Commit Graph

13537 Commits

Author SHA1 Message Date
Jakub Kicinski
6a4c4656b0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR (net-7.1-rc3).

Conflicts:

net/ipv4/igmp.c
  726fa7da2d ("ipv4: igmp: get rid of IGMPV3_{QQIC,MRC} and simplify calculation")
  c6bebaa744 ("ipv4: igmp: annotate data-races in igmp_heard_query()")
https://lore.kernel.org/a7365e4873340f7a5e30411207de3bf9@kernel.org

Adjacent changes:

net/psp/psp_main.c
  30cb24f97d ("psp: strip variable-length PSP header in psp_dev_rcv()")
  c2b22277ad ("psp: validate IPv4 header fields in psp_dev_rcv()")

net/sched/sch_fq_codel.c
  f83e07b292 ("net/sched: sch_fq_codel: annotate data-races from fq_codel_dump_class_stats()")
  3f3aa77ff1 ("net/sched: add qstats_cpu_drop_inc() helper")

net/wireless/pmsr.c
  0f3c0a1973 ("wifi: nl80211: fix NL80211_PMSR_FTM_REQ_ATTR_FTMS_PER_BURST usage")
  410aa47fd9 ("wifi: cfg80211: allow suppressing FTM result reporting for PD requests")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-07 11:19:07 -07:00
Kuniyuki Iwashima
019c892e46 ipmr: Call ipmr_fib_lookup() under RCU.
Yi Lai reported RCU splat in reg_vif_xmit() below. [0]

When CONFIG_IP_MROUTE_MULTIPLE_TABLES=n, ipmr_fib_lookup()
uses rcu_dereference() without explicit rcu_read_lock().

Although rcu_read_lock_bh() is already held by the caller
__dev_queue_xmit(), lockdep requires explicit rcu_read_lock()
for rcu_dereference().

Let's move up rcu_read_lock() in reg_vif_xmit() to
cover ipmr_fib_lookup().

[0]:
WARNING: suspicious RCU usage
7.1.0-rc2-next-20260504-9d0d467c3572 #1 Not tainted
 -----------------------------
net/ipv4/ipmr.c:329 suspicious rcu_dereference_check() usage!

other info that might help us debug this:

rcu_scheduler_active = 2, debug_locks = 1
2 locks held by syz.2.17/1779:
 #0: ffffffff87896440 (rcu_read_lock_bh){....}-{1:3}, at: local_bh_disable include/linux/bottom_half.h:20 [inline]
 #0: ffffffff87896440 (rcu_read_lock_bh){....}-{1:3}, at: rcu_read_lock_bh include/linux/rcupdate.h:891 [inline]
 #0: ffffffff87896440 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x239/0x4140 net/core/dev.c:4792
 #1: ffff88801a199d18 (_xmit_PIMREG#2){+...}-{3:3}, at: spin_lock include/linux/spinlock.h:342 [inline]
 #1: ffff88801a199d18 (_xmit_PIMREG#2){+...}-{3:3}, at: __netif_tx_lock include/linux/netdevice.h:4795 [inline]
 #1: ffff88801a199d18 (_xmit_PIMREG#2){+...}-{3:3}, at: __dev_queue_xmit+0x1d5d/0x4140 net/core/dev.c:4865

stack backtrace:
CPU: 1 UID: 0 PID: 1779 Comm: syz.2.17 Not tainted 7.1.0-rc2-next-20260504-9d0d467c3572 #1 PREEMPT(lazy)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x121/0x150 lib/dump_stack.c:120
 dump_stack+0x19/0x20 lib/dump_stack.c:129
 lockdep_rcu_suspicious+0x15b/0x1f0 kernel/locking/lockdep.c:6878
 ipmr_fib_lookup net/ipv4/ipmr.c:329 [inline]
 reg_vif_xmit+0x2ee/0x3c0 net/ipv4/ipmr.c:540
 __netdev_start_xmit include/linux/netdevice.h:5382 [inline]
 netdev_start_xmit include/linux/netdevice.h:5391 [inline]
 xmit_one net/core/dev.c:3889 [inline]
 dev_hard_start_xmit+0x170/0x700 net/core/dev.c:3905
 __dev_queue_xmit+0x1df1/0x4140 net/core/dev.c:4871
 dev_queue_xmit include/linux/netdevice.h:3423 [inline]
 packet_xmit+0x252/0x370 net/packet/af_packet.c:276
 packet_snd net/packet/af_packet.c:3082 [inline]
 packet_sendmsg+0x39ad/0x5650 net/packet/af_packet.c:3114
 sock_sendmsg_nosec net/socket.c:797 [inline]
 __sock_sendmsg net/socket.c:812 [inline]
 ____sys_sendmsg+0xa21/0xba0 net/socket.c:2716
 ___sys_sendmsg+0x121/0x1c0 net/socket.c:2770
 __sys_sendmsg+0x177/0x220 net/socket.c:2802
 __do_sys_sendmsg net/socket.c:2807 [inline]
 __se_sys_sendmsg net/socket.c:2805 [inline]
 __x64_sys_sendmsg+0x80/0xc0 net/socket.c:2805
 x64_sys_call+0x1d9c/0x21c0 arch/x86/include/generated/asm/syscalls_64.h:47
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc1/0x1020 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f37e563ee5d
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 93 af 1b 00 f7 d8 64 89 01 48
RSP: 002b:00007ffe5caa7fa8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00000000005c5fa0 RCX: 00007f37e563ee5d
RDX: 0000000000000000 RSI: 00002000000012c0 RDI: 0000000000000004
RBP: 00000000005c5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00000000005c5fac R15: 00000000005c5fa0
 </TASK>

Fixes: b3b6babf47 ("ipmr: Free mr_table after RCU grace period.")
Reported-by: syzkaller <syzkaller@googlegroups.com>
Reported-by: Yi Lai <yi1.lai@intel.com>
Closes: https://lore.kernel.org/netdev/afrY34dLXNUboevf@ly-workstation/
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260506065955.1695753-1-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-07 08:38:37 -07:00
Eric Dumazet
c8f7244c8c tcp: tcp_child_process() related UAF
tcp_child_process( .. child ...) currently calls sock_put(child).

Unfortunately @child (named @nsk in callers) can be used after
this point to send a RST packet.

To fix this UAF, I remove the sock_put() from tcp_child_process()
and let the callers handle this after it is safe.

Remove @rsk variable in tcp_v4_do_rcv() and change tcp_v6_do_rcv()
so that both functions look the same.

Fixes: cfb6eeb4c8 ("[TCP]: MD5 Signature Option (RFC2385) support.")
Reported-by: Damiano Melotti <melotti@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260505153927.3435532-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-06 18:11:33 -07:00
Eric Dumazet
67ef49047d inetpeer: add a missing read_seqretry() in inet_getpeer()
When performing a lockless lookup over the inet_peer rbtree,
if a matching node is found, inet_getpeer() returns it immediately
without validating the seqlock sequence.

