linux.git/include/net/netfilter, branch v6.17-rc2 Linux kernel source tree netfilter: nft_set: remove indirection from update API call 2025-07-25T16:40:23+00:00 Florian Westphal fw@strlen.de 2025-07-09T17:05:14+00:00 531e61312104d991459af73c838396db26aa3550 This stems from a time when sets and nft_dynset resided in different kernel modules. We can replace this with a direct call. We could even remove both ->update and ->delete, given its only supported by rhashtable, but on the off-chance we'll see runtime add/delete for other types or a new set type keep that as-is for now. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> 
This stems from a time when sets and nft_dynset resided in different kernel
modules.  We can replace this with a direct call.

We could even remove both ->update and ->delete, given its only
supported by rhashtable, but on the off-chance we'll see runtime
add/delete for other types or a new set type keep that as-is for now.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
netfilter: nft_set: remove one argument from lookup and update functions 2025-07-25T16:40:16+00:00 Florian Westphal fw@strlen.de 2025-07-09T17:05:13+00:00 17a20e09f086f2c574ac87f3cf6e14c4377f65f6 Return the extension pointer instead of passing it as a function argument to be filled in by the callee. As-is, whenever false is returned, the extension pointer is not used. For all set types, when true is returned, the extension pointer was set to the matching element. Only exception: nft_set_bitmap doesn't support extensions. Return a pointer to a static const empty element extension container. return false -> return NULL return true -> return the elements' extension pointer. This saves one function argument. Signed-off-by: Florian Westphal <fw@strlen.de> Reviewed-by: Stefano Brivio <sbrivio@redhat.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> 
Return the extension pointer instead of passing it as a function
argument to be filled in by the callee.

As-is, whenever false is returned, the extension pointer is not used.

For all set types, when true is returned, the extension pointer was set
to the matching element.

Only exception: nft_set_bitmap doesn't support extensions.
Return a pointer to a static const empty element extension container.

return false -> return NULL
return true -> return the elements' extension pointer.

This saves one function argument.

Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
netfilter: nf_tables: Remove unused nft_reduce_is_readonly() 2025-07-25T16:37:12+00:00 Yue Haibing yuehaibing@huawei.com 2025-06-24T01:48:18+00:00 bf6788742b8d6c73de441e088a71de7154f0d4aa Since commit 9e539c5b6d9c ("netfilter: nf_tables: disable expression reduction infra") this is unused. Signed-off-by: Yue Haibing <yuehaibing@huawei.com> Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> 
Since commit 9e539c5b6d9c ("netfilter: nf_tables: disable expression
reduction infra") this is unused.

Signed-off-by: Yue Haibing <yuehaibing@huawei.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
netfilter: load nf_log_syslog on enabling nf_conntrack_log_invalid 2025-07-25T16:35:41+00:00 Lance Yang lance.yang@linux.dev 2025-05-26T08:59:02+00:00 e89a68046687fe9913ce3bfad82f7ccbb65687e0 When no logger is registered, nf_conntrack_log_invalid fails to log invalid packets, leaving users unaware of actual invalid traffic. Improve this by loading nf_log_syslog, similar to how 'iptables -I FORWARD 1 -m conntrack --ctstate INVALID -j LOG' triggers it. Suggested-by: Florian Westphal <fw@strlen.de> Signed-off-by: Zi Li <zi.li@linux.dev> Signed-off-by: Lance Yang <lance.yang@linux.dev> Acked-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> 
When no logger is registered, nf_conntrack_log_invalid fails to log invalid
packets, leaving users unaware of actual invalid traffic. Improve this by
loading nf_log_syslog, similar to how 'iptables -I FORWARD 1 -m conntrack
--ctstate INVALID -j LOG' triggers it.

