlecsikandGreg Kroah-Hartman a3dfec4854 netfilter: ipset: fix region locking in hash types
[ Upstream commit 8478a729c0 ]

Region locking introduced in v5.6-rc4 contained three macros to handle
the region locks: ahash_bucket_start(), ahash_bucket_end() which gave
back the start and end hash bucket values belonging to a given region
lock and ahash_region() which should give back the region lock belonging
to a given hash bucket. The latter was incorrect which can lead to a
race condition between the garbage collector and adding new elements
when a hash type of set is defined with timeouts.

Fixes: f66ee0410b ("netfilter: ipset: Fix "INFO: rcu detected stall in hash_xxx" reports")
Reported-by: Kota Toda <kota.toda@gmo-cybersecurity.com>
Signed-off-by: Jozsef Kadlecsik <kadlec@netfilter.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-05-18 08:24:05 +02:00
Julian AnastasovandGreg Kroah-Hartman adbc8cc116 ipvs: fix uninit-value for saddr in do_output_route4
[ Upstream commit e34090d721 ]

syzbot reports for uninit-value for the saddr argument [1].
commit 4754957f04 ("ipvs: do not use random local source address for
tunnels") already implies that the input value of saddr
should be ignored but the code is still reading it which can prevent
to connect the route. Fix it by changing the argument to ret_saddr.

[1]
BUG: KMSAN: uninit-value in do_output_route4+0x42c/0x4d0 net/netfilter/ipvs/ip_vs_xmit.c:147
 do_output_route4+0x42c/0x4d0 net/netfilter/ipvs/ip_vs_xmit.c:147
 __ip_vs_get_out_rt+0x403/0x21d0 net/netfilter/ipvs/ip_vs_xmit.c:330
 ip_vs_tunnel_xmit+0x205/0x2380 net/netfilter/ipvs/ip_vs_xmit.c:1136
 ip_vs_in_hook+0x1aa5/0x35b0 net/netfilter/ipvs/ip_vs_core.c:2063
 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline]
 nf_hook_slow+0xf7/0x400 net/netfilter/core.c:626
 nf_hook include/linux/netfilter.h:269 [inline]
 __ip_local_out+0x758/0x7e0 net/ipv4/ip_output.c:118
 ip_local_out net/ipv4/ip_output.c:127 [inline]
 ip_send_skb+0x6a/0x3c0 net/ipv4/ip_output.c:1501
 udp_send_skb+0xfda/0x1b70 net/ipv4/udp.c:1195
 udp_sendmsg+0x2fe3/0x33c0 net/ipv4/udp.c:1483
 inet_sendmsg+0x1fc/0x280 net/ipv4/af_inet.c:851
 sock_sendmsg_nosec net/socket.c:712 [inline]
 __sock_sendmsg+0x267/0x380 net/socket.c:727
 ____sys_sendmsg+0x91b/0xda0 net/socket.c:2566
 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2620
 __sys_sendmmsg+0x41d/0x880 net/socket.c:2702
 __compat_sys_sendmmsg net/compat.c:360 [inline]
 __do_compat_sys_sendmmsg net/compat.c:367 [inline]
 __se_compat_sys_sendmmsg net/compat.c:364 [inline]
 __ia32_compat_sys_sendmmsg+0xc8/0x140 net/compat.c:364
 ia32_sys_call+0x3ffa/0x41f0 arch/x86/include/generated/asm/syscalls_32.h:346
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0xb0/0x110 arch/x86/entry/syscall_32.c:306
 do_fast_syscall_32+0x38/0x80 arch/x86/entry/syscall_32.c:331
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/syscall_32.c:369
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:4167 [inline]
 slab_alloc_node mm/slub.c:4210 [inline]
 __kmalloc_cache_noprof+0x8fa/0xe00 mm/slub.c:4367
 kmalloc_noprof include/linux/slab.h:905 [inline]
 ip_vs_dest_dst_alloc net/netfilter/ipvs/ip_vs_xmit.c:61 [inline]
 __ip_vs_get_out_rt+0x35d/0x21d0 net/netfilter/ipvs/ip_vs_xmit.c:323
 ip_vs_tunnel_xmit+0x205/0x2380 net/netfilter/ipvs/ip_vs_xmit.c:1136
 ip_vs_in_hook+0x1aa5/0x35b0 net/netfilter/ipvs/ip_vs_core.c:2063
 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline]
 nf_hook_slow+0xf7/0x400 net/netfilter/core.c:626
 nf_hook include/linux/netfilter.h:269 [inline]
 __ip_local_out+0x758/0x7e0 net/ipv4/ip_output.c:118
 ip_local_out net/ipv4/ip_output.c:127 [inline]
 ip_send_skb+0x6a/0x3c0 net/ipv4/ip_output.c:1501
 udp_send_skb+0xfda/0x1b70 net/ipv4/udp.c:1195
 udp_sendmsg+0x2fe3/0x33c0 net/ipv4/udp.c:1483
 inet_sendmsg+0x1fc/0x280 net/ipv4/af_inet.c:851
 sock_sendmsg_nosec net/socket.c:712 [inline]
 __sock_sendmsg+0x267/0x380 net/socket.c:727
 ____sys_sendmsg+0x91b/0xda0 net/socket.c:2566
 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2620
 __sys_sendmmsg+0x41d/0x880 net/socket.c:2702
 __compat_sys_sendmmsg net/compat.c:360 [inline]
 __do_compat_sys_sendmmsg net/compat.c:367 [inline]
 __se_compat_sys_sendmmsg net/compat.c:364 [inline]
 __ia32_compat_sys_sendmmsg+0xc8/0x140 net/compat.c:364
 ia32_sys_call+0x3ffa/0x41f0 arch/x86/include/generated/asm/syscalls_32.h:346
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0xb0/0x110 arch/x86/entry/syscall_32.c:306
 do_fast_syscall_32+0x38/0x80 arch/x86/entry/syscall_32.c:331
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/syscall_32.c:369
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