This missing check introduces a race condition:

Trigger Path: When a host receives an incoming fragmented IPv4 packet,
ip4_frag_init() (in net/ipv4/ip_fragment.c) calls inet_getpeer_v4()
to track the peer.

The Race: If the packet is from a new source IP, CPU A acquires the
write_seqlock, allocates a new inet_peer node (p), sets its IP address
(daddr), and links it to the rbtree (rb_link_node).

Uninitialized Access: Due to the lack of memory barriers between
rb_link_node and the initialization of the rest of the struct
(like refcount_set(&p->refcnt, 1)), CPU A can make the node visible
to readers before its refcnt is initialized.
This is especially true on weakly-ordered architectures like ARM64
where the CPU can reorder the memory stores.

Lockless Reader: Concurrently, CPU B processes a second fragmented packet
from the same source IP. CPU B does a lockless lookup, finds the newly
inserted node, and returns it immediately.

Use-After-Free (UAF): CPU B reads p->refcnt as uninitialized garbage
(left over from previous kmalloc-128/192 allocations).
If the garbage is > 0, refcount_inc_not_zero(&p->refcnt) succeeds.
CPU A then executes refcount_set(&p->refcnt, 1), overwriting CPU B's increment.
When CPU B finishes with the fragment queue, it calls inet_putpeer(),
which drops the refcount to 0 and frees the node via RCU.
The node is now freed but remains linked in the rbtree,
resulting in a Use-After-Free in the rbtree.

Fixes: b145425f26 ("inetpeer: remove AVL implementation in favor of RB tree")
Reported-by: Damiano Melotti <melotti@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260505133233.3039575-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-06 17:44:13 -07:00
Jakub Kicinski
dc61989e37 Merge tag 'ipsec-2026-05-05' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec
Steffen Klassert says:

====================
pull request (net): ipsec 2026-05-05

1. Fix an IPv6 encapsulation error path that leaked route references
   when UDPv6 ESP decapsulation resolved to an error route.
   From Yilin Zhu.

2. Fix AH with ESN on async crypto paths by accounting for the extra
   high-order sequence number when reconstructing the temporary
   authentication layout in the completion callbacks.
   From Michael Bomarito.

3. Fix XFRM output so it does not overwrite already-correct inner header
   pointers when a tunnel layer such as VXLAN has already saved them.
   The fix comes with new selftests. From Cosmin Ratiu.

4. Add the missing native payload size entry for XFRM_MSG_MAPPING in the
   compat translation path. From Ruijie Li.

5. Harden __xfrm_state_delete() against repeated or inconsistent unhashing
   of state list nodes by keying the removal on actual list membership and
   using delete-and-init helpers. From Michal Kosiorek.

6. Prevent ESP from decrypting shared splice-backed skb fragments in place
   by marking UDP splice frags as shared and forcing copy-on-write in ESP
   input when needed. From Kuan-Ting Chen.

* tag 'ipsec-2026-05-05' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec:
  xfrm: esp: avoid in-place decrypt on shared skb frags
  xfrm: defensively unhash xfrm_state lists in __xfrm_state_delete
  xfrm: provide message size for XFRM_MSG_MAPPING
  xfrm: Don't clobber inner headers when already set
  tools/selftests: Add a VXLAN+IPsec traffic test
  tools/selftests: Use a sensible timeout value for iperf3 client
  xfrm: ah: account for ESN high bits in async callbacks
  ipv6: xfrm6: release dst on error in xfrm6_rcv_encap()
====================

Link: https://patch.msgid.link/20260505132326.1362733-1-steffen.klassert@secunet.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-06 16:49:42 -07:00
Kuniyuki Iwashima
72d3b9a4c2 udp_tunnel: Remove synchronize_rcu() in udp_tunnel_sock_release().
Commit 3cf7203ca6 ("net/tunnel: wait until all sk_user_data
reader finish before releasing the sock") added synchronize_rcu()
in udp_tunnel_sock_release().

This was intended to protect the fast path of a dying vxlan device
from dereferencing vxlan_sock->sock->sk after sock_orphan() has set
sock->sk to NULL.

However, vxlan does not need to access struct socket itself
in the fast path; it only reads struct sock, and struct socket
is only used for tunnel setup and teardown.

This applies to all other UDP tunnel users, and they have been
converted to access struct sock directly.

In addition, each device-specific struct used in their fast paths
is freed after one RCU grace period.  Since this occurs after
udp_tunnel_sock_release(), the struct is guaranteed to be freed
after struct udp_sock.

Therefore, synchronize_rcu() in udp_tunnel_sock_release() is
now redundant.

Let's remove it.

Tested:

A script creating/upping vxlan devices in 4000 netns runs 10x
faster with this change.  We can see the same improvement with
other UDP tunnel devices as well.

  $ cat vxlan.sh
  for i in `seq 1 40`
  do
      (for j in `seq 1 100` ; do
            unshare -n bash -c "ip link add vxlan0 type vxlan id 100 local 127.0.0.1 dstport 4789 && ip link set vxlan0 up";
       done) &
  done
  wait

With bpftrace, we can see vxlan_stop() is significantly faster.

  bpftrace -e '
  kprobe:vxlan_stop {
          @start[tid] = nsecs;
  }

  kretprobe:vxlan_stop /@start[tid]/ {
          @duration_us = hist((nsecs - @start[tid]) / 1000);
          delete(@start[tid]);
  }

  END {
          printf("\nExecution time of vxlan_stop (us):\n");
  }'

Before:

  # time ./vxlan.sh // without bpftrace
  real	0m50.615s
  user	0m8.171s
  sys	1m45.101s

  @duration_us:
  [4K, 8K)            1266 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@                   |
  [8K, 16K)           1957 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@|
  [16K, 32K)           764 |@@@@@@@@@@@@@@@@@@@@                                |
  [32K, 64K)             6 |                                                    |
  [64K, 128K)            4 |                                                    |
  [128K, 256K)           3 |                                                    |

After:

  # time ./vxlan.sh // without bpftrace
  real	0m5.247s
  user	0m7.956s
  sys	1m47.404s

  @duration_us:
  [16, 32)            3411 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@|
  [32, 64)             383 |@@@@@                                               |
  [64, 128)            107 |@                                                   |
  [128, 256)            79 |@                                                   |
  [256, 512)            16 |                                                    |
  [512, 1K)              2 |                                                    |
  [1K, 2K)               2 |                                                    |

Next step is to remove another synchronize_net() in vxlan_stop()
and variants in other devices.

Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260502031401.3557229-16-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-05 17:47:06 -07:00
Kuniyuki Iwashima
173a79f696 fou: Store struct sock in struct fou.
fou does not need to access struct socket itself in the fast
path; it only reads struct sock, and struct socket is only used
for tunnel setup and teardown.

Let's store struct sock directly in struct fou.

fou_release() frees struct fou with kfree_rcu(), so fou no
longer needs synchronize_rcu() in udp_tunnel_sock_release().

Note that the error path in fou_create() looks buggy; once the
tunnel is set up and fou_add_to_port_list() fails, struct fou
should be freed with kfree_rcu() _after_ udp_tunnel_sock_release().

Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260502031401.3557229-12-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-05 17:47:05 -07:00
Kuniyuki Iwashima
af3f903fbb udp_tunnel: Pass struct sock to udp_tunnel_notify_{add,del}_rx_port().
None of the udp_tunnel users need struct socket in their
fast paths; it is only used for tunnel setup / teardown.

Even udp_tunnel_notify_{add,del}_rx_port() do not need
struct socket.

Let's change udp_tunnel_notify_{add,del}_rx_port() to take
struct sock instead of struct socket.

Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260502031401.3557229-6-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-05 17:47:04 -07:00
Kuniyuki Iwashima
8d0012ce1b udp_tunnel: Pass struct sock to udp_tunnel_{push,drop}_rx_port().
None of the udp_tunnel users need struct socket in their
fast paths; it is only used for tunnel setup / teardown.

Even udp_tunnel_{push,drop}_rx_port() do not need struct socket.

Let's change udp_tunnel_{push,drop}_rx_port() to take struct
sock instead of struct socket.

Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260502031401.3557229-5-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-05 17:47:04 -07:00
Kuniyuki Iwashima
2cba193628 udp_tunnel: Pass struct sock to setup_udp_tunnel_sock().
None of the udp_tunnel users need struct socket in their
fast paths; it is only used for tunnel setup / teardown.

Even setup_udp_tunnel_sock() does not need struct socket.

Let's change setup_udp_tunnel_sock() to take struct sock
instead of struct socket.

Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260502031401.3557229-3-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-05 17:47:04 -07:00
Kuniyuki Iwashima
944bfc1b1c udp_tunnel: Pass struct sock to udp_tunnel_sock_release().
None of the udp_tunnel users need struct socket in their
fast paths; it is only used for tunnel setup / teardown.

While the UDP tunnel interface accepts struct socket, this
encourages users to store the pointer unnecessarily.  This
leads to extra dereferences when accessing struct sock fields
(e.g., sk->sk_user_data instead of sock->sk->sk_user_data).

Furthermore, these dereferences necessitate synchronize_rcu()
in udp_tunnel_sock_release() to protect the fast paths from
sock_orphan() setting sk->sk_socket to NULL.

This overhead can be avoided if users store the struct sock
pointer directly in their private structures.

As a prep, let's change udp_tunnel_sock_release() to take
struct sock instead of struct socket.

Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260502031401.3557229-2-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-05 17:47:03 -07:00
Kuan-Ting Chen
f4c50a4034 xfrm: esp: avoid in-place decrypt on shared skb frags
MSG_SPLICE_PAGES can attach pages from a pipe directly to an skb. TCP
marks such skbs with SKBFL_SHARED_FRAG after skb_splice_from_iter(),
so later paths that may modify packet data can first make a private
copy. The IPv4/IPv6 datagram append paths did not set this flag when
splicing pages into UDP skbs.

That leaves an ESP-in-UDP packet made from shared pipe pages looking
like an ordinary uncloned nonlinear skb. ESP input then takes the no-COW
fast path for uncloned skbs without a frag_list and decrypts in place
over data that is not owned privately by the skb.

Mark IPv4/IPv6 datagram splice frags with SKBFL_SHARED_FRAG, matching
TCP. Also make ESP input fall back to skb_cow_data() when the flag is
present, so ESP does not decrypt externally backed frags in place.
Private nonlinear skb frags still use the existing fast path.

This intentionally does not change ESP output. In esp_output_head(),
the path that appends the ESP trailer to existing skb tailroom without
calling skb_cow_data() is not reachable for nonlinear skbs:
skb_tailroom() returns zero when skb->data_len is nonzero, while ESP
tailen is positive. Thus ESP output will either use the separate
destination-frag path or fall back to skb_cow_data().

Fixes: cac2661c53 ("esp4: Avoid skb_cow_data whenever possible")
Fixes: 03e2a30f6a ("esp6: Avoid skb_cow_data whenever possible")
Fixes: 7da0dde684 ("ip, udp: Support MSG_SPLICE_PAGES")
Fixes: 6d8192bd69 ("ip6, udp6: Support MSG_SPLICE_PAGES")
Reported-by: Hyunwoo Kim <imv4bel@gmail.com>
Reported-by: Kuan-Ting Chen <h3xrabbit@gmail.com>
Tested-by: Hyunwoo Kim <imv4bel@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Kuan-Ting Chen <h3xrabbit@gmail.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2026-05-05 06:38:30 +02:00
Ujjal Roy
726fa7da2d ipv4: igmp: get rid of IGMPV3_{QQIC,MRC} and simplify calculation
Get rid of the IGMPV3_MRC macro and use the igmpv3_mrt() API to
calculate the Max Resp Time from the Maximum Response Code.

Similarly, for IGMPV3_QQIC, use the igmpv3_qqi() API to calculate
the Querier's Query Interval from the QQIC field.

Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Ujjal Roy <royujjal@gmail.com>
Link: https://patch.msgid.link/20260502131907.987-2-royujjal@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-04 19:09:41 -07:00
Eric Dumazet
affe6c2765 tcp: move max_packets_out, cwnd_usage_seq, rate_delivered and rate_interval_us to tcp_sock_write_tx group
These fields are used in TX path.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260430100021.211139-6-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-01 17:22:45 -07:00
Eric Dumazet
dd033ec406 tcp: move tp->bytes_acked to tcp_sock_write_tx group
tp->bytes_acked is touched in TX path only.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260430100021.211139-5-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-01 17:22:45 -07:00
Eric Dumazet
07db42c4b3 tcp: move tp->first_tx_mstamp and tp->delivered_mstamp to tcp_sock_write_tx
These fields are touched in when payload is sent.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260430100021.211139-4-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-01 17:22:45 -07:00
Eric Dumazet
2b28dd212a tcp: move tp->segs_in and tp->segs_out to tcp_sock_write_txrx group
segs_in is changed for each incoming packet, including ACK packets.
segs_out is changed for each outgoing packet, including ACK packets.

They belong to tcp_sock_write_txrx group.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260430100021.211139-3-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-01 17:22:45 -07:00
Eric Dumazet
9f810527a3 tcp: move tp->delivered and tp->delivered_ce to tcp_sock_write_tx group
These counters are changed whenever sent data is acknowleged.