Suggested-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Zi Li <zi.li@linux.dev>
Signed-off-by: Lance Yang <lance.yang@linux.dev>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2025-07-17T18:00:33+00:00 Jakub Kicinski kuba@kernel.org 2025-07-17T17:56:56+00:00 af2d6148d2a159e1a0862bce5a2c88c1618a2b27 Cross-merge networking fixes after downstream PR (net-6.16-rc7). Conflicts: Documentation/netlink/specs/ovpn.yaml 880d43ca9aa4 ("netlink: specs: clean up spaces in brackets") af52020fc599 ("ovpn: reject unexpected netlink attributes") drivers/net/phy/phy_device.c a44312d58e78 ("net: phy: Don't register LEDs for genphy") f0f2b992d818 ("net: phy: Don't register LEDs for genphy") https://lore.kernel.org/20250710114926.7ec3a64f@kernel.org drivers/net/wireless/intel/iwlwifi/fw/regulatory.c drivers/net/wireless/intel/iwlwifi/mld/regulatory.c 5fde0fcbd760 ("wifi: iwlwifi: mask reserved bits in chan_state_active_bitmap") ea045a0de3b9 ("wifi: iwlwifi: add support for accepting raw DSM tables by firmware") net/ipv6/mcast.c ae3264a25a46 ("ipv6: mcast: Delay put pmc->idev in mld_del_delrec()") a8594c956cc9 ("ipv6: mcast: Avoid a duplicate pointer check in mld_del_delrec()") https://lore.kernel.org/8cc52891-3653-4b03-a45e-05464fe495cf@kernel.org No adjacent changes. Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Cross-merge networking fixes after downstream PR (net-6.16-rc7).

Conflicts:

Documentation/netlink/specs/ovpn.yaml
  880d43ca9aa4 ("netlink: specs: clean up spaces in brackets")
  af52020fc599 ("ovpn: reject unexpected netlink attributes")

drivers/net/phy/phy_device.c
  a44312d58e78 ("net: phy: Don't register LEDs for genphy")
  f0f2b992d818 ("net: phy: Don't register LEDs for genphy")
https://lore.kernel.org/20250710114926.7ec3a64f@kernel.org

drivers/net/wireless/intel/iwlwifi/fw/regulatory.c
drivers/net/wireless/intel/iwlwifi/mld/regulatory.c
  5fde0fcbd760 ("wifi: iwlwifi: mask reserved bits in chan_state_active_bitmap")
  ea045a0de3b9 ("wifi: iwlwifi: add support for accepting raw DSM tables by firmware")

net/ipv6/mcast.c
  ae3264a25a46 ("ipv6: mcast: Delay put pmc->idev in mld_del_delrec()")
  a8594c956cc9 ("ipv6: mcast: Avoid a duplicate pointer check in mld_del_delrec()")
https://lore.kernel.org/8cc52891-3653-4b03-a45e-05464fe495cf@kernel.org

No adjacent changes.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
netfilter: nf_conntrack: fix crash due to removal of uninitialised entry 2025-07-17T09:23:33+00:00 Florian Westphal fw@strlen.de 2025-07-16T18:39:14+00:00 2d72afb340657f03f7261e9243b44457a9228ac7 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 8a75a2c17410 ("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: 1397af5bfd7d ("netfilter: conntrack: remove the percpu dying list") Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> 
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 8a75a2c17410 ("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: 1397af5bfd7d ("netfilter: conntrack: remove the percpu dying list")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Revert "netfilter: nf_tables: Add notifications for hook changes" 2025-07-14T13:22:47+00:00 Phil Sutter phil@nwl.cc 2025-07-10T16:43:42+00:00 36a686c0784fcccdaa4f38b498a9ef0d42ea7cb8 This reverts commit 465b9ee0ee7bc268d7f261356afd6c4262e48d82. Such notifications fit better into core or nfnetlink_hook code, following the NFNL_MSG_HOOK_GET message format. Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> 
This reverts commit 465b9ee0ee7bc268d7f261356afd6c4262e48d82.

Such notifications fit better into core or nfnetlink_hook code,
following the NFNL_MSG_HOOK_GET message format.

Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2025-07-11T18:42:38+00:00 Jakub Kicinski kuba@kernel.org 2025-07-10T17:08:47+00:00 0cad34fb7c5d12a9b61862744e7130e9ce3bc58f Cross-merge networking fixes after downstream PR (net-6.16-rc6-2). No conflicts. Adjacent changes: drivers/net/wireless/mediatek/mt76/mt7925/mcu.c c701574c5412 ("wifi: mt76: mt7925: fix invalid array index in ssid assignment during hw scan") b3a431fe2e39 ("wifi: mt76: mt7925: fix off by one in mt7925_mcu_hw_scan()") drivers/net/wireless/mediatek/mt76/mt7996/mac.c 62da647a2b20 ("wifi: mt76: mt7996: Add MLO support to mt7996_tx_check_aggr()") dc66a129adf1 ("wifi: mt76: add a wrapper for wcid access with validation") drivers/net/wireless/mediatek/mt76/mt7996/main.c 3dd6f67c669c ("wifi: mt76: Move RCU section in mt7996_mcu_add_rate_ctrl()") 8989d8e90f5f ("wifi: mt76: mt7996: Do not set wcid.sta to 1 in mt7996_mac_sta_event()") net/mac80211/cfg.c 58fcb1b4287c ("wifi: mac80211: reject VHT opmode for unsupported channel widths") 037dc18ac3fb ("wifi: mac80211: add support for storing station S1G capabilities") Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Cross-merge networking fixes after downstream PR (net-6.16-rc6-2).

