IPv4 and IPv6 input preserve an skb->sk association installed by
bpf_sk_assign() so that local delivery can use the selected socket under
RCU. Both address families can also prefetch a socket in UDP early demux.
In both paths (BPF and UDP early demux) a reference is not guaranteed to
be held on the socket.
When a multicast packet is not locally deliverable, IPv6 hands the
original skb to ip6_mr_input(). IPv4's ip_mr_input() similarly keeps the
original skb when local delivery is not needed. Either path can put the
skb on an unresolved multicast route queue or forward it after the
receive-side RCU section ends.
After the prefetched socket is destroyed, a later skb free invokes
sock_pfree() and dereferences the stale skb->sk. Orphan the skb before
each non-local multicast forwarding path. Local delivery retains the
original skb; the existing skb_clone() calls provide multicast forwarding
with a socket-free clone.
Fixes: cf7fbe660f ("bpf: Add socket assign support")
Fixes: 08842c43d0 ("udp: no longer touch sk->sk_refcnt in early demux")
Cc: stable@vger.kernel.org
Reported-by: Vega <vega@nebusec.ai>
Signed-off-by: Zhiling Zou <zhilinz@nebusec.ai>
Reported-by: Vega <vega@nebusec.ai>
Signed-off-by: Zhiling Zou <zhilinz@nebusec.ai>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/0c52eb3d7532aaf8bccf37e0f7c922143c639735.1786552223.git.zhilinz@nebusec.ai
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
IP tunnel devices derive their advertised needed_headroom from lower
output devices. A stack of user-created devices can make the derived
value larger than the 16-bit skb header offsets can represent. Once IP
output reserves it, skb head expansion can wrap those offsets.
The runtime transmit path already caps a growing needed_headroom at 512.
Apply the same cap when tunnel configuration publishes needed_headroom
derived from a lower output device.
Capping the advertised value is safe: IP tunnel transmit still expands
the skb when a packet needs more headroom. A nonsensical stacked
configuration can therefore incur an extra reallocation, but it cannot
publish an unbounded reservation to upper layers.
Fixes: 1a37e412a0 ("net: Use 16bits for *_headers fields of struct skbuff")
Cc: stable@vger.kernel.org
Reported-by: Vega <vega@nebusec.ai>
Signed-off-by: Zhiling Zou <zhilinz@nebusec.ai>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/ba04a1fd6bfae2377607fad5d8f80f7eb80fd4c4.1786542637.git.zhilinz@nebusec.ai
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
ip6gre_tnl_link_config_route() accumulates the lower device's hardware
header length into dev->hard_header_len whenever header_ops is set. This
is incorrect for both users of header_ops.
ip6gretap and ip6erspan have a fixed Ethernet hardware header length.
For an NBMA ip6gre tunnel, ip6gre_header() creates only the GRE header,
the optional FOU or GUE header, and the outer IPv6 header. The lower
device header is headroom needed later, not part of the tunnel device's
hardware header.
Keep the lower device header in needed_headroom. Set hard_header_len to
the tunnel header length only for ARPHRD_IP6GRE devices with header_ops,
and leave the fixed Ethernet header length unchanged for tap and erspan
devices.
Fixes: 832ba59649 ("net: ip6_gre: set dev->hard_header_len when using header_ops")
Cc: stable@vger.kernel.org
Suggested-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Zhiling Zou <zhilinz@nebusec.ai>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/64b46542bbe1701f07702aaa50273e2a87903db5.1786542637.git.zhilinz@nebusec.ai
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
ip6_tnl_xmit() may need to expand headroom before it can push the
outer IPv6 and optional encap headers. It currently does that with
skb_realloc_headroom(), copies skb->sk ownership, consumes the original
skb, and then continues processing with the replacement skb kept only in
its local variable.
That is safe only if the helper cannot fail afterwards. But this helper
still has post-reallocation error exits. collect_md tunnels reject
non-NONE encap after the replacement, and ip6_tnl_encap() can also fail
later. In those cases the helper returns an error to its callers while
the caller still only has the original skb pointer.
Both ip6_tnl_start_xmit() and the IPv6 GRE paths free the caller skb on
error, so they can end up freeing an skb that ip6_tnl_xmit() already
consumed.
Use skb_cow_head() instead. It provides the required headroom and
writability without privately replacing the caller-owned skb, so later
error returns cannot leave callers with a stale pointer.
The Ethernet users, ip6gretap and ip6erspan, clear IFF_TX_SKB_SHARING
and already call skb_cow_head() before entering ip6_tnl_xmit(). They do
not rely on the removed skb_shared() reallocation. This also makes the
IPv6 tunnel path consistent with ip_tunnel_xmit().
Fixes: 058214a4d1 ("ip6_tun: Add infrastructure for doing encapsulation")
Cc: stable@vger.kernel.org
Reported-by: Vega <vega@nebusec.ai>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Zhiling Zou <zhilinz@nebusec.ai>
Link: https://patch.msgid.link/30807a062ccc5c9c8a5ec2c5eb805ef279c50bdd.1786452593.git.zhilinz@nebusec.ai
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
ip6_finish_output2() caches a pointer to the IPv6 destination
address (daddr) before invoking lwtunnel_xmit(). The LWT-BPF
transmit path or other encapsulation operations within
lwtunnel_xmit() can reallocate the skb head, freeing the memory
that daddr points to. When lwtunnel_xmit() returns
LWTUNNEL_XMIT_CONTINUE, the function continues to use the stale
daddr pointer to compute the nexthop and to look up or create the
neighbour entry. This results in a use-after-free read, which can
leak sensitive kernel data, pollute the neighbour table with
arbitrary values, misdirect traffic, or crash the system.