They do not belong to tcp_sock_write_txrx group, because TCP receivers
do not touch them.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260430100021.211139-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-01 17:22:44 -07:00
Eric Dumazet
c6bebaa744 ipv4: igmp: annotate data-races in igmp_heard_query()
Multiple cpus can run igmp_heard_query() concurrently.

Add missing READ_ONCE()/WRITE_ONCE() over following in_dev fields.

- mr_qrv
- mr_qi
- mr_qri
- mr_v1_seen
- mr_v2_seen

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reported-by: syzbot+ae9a171f239b14485310@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/69f38675.050a0220.3cbe47.0002.GAE@google.com
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260430164836.872079-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-01 17:11:42 -07:00
Eric Dumazet
4f34002e2e ipmr: prevent info-leak in pmr_cache_report()
Yiming Qian reported:

<quote>
 ipmr_cache_report()` allocates a report skb with `alloc_skb(128,
 GFP_ATOMIC)` and appends a `struct igmphdr` using `skb_put()`. In the
 non-`IGMPMSG_WHOLEPKT` path it initializes only:

 - `igmp->type`
 - `igmp->code`

 but does not initialize:

 - `igmp->csum`
 - `igmp->group`

 Later, `igmpmsg_netlink_event()` copies the bytes after `sizeof(struct
 igmpmsg)` into the `IPMRA_CREPORT_PKT` netlink attribute and emits
 `RTM_NEWCACHEREPORT` on `RTNLGRP_IPV4_MROUTE_R`.

 As a result, 6 bytes of stale heap data from the skb head are
 disclosed to userspace.
</quote>

Let's use skb_put_zero() instead of skb_put() to fix this bug.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reported-by: Yiming Qian <yimingqian591@gmail.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260430070611.4004529-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-01 17:01:40 -07:00
Jakub Kicinski
7c04aa3b2f Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR (net-7.1-rc2).

No conflicts, or adjacent changes.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-30 12:51:05 -07:00
Fernando Fernandez Mancera
0bf00859d7 netfilter: nf_socket: skip socket lookup for non-first fragments
Both nft_socket and xt_socket relies on L4 headers to perform socket
lookup in the slow path. For fragmented packets, while the IP protocol
remains constant across all fragments, only the first fragment contains
the actual L4 header.

As the expression/match could be attached to a chain with a priority
lower than -400, it could bypass defragmentation.

Add a check for fragmentation in the lookup functions directly so the
problem is handled for both nft_socket and xt_socket at the same time.
In addition, future users of the functions would not need to care about
this.

Fixes: 902d6a4c2a ("netfilter: nf_defrag: Skip defrag if NOTRACK is set")
Fixes: 554ced0a6e ("netfilter: nf_tables: add support for native socket matching")
Signed-off-by: Fernando Fernandez Mancera <fmancera@suse.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-04-30 17:59:01 +02:00
Eric Biggers
4baf241599 net/tcp: Remove tcp_sigpool
tcp_sigpool is no longer used.  It existed only as a workaround for
issues in the design of the crypto_ahash API, which have been avoided by
switching to the much easier-to-use library APIs instead.  Remove it.

Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Link: https://patch.msgid.link/20260427172727.9310-6-ebiggers@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-04-30 09:38:56 +02:00
Eric Biggers
8e4f61e431 net/tcp-ao: Return void from functions that can no longer fail
Since tcp-ao now uses the crypto library API instead of crypto_ahash,
and MACs and keys now have a statically-known maximum size, many tcp-ao
functions can no longer fail.  Propagate this change up into the return
types of various functions.

Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Link: https://patch.msgid.link/20260427172727.9310-5-ebiggers@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-04-30 09:38:56 +02:00
Eric Biggers
4816879989 net/tcp-ao: Use stack-allocated MAC and traffic_key buffers
Now that the maximum MAC and traffic key lengths are statically-known
small values, allocate MACs and traffic keys on the stack instead of
with kmalloc.  This eliminates multiple failure-prone GFP_ATOMIC
allocations.

Note that some cases such as tcp_ao_prepare_reset() are left unchanged
for now since they would require slightly wider changes.

Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Link: https://patch.msgid.link/20260427172727.9310-4-ebiggers@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-04-30 09:38:56 +02:00
Eric Biggers
068f5a0095 net/tcp-ao: Use crypto library API instead of crypto_ahash
Currently the kernel's TCP-AO implementation does the MAC and KDF
computations using the crypto_ahash API.  This API is inefficient and
difficult to use, and it has required extensive workarounds in the form
of per-CPU preallocated objects (tcp_sigpool) to work at all.

Let's use lib/crypto/ instead.  This means switching to straightforward
stack-allocated structures, virtually addressed buffers, and direct
function calls.  It also means removing quite a bit of error handling.
This makes TCP-AO quite a bit faster.

This also enables many additional cleanups, which later commits will
handle: removing tcp-sigpool, removing support for crypto_tfm cloning,
removing more error handling, and replacing more dynamically-allocated
buffers with stack buffers based on the now-statically-known limits.

Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Link: https://patch.msgid.link/20260427172727.9310-3-ebiggers@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-04-30 09:38:56 +02:00
Eric Biggers
5eb0cfedb2 net/tcp-ao: Drop support for most non-RFC-specified algorithms
RFC 5926 (https://datatracker.ietf.org/doc/html/rfc5926) specifies the
use of AES-128-CMAC and HMAC-SHA1 with TCP-AO.  This includes a
specification for how traffic keys shall be derived for each algorithm.

Support for any other algorithms with TCP-AO isn't standardized, though
an expired Internet Draft (a work-in-progress document, not a standard)
from 2019 does propose adding HMAC-SHA256 support:
https://datatracker.ietf.org/doc/html/draft-nayak-tcp-sha2-03

Since both documents specify the KDF for each algorithm individually, it
isn't necessarily clear how any other algorithm should be integrated.

Nevertheless, the Linux implementation of TCP-AO allows userspace to
specify the MAC algorithm as a string tcp_ao_add::alg_name naming either
"cmac(aes128)" or an arbitrary algorithm in the crypto_ahash API.  The
set of valid strings is undocumented.  The implementation assumes that
"cmac(aes128)" is the only algorithm that requires an entropy extraction
step and that all algorithms accept keys with length equal to the
untruncated MAC; thus, arbitrary HMAC algorithms probably do work, but
some other MAC algorithms like AES-256-CMAC have never actually worked.

Unfortunately, this undocumented string allows many obsolete, insecure,
or redundant algorithms.  For example, "hmac(md5)" and the
non-cryptographic "crc32" are accepted.  It also ties the implementation
to crypto_ahash and requires that most memory be dynamically allocated,
making the implementation unnecessarily complex and inefficient.  Still
furthermore, this implementation requires the crypto API to support
"transformation cloning", whose only user is this feature.