No conflicts.

Adjacent changes:

drivers/net/wireless/mediatek/mt76/mt7925/mcu.c
  c701574c5412 ("wifi: mt76: mt7925: fix invalid array index in ssid assignment during hw scan")
  b3a431fe2e39 ("wifi: mt76: mt7925: fix off by one in mt7925_mcu_hw_scan()")

drivers/net/wireless/mediatek/mt76/mt7996/mac.c
  62da647a2b20 ("wifi: mt76: mt7996: Add MLO support to mt7996_tx_check_aggr()")
  dc66a129adf1 ("wifi: mt76: add a wrapper for wcid access with validation")

drivers/net/wireless/mediatek/mt76/mt7996/main.c
  3dd6f67c669c ("wifi: mt76: Move RCU section in mt7996_mcu_add_rate_ctrl()")
  8989d8e90f5f ("wifi: mt76: mt7996: Do not set wcid.sta to 1 in mt7996_mac_sta_event()")

net/mac80211/cfg.c
  58fcb1b4287c ("wifi: mac80211: reject VHT opmode for unsupported channel widths")
  037dc18ac3fb ("wifi: mac80211: add support for storing station S1G capabilities")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
netfilter: flowtable: account for Ethernet header in nf_flow_pppoe_proto() 2025-07-11T00:12:28+00:00 Eric Dumazet edumazet@google.com 2025-07-07T12:45:17+00:00 18cdb3d982da8976b28d57691eb256ec5688fad2 syzbot found a potential access to uninit-value in nf_flow_pppoe_proto() Blamed commit forgot the Ethernet header. BUG: KMSAN: uninit-value in nf_flow_offload_inet_hook+0x7e4/0x940 net/netfilter/nf_flow_table_inet.c:27 nf_flow_offload_inet_hook+0x7e4/0x940 net/netfilter/nf_flow_table_inet.c:27 nf_hook_entry_hookfn include/linux/netfilter.h:157 [inline] nf_hook_slow+0xe1/0x3d0 net/netfilter/core.c:623 nf_hook_ingress include/linux/netfilter_netdev.h:34 [inline] nf_ingress net/core/dev.c:5742 [inline] __netif_receive_skb_core+0x4aff/0x70c0 net/core/dev.c:5837 __netif_receive_skb_one_core net/core/dev.c:5975 [inline] __netif_receive_skb+0xcc/0xac0 net/core/dev.c:6090 netif_receive_skb_internal net/core/dev.c:6176 [inline] netif_receive_skb+0x57/0x630 net/core/dev.c:6235 tun_rx_batched+0x1df/0x980 drivers/net/tun.c:1485 tun_get_user+0x4ee0/0x6b40 drivers/net/tun.c:1938 tun_chr_write_iter+0x3e9/0x5c0 drivers/net/tun.c:1984 new_sync_write fs/read_write.c:593 [inline] vfs_write+0xb4b/0x1580 fs/read_write.c:686 ksys_write fs/read_write.c:738 [inline] __do_sys_write fs/read_write.c:749 [inline] Reported-by: syzbot+bf6ed459397e307c3ad2@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/686bc073.a00a0220.c7b3.0086.GAE@google.com/T/#u Fixes: 87b3593bed18 ("netfilter: flowtable: validate pppoe header") Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Pablo Neira Ayuso <pablo@netfilter.org> Link: https://patch.msgid.link/20250707124517.614489-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
syzbot found a potential access to uninit-value in nf_flow_pppoe_proto()

Blamed commit forgot the Ethernet header.

