Commit Graph

84119 Commits

Author SHA1 Message Date
Ilya Maximets
aa69918bd4 openvswitch: vport: fix self-deadlock on release of tunnel ports
vports are used concurrently and protected by RCU, so netdev_put()
must happen after the RCU grace period.  So, either in an RCU call or
after the synchronize_net().  The rtnl_delete_link() must happen under
RTNL and so can't be executed in RCU context.  Calling synchronize_net()
while holding RTNL is not a good idea for performance and system
stability under load in general, so calling netdev_put() in RCU call
is the right solution here.

However,
when the device is deleted, rtnl_unlock() will call netdev_run_todo()
and block until all the references are gone.  In the current code this
means that we never reach the call_rcu() and the vport is never freed
and the reference is never released, causing a self-deadlock on device
removal.

Fix that by moving the rcu_call() before the rtnl_unlock(), so the
scheduled RCU callback will be executed when synchronize_net() is
called from the rtnl_unlock()->netdev_run_todo() while the RTNL itself
is already released.

Fixes: 6931d21f87 ("openvswitch: defer tunnel netdev_put to RCU release")
Cc: stable@vger.kernel.org
Acked-by: Eelco Chaudron <echaudro@redhat.com>
Signed-off-by: Ilya Maximets <i.maximets@ovn.org>
Acked-by: Aaron Conole <aconole@redhat.com>
Link: https://patch.msgid.link/20260430233848.440994-2-i.maximets@ovn.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-05-05 15:19:37 +02:00
Ilya Maximets
83861c48ba openvswitch: vport: fix race between tunnel creation and linking
When a tunnel vport is created it first creates the tunnel device, e.g.,
with geneve_dev_create_fb(), then it calls ovs_netdev_link() to take a
reference and link it to the device that represents openvswitch datapath.

The creation of the device is happening under RTNL, but then RTNL is
released and re-acquired to find the device by name.  It is technically
possible for the tunnel device to be re-named or deleted within that
window while RTNL is not held, and some other device created in its
place.  This will cause a non-tunnel device to be referenced in the
vport and tunnel-specific functions used on it, e.g. vxlan_get_options()
that directly casts the private netdev data into a struct vxlan_dev
causing an invalid memory access:

 BUG: KASAN: slab-use-after-free in vxlan_get_options+0x323/0x3a0
  vxlan_get_options+0x323/0x3a0
  ovs_vport_cmd_new+0x6e3/0xd30

Fix that by taking a reference to the just created device before
releasing RTNL.  This ensures that the device in the vport is always
the one that was just created.  The search by name is only needed
for a standard vport-netdev that links pre-existing devices, so that
functionality and device type checks are moved to netdev_create().

It is also awkward that ovs_netdev_link() takes ownership of the vport
and destroys it on failure.  It doesn't know the type of the port it is
dealing with, so we need to pass down the indicator that it's a tunnel,
so the link can be properly deleted on failure.

It's possible to refactor the logic to make the ovs_netdev_link() do
only the linking part and let the callers perform a proper destruction,
but it will be much more code for each legacy tunnel port type, so it
is not worth it for the bug fix.

Fixes: 614732eaa1 ("openvswitch: Use regular VXLAN net_device device")
Reported-by: Yuan Tan <tanyuan98@outlook.com>
Reported-by: Yifan Wu <yifanwucs@gmail.com>
Reported-by: Juefei Pu <tomapufckgml@gmail.com>
Reported-by: Xin Liu <bird@lzu.edu.cn>
Reported-by: Yang Yang <n05ec@lzu.edu.cn>
Signed-off-by: Ilya Maximets <i.maximets@ovn.org>
Acked-by: Eelco Chaudron <echaudro@redhat.com>
Link: https://patch.msgid.link/20260430213349.407991-1-i.maximets@ovn.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-05-05 15:14:33 +02:00
David Carlier
30cb24f97d psp: strip variable-length PSP header in psp_dev_rcv()
psp_dev_rcv() unconditionally removes a fixed PSP_ENCAP_HLEN, even
when psph->hdrlen indicates that the PSP header carries optional
fields. A frame whose PSP header advertises a non-zero VC or any
extension would therefore be silently mis-decapsulated: option bytes
would spill into the inner packet head and downstream parsing would
fail on a corrupted skb.