CPU: 0 UID: 0 PID: 22408 Comm: syz.4.5165 Not tainted 6.15.0-rc3-syzkaller-00019-gbc3372351d0c #0 PREEMPT(undef)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025

Reported-by: syzbot+04b9a82855c8aed20860@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/68138dfa.050a0220.14dd7d.0017.GAE@google.com/
Fixes: 4754957f04 ("ipvs: do not use random local source address for tunnels")
Signed-off-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>
2025-05-18 08:24:05 +02:00
Florian WestphalandGreg Kroah-Hartman 90cdd7e5a4 nft_set_pipapo: fix incorrect avx2 match of 5th field octet
[ Upstream commit e042ed950d ]

Given a set element like:

	icmpv6 . dead:beef:00ff::1

The value of 'ff' is irrelevant, any address will be matched
as long as the other octets are the same.

This is because of too-early register clobbering:
ymm7 is reloaded with new packet data (pkt[9])  but it still holds data
of an earlier load that wasn't processed yet.

The existing tests in nft_concat_range.sh selftests do exercise this code
path, but do not trigger incorrect matching due to the network prefix
limitation.

Fixes: 7400b06396 ("nft_set_pipapo: Introduce AVX2-based lookup implementation")
Reported-by: sontu mazumdar <sontu21@gmail.com>
Closes: https://lore.kernel.org/netfilter/CANgxkqwnMH7fXra+VUfODT-8+qFLgskq3set1cAzqqJaV4iEZg@mail.gmail.com/T/#t
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>
2025-04-25 10:45:09 +02:00
Lin MaandGreg Kroah-Hartman 5a2976cc4d net: fix geneve_opt length integer overflow
[ Upstream commit b27055a08a ]

struct geneve_opt uses 5 bit length for each single option, which
means every vary size option should be smaller than 128 bytes.

However, all current related Netlink policies cannot promise this
length condition and the attacker can exploit a exact 128-byte size
option to *fake* a zero length option and confuse the parsing logic,
further achieve heap out-of-bounds read.