Fix this by re-fetching the IPv6 header and the destination
address pointer after lwtunnel_xmit() returns
LWTUNNEL_XMIT_CONTINUE, ensuring that the subsequent nexthop
computation and neighbour lookup operate on valid memory.
Fixes: e415ed3a4b ("ipv6: use skb_expand_head in ip6_finish_output2")
Cc: stable@vger.kernel.org
Reported-by: Vega <vega@nebusec.ai>
Signed-off-by: Luxiao Xu <rakukuip@gmail.com>
Signed-off-by: Ren Wei <weir@nebusec.ai>
Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/4aa3f53bc44e79572c6dd2340ec7b68ef1a3d87d.1786516730.git.rakukuip@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
For IPv4 ERSPAN:
In erspan_xmit(), the driver clears IP_TUNNEL_SEQ_BIT (for version 0)
and IP_TUNNEL_KEY_BIT directly in the shared tunnel->parms.o_flags
structure. Since transmit paths can run locklessly and concurrently,
this leads to a data race.
Furthermore, modifying tunnel->parms.o_flags permanently alters the
tunnel configuration. To work around this, erspan_fill_info() (which
reports config to userspace) was setting IP_TUNNEL_KEY_BIT back. If
erspan_fill_info (running under RTNL) and erspan_xmit (running locklessly)
race, erspan_xmit might see IP_TUNNEL_KEY_BIT set when it shouldn't,
leading to GRE header corruption (injecting a key field into the ERSPAN
GRE header).
Fix this by:
1) Passing flags as an argument to __gre_xmit().
2) Using local stack flags in ipgre_xmit(), gre_tap_xmit(), and erspan_xmit()
to prevent TOCTOU data races with concurrent configuration updates,
and passing them to __gre_xmit().
3) Removing the racy modification of t->parms.o_flags in erspan_fill_info().
4) Forcing IP_TUNNEL_KEY_BIT in the reported flags for ERSPAN locally
in ipgre_fill_info().
For IPv6 ERSPAN:
ip6erspan_tunnel_xmit() was locklessly clearing IP_TUNNEL_KEY_BIT in
t->parms.o_flags even though it does not use these flags for building
the GRE header (it uses local flags). This permanently corrupts the
configuration and races with ip6gre_fill_info() which reads it.
Remove the redundant and racy modification.
This should remove false sharing in a fast path.
Add const qualifiers in ipgre_fill_info(), erspan_fill_info()
and ip6gre_fill_info() to clarify that these methods are not
supposed to write any live parameters.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260812142257.21283-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'nf-next-26-08-10' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next
Pablo Neira Ayuso says:
====================
Netfilter updates for net
This includes an enhancement to detect ct memleaks easier via
DEBUG_NET and flowtable preparation patches for IPv4 over IPV6
and vice-versa. This also includes a fix for the nft_ct custom
expectation support.
1) Add DEBUG_NET_WARN_ON_ONCE to nf_ct_set() to spot ct memleaks.
2) Pass struct net_device_path_ctx to dev_fill_forward_path() to
make it easier to pass more parameters to this function.
From Lorenzo Bianconi.
3) Add ether_type field to net_device_path context structucture.
4) Rename tun.l3_proto field to tun.inner_proto.
5) Rename ctx.tun.proto to ctx.tun.inner_proto.
6) Store ether_type in flowtable context.
7) Move IPv4 and IPv6 xmit path to a helper function.
8) Move encapsulation header parser out of the flowtable lookup
function.
9) Rework nft_ct custom expectation support to address a possible
reallocation of ct extension area while expectation list also
contains expectations. Move datapath to a ct helper to fix it.
10) Ensure timeout is always lowered for the non-closing RST case
in the TCP connection tracking.
11) Bail out when inserting already dead expectation, this should
not ever happen, hence report it via DEBUG_NET.
12) Comestic updates for improving the conntrack selftest dump and
flush userspace program, from Qingshuang Fu.
* tag 'nf-next-26-08-10' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next:
selftests: netfilter: conntrack_dump_flush: remove unused variables and fix typo
netfilter: nf_conntrack_expect: bail out on insert dead expectations
netfilter: conntrack: always lower timeout for non-closing RST packets
netfilter: nft_ct: move custom expectation support to helper
netfilter: flowtable: detach layer 2 encapsulation parser from lookup
netfilter: flowtable: move ipv4 and ipv6 xmit path to function
netfilter: flowtable: store ethertype in flowtable context
netfilter: flowtable: rename ctx.tun.proto to ctx.tun.inner_proto
netfilter: flowtable: rename tun.l3_proto to tun.inner_proto
net: netfilter: add ether_type to net_device_path_ctx and use it
net: pass net_device_path_ctx to dev_fill_forward_path()
netfilter: add DEBUG_NET_WARN_ON_ONCE to skb_set_nfct()
====================
Link: https://patch.msgid.link/20260810194015.932627-1-pablo@netfilter.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Add duplication helpers in the cases where the ctl_table array elements
are modified after duplication. Helpers return a ctl_table as const
pointer allowing the const qualification of the static global ctl_table
array.