Fortunately, it's very likely that only a few algorithms are actually
used in practice.  Let's restrict the set of allowed algorithms to
"cmac(aes128)" (or "cmac(aes)" with keylen=16), "hmac(sha1)", and
"hmac(sha256)".  The first two are the actually standard ones, while
HMAC-SHA256 seems like a reasonable algorithm to continue supporting as
a Linux extension, considering the Internet Draft for it and the fact
that SHA-256 is the usual choice of upgrade from the outdated SHA-1.

If any other algorithm ever turns out to be needed, e.g. HMAC-SHA512, it
can of course be (re-)added in library form.  However, note that the TCP
options space limits TCP-AO MACs to 20 bytes (160 bits) anyway, which
limits the potential benefit of any further upgrade to the algorithm.

Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Link: https://patch.msgid.link/20260427172727.9310-2-ebiggers@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-04-30 09:38:56 +02:00
Eric Dumazet
28df22acc2 tcp: add tcp_mstamp_refresh_inline()
We want to inline tcp_mstamp_refresh() in fast path only:

- tcp_rcv_established()
- tcp_write_xmit()

Add tcp_mstamp_refresh_inline() for this purpose.

Add noinline qualifier on tcp_mstamp_refresh() for the other paths,
to reduce bloat.

$ scripts/bloat-o-meter -t vmlinux.old vmlinux.new
add/remove: 0/0 grow/shrink: 1/4 up/down: 26/-123 (-97)
Function                                     old     new   delta
tcp_rcv_established                         2238    2264     +26
tcp_connect                                 4027    4003     -24
tcp_tsq_write                                152     120     -32
tcp_send_active_reset                        476     444     -32
tcp_send_window_probe                        235     200     -35
Total: Before=25316710, After=25316613, chg -0.00%

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Neal Cardwell <ncardwell@google.com>
Link: https://patch.msgid.link/20260429010809.784315-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-29 19:02:47 -07:00
Jakub Kicinski
67d7ae3340 Merge tag 'nf-26-04-28' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf
Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains Netfilter fixes for net:

1) IEEE1394 ARP payload contains no target hardware address in the
   ARP packet. Apparently, arp_tables was never updated to deal with
   IEEE1394 ARP properly. To deal with this, return no match in case
   the target hardware address selector is used, either for inverse or
   normal match. Moreover, arpt_mangle disallows mangling of the target
   hardware and IP address because, it is not worth to adjust the
   offset calculation to fix this, we suspect no users of arp_tables
   for this family.

2) Use list_del_rcu() to delete device hooks in nf_tables, this hook
   list is RCU protected, concurrent netlink dump readers can be
   walking on this list, fix it by adding a helper function and use it
   for consistency. From Florian Westphal.

3) Add list_splice_rcu(), this is useful for joining the local list of
   new device hooks to the RCU protected hook list in chain and
   flowtable. Reviewed by Paul E. McKenney.

4) Use list_splice_rcu() to publish the new device hooks in chain and
   flowtable to fix concurrent netlink dump traversal.

5) Add a new hook transaction object to track device hook deletions.
   The current approach moves device hooks to be deleted around during
   the preparation phase, this breaks concurrent RCU reader via netlink
   dump. This new hook transaction is combined with NFT_HOOK_REMOVE
   flag to annotate hooks for removal in the preparation phase.

6) xt_policy inbound policy check in strict mode can lead to
   out-of-bound access of the secpath array due to incorrect.
   The iteration over the secpath needs to be reversed in the inbound
   to check for the human readable policy, expecting inner in first
   position and outer in second position, the secpath from inbound
   actually stores outer in first position then in second position.
   From Jiexun Wang.

7) Fix possible zero shift in nft_bitwise triggering UBSAN splat,
   reject zero shift from control plane, from Kai Ma.

8) Replace simple_strtoul() in the conntrack SIP helper since it relies
   on nul-terminated strings. From Florian Westphal.

* tag 'nf-26-04-28' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
  netfilter: nf_conntrack_sip: don't use simple_strtoul
  netfilter: reject zero shift in nft_bitwise
  netfilter: xt_policy: fix strict mode inbound policy matching
  netfilter: nf_tables: add hook transactions for device deletions
  netfilter: nf_tables: join hook list via splice_list_rcu() in commit phase
  rculist: add list_splice_rcu() for private lists
  netfilter: nf_tables: use list_del_rcu for netlink hooks
  netfilter: arp_tables: fix IEEE1394 ARP payload parsing
====================

Link: https://patch.msgid.link/20260428095840.51961-1-pablo@netfilter.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-28 17:41:06 -07:00
Altan Hacigumus
2b9f6f7065 tcp: make probe0 timer handle expired user timeout
tcp_clamp_probe0_to_user_timeout() computes remaining time in jiffies
using subtraction with an unsigned lvalue.  If elapsed probing time
exceeds the configured TCP_USER_TIMEOUT, the underflow yields a large
value.

This ends up re-arming the probe timer for a full backoff interval
instead of expiring immediately, delaying connection teardown beyond
the configured timeout.

Fix this by preventing underflow so user-set timeout expiration is
handled correctly without extending the probe timer.

Fixes: 344db93ae3 ("tcp: make TCP_USER_TIMEOUT accurate for zero window probes")
Link: https://lore.kernel.org/r/20260414013634.43997-1-ahacigu.linux@gmail.com
Signed-off-by: Altan Hacigumus <ahacigu.linux@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260424014639.54110-1-ahacigu.linux@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-27 19:16:07 -07:00
Kuniyuki Iwashima
b3b6babf47 ipmr: Free mr_table after RCU grace period.
With CONFIG_IP_MROUTE_MULTIPLE_TABLES=n, ipmr_fib_lookup()
does not check if net->ipv4.mrt is NULL.

Since default_device_exit_batch() is called after ->exit_rtnl(),
a device could receive IGMP packets and access net->ipv4.mrt
during/after ipmr_rules_exit_rtnl().

If ipmr_rules_exit_rtnl() had already cleared it and freed the
memory, the access would trigger null-ptr-deref or use-after-free.

Let's fix it by using RCU helper and free mrt after RCU grace
period.

In addition, check_net(net) is added to mroute_clean_tables()
and ipmr_cache_unresolved() to synchronise via mfc_unres_lock.
This prevents ipmr_cache_unresolved() from putting skb into
c->_c.mfc_un.unres.unresolved after mroute_clean_tables()
purges it.

For the same reason, timer_shutdown_sync() is moved after
mroute_clean_tables().

Since rhltable_destroy() holds mutex internally, rcu_work is
used, and it is placed as the first member because rcu_head
must be placed within <4K offset.  mr_table is alraedy 3864
bytes without rcu_work.