One example crash log is like below:

[    3.905425] ==================================================================
[    3.905925] BUG: KASAN: slab-out-of-bounds in nla_put+0xa9/0xe0
[    3.906255] Read of size 124 at addr ffff888005f291cc by task poc/177
[    3.906646]
[    3.906775] CPU: 0 PID: 177 Comm: poc-oob-read Not tainted 6.1.132 #1
[    3.907131] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
[    3.907784] Call Trace:
[    3.907925]  <TASK>
[    3.908048]  dump_stack_lvl+0x44/0x5c
[    3.908258]  print_report+0x184/0x4be
[    3.909151]  kasan_report+0xc5/0x100
[    3.909539]  kasan_check_range+0xf3/0x1a0
[    3.909794]  memcpy+0x1f/0x60
[    3.909968]  nla_put+0xa9/0xe0
[    3.910147]  tunnel_key_dump+0x945/0xba0
[    3.911536]  tcf_action_dump_1+0x1c1/0x340
[    3.912436]  tcf_action_dump+0x101/0x180
[    3.912689]  tcf_exts_dump+0x164/0x1e0
[    3.912905]  fw_dump+0x18b/0x2d0
[    3.913483]  tcf_fill_node+0x2ee/0x460
[    3.914778]  tfilter_notify+0xf4/0x180
[    3.915208]  tc_new_tfilter+0xd51/0x10d0
[    3.918615]  rtnetlink_rcv_msg+0x4a2/0x560
[    3.919118]  netlink_rcv_skb+0xcd/0x200
[    3.919787]  netlink_unicast+0x395/0x530
[    3.921032]  netlink_sendmsg+0x3d0/0x6d0
[    3.921987]  __sock_sendmsg+0x99/0xa0
[    3.922220]  __sys_sendto+0x1b7/0x240
[    3.922682]  __x64_sys_sendto+0x72/0x90
[    3.922906]  do_syscall_64+0x5e/0x90
[    3.923814]  entry_SYSCALL_64_after_hwframe+0x6e/0xd8
[    3.924122] RIP: 0033:0x7e83eab84407
[    3.924331] Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 faf
[    3.925330] RSP: 002b:00007ffff505e370 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
[    3.925752] RAX: ffffffffffffffda RBX: 00007e83eaafa740 RCX: 00007e83eab84407
[    3.926173] RDX: 00000000000001a8 RSI: 00007ffff505e3c0 RDI: 0000000000000003
[    3.926587] RBP: 00007ffff505f460 R08: 00007e83eace1000 R09: 000000000000000c
[    3.926977] R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffff505f3c0
[    3.927367] R13: 00007ffff505f5c8 R14: 00007e83ead1b000 R15: 00005d4fbbe6dcb8

Fix these issues by enforing correct length condition in related
policies.

Fixes: 925d844696 ("netfilter: nft_tunnel: add support for geneve opts")
Fixes: 4ece477870 ("lwtunnel: add options setting and dumping for geneve")
Fixes: 0ed5269f9e ("net/sched: add tunnel option support to act_tunnel_key")
Fixes: 0a6e77784f ("net/sched: allow flower to match tunnel options")
Signed-off-by: Lin Ma <linma@zju.edu.cn>
Reviewed-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Link: https://patch.msgid.link/20250402165632.6958-1-linma@zju.edu.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-04-10 14:37:40 +02:00
Lin MaandGreg Kroah-Hartman 28d88ee1e1 netfilter: nft_tunnel: fix geneve_opt type confusion addition
[ Upstream commit 1b755d8eb1 ]

When handling multiple NFTA_TUNNEL_KEY_OPTS_GENEVE attributes, the
parsing logic should place every geneve_opt structure one by one
compactly. Hence, when deciding the next geneve_opt position, the
pointer addition should be in units of char *.

However, the current implementation erroneously does type conversion
before the addition, which will lead to heap out-of-bounds write.