BUG: KMSAN: uninit-value in nf_flow_offload_inet_hook+0x7e4/0x940 net/netfilter/nf_flow_table_inet.c:27
  nf_flow_offload_inet_hook+0x7e4/0x940 net/netfilter/nf_flow_table_inet.c:27
  nf_hook_entry_hookfn include/linux/netfilter.h:157 [inline]
  nf_hook_slow+0xe1/0x3d0 net/netfilter/core.c:623
  nf_hook_ingress include/linux/netfilter_netdev.h:34 [inline]
  nf_ingress net/core/dev.c:5742 [inline]
  __netif_receive_skb_core+0x4aff/0x70c0 net/core/dev.c:5837
  __netif_receive_skb_one_core net/core/dev.c:5975 [inline]
  __netif_receive_skb+0xcc/0xac0 net/core/dev.c:6090
  netif_receive_skb_internal net/core/dev.c:6176 [inline]
  netif_receive_skb+0x57/0x630 net/core/dev.c:6235
  tun_rx_batched+0x1df/0x980 drivers/net/tun.c:1485
  tun_get_user+0x4ee0/0x6b40 drivers/net/tun.c:1938
  tun_chr_write_iter+0x3e9/0x5c0 drivers/net/tun.c:1984
  new_sync_write fs/read_write.c:593 [inline]
  vfs_write+0xb4b/0x1580 fs/read_write.c:686
  ksys_write fs/read_write.c:738 [inline]
  __do_sys_write fs/read_write.c:749 [inline]

Reported-by: syzbot+bf6ed459397e307c3ad2@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/686bc073.a00a0220.c7b3.0086.GAE@google.com/T/#u
Fixes: 87b3593bed18 ("netfilter: flowtable: validate pppoe header")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Pablo Neira Ayuso <pablo@netfilter.org>
Link: https://patch.msgid.link/20250707124517.614489-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
netfilter: conntrack: remove DCCP protocol support 2025-07-03T11:51:39+00:00 Pablo Neira Ayuso pablo@netfilter.org 2025-05-22T14:52:23+00:00 fd72f265bb00d2dd2a3bbad7ec45520025e3a926 The DCCP socket family has now been removed from this tree, see: 8bb3212be4b4 ("Merge branch 'net-retire-dccp-socket'") Remove connection tracking and NAT support for this protocol, this should not pose a problem because no DCCP traffic is expected to be seen on the wire. As for the code for matching on dccp header for iptables and nftables, mark it as deprecated and keep it in place. Ruleset restoration is an atomic operation. Without dccp matching support, an astray match on dccp could break this operation leaving your computer with no policy in place, so let's follow a more conservative approach for matches. Add CONFIG_NFT_EXTHDR_DCCP which is set to 'n' by default to deprecate dccp extension support. Similarly, label CONFIG_NETFILTER_XT_MATCH_DCCP as deprecated too and also set it to 'n' by default. Code to match on DCCP protocol from ebtables also remains in place, this is just a few checks on IPPROTO_DCCP from _check() path which is exercised when ruleset is loaded. There is another use of IPPROTO_DCCP from the _check() path in the iptables multiport match. Another check for IPPROTO_DCCP from the packet in the reject target is also removed. So let's schedule removal of the dccp matching for a second stage, this should not interfer with the dccp retirement since this is only matching on the dccp header. Cc: "David S. Miller" <davem@davemloft.net> Cc: Eric Dumazet <edumazet@google.com> Cc: Jakub Kicinski <kuba@kernel.org> Cc: Paolo Abeni <pabeni@redhat.com> Cc: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> 
The DCCP socket family has now been removed from this tree, see:

  8bb3212be4b4 ("Merge branch 'net-retire-dccp-socket'")

Remove connection tracking and NAT support for this protocol, this
should not pose a problem because no DCCP traffic is expected to be seen
on the wire.

As for the code for matching on dccp header for iptables and nftables,
mark it as deprecated and keep it in place. Ruleset restoration is an
atomic operation. Without dccp matching support, an astray match on dccp
could break this operation leaving your computer with no policy in
place, so let's follow a more conservative approach for matches.

Add CONFIG_NFT_EXTHDR_DCCP which is set to 'n' by default to deprecate
dccp extension support. Similarly, label CONFIG_NETFILTER_XT_MATCH_DCCP
as deprecated too and also set it to 'n' by default.

Code to match on DCCP protocol from ebtables also remains in place, this
is just a few checks on IPPROTO_DCCP from _check() path which is
exercised when ruleset is loaded. There is another use of IPPROTO_DCCP
from the _check() path in the iptables multiport match. Another check
for IPPROTO_DCCP from the packet in the reject target is also removed.

So let's schedule removal of the dccp matching for a second stage, this
should not interfer with the dccp retirement since this is only matching
on the dccp header.

Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>