Compute the full PSP header length from psph->hdrlen, pull the
optional bytes into the linear region, and strip the whole header
when decapsulating. Optional fields (VC, ...) are still ignored,
just discarded with the rest of the header instead of leaking.
crypt_offset and the VIRT flag are intentionally not validated here
- callers know their device's PSP implementation and can decide.

Both in-tree callers gate on hardware-validated PSP, so this is a
correctness fix rather than a reachable corruption path under
current configurations.

Fixes: 0eddb8023c ("psp: provide decapsulation and receive helper for drivers")
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Daniel Zahka <daniel.zahka@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: David Carlier <devnexen@gmail.com>
Link: https://patch.msgid.link/20260502141945.14484-1-devnexen@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-04 19:25:14 -07:00
Eric Dumazet
ac0841d7d2 net: prevent possible UAF in rtnl_prop_list_size()
I was mistaken by synchronize_rcu() [1] call in netdev_name_node_alt_destroy(),
giving a false sense of RCU safety at delete times.

We have to use list_del_rcu() to not confuse potential readers
in rtnl_prop_list_size().

[1] This synchronize_rcu() call was later removed in commit 723de3ebef
("net: free altname using an RCU callback").

Fixes: 9f30831390 ("net: add rcu safety to rtnl_prop_list_size()")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260502124102.499204-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-04 19:24:27 -07:00
Matthieu Baerts (NGI0)
70ece9d702 mptcp: sockopt: increase seq in mptcp_setsockopt_all_sf
mptcp_setsockopt_all_sf() was missing a call to sockopt_seq_inc(). This
is required not to cause missing synchronization for newer subflows
created later on.

This helper is called each time a socket option is set on subflows, and
future ones will need to inherit this option after their creation.

Fixes: 51c5fd09e1 ("mptcp: add TCP_MAXSEG sockopt support")
Cc: stable@vger.kernel.org
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20260501-net-mptcp-misc-fixes-7-1-rc3-v1-4-b70118df778e@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-04 19:20:50 -07:00
Paolo Abeni
6254a16d6f mptcp: fix rx timestamp corruption on fastopen
The skb cb offset containing the timestamp presence flag is cleared
before loading such information. Cache such value before MPTCP CB
initialization.

Fixes: 36b122baf6 ("mptcp: add subflow_v(4,6)_send_synack()")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20260501-net-mptcp-misc-fixes-7-1-rc3-v1-3-b70118df778e@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-04 19:20:50 -07:00
Shardul Bankar
a6da02d4c0 mptcp: use MPTCP_RST_EMPTCP for ACK HMAC validation failure
When HMAC validation fails on a received ACK + MP_JOIN in
subflow_syn_recv_sock(), the subflow is reset with reason
MPTCP_RST_EPROHIBIT ("Administratively prohibited"). This is
incorrect: HMAC validation failure is an MPTCP protocol-level
error, not an administrative policy denial.

The mirror site on the client, in subflow_finish_connect(), already
uses MPTCP_RST_EMPTCP ("MPTCP-specific error") for the same kind of
HMAC failure on the SYN/ACK + MP_JOIN. Use the same reason on the
server side for symmetry and accuracy.