[    6.989857] ==================================================================
[    6.990293] BUG: KASAN: slab-out-of-bounds in nft_tunnel_obj_init+0x977/0xa70
[    6.990725] Write of size 124 at addr ffff888005f18974 by task poc/178
[    6.991162]
[    6.991259] CPU: 0 PID: 178 Comm: poc-oob-write Not tainted 6.1.132 #1
[    6.991655] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
[    6.992281] Call Trace:
[    6.992423]  <TASK>
[    6.992586]  dump_stack_lvl+0x44/0x5c
[    6.992801]  print_report+0x184/0x4be
[    6.993790]  kasan_report+0xc5/0x100
[    6.994252]  kasan_check_range+0xf3/0x1a0
[    6.994486]  memcpy+0x38/0x60
[    6.994692]  nft_tunnel_obj_init+0x977/0xa70
[    6.995677]  nft_obj_init+0x10c/0x1b0
[    6.995891]  nf_tables_newobj+0x585/0x950
[    6.996922]  nfnetlink_rcv_batch+0xdf9/0x1020
[    6.998997]  nfnetlink_rcv+0x1df/0x220
[    6.999537]  netlink_unicast+0x395/0x530
[    7.000771]  netlink_sendmsg+0x3d0/0x6d0
[    7.001462]  __sock_sendmsg+0x99/0xa0
[    7.001707]  ____sys_sendmsg+0x409/0x450
[    7.002391]  ___sys_sendmsg+0xfd/0x170
[    7.003145]  __sys_sendmsg+0xea/0x170
[    7.004359]  do_syscall_64+0x5e/0x90
[    7.005817]  entry_SYSCALL_64_after_hwframe+0x6e/0xd8
[    7.006127] RIP: 0033:0x7ec756d4e407
[    7.006339] Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 faf
[    7.007364] RSP: 002b:00007ffed5d46760 EFLAGS: 00000202 ORIG_RAX: 000000000000002e
[    7.007827] RAX: ffffffffffffffda RBX: 00007ec756cc4740 RCX: 00007ec756d4e407
[    7.008223] RDX: 0000000000000000 RSI: 00007ffed5d467f0 RDI: 0000000000000003
[    7.008620] RBP: 00007ffed5d468a0 R08: 0000000000000000 R09: 0000000000000000
[    7.009039] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
[    7.009429] R13: 00007ffed5d478b0 R14: 00007ec756ee5000 R15: 00005cbd4e655cb8

Fix this bug with correct pointer addition and conversion in parse
and dump code.

Fixes: 925d844696 ("netfilter: nft_tunnel: add support for geneve opts")
Signed-off-by: Lin Ma <linma@zju.edu.cn>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-04-10 14:37:40 +02:00
Florian WestphalandGreg Kroah-Hartman 6134d1ea1e netfilter: nf_tables: don't unregister hook when table is dormant
[ Upstream commit 688c15017d ]

When nf_tables_updchain encounters an error, hook registration needs to
be rolled back.

This should only be done if the hook has been registered, which won't
happen when the table is flagged as dormant (inactive).

Just move the assignment into the registration block.

Reported-by: syzbot+53ed3a6440173ddbf499@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=53ed3a6440173ddbf499
Fixes: b9703ed44f ("netfilter: nf_tables: support for adding new devices to an existing netdev chain")
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>
2025-04-10 14:37:39 +02:00
Pablo Neira AyusoandGreg Kroah-Hartman 073b04796c netfilter: nft_set_hash: GC reaps elements with conncount for dynamic sets only
[ Upstream commit 9d74da1177 ]

conncount has its own GC handler which determines when to reap stale
elements, this is convenient for dynamic sets. However, this also reaps
non-dynamic sets with static configurations coming from control plane.
Always run connlimit gc handler but honor feedback to reap element if
this set is dynamic.

Fixes: 290180e244 ("netfilter: nf_tables: add connlimit support")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-04-10 14:37:39 +02:00
Sebastian Andrzej SiewiorandGreg Kroah-Hartman fa81cb19f5 netfilter: nft_counter: Use u64_stats_t for statistic.
commit 4a1d3acd6e upstream.

The nft_counter uses two s64 counters for statistics. Those two are
protected by a seqcount to ensure that the 64bit variable is always
properly seen during updates even on 32bit architectures where the store
is performed by two writes. A side effect is that the two counter (bytes
and packet) are written and read together in the same window.

This can be replaced with u64_stats_t. write_seqcount_begin()/ end() is
replaced with u64_stats_update_begin()/ end() and behaves the same way
as with seqcount_t on 32bit architectures. Additionally there is a
preempt_disable on PREEMPT_RT to ensure that a reader does not preempt a
writer.
On 64bit architectures the macros are removed and the reads happen
without any retries. This also means that the reader can observe one
counter (bytes) from before the update and the other counter (packets)
but that is okay since there is no requirement to have both counter from
the same update window.