Signed-off-by: Joel Granados <joel.granados@kernel.org>
Link: https://patch.msgid.link/20260810-jag-net_const_qualify-v4-3-77e888237c69@kernel.org
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Const qualify clt_table arrays in the net directory that always pass a
memory duplicate to sysctl register. The template would then be in
.rodata and the kmemdup'ed array would be outside.
Signed-off-by: Joel Granados <joel.granados@kernel.org>
Link: https://patch.msgid.link/20260810-jag-net_const_qualify-v4-2-77e888237c69@kernel.org
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Move the body of inet6_rt_notify() to __inet6_rt_notify() and give it
the deletion reason. inet6_rt_notify() keeps its prototype, so the
route addition path does not change.
Add inet6_rt_del_notify() and call it from fib6_del_route().
RTA_DEL_REASON now reaches user space on RTM_DELROUTE for routes the
kernel deleted on its own.
Signed-off-by: Yuyang Huang <sigefriedhyy@gmail.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260808005642.26901-7-sigefriedhyy@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Emit RTA_DEL_REASON from rt6_fill_node() when the deletion reason is
not RT_DEL_REASON_UNSPEC, and reserve room for it in
rt6_nlmsg_size().
Every caller still passes RT_DEL_REASON_UNSPEC.
Signed-off-by: Yuyang Huang <sigefriedhyy@gmail.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260808005642.26901-6-sigefriedhyy@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Add the deletion reason to rt6_fill_node() so that it can report it to
user space. All callers pass RT_DEL_REASON_UNSPEC for now.
Signed-off-by: Yuyang Huang <sigefriedhyy@gmail.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260808005642.26901-5-sigefriedhyy@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Record why the kernel deletes an IPv6 route on its own:
- RT_DEL_REASON_EXPIRED for routes reaped by the FIB6 garbage
collector after their RTF_EXPIRES lifetime ran out.
- RT_DEL_REASON_RA_WITHDRAWN for default routes, prefix routes and
RFC 4191 route information routes withdrawn by a zero-lifetime
Router Advertisement.
Deleting a default route because its metric changed is not a
withdrawal, so it keeps RT_DEL_REASON_UNSPEC.
Signed-off-by: Yuyang Huang <sigefriedhyy@gmail.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260808005642.26901-4-sigefriedhyy@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Pass the deletion reason from ip6_del_rt_reason() down through
__ip6_del_rt(), fib6_del() and into fib6_del_route(). All existing
callers pass RT_DEL_REASON_UNSPEC.
fib6_del_route() ignores the reason until the notification path learns
to report it.
Signed-off-by: Yuyang Huang <sigefriedhyy@gmail.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260808005642.26901-3-sigefriedhyy@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Add RTA_DEL_REASON and enum rt_del_reason to the rtnetlink uAPI, and
add ip6_del_rt_reason(), which takes the reason a route is being
deleted. It has no skip_notify argument: a caller that records a
deletion reason wants the notification that carries it.
The reason is unused for now. Subsequent patches propagate it to the
deletion path and report it on RTM_DELROUTE.
Signed-off-by: Yuyang Huang <sigefriedhyy@gmail.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260808005642.26901-2-sigefriedhyy@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
This field refers to the inner protocol that is encapsulated by the
tunnel header, just a comestic change. No functional changes are
expected.
Acked-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Add an ether_type field to struct net_device_path_ctx to reject IPv4
over IPv6 and vice-versa, this is currently not support. Otherwise,
incorrect dst_entry family can be reached from datapath.
Acked-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Replace the manual ND option parsing loop in br_nd_send() with
ndisc_parse_options(), which provides proper validation and avoids the
class of bugs that were fixed by commit 53fc685243 ("bridge: Avoid
infinite loop when suppressing NS messages with invalid options") and
commit 850837965a ("bridge: br_nd_send: validate ND option lengths").
Use ndisc_opt_addr_data() to extract the source link-layer address
from the parsed options, which correctly validates the option length
for the underlying device type.
Export ndisc_parse_options() so that it can be resolved from the bridge
when it is built as a module (CONFIG_BRIDGE=m); otherwise modpost fails
with an undefined symbol.
Reviewed-by: Petr Machata <petrm@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Danielle Ratson <danieller@nvidia.com>
Link: https://patch.msgid.link/20260803112505.613873-6-danieller@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Add ndisc_check_ns_na(), a standalone NS/NA packet validator modeled
after ipv6_mc_check_mld(). It performs the RFC 4861 section 7.1.1
(Neighbor Solicitation) and 7.1.2 (Neighbor Advertisement) mandatory
checks that are relevant for software operating at the bridge level,
where packets bypass the normal IPv6 stack path:
- Hop Limit must be 255 (packet was not forwarded by a router)
- ICMPv6 checksum is valid
- ICMP Code is 0
- ICMP length is at least 24 octets (sizeof(struct nd_msg))
- Target Address must not be a multicast address
- All included options have a length that is greater than zero
- NS/DAD: destination must be a solicited-node multicast address
- NS/DAD: no Source Link-Layer Address option when source is unspecified
- NA: Solicited flag must be 0 when IP Destination is multicast
On success the function sets the skb transport header and returns 0,
matching the convention of ipv6_mc_check_mld().
Reviewed-by: Petr Machata <petrm@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Danielle Ratson <danieller@nvidia.com>
Link: https://patch.msgid.link/20260803112505.613873-3-danieller@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
ip6ip6_err() clones an outer IPv6 ICMP error skb, pulls it to the
quoted inner IPv6 packet, and then passes the clone to icmpv6_send().
