linux-stable.git/include/net/netfilter, branch v6.1.185

netfilter: nf_tables: Remove unused nft_reduce_is_readonly()

2026-08-23T12:18:24+00:00

[ Upstream commit bf6788742b8d6c73de441e088a71de7154f0d4aa ]

Since commit 9e539c5b6d9c ("netfilter: nf_tables: disable expression
reduction infra") this is unused.

Signed-off-by: Yue Haibing 
Reviewed-by: Simon Horman 
Signed-off-by: Pablo Neira Ayuso 
Stable-dep-of: d07955dd34ec ("netfilter: nft_fib: reject fib expression on the netdev egress hook")
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

netfilter: nf_tables: drop unused 3rd argument from validate callback ops

2026-08-23T12:18:24+00:00

[ Upstream commit eaf9b2c875ece22768b78aa38da8b232e5de021b ]

Since commit a654de8fdc18 ("netfilter: nf_tables: fix chain dependency validation")
the validate() callback no longer needs the return pointer argument.

Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso 
Stable-dep-of: d07955dd34ec ("netfilter: nft_fib: reject fib expression on the netdev egress hook")
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

netfilter: nf_tables: pass context structure to nft_parse_register_load

2026-08-23T12:18:24+00:00

[ Upstream commit 7ea0522ef81a335c2d3a0ab1c8a4fab9a23c4a03 ]

Mechanical transformation, no logical changes intended.

Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso 
Stable-dep-of: d07955dd34ec ("netfilter: nft_fib: reject fib expression on the netdev egress hook")
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

netfilter: nf_conntrack_expect: restore helper propagation via expectation

2026-08-19T15:16:10+00:00

[ Upstream commit dcb0f9aefdd604d36710fda53c25bd7cf4a3e37a ]

A recent series to fix expectations broke helper propagation via
expectation, this mechanism is used by the sip and h323 helper. This
also propagates the conntrack helper to expected connections. I changed
semantics of exp->helper which now tells us the actual helper that
created the expectation.

Add an explicit assign_helper field to expectations for this purpose
and update helpers to use it.

Restore this feature for userspace conntrack helper via ctnetlink
nfqueue integration so it is again possible to attach a helper to an
expectation, where it makes sense. This is not restored via ctnetlink
expectation creation as there is no client for such feature. Use the
expectation layer 4 protocol number for the helper lookup for
consistency.

Make sure the expectation using this helper propagation mechanism also
go away when the helper is unregistered.

Fixes: 9c42bc9db90a ("netfilter: nf_conntrack_expect: honor expectation helper field")
Fixes: 917b61fa2042 ("netfilter: ctnetlink: ignore explicit helper on new expectations")
Reported-by: Ilya Maximets 
Tested-by: Ilya Maximets 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin

netfilter: nf_queue: pin bridge device while NFQUEUE holds fake dst

2026-07-24T13:54:59+00:00

commit c9c9b37f8c5505224e8d206184df3bb668ee00cf upstream.

The br_netfilter fake rtable is embedded in struct net_bridge and is
attached to bridged packets with skb_dst_set_noref(). If such a packet is
queued to NFQUEUE, __nf_queue() upgrades that fake dst with
skb_dst_force().

At that point the queued skb can hold a real dst reference after bridge
teardown has started. The problem is not that every bridged packet needs
its own dst reference. The problem is that NFQUEUE can keep the bridge
private fake dst alive after unregister begins.

Fix this by keeping the bridge fake dst model unchanged and pinning the
bridge master device only while the packet sits in NFQUEUE. Record the
bridge device in nf_queue_entry when the queued skb carries a bridge fake
dst, take a device reference for the queue lifetime, and drop it when the
queue entry is freed.

Also make sure queued entries are reaped when that bridge device goes
down, and drop the redundant nf_bridge_info_exists() test from the fake
dst detection.

This keeps netdev_priv(br->dev) alive until verdict completion, so the
embedded fake rtable and its metrics backing storage cannot be freed out
from under dst_release(). It also avoids the constant refcount bump and
avoids using ipv4-specific dst helpers for IPv6 bridge traffic.