Convert the statistic to u64_stats_t. There is one optimisation:
nft_counter_do_init() and nft_counter_clone() allocate a new per-CPU
counter and assign a value to it. During this assignment preemption is
disabled which is not needed because the counter is not yet exposed to
the system so there can not be another writer or reader. Therefore
disabling preemption is omitted and raw_cpu_ptr() is used to obtain a
pointer to a counter for the assignment.

Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Felix Moessbauer <felix.moessbauer@siemens.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-28 21:59:57 +01:00
Florian WestphalandGreg Kroah-Hartman a561c6a034 netfilter: nf_tables: allow clone callbacks to sleep
commit fa23e0d4b7 upstream.

Sven Auhagen reports transaction failures with following error:
  ./main.nft:13:1-26: Error: Could not process rule: Cannot allocate memory
  percpu: allocation failed, size=16 align=8 atomic=1, atomic alloc failed, no space left

This points to failing pcpu allocation with GFP_ATOMIC flag.
However, transactions happen from user context and are allowed to sleep.

One case where we can call into percpu allocator with GFP_ATOMIC is
nft_counter expression.

Normally this happens from control plane, so this could use GFP_KERNEL
instead.  But one use case, element insertion from packet path,
needs to use GFP_ATOMIC allocations (nft_dynset expression).

At this time, .clone callbacks always use GFP_ATOMIC for this reason.

Add gfp_t argument to the .clone function and pass GFP_KERNEL or
GFP_ATOMIC flag depending on context, this allows all clone memory
allocations to sleep for the normal (transaction) case.

Cc: Sven Auhagen <sven.auhagen@voleatech.de>
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>
2025-03-22 12:50:50 -07:00
Pablo Neira AyusoandGreg Kroah-Hartman f6de68e154 netfilter: nf_tables: bail out if stateful expression provides no .clone
commit 3c13725f43 upstream.

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.

Stable-dep-of: fa23e0d4b7 ("netfilter: nf_tables: allow clone callbacks to sleep")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-22 12:50:50 -07:00
Pablo Neira AyusoandGreg Kroah-Hartman 7fa2e2960f netfilter: nf_tables: use timestamp to check for set element timeout
commit 7395dfacff upstream.

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>
Signed-off-by: Jianqi Ren <jianqi.ren.cn@windriver.com>
Signed-off-by: He Zhe <zhe.he@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-22 12:50:50 -07:00
Alexey KashavkinandGreg Kroah-Hartman 181b68fa55 netfilter: nft_exthdr: fix offset with ipv4_find_option()
[ Upstream commit 6edd78af95 ]

There is an incorrect calculation in the offset variable which causes
the nft_skb_copy_to_reg() function to always return -EFAULT. Adding the
start variable is redundant. In the __ip_options_compile() function the
correct offset is specified when finding the function. There is no need
to add the size of the iphdr structure to the offset.

Fixes: dbb5281a1f ("netfilter: nf_tables: add support for matching IPv4 options")
Signed-off-by: Alexey Kashavkin <akashavkin@gmail.com>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-03-22 12:50:39 -07:00
Dan CarpenterandGreg Kroah-Hartman 1bd2a8bb1c ipvs: prevent integer overflow in do_ip_vs_get_ctl()
[ Upstream commit 80b78c39eb ]

The get->num_services variable is an unsigned int which is controlled by
the user.  The struct_size() function ensures that the size calculation
does not overflow an unsigned long, however, we are saving the result to
an int so the calculation can overflow.

Both "len" and "get->num_services" come from the user.  This check is
just a sanity check to help the user and ensure they are using the API
correctly.  An integer overflow here is not a big deal.  This has no
security impact.

Save the result from struct_size() type size_t to fix this integer
overflow bug.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-03-22 12:50:39 -07:00
Kohei EnjuandGreg Kroah-Hartman fda50302a1 netfilter: nf_conncount: Fully initialize struct nf_conncount_tuple in insert_tree()
[ Upstream commit d653bfeb07 ]

Since commit b36e4523d4 ("netfilter: nf_conncount: fix garbage
collection confirm race"), `cpu` and `jiffies32` were introduced to
the struct nf_conncount_tuple.

The commit made nf_conncount_add() initialize `conn->cpu` and
`conn->jiffies32` when allocating the struct.
In contrast, count_tree() was not changed to initialize them.