Suggested-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Fixes: 443041deb5 ("mptcp: fix NULL pointer in can_accept_new_subflow")
Cc: stable@vger.kernel.org
Signed-off-by: Shardul Bankar <shardul.b@mpiricsoftware.com>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20260501-net-mptcp-misc-fixes-7-1-rc3-v1-2-b70118df778e@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-04 19:20:50 -07:00
Shardul Bankar
c4a99a9219 mptcp: use MPJoinSynAckHMacFailure for SynAck HMAC failure
In subflow_finish_connect(), HMAC validation of the server's HMAC
in SYN/ACK + MP_JOIN increments MPTCP_MIB_JOINACKMAC ("HMAC was
wrong on ACK + MP_JOIN") on failure. The function processes the
SYN/ACK, not the ACK; the matching MPTCP_MIB_JOINSYNACKMAC counter
("HMAC was wrong on SYN/ACK + MP_JOIN") exists but is not
incremented anywhere in the tree.

The mirror site on the server, subflow_syn_recv_sock(), already
uses JOINACKMAC correctly for ACK HMAC failure. Use JOINSYNACKMAC
at the SYN/ACK validation site so each counter reflects the packet
whose HMAC actually failed.

Suggested-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Fixes: fc518953bc ("mptcp: add and use MIB counter infrastructure")
Cc: stable@vger.kernel.org
Signed-off-by: Shardul Bankar <shardul.b@mpiricsoftware.com>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20260501-net-mptcp-misc-fixes-7-1-rc3-v1-1-b70118df778e@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-04 19:20:50 -07:00
Eric Dumazet
059b7dbd20 vsock/virtio: fix potential unbounded skb queue
virtio_transport_inc_rx_pkt() checks vvs->rx_bytes + len > vvs->buf_alloc.

virtio_transport_recv_enqueue() skips coalescing for packets
with VIRTIO_VSOCK_SEQ_EOM.

If fed with packets with len == 0 and VIRTIO_VSOCK_SEQ_EOM,
a very large number of packets can be queued
because vvs->rx_bytes stays at 0.

Fix this by estimating the skb metadata size:

	(Number of skbs in the queue) * SKB_TRUESIZE(0)

Fixes: 0777061657 ("virtio/vsock: don't use skbuff state to account credit")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Arseniy Krasnov <AVKrasnov@sberdevices.ru>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Stefano Garzarella <sgarzare@redhat.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Cc: "Eugenio Pérez" <eperezma@redhat.com>
Cc: virtualization@lists.linux.dev
Link: https://patch.msgid.link/20260430122653.554058-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-04 19:12:37 -07:00
Breno Leitao
76b93a8107 netpoll: pass buffer size to egress_dev() to avoid MAC truncation
egress_dev() formats np->dev_mac via snprintf() but receives buf as
a bare char *, so it cannot derive the buffer size from the pointer. The
size argument was hardcoded to MAC_ADDR_STR_LEN (3 * ETH_ALEN - 1 = 17),
which is silly wrong in two ways:

 1) misleading kernel log output on the MAC-selected target path
    (np->dev_name[0] == '\0'); for example "aa:bb:cc:dd:ee:ff doesn't
    exist, aborting" was logged as "aa:bb:cc:dd:ee:f doesn't exist,
    aborting".

 2) the second argument of snprintf is the size of the buffer, not the
    size of what you want to write.

Add a bufsz parameter to egress_dev() and pass sizeof(buf) from each
caller, matching the standard snprintf() idiom and removing the
hardcoded size from the helper.

Every caller already declares "char buf[MAC_ADDR_STR_LEN + 1]" so the
formatted MAC continues to fit.

Tested by booting with
  netconsole=6665@/aa:bb:cc:dd:ee:ff,6666@10.0.0.1/00:11:22:33:44:55
on a kernel without a matching device. Pre-fix dmesg shows
"aa:bb:cc:dd:ee:f doesn't exist, aborting"; post-fix shows the full
"aa:bb:cc:dd:ee:ff doesn't exist, aborting".