Note that IP6MR is not yet converted to ->exit_rtnl(), so this
change is not needed for now but will be.

Fixes: b22b018674 ("ipmr: Convert ipmr_net_exit_batch() to ->exit_rtnl().")
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260423053456.4097409-1-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-27 18:46:17 -07:00
Linus Torvalds
64edfa6506 Merge tag 'net-deletions' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking deletions from Jakub Kicinski:
 "Delete some obsolete networking code

  Old code like amateur radio and NFC have long been a burden to core
  networking developers. syzbot loves to find bugs in BKL-era code, and
  noobs try to fix them.

  If we want to have a fighting chance of surviving the LLM-pocalypse
  this code needs to find a dedicated owner or get deleted. We've talked
  about these deletions multiple times in the past and every time
  someone wanted the code to stay. It is never very clear to me how many
  of those people actually use the code vs are just nostalgic to see it
  go. Amateur radio did have occasional users (or so I think) but most
  users switched to user space implementations since its all super slow
  stuff. Nobody stepped up to maintain the kernel code.

  We were lucky enough to find someone who wants to help with NFC so
  we're giving that a chance. Let's try to put the rest of this code
  behind us"

* tag 'net-deletions' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next:
  drivers: net: 8390: wd80x3: Remove this driver
  drivers: net: 8390: ultra: Remove this driver
  drivers: net: 8390: AX88190: Remove this driver
  drivers: net: fujitsu: fmvj18x: Remove this driver
  drivers: net: smsc: smc91c92: Remove this driver
  drivers: net: smsc: smc9194: Remove this driver
  drivers: net: amd: nmclan: Remove this driver
  drivers: net: amd: lance: Remove this driver
  drivers: net: 3com: 3c589: Remove this driver
  drivers: net: 3com: 3c574: Remove this driver
  drivers: net: 3com: 3c515: Remove this driver
  drivers: net: 3com: 3c509: Remove this driver
  net: packetengines: remove obsolete yellowfin driver and vendor dir
  net: packetengines: remove obsolete hamachi driver
  net: remove unused ATM protocols and legacy ATM device drivers
  net: remove ax25 and amateur radio (hamradio) subsystem
  net: remove ISDN subsystem and Bluetooth CMTP
  caif: remove CAIF NETWORK LAYER
2026-04-24 09:41:58 -07:00
Linus Torvalds
e728258deb Merge tag 'net-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull  networking fixes from Jakub Kicinski:
 "Including fixes from Netfilter.

  Steady stream of fixes. Last two weeks feel comparable to the two
  weeks before the merge window. Lots of AI-aided bug discovery. A newer
  big source is Sashiko/Gemini (Roman Gushchin's system), which points
  out issues in existing code during patch review (maybe 25% of fixes
  here likely originating from Sashiko). Nice thing is these are often
  fixed by the respective maintainers, not drive-bys.

  Current release - new code bugs:

   - kconfig: MDIO_PIC64HPSC should depend on ARCH_MICROCHIP

  Previous releases - regressions:

   - add async ndo_set_rx_mode and switch drivers which we promised to
     be called under the per-netdev mutex to it

   - dsa: remove duplicate netdev_lock_ops() for conduit ethtool ops

   - hv_sock: report EOF instead of -EIO for FIN

   - vsock/virtio: fix MSG_PEEK calculation on bytes to copy

  Previous releases - always broken:

   - ipv6: fix possible UAF in icmpv6_rcv()

   - icmp: validate reply type before using icmp_pointers

   - af_unix: drop all SCM attributes for SOCKMAP

   - netfilter: fix a number of bugs in the osf (OS fingerprinting)

   - eth: intel: fix timestamp interrupt configuration for E825C

  Misc:

   - bunch of data-race annotations"

* tag 'net-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (148 commits)
  rxrpc: Fix error handling in rxgk_extract_token()
  rxrpc: Fix re-decryption of RESPONSE packets
  rxrpc: Fix rxrpc_input_call_event() to only unshare DATA packets
  rxrpc: Fix missing validation of ticket length in non-XDR key preparsing
  rxgk: Fix potential integer overflow in length check
  rxrpc: Fix conn-level packet handling to unshare RESPONSE packets
  rxrpc: Fix potential UAF after skb_unshare() failure
  rxrpc: Fix rxkad crypto unalignment handling
  rxrpc: Fix memory leaks in rxkad_verify_response()
  net: rds: fix MR cleanup on copy error
  m68k: mvme147: Make me the maintainer
  net: txgbe: fix firmware version check
  selftests/bpf: check epoll readiness during reuseport migration
  tcp: call sk_data_ready() after listener migration
  vhost_net: fix sleeping with preempt-disabled in vhost_net_busy_poll()
  ipv6: Cap TLV scan in ip6_tnl_parse_tlv_enc_lim
  tipc: fix double-free in tipc_buf_append()
  llc: Return -EINPROGRESS from llc_ui_connect()
  ipv4: icmp: validate reply type before using icmp_pointers
  selftests/net: packetdrill: cover RFC 5961 5.2 challenge ACK on both edges
  ...
2026-04-23 16:50:42 -07:00
Zhenzhong Wu
3864c6ba1e tcp: call sk_data_ready() after listener migration
When inet_csk_listen_stop() migrates an established child socket from
a closing listener to another socket in the same SO_REUSEPORT group,
the target listener gets a new accept-queue entry via
inet_csk_reqsk_queue_add(), but that path never notifies the target
listener's waiters. A nonblocking accept() still works because it
checks the queue directly, but poll()/epoll_wait() waiters and
blocking accept() callers can also remain asleep indefinitely.

Call READ_ONCE(nsk->sk_data_ready)(nsk) after a successful migration
in inet_csk_listen_stop().

However, after inet_csk_reqsk_queue_add() succeeds, the ref acquired
in reuseport_migrate_sock() is effectively transferred to
nreq->rsk_listener. Another CPU can then dequeue nreq via accept()
or listener shutdown, hit reqsk_put(), and drop that listener ref.
Since listeners are SOCK_RCU_FREE, wrap the post-queue_add()
dereferences of nsk in rcu_read_lock()/rcu_read_unlock(), which also
covers the existing sock_net(nsk) access in that path.

The reqsk_timer_handler() path does not need the same changes for two
reasons: half-open requests become readable only after the final ACK,
where tcp_child_process() already wakes the listener; and once nreq is
visible via inet_ehash_insert(), the success path no longer touches
nsk directly.

Fixes: 54b92e8419 ("tcp: Migrate TCP_ESTABLISHED/TCP_SYN_RECV sockets in accept queues.")
Cc: stable@vger.kernel.org
Suggested-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Signed-off-by: Zhenzhong Wu <jt26wzz@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260422024554.130346-2-jt26wzz@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-23 11:54:43 -07:00
Ruide Cao
67bf002a2d ipv4: icmp: validate reply type before using icmp_pointers
Extended echo replies use ICMP_EXT_ECHOREPLY as the outbound reply type.
That value is outside the range covered by icmp_pointers[], which only
describes the traditional ICMP types up to NR_ICMP_TYPES.