By commit 34848d5c89 ("netfilter: nf_conncount: Split insert and
traversal"), count_tree() was split and the relevant allocation
code now resides in insert_tree().
Initialize `conn->cpu` and `conn->jiffies32` in insert_tree().

BUG: KMSAN: uninit-value in find_or_evict net/netfilter/nf_conncount.c:117 [inline]
BUG: KMSAN: uninit-value in __nf_conncount_add+0xd9c/0x2850 net/netfilter/nf_conncount.c:143
 find_or_evict net/netfilter/nf_conncount.c:117 [inline]
 __nf_conncount_add+0xd9c/0x2850 net/netfilter/nf_conncount.c:143
 count_tree net/netfilter/nf_conncount.c:438 [inline]
 nf_conncount_count+0x82f/0x1e80 net/netfilter/nf_conncount.c:521
 connlimit_mt+0x7f6/0xbd0 net/netfilter/xt_connlimit.c:72
 __nft_match_eval net/netfilter/nft_compat.c:403 [inline]
 nft_match_eval+0x1a5/0x300 net/netfilter/nft_compat.c:433
 expr_call_ops_eval net/netfilter/nf_tables_core.c:240 [inline]
 nft_do_chain+0x426/0x2290 net/netfilter/nf_tables_core.c:288
 nft_do_chain_ipv4+0x1a5/0x230 net/netfilter/nft_chain_filter.c:23
 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline]
 nf_hook_slow+0xf4/0x400 net/netfilter/core.c:626
 nf_hook_slow_list+0x24d/0x860 net/netfilter/core.c:663
 NF_HOOK_LIST include/linux/netfilter.h:350 [inline]
 ip_sublist_rcv+0x17b7/0x17f0 net/ipv4/ip_input.c:633
 ip_list_rcv+0x9ef/0xa40 net/ipv4/ip_input.c:669
 __netif_receive_skb_list_ptype net/core/dev.c:5936 [inline]
 __netif_receive_skb_list_core+0x15c5/0x1670 net/core/dev.c:5983
 __netif_receive_skb_list net/core/dev.c:6035 [inline]
 netif_receive_skb_list_internal+0x1085/0x1700 net/core/dev.c:6126
 netif_receive_skb_list+0x5a/0x460 net/core/dev.c:6178
 xdp_recv_frames net/bpf/test_run.c:280 [inline]
 xdp_test_run_batch net/bpf/test_run.c:361 [inline]
 bpf_test_run_xdp_live+0x2e86/0x3480 net/bpf/test_run.c:390
 bpf_prog_test_run_xdp+0xf1d/0x1ae0 net/bpf/test_run.c:1316
 bpf_prog_test_run+0x5e5/0xa30 kernel/bpf/syscall.c:4407
 __sys_bpf+0x6aa/0xd90 kernel/bpf/syscall.c:5813
 __do_sys_bpf kernel/bpf/syscall.c:5902 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5900 [inline]
 __ia32_sys_bpf+0xa0/0xe0 kernel/bpf/syscall.c:5900
 ia32_sys_call+0x394d/0x4180 arch/x86/include/generated/asm/syscalls_32.h:358
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0xb0/0x110 arch/x86/entry/common.c:387
 do_fast_syscall_32+0x38/0x80 arch/x86/entry/common.c:412
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:450
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:4121 [inline]
 slab_alloc_node mm/slub.c:4164 [inline]
 kmem_cache_alloc_noprof+0x915/0xe10 mm/slub.c:4171
 insert_tree net/netfilter/nf_conncount.c:372 [inline]
 count_tree net/netfilter/nf_conncount.c:450 [inline]
 nf_conncount_count+0x1415/0x1e80 net/netfilter/nf_conncount.c:521
 connlimit_mt+0x7f6/0xbd0 net/netfilter/xt_connlimit.c:72
 __nft_match_eval net/netfilter/nft_compat.c:403 [inline]
 nft_match_eval+0x1a5/0x300 net/netfilter/nft_compat.c:433
 expr_call_ops_eval net/netfilter/nf_tables_core.c:240 [inline]
 nft_do_chain+0x426/0x2290 net/netfilter/nf_tables_core.c:288
 nft_do_chain_ipv4+0x1a5/0x230 net/netfilter/nft_chain_filter.c:23
 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline]
 nf_hook_slow+0xf4/0x400 net/netfilter/core.c:626
 nf_hook_slow_list+0x24d/0x860 net/netfilter/core.c:663
 NF_HOOK_LIST include/linux/netfilter.h:350 [inline]
 ip_sublist_rcv+0x17b7/0x17f0 net/ipv4/ip_input.c:633
 ip_list_rcv+0x9ef/0xa40 net/ipv4/ip_input.c:669
 __netif_receive_skb_list_ptype net/core/dev.c:5936 [inline]
 __netif_receive_skb_list_core+0x15c5/0x1670 net/core/dev.c:5983
 __netif_receive_skb_list net/core/dev.c:6035 [inline]
 netif_receive_skb_list_internal+0x1085/0x1700 net/core/dev.c:6126
 netif_receive_skb_list+0x5a/0x460 net/core/dev.c:6178
 xdp_recv_frames net/bpf/test_run.c:280 [inline]
 xdp_test_run_batch net/bpf/test_run.c:361 [inline]
 bpf_test_run_xdp_live+0x2e86/0x3480 net/bpf/test_run.c:390
 bpf_prog_test_run_xdp+0xf1d/0x1ae0 net/bpf/test_run.c:1316
 bpf_prog_test_run+0x5e5/0xa30 kernel/bpf/syscall.c:4407
 __sys_bpf+0x6aa/0xd90 kernel/bpf/syscall.c:5813
 __do_sys_bpf kernel/bpf/syscall.c:5902 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5900 [inline]
 __ia32_sys_bpf+0xa0/0xe0 kernel/bpf/syscall.c:5900
 ia32_sys_call+0x394d/0x4180 arch/x86/include/generated/asm/syscalls_32.h:358
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0xb0/0x110 arch/x86/entry/common.c:387
 do_fast_syscall_32+0x38/0x80 arch/x86/entry/common.c:412
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:450
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