The clone still carries the outer packet's inet6_skb_parm in skb->cb.
If the outer packet had a Home Address Option, IP6CB(skb2)->dsthao
remains non-zero after skb_pull(). icmpv6_send() later calls
mip6_addr_swap(), which uses that stale dsthao offset against the quoted
inner packet. A malformed inner destination-options header can then make
the HAO lookup and address swap run past the end of the quoted packet
and corrupt skb_shared_info.
Clear skb2->cb[] before pulling the quoted inner IPv6 packet so the
reply path does not reuse metadata left by the outer IPv6 stack.
Fixes: e490d1d85c ("[IPV6] IP6TUNNEL: Split out generic routine in ip6ip6_err().")
Cc: stable@vger.kernel.org
Reported-by: Vega <vega@nebusec.ai>
Signed-off-by: Zhiling Zou <zhilinz@nebusec.ai>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/fe1a5e765fbca88d69391887f0ed26a19e3e4d39.1785736562.git.zhilinz@nebusec.ai
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'nf-next-26-07-31' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next
Pablo Neira Ayuso says:
====================
Netfilter updates for net-next
The following patchset contains Netfilter updates for net-next:
1) Update conncount to use the original tuple after ct lookup to ensure
consistent counting, from Fernando F. Mancera.
2) Remove redundant net_device field in info structure that helps
parse the flowtable path discovery.
3) Move net_device to flowtable check to the flowtable discovery
path parser. This is preparation work to pass the tunnel dst_entry
via .fill_forward_path.
4) Update DSA .fill_forward_path to break at the user DSA, since
the conduit DSA is not used in the datapath. This slighly simplifies
the flowtable path discovery parser.
5) Do not advance index in the path stack prematurely, otherwise
it points to uninitialized slots on error. Not an issue currently
but it could be once tunnel dst_entry is passed via .fill_forward_path.
6) Pass the tunnel dst_entry via dev_fill_forward_path().
7) Update ipip and ip6ip6 tunnels to pass the dst_entry through
dev_fill_forward_path().
8) Call skb_valid_dst() before accessing skb_dst() to ensure dst_entry
is not a template.
9) Use UNACK timeout when RST packet does not match the expected
window while in ESTABLISHED state, the existing approach the CLOSE
state timeout which is only 10 seconds. Adopt a more conservative
timeout by default for this case.
* tag 'nf-next-26-07-31' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next:
netfilter: conntrack: tcp: use UNACK timeout for non-closing RST packets
netfilter: nf_tables: call skb_valid_dst() before skb_dst()
netfilter: flowtable: release tunnel route on error when building forward path
net: pass dst via net_device_path in dev_fill_forward_path()
net: do not advance stack index from dev_fwd_path()
net: dsa: stop at the user device in .fill_forward_path
netfilter: flowtable: consolidate flowtable device check
netfilter: flowtable: consolidate net_device field in nft_forward_info struct
netfilter: conncount: normalize tuple and zone on successful ct lookup
====================
Link: https://patch.msgid.link/20260731153402.851224-1-pablo@netfilter.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Convert do_rawv6_getsockopt to the new sockopt_t model, mirroring what
we have in ipv4. The overall goal is to move these callbacks gradually
from __user points to use sockopt_t, and this part touches
do_rawv6_getsockopt.
No functional change.
Reviewed-by: Joe Damato <joe@dama.to>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260729-getsockopt_phase4-v4-2-c44576757c17@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
do_rawv6_getsockopt() takes a level argument but never uses it; the
level dispatch is handled by the caller, rawv6_getsockopt(). Drop it,
matching ipv4's do_raw_getsockopt().
No functional change.
Reviewed-by: Joe Damato <joe@dama.to>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260729-getsockopt_phase4-v4-1-c44576757c17@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
rt6_route_rcv() validates the Route Information option (RFC 4191) length
against the prefix length, but both checks are off by one.
rinfo->length is the ND option length in units of 8 octets and it
*includes* the 8-byte option header, so an option carrying N bytes of
prefix has length == 1 + N/8. RFC 4191 section 2.3 requires length 3
when Prefix Length is greater than 64, and 2 or 3 when it is greater
than 0. The code accepts length >= 2 and length >= 1 respectively.
ipv6_addr_prefix() then copies prefix_len/8 bytes out of rinfo->prefix,
so a Router Advertisement with (prefix_len=128, length=2) or
(prefix_len=64, length=1) makes the kernel read up to 8 bytes past the
end of the option. Those bytes end up in the prefix of the route that
gets installed, so they are visible to userspace:
# RA with a Route Information option (prefix_len=128, length=2)
# followed by a source link-layer address option, 01 01 de ad be ef ca fe
$ ip -6 route show
2001:db8:dead:beef:101:dead:beef:cafe via fe80::1234 dev veth0 proto ra
^^^^^^^^^^^^^^^^^^ the next option, read out of bounds
When the Route Information option is the last one in the packet, those
eight bytes come from the skb tail room instead.
Reject the option lengths RFC 4191 does not allow.
Fixes: 70ceb4f539 ("[IPV6]: ROUTE: Add experimental support for Route Information Option in RA (RFC4191).")