Fixes: 34666d467cbf ("netfilter: bridge: move br_netfilter out of the core")
Cc: stable@kernel.org
Reported-by: Yuan Tan 
Reported-by: Yifan Wu 
Reported-by: Juefei Pu 
Reported-by: Xin Liu 
Signed-off-by: Haoze Xie 
Signed-off-by: Ren Wei 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Greg Kroah-Hartman

netfilter: nf_tables: fix set size with rbtree backend

2026-07-04T11:41:27+00:00

[ Upstream commit 8d738c1869f611955d91d8d0fd0012d9ef207201 ]

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: 0ed6389c483d ("netfilter: nf_tables: rename set implementations")
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin 
[ Shivani: Modified to apply on 6.1.y ]
Signed-off-by: Shivani Agarwal 
Signed-off-by: Sasha Levin

netfilter: ctnetlink: ensure safe access to master conntrack

2026-06-19T11:37:13+00:00

[ Upstream commit bffcaad9afdfe45d7fc777397d3b83c1e3ebffe5 ]

Holding reference on the expectation is not sufficient, the master
conntrack object can just go away, making exp->master invalid.

To access exp->master safely:

- Grab the nf_conntrack_expect_lock, this gets serialized with
  clean_from_lists() which also holds this lock when the master
  conntrack goes away.

- Hold reference on master conntrack via nf_conntrack_find_get().
  Not so easy since the master tuple to look up for the master conntrack
  is not available in the existing problematic paths.

This patch goes for extending the nf_conntrack_expect_lock section
to address this issue for simplicity, in the cases that are described
below this is just slightly extending the lock section.

The add expectation command already holds a reference to the master
conntrack from ctnetlink_create_expect().

However, the delete expectation command needs to grab the spinlock
before looking up for the expectation. Expand the existing spinlock
section to address this to cover the expectation lookup. Note that,
the nf_ct_expect_iterate_net() calls already grabs the spinlock while
iterating over the expectation table, which is correct.

The get expectation command needs to grab the spinlock to ensure master
conntrack does not go away. This also expands the existing spinlock
section to cover the expectation lookup too. I needed to move the
netlink skb allocation out of the spinlock to keep it GFP_KERNEL.

For the expectation events, the IPEXP_DESTROY event is already delivered
under the spinlock, just move the delivery of IPEXP_NEW under the
spinlock too because the master conntrack event cache is reached through
exp->master.

While at it, add lockdep notations to help identify what codepaths need
to grab the spinlock.

Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso 
[ fix timer_delete -> del_timer in diff context lines since 8fa7292
("treewide: Switch/rename to timer_delete[_sync]()") landed in 6.15 ]
Signed-off-by: Mark Bundschuh 
Signed-off-by: Sasha Levin

netfilter: nf_conntrack: destroy stale expectfn expectations on unregister

2026-06-19T11:37:12+00:00

[ Upstream commit c3009418f9fa1dcb3eb86f4d8c92583537b5faa3 ]

NAT helpers such as nf_nat_h323 store a raw pointer to module text in
exp->expectfn (e.g. ip_nat_q931_expect). nf_ct_helper_expectfn_unregister()
only unlinks the callback descriptor and never walks the expectation table,
so an expectation pending at module removal survives with a dangling
exp->expectfn into freed module text.

When the expected connection arrives, init_conntrack() invokes
exp->expectfn(), now a stale pointer into the unloaded module. Reproduced
on a KASAN build by loading the H.323 helpers, creating a Q.931
expectation, unloading nf_nat_h323, then connecting to the expected port:

 Oops: int3: 0000 [#1] SMP KASAN NOPTI
 RIP: 0010:0xffffffffa06102d1
  init_conntrack.isra.0 (net/netfilter/nf_conntrack_core.c:1862)
  nf_conntrack_in (net/netfilter/nf_conntrack_core.c:2049)
  ipv4_conntrack_local (net/netfilter/nf_conntrack_proto.c:223)
  nf_hook_slow (net/netfilter/core.c:619)
  __ip_local_out (net/ipv4/ip_output.c:120)
  __tcp_transmit_skb (net/ipv4/tcp_output.c:1715)
  tcp_connect (net/ipv4/tcp_output.c:4374)
  tcp_v4_connect (net/ipv4/tcp_ipv4.c:345)
  __sys_connect (net/socket.c:2167)
 Modules linked in: nf_conntrack_h323 [last unloaded: nf_nat_h323]

Reaching the dangling state requires CAP_SYS_MODULE in the initial user
namespace to remove a NAT helper that still has live expectations, so this
is a robustness fix; leaving an expectation pointing at freed text is wrong
regardless.

Add nf_ct_helper_expectfn_destroy(), which walks the expectation table and
drops every expectation whose ->expectfn matches the descriptor being torn
down. Call it from each NAT helper's exit path after the existing RCU grace
period, so no expectation outlives the code it points at and no extra
synchronize_rcu() is introduced. With the fix, the same reproducer runs to
completion without the Oops.

Fixes: f587de0e2feb ("[NETFILTER]: nf_conntrack/nf_nat: add H.323 helper port")
Reported-by: Xiang Mei 
Assisted-by: Claude:claude-opus-4-8
Signed-off-by: Weiming Shi 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin

netfilter: nf_queue: hold bridge skb->dev while queued

2026-06-01T15:39:35+00:00

commit e196115ec330a18de415bdb9f5071aa9f08e53ce upstream.

br_pass_frame_up() rewrites skb->dev from the ingress port to the bridge
master before queueing bridge LOCAL_IN packets. NFQUEUE only holds
references on state.in/out and bridge physdevs, so a queued bridge
packet can retain a freed bridge master in skb->dev until reinjection.

When the verdict is reinjected later, br_netif_receive_skb() re-enters
the receive path with skb->dev still pointing at the freed bridge master,
triggering a use-after-free.

Store skb->dev in the queue entry, hold a reference on it for the queue
lifetime, and use the saved device when dropping queued packets during
NETDEV_DOWN handling.

Fixes: ac2863445686 ("netfilter: bridge: add nf_afinfo to enable queuing to userspace")
Cc: stable@kernel.org
Reported-by: Yuan Tan 
Reported-by: Yifan Wu 
Reported-by: Juefei Pu 
Reported-by: Xin Liu 
Signed-off-by: Haoze Xie 
Signed-off-by: Ren Wei 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Greg Kroah-Hartman

nf_tables: nft_dynset: fix possible stateful expression memleak in error path

2026-06-01T15:38:38+00:00

[ Upstream commit 0548a13b5a145b16e4da0628b5936baf35f51b43 ]

If cloning the second stateful expression in the element via GFP_ATOMIC
fails, then the first stateful expression remains in place without being
released.

   unreferenced object (percpu) 0x607b97e9cab8 (size 16):
     comm "softirq", pid 0, jiffies 4294931867
     hex dump (first 16 bytes on cpu 3):
       00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
     backtrace (crc 0):
       pcpu_alloc_noprof+0x453/0xd80
       nft_counter_clone+0x9c/0x190 [nf_tables]
       nft_expr_clone+0x8f/0x1b0 [nf_tables]
       nft_dynset_new+0x2cb/0x5f0 [nf_tables]
       nft_rhash_update+0x236/0x11c0 [nf_tables]
       nft_dynset_eval+0x11f/0x670 [nf_tables]
       nft_do_chain+0x253/0x1700 [nf_tables]
       nft_do_chain_ipv4+0x18d/0x270 [nf_tables]
       nf_hook_slow+0xaa/0x1e0
       ip_local_deliver+0x209/0x330

Fixes: 563125a73ac3 ("netfilter: nftables: generalize set extension to support for several expressions")
Reported-by: Gurpreet Shergill 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Florian Westphal 
[ Minor conflict resolved. ]
Signed-off-by: Li hongliang <1468888505@139.com>
Signed-off-by: Sasha Levin