Reported-by: syzbot+83fed965338b573115f7@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=83fed965338b573115f7
Fixes: b36e4523d4 ("netfilter: nf_conncount: fix garbage collection confirm race")
Signed-off-by: Kohei Enju <enjuk@amazon.com>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-03-22 12:50:39 -07:00
Nicklas Bo JensenandGreg Kroah-Hartman 0a9f0cfd2a netfilter: nf_conncount: garbage collection is not skipped when jiffies wrap around
[ Upstream commit df08c94baa ]

nf_conncount is supposed to skip garbage collection if it has already
run garbage collection in the same jiffy. Unfortunately, this is broken
when jiffies wrap around which this patch fixes.

The problem is that last_gc in the nf_conncount_list struct is an u32,
but jiffies is an unsigned long which is 8 bytes on my systems. When
those two are compared it only works until last_gc wraps around.

See bug report: https://bugzilla.netfilter.org/show_bug.cgi?id=1778
for more details.

Fixes: d265929930 ("netfilter: nf_conncount: reduce unnecessary GC")
Signed-off-by: Nicklas Bo Jensen <njensen@akamai.com>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-03-22 12:50:38 -07:00
Sebastian Andrzej SiewiorandGreg Kroah-Hartman 29bde9751c netfilter: nft_ct: Use __refcount_inc() for per-CPU nft_ct_pcpu_template.
[ Upstream commit 5cfe5612ca ]

nft_ct_pcpu_template is a per-CPU variable and relies on disabled BH for its
locking. The refcounter is read and if its value is set to one then the
refcounter is incremented and variable is used - otherwise it is already
in use and left untouched.

Without per-CPU locking in local_bh_disable() on PREEMPT_RT the
read-then-increment operation is not atomic and therefore racy.

This can be avoided by using unconditionally __refcount_inc() which will
increment counter and return the old value as an atomic operation.
In case the returned counter is not one, the variable is in use and we
need to decrement counter. Otherwise we can use it.

Use __refcount_inc() instead of read and a conditional increment.

Fixes: edee4f1e92 ("netfilter: nft_ct: add zone id set support")
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-03-22 12:50:37 -07:00
Pablo Neira AyusoandGreg Kroah-Hartman 82e491e085 netfilter: nf_tables: reject mismatching sum of field_len with set key length
commit 1b9335a800 upstream.