Cc: stable@vger.kernel.org
Signed-off-by: Yuejie Shi <syjcnss@gmail.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260730035310.74584-1-syjcnss@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When fetching the dst_entry from the skb, check if it valid, ie. this is
not a template dst, for extensions that can be used from the netdev
ingress and egress chains.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
nft_flow_tunnel_update_route() can lazy fail, leaving an incomplete
forward path set ip. The route lookup also happens twice, once from
dev_fill_forward_path() and again in this aforementioned function.
Update ipip and ip6ip6 not to release the dst_entry and pass it on
via the tunnel forward path information.
In case of failure when setting up the forwarding path, release the
tunnel dst that was provided via dev_fill_forward_path().
Acked-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The position pointer is only advanced if the return value of the proc
handler is positive at new_sync_write(). Therefore no need to manually
reset it when doing error handling.
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Fernando Fernandez Mancera <fmancera@suse.de>
Link: https://patch.msgid.link/20260727091834.6645-2-fmancera@suse.de
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
When adding a source-specific route creates a new subtree, fib6_add()
installs fib6_null_entry as the temporary leaf of the new subtree root
and takes a fib6_info reference for that holder.
If adding the first source leaf fails, the code frees the just allocated
subtree root but leaves that hold behind. fib6_null_entry is a per-netns
sentinel and is freed directly at netns teardown, so this does not keep
the object alive. However, it leaves its visible refcount permanently
elevated and can eventually saturate the refcount on repeated failures.
Drop the null-entry reference before freeing the unlinked subtree root.
Fixes: 5ea715289a ("ipv6: broadly use fib6_info_hold() helper")
Signed-off-by: Shuangpeng Bai <shuangpeng.kernel@gmail.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Link: https://patch.msgid.link/20260727185339.1545169-1-shuangpeng.kernel@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reuse the flowi6 template t->fl.u.ip6 built by ip6_tnl_link_config() in
ip6_tnl_fill_forward_path(), aligning the fast-path route lookup with
the slow path in ipxip6_tnl_xmit(). This automatically inherits the
correct conditional FLOWLABEL masking based on the
IP6_TNL_F_USE_ORIG_FLOWLABEL flag.
Return -EOPNOTSUPP when IP6_TNL_F_USE_ORIG_TCLASS,
IP6_TNL_F_USE_ORIG_FLOWLABEL or IP6_TNL_F_USE_ORIG_FWMARK is set,
or for collect_md tunnels, since fill_forward_path has no access to
the original skb and cannot recover the per-packet traffic class,
flowlabel, mark or tunnel destination needed for the route lookup.
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Link: https://patch.msgid.link/20260724-ip6ip6-route-lookup-fill_forward_path-v3-1-7b7991538614@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
fib6_rule_suppress() drops a suppressed route with ip6_rt_put_flags(),
but leaves res->rt6 pointing at the released rt6_info.
If no later rule supplies a replacement, fib6_rule_lookup() still sees
res.rt6 and returns that stale dst to its caller. A suppressing rule can
therefore leak a released route back to rt6_lookup(), and the next put
hits rcuref_put_slowpath() from dst_release().
Clear res->rt6 when suppressing the route so suppressed lookups fall
through to the null dst instead of reusing the released one.
Fixes: cdef485217 ("ipv6: fix memory leak in fib6_rule_suppress")
Cc: stable@vger.kernel.org
Reported-by: Vega <vega@nebusec.ai>
Signed-off-by: Zhiling Zou <zhilinz@nebusec.ai>
Signed-off-by: Ren Wei <enjou1224z@gmail.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/4b8acb7787d54e440155585dd32ebdf0bef7d122.1784710966.git.zhilinz@nebusec.ai
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When inet_getpeer_v4() or inet_getpeer_v6() fails to allocate a peer entry
under memory pressure or tree size caps, redirect handlers previously fell
back to sending un-rate-limited ICMP/NDISC Redirect messages.
In IPv4, ip_rt_send_redirect() called icmp_send() directly when peer == NULL.
In IPv6, ip6_forward() and ndisc_send_redirect() passed a NULL peer into
inet_peer_xrlim_allow(), which returned true when peer == NULL.
Because ICMP/NDISC Redirects are not part of the default global rate limit
mask (sysctl_icmp_ratemask), sending redirects when peer == NULL creates
an un-rate-limited ICMP packet storm.
Fix this by failing closed in ip_rt_send_redirect(), ip6_forward(), and
ndisc_send_redirect() when peer is NULL.
Fixes: 92d8682926 ("inetpeer: Move ICMP rate limiting state into inet_peer entries.")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260724072901.1633601-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Cross-merge networking fixes after downstream PR (net-7.2-rc5).
Conflicts:
drivers/net/amt.c
3656a79f94 ("amt: re-read skb header pointers after every pull")
586c4dcf28 ("amt: no longer rely on RTNL in amt_fill_info()")
https://lore.kernel.org/amIaJr3aOQNS_Fvl@sirena.org.uk
Adjacent changes:
drivers/net/geneve.c
8efb8f8bbb ("geneve: require CAP_NET_ADMIN in the device netns for changelink")
0ba269933f ("geneve: convert config to RCU-protected pointer")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Since the call to __ip6_del_rt_siblings has been converted under
rcu read lock and it only has one call point
we should no longer block or yield.
