linux-stable.git/net/netfilter, branch linux-6.14.y Linux kernel stable tree netfilter: conntrack: Bound nf_conntrack sysctl writes 2025-05-29T09:12:45+00:00 Nicolas Bouchinet nicolas.bouchinet@ssi.gouv.fr 2025-01-29T17:06:30+00:00 a135f2c70bf7382c74289ca9b42272667fc94f57 [ Upstream commit 8b6861390ffee6b8ed78b9395e3776c16fec6579 ] 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> 
[ Upstream commit 8b6861390ffee6b8ed78b9395e3776c16fec6579 ]

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>
netfilter: ipset: fix region locking in hash types 2025-05-18T06:25:58+00:00 Jozsef Kadlecsik kadlec@netfilter.org 2025-05-07T15:01:59+00:00 6e002ecc1c8cfdfc866b9104ab7888da54613e59 [ Upstream commit 8478a729c0462273188263136880480729e9efca ] 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: f66ee0410b1c ("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> 
[ Upstream commit 8478a729c0462273188263136880480729e9efca ]

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: f66ee0410b1c ("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>
ipvs: fix uninit-value for saddr in do_output_route4 2025-05-18T06:25:58+00:00 Julian Anastasov ja@ssi.bg 2025-05-02T22:01:18+00:00 a3a1b784791a3cbfc6e05c4d8a3c321ac5136e25 [ Upstream commit e34090d7214e0516eb8722aee295cb2507317c07 ] syzbot reports for uninit-value for the saddr argument [1]. commit 4754957f04f5 ("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: 4754957f04f5 ("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> 
[ Upstream commit e34090d7214e0516eb8722aee295cb2507317c07 ]

syzbot reports for uninit-value for the saddr argument [1].
commit 4754957f04f5 ("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: 4754957f04f5 ("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>
netfilter: conntrack: fix erronous removal of offload bit 2025-04-25T08:50:57+00:00 Florian Westphal fw@strlen.de 2025-04-15T13:53:48+00:00 cef8b1e5e11c747e4c439edc0011112078b6c997 [ Upstream commit d2d31ea8cd80b9830cdab624e94f9d41178fc99d ] The blamed commit exposes a possible issue with flow_offload_teardown(): We might remove the offload bit of a conntrack entry that has been offloaded again. 1. conntrack entry c1 is offloaded via flow f1 (f1->ct == c1). 2. f1 times out and is pushed back to slowpath, c1 offload bit is removed. Due to bug, f1 is not unlinked from rhashtable right away. 3. a new packet arrives for the flow and re-offload is triggered, i.e. f2->ct == c1. This is because lookup in flowtable skip entries with teardown bit set. 4. Next flowtable gc cycle finds f1 again 5. flow_offload_teardown() is called again for f1 and c1 offload bit is removed again, even though we have f2 referencing the same entry. This is harmless, but clearly not correct. Fix the bug that exposes this: set 'teardown = true' to have the gc callback unlink the flowtable entry from the table right away instead of the unintentional defer to the next round. Also prevent flow_offload_teardown() from fixing up the ct state more than once: We could also be called from the data path or a notifier, not only from the flowtable gc callback. NF_FLOW_TEARDOWN can never be unset, so we can use it as synchronization point: if we observe did not see a 0 -> 1 transition, then another CPU is already doing the ct state fixups for us. Fixes: 03428ca5cee9 ("netfilter: conntrack: rework offload nf_conn timeout extension logic") 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> 
[ Upstream commit d2d31ea8cd80b9830cdab624e94f9d41178fc99d ]

The blamed commit exposes a possible issue with flow_offload_teardown():
We might remove the offload bit of a conntrack entry that has been
offloaded again.

1. conntrack entry c1 is offloaded via flow f1 (f1->ct == c1).
2. f1 times out and is pushed back to slowpath, c1 offload bit is
   removed.  Due to bug, f1 is not unlinked from rhashtable right away.
3. a new packet arrives for the flow and re-offload is triggered, i.e.
   f2->ct == c1.  This is because lookup in flowtable skip entries with
   teardown bit set.
4. Next flowtable gc cycle finds f1 again
5. flow_offload_teardown() is called again for f1 and c1 offload bit is
   removed again, even though we have f2 referencing the same entry.

This is harmless, but clearly not correct.
Fix the bug that exposes this: set 'teardown = true' to have the gc
callback unlink the flowtable entry from the table right away instead of
the unintentional defer to the next round.

Also prevent flow_offload_teardown() from fixing up the ct state more than
once: We could also be called from the data path or a notifier, not only
from the flowtable gc callback.

NF_FLOW_TEARDOWN can never be unset, so we can use it as synchronization
point: if we observe did not see a 0 -> 1 transition, then another CPU
is already doing the ct state fixups for us.

Fixes: 03428ca5cee9 ("netfilter: conntrack: rework offload nf_conn timeout extension logic")
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>
nft_set_pipapo: fix incorrect avx2 match of 5th field octet 2025-04-20T08:22:21+00:00 Florian Westphal fw@strlen.de 2025-04-07T17:40:18+00:00 31968d1cb8f649ca9433d2f5429e38888a2c7e29 [ Upstream commit e042ed950d4e176379ba4c0722146cd96fb38aa2 ] 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: 7400b063969b ("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> 
[ Upstream commit e042ed950d4e176379ba4c0722146cd96fb38aa2 ]