The field length description provides the length of each separated key
field in the concatenation, each field gets rounded up to 32-bits to
calculate the pipapo rule width from pipapo_init(). The set key length
provides the total size of the key aligned to 32-bits.

Register-based arithmetics still allows for combining mismatching set
key length and field length description, eg. set key length 10 and field
description [ 5, 4 ] leading to pipapo width of 12.

Cc: stable@vger.kernel.org
Fixes: 3ce67e3793 ("netfilter: nf_tables: do not allow mismatch field size and set key length")
Reported-by: Noam Rathaus <noamr@ssd-disclosure.com>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-08 09:52:35 +01:00
Florian WestphalandGreg Kroah-Hartman e3c1a0e4ba netfilter: nft_flow_offload: update tcp state flags under lock
[ Upstream commit 7a4b614063 ]

The conntrack entry is already public, there is a small chance that another
CPU is handling a packet in reply direction and racing with the tcp state
update.

Move this under ct spinlock.

This is done once, when ct is about to be offloaded, so this should
not result in a noticeable performance hit.

Fixes: 8437a6209f ("netfilter: nft_flow_offload: set liberal tracking mode for tcp")
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>
2025-02-08 09:52:03 +01:00
Pablo Neira AyusoandGreg Kroah-Hartman d9aaae892d netfilter: nf_tables: fix set size with rbtree backend
[ Upstream commit 8d738c1869 ]

The existing rbtree implementation uses singleton elements to represent
ranges, however, userspace provides a set size according to the number
of ranges in the set.

Adjust provided userspace set size to the number of singleton elements
in the kernel by multiplying the range by two.

Check if the no-match all-zero element is already in the set, in such
case release one slot in the set size.

Fixes: 0ed6389c48 ("netfilter: nf_tables: rename set implementations")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-02-08 09:52:03 +01:00
Florian WestphalandGreg Kroah-Hartman c80fcb6caa netfilter: nft_set_rbtree: prefer sync gc to async worker
[ Upstream commit 7d259f021a ]

There is no need for asynchronous garbage collection, rbtree inserts
can only happen from the netlink control plane.

We already perform on-demand gc on insertion, in the area of the
tree where the insertion takes place, but we don't do a full tree
walk there for performance reasons.

Do a full gc walk at the end of the transaction instead and
remove the async worker.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Stable-dep-of: 8d738c1869 ("netfilter: nf_tables: fix set size with rbtree backend")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-02-08 09:52:03 +01:00
Florian WestphalandGreg Kroah-Hartman b7e81ae386 netfilter: nft_set_rbtree: rename gc deactivate+erase function
[ Upstream commit 8079fc30f7 ]

Next patch adds a cllaer that doesn't hold the priv->write lock and
will need a similar function.

Rename the existing function to make it clear that it can only
be used for opportunistic gc during insertion.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Stable-dep-of: 8d738c1869 ("netfilter: nf_tables: fix set size with rbtree backend")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-02-08 09:52:03 +01:00
Florian WestphalandGreg Kroah-Hartman 6f8277b97a netfilter: nf_tables: de-constify set commit ops function argument
[ Upstream commit 2560016721 ]

The set backend using this already has to work around this via ugly
cast, don't spread this pattern.

Signed-off-by: Florian Westphal <fw@strlen.de>
Stable-dep-of: 8d738c1869 ("netfilter: nf_tables: fix set size with rbtree backend")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-02-08 09:52:03 +01:00
Pablo Neira AyusoandGreg Kroah-Hartman d5807dd132 netfilter: conntrack: clamp maximum hashtable size to INT_MAX
[ Upstream commit b541ba7d1f ]

Use INT_MAX as maximum size for the conntrack hashtable. Otherwise, it
is possible to hit WARN_ON_ONCE in __kvmalloc_node_noprof() when
resizing hashtable because __GFP_NOWARN is unset. See:

  0708a0afe2 ("mm: Consider __GFP_NOWARN flag for oversized kvmalloc() calls")

Note: hashtable resize is only possible from init_netns.

Fixes: 9cc1c73ad6 ("netfilter: conntrack: avoid integer overflow when resizing")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-01-17 13:36:15 +01:00