Avoid consulting icmp_pointers[] for reply types outside that range, and
use array_index_nospec() for the remaining in-range lookup. Normal ICMP
replies keep their existing behavior unchanged.

Fixes: d329ea5bd8 ("icmp: add response to RFC 8335 PROBE messages")
Cc: stable@kernel.org
Reported-by: Yuan Tan <yuantan098@gmail.com>
Reported-by: Yifan Wu <yifanwucs@gmail.com>
Reported-by: Juefei Pu <tomapufckgml@gmail.com>
Reported-by: Xin Liu <bird@lzu.edu.cn>
Signed-off-by: Ruide Cao <caoruide123@gmail.com>
Signed-off-by: Ren Wei <n05ec@lzu.edu.cn>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/0dace90c01a5978e829ca741ef684dbd7304ce62.1776628519.git.caoruide123@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-23 11:40:08 -07:00
Jiayuan Chen
42726ec644 tcp: send a challenge ACK on SEG.ACK > SND.NXT
RFC 5961 Section 5.2 validates an incoming segment's ACK value
against the range [SND.UNA - MAX.SND.WND, SND.NXT] and states:

  "All incoming segments whose ACK value doesn't satisfy the above
   condition MUST be discarded and an ACK sent back."

Commit 354e4aa391 ("tcp: RFC 5961 5.2 Blind Data Injection Attack
Mitigation") opted Linux into this mitigation and implements the
challenge ACK on the lower side (SEG.ACK < SND.UNA - MAX.SND.WND),
but the symmetric upper side (SEG.ACK > SND.NXT) still takes the
pre-RFC-5961 path and silently returns
SKB_DROP_REASON_TCP_ACK_UNSENT_DATA, even though RFC 793 Section 3.9
(now RFC 9293 Section 3.10.7.4) has always required:

  "If the ACK acknowledges something not yet sent (SEG.ACK > SND.NXT)
   then send an ACK, drop the segment, and return."

Complete the mitigation by sending a challenge ACK on that branch,
reusing the existing tcp_send_challenge_ack() path which already
enforces the per-socket RFC 5961 Section 7 rate limit via
__tcp_oow_rate_limited().  FLAG_NO_CHALLENGE_ACK is honoured for
symmetry with the lower-edge case.

Update the existing tcp_ts_recent_invalid_ack.pkt selftest, which
drives this exact path, to consume the new challenge ACK.

Fixes: 354e4aa391 ("tcp: RFC 5961 5.2 Blind Data Injection Attack Mitigation")
Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260422123605.320000-2-jiayuan.chen@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-23 11:04:00 -07:00
Jakub Kicinski
dd8d4bc28a net: remove ax25 and amateur radio (hamradio) subsystem
Remove the amateur radio (AX.25, NET/ROM, ROSE) protocol implementation
and all associated hamradio device drivers from the kernel tree.
This set of protocols has long been a huge bug/syzbot magnet,
and since nobody stepped up to help us deal with the influx
of the AI-generated bug reports we need to move it out of tree
to protect our sanity.

The code is moved to an out-of-tree repo:
https://github.com/linux-netdev/mod-orphan
if it's cleaned up and reworked there we can accept it back.

Minimal stub headers are kept for include/net/ax25.h (AX25_P_IP,
AX25_ADDR_LEN, ax25_address) and include/net/rose.h (ROSE_ADDR_LEN)
so that the conditional integration code in arp.c and tun.c continues
to compile and work when the out-of-tree modules are loaded.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Stephen Hemminger <stephen@networkplumber.org>
Acked-by: Carlos Bilbao <carlos.bilbao@kernel.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Acked-by: Toke Høiland-Jørgensen <toke@toke.dk>
Link: https://patch.msgid.link/20260421021824.1293976-1-kuba@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-04-23 10:24:02 -07:00
Pablo Neira Ayuso
1e8e3f449b netfilter: arp_tables: fix IEEE1394 ARP payload parsing
Weiming Shi says:

"arp_packet_match() unconditionally parses the ARP payload assuming two
hardware addresses are present (source and target). However,
IPv4-over-IEEE1394 ARP (RFC 2734) omits the target hardware address
field, and arp_hdr_len() already accounts for this by returning a
shorter length for ARPHRD_IEEE1394 devices.

As a result, on IEEE1394 interfaces arp_packet_match() advances past a
nonexistent target hardware address and reads the wrong bytes for both
the target device address comparison and the target IP address. This
causes arptables rules to match against garbage data, leading to
incorrect filtering decisions: packets that should be accepted may be
dropped and vice versa.

The ARP stack in net/ipv4/arp.c (arp_create and arp_process) already
handles this correctly by skipping the target hardware address for
ARPHRD_IEEE1394. Apply the same pattern to arp_packet_match()."

Mangle the original patch to always return 0 (no match) in case user
matches on the target hardware address which is never present in
IEEE1394.

Note that this returns 0 (no match) for either normal and inverse match
because matching in the target hardware address in ARPHRD_IEEE1394 has
never been supported by arptables. This is intentional, matching on the
target hardware address should never evaluate true for ARPHRD_IEEE1394.

Moreover, adjust arpt_mangle to drop the packet too as AI suggests:

In arpt_mangle, the logic assumes a standard ARP layout. Because
IEEE1394 (FireWire) omits the target hardware address, the linear
pointer arithmetic miscalculates the offset for the target IP address.
This causes mangling operations to write to the wrong location, leading
to packet corruption. To ensure safety, this patch drops packets
(NF_DROP) when mangling is requested for these fields on IEEE1394
devices, as the current implementation cannot correctly map the FireWire
ARP payload.

This omits both mangling target hardware and IP address. Even if IP
address mangling should be possible in IEEE1394, this would require
to adjust arpt_mangle offset calculation, which has never been
supported.

Based on patch from Weiming Shi <bestswngs@gmail.com>.

Fixes: 6752c8db8e ("firewire net, ipv4 arp: Extend hardware address and remove driver-level packet inspection.")
Reported-by: Xiang Mei <xmei5@asu.edu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-04-21 12:44:39 +02:00
Pablo Neira Ayuso
6eda0d771f netfilter: nat: use kfree_rcu to release ops
Florian Westphal says:

"Historically this is not an issue, even for normal base hooks: the data
path doesn't use the original nf_hook_ops that are used to register the
callbacks.

However, in v5.14 I added the ability to dump the active netfilter
hooks from userspace.

This code will peek back into the nf_hook_ops that are available
at the tail of the pointer-array blob used by the datapath.