Our stack trace from the syzbot reproducer looks as follows:
__ip6_del_rt_siblings
rtnl_notify (Here we pass gfp_any() -> GFP_KERNEL)
nlmsg_notify
nlmsg_multicast
nlmsg_multicast_filtered
netlink_broadcast_filtered (GFP_KERNEL passed from earlier)
netlink_broadcast_filtered can yield if GFP_KERNEL
is passed, which we do not want to happen.
Fix this by changing the allocation flag of rtnl_notify.
Also change the flag passed to nlmsg_new. Even though it
is not related to the syzbot generated bug it still falls
under the same requirements.
Reported-by: syzbot+84d4a405ed798b40c96d@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=84d4a405ed798b40c96d
Fixes: bd11ff421d ("ipv6: Get rid of RTNL for SIOCDELRT and RTM_DELROUTE.")
Signed-off-by: Nikola Z. Ivanov <zlatistiv@gmail.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260719105759.558050-1-zlatistiv@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
In raw6_icmp_error(), raw_v6_match() is called with inet6_iif(skb) passed
to both the 'dif' and 'sdif' arguments. This is a copy-paste or typo error,
as the last argument should represent the secondary interface index (sdif).
This mismatch breaks ICMPv6 error handling for IPv6 raw sockets in VRF
(Virtual Routing and Forwarding) environments. When a raw socket is bound
to a VRF master device, raw_v6_match() fails to find a match because it is
not given the correct sdif value, causing the socket to miss relevant
ICMPv6 error notifications.
Fix this by properly passing inet6_sdif(skb) as the last argument to
raw_v6_match().
Fixes: 5108ab4bf4 ("net: ipv6: add second dif to raw socket lookups")
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Reviewed-by: Joe Damato <joe@dama.to>
Link: https://patch.msgid.link/20260717143230.1836-1-lirongqing@baidu.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Before commit 00d066a4d4 ("netdev_features: convert NETIF_F_LLTX to
dev->lltx"), NETIF_F_LLTX was set unconditionally in both
__gre_tunnel_init() and ip6gre_tnl_init_features() alongside
GRE_FEATURES:
dev->features |= GRE_FEATURES | NETIF_F_LLTX;
When that commit converted NETIF_F_LLTX to the dev->lltx flag, it
placed 'dev->lltx = true' after the SEQ/CSUM early returns instead
of before them. This causes GRE/GRETAP/ip6gre tunnels with SEQ or
CSUM+encap to lose lockless TX, reintroducing _xmit_lock acquisition
around their ndo_start_xmit. Since GRE xmit re-enters the stack via
ip_tunnel_xmit(), holding _xmit_lock risks ABBA deadlock with the
underlay device.
CPU0 CPU1
---- ----
lock(&qdisc_xmit_lock_key#6);
lock(&qdisc_xmit_lock_key#3);
lock(&qdisc_xmit_lock_key#6);
lock(&qdisc_xmit_lock_key#3);
Fix by moving dev->lltx = true before the early returns in both
functions, restoring the original unconditional behavior.
Fixes: 00d066a4d4 ("netdev_features: convert NETIF_F_LLTX to dev->lltx")
Signed-off-by: Yun Zhou <yun.zhou@windriver.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260713150945.1779628-1-yun.zhou@windriver.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
ila_csum_adjust_transport() caches ip6h = ipv6_hdr(skb) before calling
pskb_may_pull(). On a non-linear skb whose transport header sits in a page
fragment, pskb_may_pull() can call __pskb_pull_tail() / pskb_expand_head()
and free the old skb head, leaving ip6h dangling; the following
get_csum_diff(ip6h, p) then reads freed memory. ila_update_ipv6_locator()
uses ip6h (and the iaddr derived from it) again after the csum-adjust
call and additionally writes the new locator through that pointer.
Impact: a remote IPv6 packet routed through a configured ILA
csum-adjust-transport route or receive-side mapping triggers a
slab-use-after-free in ila_update_ipv6_locator() (KASAN). The route or
mapping requires CAP_NET_ADMIN to configure, but trigger packets are
unauthenticated once it exists.
Reload ip6h after each pskb_may_pull() in ila_csum_adjust_transport()
before the csum-diff read. In ila_update_ipv6_locator() only the
ILA_CSUM_ADJUST_TRANSPORT case pulls the skb, so reload ip6h and iaddr in
that case alone before the destination-address write; the neutral-map
modes never pull and keep their cached pointers.
Fixes: 33f11d1614 ("ila: Create net/ipv6/ila directory")
Cc: stable@vger.kernel.org
Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Antoine Tenart <atenart@kernel.org>
Link: https://patch.msgid.link/20260714114903.3763420-1-michael.bommarito@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
After SRv6 encapsulation the kernel looks up the route for the first SID,
that is the outer IPv6 destination of the encapsulated packet. This
post-encap SID route lookup uses the FIB table of the current routing
context. When the encap route is installed in a VRF, the VRF's table may
not have a route matching the SID. In that case another table should
handle it, e.g. one configured for underlay connectivity.
Add an optional SEG6_IPTUNNEL_TABLE attribute that selects the FIB table
used for this lookup. When set by the user, the attribute is honored on
both the input path (forwarded traffic) and the output path (locally
originated traffic). SRv6 encap routes that do not set the attribute use
the current routing context, as before.