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: 7400b063969b ("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>
net: fix geneve_opt length integer overflow 2025-04-10T12:44:41+00:00 Lin Ma linma@zju.edu.cn 2025-04-02T16:56:32+00:00 4d606069bdd3c76f8ab1f06796c97ef7f4746807 [ Upstream commit b27055a08ad4b415dcf15b63034f9cb236f7fb40 ] 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: 925d844696d9 ("netfilter: nft_tunnel: add support for geneve opts") Fixes: 4ece47787077 ("lwtunnel: add options setting and dumping for geneve") Fixes: 0ed5269f9e41 ("net/sched: add tunnel option support to act_tunnel_key") Fixes: 0a6e77784f49 ("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> 
[ Upstream commit b27055a08ad4b415dcf15b63034f9cb236f7fb40 ]

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: 925d844696d9 ("netfilter: nft_tunnel: add support for geneve opts")
Fixes: 4ece47787077 ("lwtunnel: add options setting and dumping for geneve")
Fixes: 0ed5269f9e41 ("net/sched: add tunnel option support to act_tunnel_key")
Fixes: 0a6e77784f49 ("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>
netfilter: nft_tunnel: fix geneve_opt type confusion addition 2025-04-10T12:44:41+00:00 Lin Ma linma@zju.edu.cn 2025-04-02T17:00:26+00:00 708e268acb3a446ad2a8a3d2e9bd41cc23660cd6 [ Upstream commit 1b755d8eb1ace3870789d48fbd94f386ad6e30be ] 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: 925d844696d9 ("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> 
[ Upstream commit 1b755d8eb1ace3870789d48fbd94f386ad6e30be ]

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: 925d844696d9 ("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>
netfilter: nf_tables: don't unregister hook when table is dormant 2025-04-10T12:44:40+00:00 Florian Westphal fw@strlen.de 2025-04-01T12:36:47+00:00 ce571eba07d54e3637bf334bc48376fbfa55defe [ Upstream commit 688c15017d5cd5aac882400782e7213d40dc3556 ] 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: b9703ed44ffb ("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> 
[ Upstream commit 688c15017d5cd5aac882400782e7213d40dc3556 ]

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: b9703ed44ffb ("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>
netfilter: nft_set_hash: GC reaps elements with conncount for dynamic sets only 2025-04-10T12:44:40+00:00 Pablo Neira Ayuso pablo@netfilter.org 2025-03-21T22:24:20+00:00 368043dcbf23e7c76a6b5047205df0b11c8d17e5 [ Upstream commit 9d74da1177c800eb3d51c13f9821b7b0683845a5 ] 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: 290180e2448c ("netfilter: nf_tables: add connlimit support") Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 9d74da1177c800eb3d51c13f9821b7b0683845a5 ]

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: 290180e2448c ("netfilter: nf_tables: add connlimit support")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
netfilter: nf_tables: Only use nf_skip_indirect_calls() when MITIGATION_RETPOLINE 2025-04-10T12:44:12+00:00 WangYuli wangyuli@uniontech.com 2025-03-19T14:01:47+00:00 4d19714355bc16151ebd6bf08627a3f0f6453c5c [ Upstream commit e3a4182edd1ae60e7e3539ff3b3784af9830d223 ] 1. MITIGATION_RETPOLINE is x86-only (defined in arch/x86/Kconfig), so no need to AND with CONFIG_X86 when checking if enabled. 2. Remove unused declaration of nf_skip_indirect_calls() when MITIGATION_RETPOLINE is disabled to avoid warnings. 3. Declare nf_skip_indirect_calls() and nf_skip_indirect_calls_enable() as inline when MITIGATION_RETPOLINE is enabled, as they are called only once and have simple logic. Fix follow error with clang-21 when W=1e: net/netfilter/nf_tables_core.c:39:20: error: unused function 'nf_skip_indirect_calls' [-Werror,-Wunused-function] 39 | static inline bool nf_skip_indirect_calls(void) { return false; } | ^~~~~~~~~~~~~~~~~~~~~~ 1 error generated. make[4]: *** [scripts/Makefile.build:207: net/netfilter/nf_tables_core.o] Error 1 make[3]: *** [scripts/Makefile.build:465: net/netfilter] Error 2 make[3]: *** Waiting for unfinished jobs.... Fixes: d8d760627855 ("netfilter: nf_tables: add static key to skip retpoline workarounds") Co-developed-by: Wentao Guan <guanwentao@uniontech.com> Signed-off-by: Wentao Guan <guanwentao@uniontech.com> Signed-off-by: WangYuli <wangyuli@uniontech.com> Acked-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit e3a4182edd1ae60e7e3539ff3b3784af9830d223 ]

1. MITIGATION_RETPOLINE is x86-only (defined in arch/x86/Kconfig),
so no need to AND with CONFIG_X86 when checking if enabled.

2. Remove unused declaration of nf_skip_indirect_calls() when
MITIGATION_RETPOLINE is disabled to avoid warnings.

3. Declare nf_skip_indirect_calls() and nf_skip_indirect_calls_enable()
as inline when MITIGATION_RETPOLINE is enabled, as they are called
only once and have simple logic.

Fix follow error with clang-21 when W=1e:
  net/netfilter/nf_tables_core.c:39:20: error: unused function 'nf_skip_indirect_calls' [-Werror,-Wunused-function]
     39 | static inline bool nf_skip_indirect_calls(void) { return false; }
        |                    ^~~~~~~~~~~~~~~~~~~~~~
  1 error generated.
  make[4]: *** [scripts/Makefile.build:207: net/netfilter/nf_tables_core.o] Error 1
  make[3]: *** [scripts/Makefile.build:465: net/netfilter] Error 2
  make[3]: *** Waiting for unfinished jobs....

Fixes: d8d760627855 ("netfilter: nf_tables: add static key to skip retpoline workarounds")
Co-developed-by: Wentao Guan <guanwentao@uniontech.com>
Signed-off-by: Wentao Guan <guanwentao@uniontech.com>
Signed-off-by: WangYuli <wangyuli@uniontech.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>