Fixes: f8a10bed32 ("netconsole: allow selection of egress interface via MAC address")
Cc: stable@vger.kernel.org
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260501-netpoll_snprintf_fix-v1-1-84b0566e6597@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-04 18:37:25 -07:00
Kuniyuki Iwashima
d82ba05263 af_unix: Set gc_in_progress to true in unix_gc().
Igor Ushakov reported that unix_gc() could run with gc_in_progress
being false if the work is scheduled while running:

  Thread 1         Thread 2                     Thread 3
  --------         --------                     --------
                   unix_schedule_gc()           unix_schedule_gc()
                   `- if (!gc_in_progress)      `- if (!gc_in_progress)
                      |- gc_in_progress = true     |
                      `- queue_work()              |
  unix_gc() <----------------/                     |
  |                                                |- gc_in_progress = true
  ...                                              `- queue_work()
  |                                                       |
  `- gc_in_progress = false                               |
                                                          |
  unix_gc() <---------------------------------------------'
  |
  ... /* gc_in_progress == false */
  |
  `- gc_in_progress = false

unix_peek_fpl() relies on gc_in_progress not to confuse GC
by MSG_PEEK.

Let's set gc_in_progress to true in unix_gc().

Fixes: 8b90a9f819 ("af_unix: Run GC on only one CPU.")
Reported-by: Igor Ushakov <sysroot314@gmail.com>
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260501073945.1884564-1-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-04 18:34:45 -07:00
Jakub Kicinski
7e7be31bfd net: tls: fix silent data drop under pipe back-pressure
tls_sw_splice_read() uses len when advancing rxm->offset / rxm->full_len
after skb_splice_bits(), rather than copied (the actual number of bytes
successfully spliced into the pipe). When the destination pipe cannot
accept all the requested bytes, splice_to_pipe() returns fewer bytes
than len, and 'len - copied' of data is effectively skipped over.

Fixes: e062fe99cc ("tls: splice_read: fix accessing pre-processed records")
Link: https://patch.msgid.link/20260429222944.2139041-2-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-02 18:27:14 -07:00
Eric Dumazet
67dc6c56b8 net/sched: sch_cake: annotate data-races in cake_dump_class_stats (II)
cake_dump_class_stats() runs without qdisc spinlock being held.

In this second patch, I add READ_ONCE()/WRITE_ONCE() annotations for:

- flow->deficit
- flow->cvars.dropping
- flow->cvars.count
- flow->cvars.p_drop
- flow->cvars.blue_timer
- flow->cvars.drop_next

Fixes: 046f6fd5da ("sched: Add Common Applications Kept Enhanced (cake) qdisc")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Toke Høiland-Jørgensen <toke@toke.dk>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260430061610.3503483-3-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-02 16:59:09 -07:00
Eric Dumazet
046111a1a3 net/sched: sch_cake: annotate data-races in cake_dump_class_stats (I)
cake_dump_class_stats() runs without qdisc spinlock being held.

In this first patch, I add READ_ONCE()/WRITE_ONCE() annotations for:

- flow->head
- flow->dropped
- b->backlogs[]

Fixes: 046f6fd5da ("sched: Add Common Applications Kept Enhanced (cake) qdisc")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Toke Høiland-Jørgensen <toke@toke.dk>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260430061610.3503483-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-02 16:59:09 -07:00
Maoyi Xie
1d324c2f43 ip6_gre: Use cached t->net in ip6erspan_changelink().
After commit 5e72ce3e39 ("net: ipv6: Use link netns in newlink() of
rtnl_link_ops"), ip6erspan_newlink() correctly resolves the per-netns
ip6gre hash via link_net. ip6erspan_changelink() was not converted in
that series and still uses dev_net(dev), which diverges from the
device's creation netns after IFLA_NET_NS_FD migration.

This re-inserts the tunnel into the wrong per-netns hash. The
original netns keeps a stale entry. When that netns is later
destroyed, ip6gre_exit_rtnl_net() walks the stale entry, producing a
slab-use-after-free reported by KASAN, followed by a kernel BUG at
net/core/dev.c (LIST_POISON1) in unregister_netdevice_many_notify().

Reachable from an unprivileged user namespace (unshare --user
--map-root-user --net).

ip6gre_changelink() earlier in the same file already uses the cached
t->net; only ip6erspan_changelink() has the wrong shape.