For example:
# SID route installed in the underlay table 500
ip -6 route add fc00::100/128 via fd00::1 dev veth0 table 500
# encap route in vrf-100; the first SID is looked up in table 500
ip -6 route add cafe::1/128 vrf vrf-100 \
encap seg6 mode encap segs fc00::100 lookup 500 dev veth0
# or look up the SID in the main table
ip -6 route add cafe::1/128 vrf vrf-100 \
encap seg6 mode encap segs fc00::100 lookup main dev veth0
Suggested-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: Andrea Mayer <andrea.mayer@uniroma2.it>
Reviewed-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20260711162907.6521-2-andrea.mayer@uniroma2.it
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Alice Mikityanska says:
====================
BIG TCP for UDP tunnels
This series is a follow-up to "BIG TCP without HBH in IPv6", and it adds
support for BIG TCP IPv4/IPv6 workloads in vxlan and geneve. Now that
IPv6 BIG TCP doesn't require stripping the HBH in all various
combinations in tunneled traffic, adding BIG TCP becomes feasible.
Patch 01 adds accessors for the length field in the UDP header, as
suggested by Paolo in review. The usage of udp_set_len is then added in
the following patches that start using length=0 in BIG TCP UDP packets.
Patches 02-04 close the gaps that prevent BIG TCP packets from going
through UDP tunnel code.
Patch 05 validates packets in udp_gro_receive to exclude packets with
length=0 from GRO aggregation.
Patch 06 is for proper formatting in tcpdump (set UDP len to 0 rather
than a trimmed value on overflow).
Patches 07-08 bump up tso_max_size for VXLAN and GENEVE.
Patch 09 adds selftests.
====================$
Link: https://patch.msgid.link/20260710134242.216538-1-alice.kernel@fastmail.im
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
skb->len may be bigger than 65535 in UDP-based tunnels that have BIG TCP
enabled. If GSO aggregates packets that large, set the length in the UDP
header to 0, so that tcpdump can print such packets properly (treating
them as RFC 2675 jumbograms). Later in the pipeline, __udp_gso_segment
will set uh->len to the size of individual packets.
Signed-off-by: Alice Mikityanska <alice@isovalent.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260710134242.216538-7-alice.kernel@fastmail.im
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Currently, gro_max_size and gro_ipv4_max_size can be set to values
bigger than 65536, and GRO will happily aggregate UDP to the configured
size (for example, with TCP traffic in VXLAN tunnels). However,
udp_gro_complete uses the 16-bit length field in the UDP header to store
the length of the aggregated packet. It leads to the packet truncation
later in udp_rcv.
Fix this by storing 0 to the UDP length field and by restoring the real
length from skb->len in udp_rcv. IP GRO already can store 0 to the IP
length field, and iph_totlen()/ipv6_payload_len() are capable of
restoring the real length, because the relevant packets (BIG TCP
tunneled in UDP tunnels) will have skb_is_gso_tcp == true.
Additionally, restrict handling uh->len=0 in udpv6_rcv to BIG TCP and
jumbograms only by using the udp_get_len helper.
Signed-off-by: Alice Mikityanska <alice@isovalent.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260710134242.216538-5-alice.kernel@fastmail.im
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Wherever a GSO packet can occur, and its length is used to fill the UDP
header, use udp_set_len that assigns 0 if the length doesn't fit 16
bits, so that the packet can be properly parsed and segmented later,
instead of having truncated length.
Use udp_get_len in udp_validate_len to treat BIG TCP packets as valid.
Signed-off-by: Alice Mikityanska <alice@isovalent.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260710134242.216538-4-alice.kernel@fastmail.im
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Since BIG TCP for UDP tunnels will start using len=0 in the UDP header
as an indicator of a GSO packet bigger than 65535 bytes, this commit
introduces the following getter and setters to use tree-wide, in order
to explicitly mark places where len=0 may be expected, and handle them
properly:
1. udp_set_len() sets uh->len to its real value if it's not bigger than
65535, and to 0 otherwise: to be used in GSO context with aggregated
packets.
2. udp_set_len_short() is to be used when the length is known to fit 16
bits. It WARNs when the caller tries to assign a bigger value if
CONFIG_DEBUG_NET=y.
3. udp_get_len_short() returns len in host byte order: to be used on the
RX side to deal with non-aggregated packets, or to access the raw value
of the len field.
4. udp_get_len() decodes uh->len set by udp_set_len(). It checks whether
the packet is GSO to guard from malformed packets.
At the moment udp_set_len() is not used, a following commit will start
using it after enabling len>65535 for GSO.
Raw uh->len (in network byte order) is still accessed in a few places
for checksum calculation purposes, and to decode len=0 in udpv6_rcv for
jumbograms. udp_rcv and udpv6_rcv will be addressed by the commit that
starts using udp_set_len() to set UDP len=0 for BIG TCP packets in UDP
tunnels.
Signed-off-by: Alice Mikityanska <alice@isovalent.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Acked-by: Jason A. Donenfeld <Jason@zx2c4.com>
Link: https://patch.msgid.link/20260710134242.216538-2-alice.kernel@fastmail.im
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
tcp_v4_send_ack() and tcp_v6_send_response() construct standalone TCP
responses with TCP-AO options. The option length carries the actual MAC
length, but the TCP header length includes the option rounded up to a
four-byte boundary.
tcp_ao_hash_hdr() writes the MAC only. Thus, when the MAC length is not
four-byte aligned, the one to three bytes after the MAC are left
uninitialized and may be transmitted. For the normal TCP-AO hashing
mode, those bytes also have to be initialized before computing the MAC.