The nat hooks are special, because they are called indirectly from
the central nat dispatcher hook. They are currently invisible to
the nfnl hook dump subsystem though.

But once that changes the nat ops structures have to be deferred too."

Update nf_nat_register_fn() to deal with partial exposition of the hooks
from error path which can be also an issue for nfnetlink_hook.

Fixes: e2cf17d377 ("netfilter: add new hook nfnl subsystem")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-04-20 23:45:41 +02:00
Michael Bommarito
ec54093e6a xfrm: ah: account for ESN high bits in async callbacks
AH allocates its temporary auth/ICV layout differently when ESN is enabled:
the async ahash setup appends a 4-byte seqhi slot before the ICV or
auth_data area, but the async completion callbacks still reconstruct the
temporary layout as if seqhi were absent.

With an async AH implementation selected, that makes AH copy or compare
the wrong bytes on both the IPv4 and IPv6 paths. In UML repro on IPv4 AH
with ESN and forced async hmac(sha1), ping fails with 100% packet loss,
and the callback logs show the pre-fix drift:

  ah4 output_done: esn=1 err=0 icv_off=20 expected_off=24
  ah4 input_done: esn=1 auth_off=20 expected_auth_off=24 icv_off=32 expected_icv_off=36

Reconstruct the callback-side layout the same way the setup path built it
by skipping the ESN seqhi slot before locating the saved auth_data or ICV.
Per RFC 4302, the ESN high-order 32 bits participate in the AH ICV
computation, so the async callbacks must account for the seqhi slot.

Post-fix, the same IPv4 AH+ESN+forced-async-hmac(sha1) UML repro shows
the corrected offset (ah4 output_done: esn=1 err=0 icv_off=24
expected_off=24) and ping succeeds; net/ipv4/ah4.o and net/ipv6/ah6.o
build clean at W=1. IPv6 AH+ESN was not exercised at runtime, and the
change has not been tested against a real async hardware AH engine.

Fixes: d4d573d033 ("{IPv4,xfrm} Add ESN support for AH egress part")
Fixes: d8b2a8600b ("{IPv4,xfrm} Add ESN support for AH ingress part")
Fixes: 26dd70c3fa ("{IPv6,xfrm} Add ESN support for AH egress part")
Fixes: 8d6da6f325 ("{IPv6,xfrm} Add ESN support for AH ingress part")
Cc: stable@vger.kernel.org
Assisted-by: Codex:gpt-5-4
Assisted-by: Claude:claude-opus-4-7
Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2026-04-20 09:28:34 +02:00
Eric Dumazet
9e89b9d03a tcp: annotate data-races around tp->plb_rehash
tcp_get_timestamping_opt_stats() intentionally runs lockless, we must
add READ_ONCE() and WRITE_ONCE() annotations to keep KCSAN happy.

Fixes: 29c1c44646 ("tcp: add u32 counter in tcp_sock and an SNMP counter for PLB")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260416200319.3608680-15-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-18 11:10:14 -07:00
Eric Dumazet
3a63b3d160 tcp: annotate data-races around (tp->write_seq - tp->snd_nxt)
tcp_get_timestamping_opt_stats() intentionally runs lockless, we must
add READ_ONCE() annotations to keep KCSAN happy.

WRITE_ONCE() annotations are already present.

Fixes: e08ab0b377 ("tcp: add bytes not sent to SCM_TIMESTAMPING_OPT_STATS")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260416200319.3608680-14-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-18 11:10:13 -07:00
Eric Dumazet
71c675358b tcp: annotate data-races around tp->timeout_rehash
tcp_get_timestamping_opt_stats() intentionally runs lockless, we must
add READ_ONCE() and WRITE_ONCE() annotations to keep KCSAN happy.

Fixes: 32efcc06d2 ("tcp: export count for rehash attempts")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260416200319.3608680-13-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-18 11:10:13 -07:00
Eric Dumazet
290b693ce7 tcp: annotate data-races around tp->srtt_us
tcp_get_timestamping_opt_stats() intentionally runs lockless, we must
add READ_ONCE() and WRITE_ONCE() annotations to keep KCSAN happy.

Fixes: e8bd8fca67 ("tcp: add SRTT to SCM_TIMESTAMPING_OPT_STATS")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260416200319.3608680-12-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-18 11:10:13 -07:00
Eric Dumazet
62585690e6 tcp: annotate data-races around tp->reord_seen
tcp_get_timestamping_opt_stats() intentionally runs lockless, we must
add READ_ONCE() and WRITE_ONCE() annotations to keep KCSAN happy.

Fixes: 7ec65372ca ("tcp: add stat of data packet reordering events")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260416200319.3608680-11-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-18 11:10:13 -07:00
Eric Dumazet
a984705ca8 tcp: annotate data-races around tp->dsack_dups
tcp_get_timestamping_opt_stats() intentionally runs lockless, we must
add READ_ONCE() and WRITE_ONCE() annotations to keep KCSAN happy.

Fixes: 7e10b6554f ("tcp: add dsack blocks received stats")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260416200319.3608680-10-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-18 11:10:13 -07:00
Eric Dumazet
5efc7b9f7c tcp: annotate data-races around tp->bytes_retrans
tcp_get_timestamping_opt_stats() intentionally runs lockless, we must
add READ_ONCE() and WRITE_ONCE() annotations to keep KCSAN happy.

Fixes: fb31c9b9f6 ("tcp: add data bytes retransmitted stats")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260416200319.3608680-9-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-18 11:10:13 -07:00
Eric Dumazet
ee43e957ce tcp: annotate data-races around tp->bytes_sent
tcp_get_timestamping_opt_stats() intentionally runs lockless, we must
add READ_ONCE() and WRITE_ONCE() annotations to keep KCSAN happy.

Fixes: ba113c3aa7 ("tcp: add data bytes sent stats")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260416200319.3608680-8-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-18 11:10:12 -07:00
Eric Dumazet
124199444d tcp: add data-race annotations for TCP_NLA_SNDQ_SIZE
tcp_get_timestamping_opt_stats() intentionally runs lockless, we must
add READ_ONCE() and WRITE_ONCE() annotations to keep KCSAN happy.

Fixes: 87ecc95d81 ("tcp: add send queue size stat in SCM_TIMESTAMPING_OPT_STATS")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260416200319.3608680-7-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-18 11:10:12 -07:00
Eric Dumazet
faa886ad3c tcp: annotate data-races around tp->delivered and tp->delivered_ce
tcp_get_timestamping_opt_stats() intentionally runs lockless, we must
add READ_ONCE() and WRITE_ONCE() annotations to keep KCSAN happy.

Fixes: feb5f2ec64 ("tcp: export packets delivery info")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260416200319.3608680-6-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-18 11:10:12 -07:00