Initialize only the alignment padding in the TCP-AO branches, before
hashing the header. Use TCPOPT_NOP, as in the normal TCP-AO output path.
This avoids adding work to non-AO TCP responses while preserving a valid
authenticated header.
Fixes: decde2586b ("net/tcp: Add TCP-AO sign to twsk")
Fixes: da7dfaa6d6 ("net/tcp: Consistently align TCP-AO option in the header")
Cc: stable@vger.kernel.org
Reported-by: Yizhou Zhao <zhaoyz24@mails.tsinghua.edu.cn>
Reported-by: Yuxiang Yang <yangyx22@mails.tsinghua.edu.cn>
Reported-by: Ao Wang <wangao@seu.edu.cn>
Reported-by: Xuewei Feng <fengxw06@126.com>
Reported-by: Qi Li <qli01@tsinghua.edu.cn>
Reported-by: Ke Xu <xuke@tsinghua.edu.cn>
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Yizhou Zhao <zhaoyz24@mails.tsinghua.edu.cn>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260713105631.8616-1-zhaoyz24@mails.tsinghua.edu.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When a UDP encapsulation socket (e.g., FOU) receives a multicast
packet, __udp4_lib_mcast_deliver() and __udp6_lib_mcast_deliver()
call consume_skb() when udp_queue_rcv_skb() returns a positive value.
A positive return value from udp_queue_rcv_skb() indicates that the
encap_rcv handler (e.g., fou_udp_recv) has consumed the UDP header
and wants the packet to be resubmitted to the IP protocol handler
for further processing (e.g., as a GRE packet).
The unicast paths handle this correctly by propagating the return
value up to ip_protocol_deliver_rcu() / ip6_protocol_deliver_rcu()
for resubmission. However, the multicast paths destroy the packet
via consume_skb() instead of resubmitting it, causing silent packet
loss.
This affects any UDP encapsulation (FOU, GUE) combined with multicast
destination addresses.
Fix this by returning the value from udp_queue_rcv_skb() when it is
positive, matching the behavior of the corresponding unicast paths.
Note the sign difference between IPv4 and IPv6:
- IPv4: udp_unicast_rcv_skb() returns -ret, and
ip_protocol_deliver_rcu() resubmits when ret < 0
(using -ret as the protocol number).
- IPv6: udp6_unicast_rcv_skb() returns ret, and
ip6_protocol_deliver_rcu() resubmits when ret > 0
(using ret as the nexthdr).
Both mcast paths now follow the same convention as their respective
unicast paths.
Suggested-by: Kuniyuki Iwashima <kuniyu@google.com>
Signed-off-by: Anton Danilov <littlesmilingcloud@gmail.com>
Assisted-by: Claude:claude-opus-4-6
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/5372ccac062193147e02b991d5328a5c3fa3a85a.1783372173.git.littlesmilingcloud@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Release the TIME_WAIT socket reference and jump to discard_it
upon PSP policy failure in both IPv4 and IPv6 receive paths.
This prevents a memory leak of tcp_tw_bucket structures.
Fixes: 659a2899a5 ("tcp: add datapath logic for PSP with inline key exchange")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Daniel Zahka <daniel.zahka@gmail.com>
Link: https://patch.msgid.link/20260710181317.4060230-1-edumazet@google.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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Merge tag 'nf-26-07-10' of https://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf
Florian Westphal says:
====================
netfilter: updates for net
The following patchset contains Netfilter fixes for *net*.
These are fixes for bugs except patches 6 and 9 which fix issues added in
last PR and 7.1-rc1.
1) Reject unsupported target families in xt_nat_checkentry().
From Wyatt Feng.
2) Fix inverted time_after() check in ecache_work_evict_list().
Causes pointless work rescheds and thus way longer time to
clear the pending event backlog. From Yizhou Zhao.
3) Fix a use-after-free in br_ip6_fragment() caused by a dangling prevhdr
pointer. From Xiang Mei.
4) Fix incorrect conntrack zone comparison in nf_conncount tuple
deduplication. Pass IP_CT_DIR_ORIGINAL, not zone direction.
From Yizhou Zhao.
5) Add bridge tunnel flowtable regression test for a bug that
got fixed in the previous PR. From Zhengyang Chen.
6) Use the correct direction when setting up tunnel routes in the flowtable
xmit path. From Pablo Neira Ayuso. This fixes a bug added in the
previous PR.
7) Reload IP header after potential skb head reallocation in IPVS.
8) Fix incorrect IPv6 transport offsets in TCP application code. Correct the
ICMPv6 header offset to ensure proper checksumming with extension headers,
from Julian Anastasov. this is a followup to the previous PR.
9) Remove null-termination requirement for xt_physdev masks, this broke
device names with 15 characters.
netfilter pull request nf-26-07-10
* tag 'nf-26-07-10' of https://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
netfilter: xt_physdev: masks are not c-strings
ipvs: fix more places with wrong ipv6 transport offsets
ipvs: reload ip header after head reallocation
netfilter: flowtable: use correct direction to set up tunnel route
selftests: netfilter: add bridge tunnel flowtable regression
netfilter: nf_conncount: fix zone comparison in tuple dedup
netfilter: bridge: fix stale prevhdr pointer in br_ip6_fragment()
netfilter: ecache: fix inverted time_after() check
netfilter: xt_nat: reject unsupported target families
====================
Link: https://patch.msgid.link/20260710143733.29741-1-fw@strlen.de
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