Fixes: 2d665034f2 ("net: ip6_gre: Fix ip6erspan hlen calculation")
Cc: stable@vger.kernel.org # v5.15+
Signed-off-by: Maoyi Xie <maoyi.xie@ntu.edu.sg>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260430103318.3206018-1-maoyi.xie@ntu.edu.sg
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-02 10:36:21 -07:00
Victor Nogueria
1b9bc71153 net/sched: sch_sfb: Replace direct dequeue call with peek and qdisc_dequeue_peeked
When sfb has children (eg qfq qdisc) whose peek() callback is
qdisc_peek_dequeued(), we could get a kernel panic. When the parent of such
qdiscs (eg illustrated in patch #3 as tbf) wants to retrieve an skb from
its child (sfb in this case), it will do the following:
 1a. do a peek() - and when sensing there's an skb the child can offer, then
     - the child in this case(sfb) calls its child's (qfq) peek.
        qfq does the right thing and will return the gso_skb queue packet.
        Note: if there wasnt a gso_skb entry then qfq will store it there.
 1b. invoke a dequeue() on the child (sfb). And herein lies the problem.
     - sfb will call the child's dequeue() which will essentially just
       try to grab something of qfq's queue.

[  127.594489][  T453] KASAN: null-ptr-deref in range [0x0000000000000048-0x000000000000004f]
[  127.594741][  T453] CPU: 2 UID: 0 PID: 453 Comm: ping Not tainted 7.1.0-rc1-00035-gac961974495b-dirty #793 PREEMPT(full)
[  127.595059][  T453] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[  127.595254][  T453] RIP: 0010:qfq_dequeue+0x35c/0x1650 [sch_qfq]
[  127.595461][  T453] Code: 00 fc ff df 80 3c 02 00 0f 85 17 0e 00 00 4c 8d 73 48 48 89 9d b8 02 00 00 48 b8 00 00 00 00 00 fc ff df 4c 89 f2 48 c1 ea 03 <80> 3c 02 00 0f 85 76 0c 00 00 48 b8 00 00 00 00 00 fc ff df 4c 8b
[  127.596081][  T453] RSP: 0018:ffff88810e5af440 EFLAGS: 00010216
[  127.596337][  T453] RAX: dffffc0000000000 RBX: 0000000000000000 RCX: dffffc0000000000
[  127.596623][  T453] RDX: 0000000000000009 RSI: 0000001880000000 RDI: ffff888104fd82b0
[  127.596917][  T453] RBP: ffff888104fd8000 R08: ffff888104fd8280 R09: 1ffff110211893a3
[  127.597165][  T453] R10: 1ffff110211893a6 R11: 1ffff110211893a7 R12: 0000001880000000
[  127.597404][  T453] R13: ffff888104fd82b8 R14: 0000000000000048 R15: 0000000040000000
[  127.597644][  T453] FS:  00007fc380cbfc40(0000) GS:ffff88816f2a8000(0000) knlGS:0000000000000000
[  127.597956][  T453] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  127.598160][  T453] CR2: 00005610aa9890a8 CR3: 000000010369e000 CR4: 0000000000750ef0
[  127.598390][  T453] PKRU: 55555554
[  127.598509][  T453] Call Trace:
[  127.598629][  T453]  <TASK>
[  127.598718][  T453]  ? mark_held_locks+0x40/0x70
[  127.598890][  T453]  ? srso_alias_return_thunk+0x5/0xfbef5
[  127.599053][  T453]  sfb_dequeue+0x88/0x4d0
[  127.599174][  T453]  ? ktime_get+0x137/0x230
[  127.599328][  T453]  ? srso_alias_return_thunk+0x5/0xfbef5
[  127.599480][  T453]  ? qdisc_peek_dequeued+0x7b/0x350 [sch_qfq]
[  127.599670][  T453]  ? srso_alias_return_thunk+0x5/0xfbef5
[  127.599831][  T453]  tbf_dequeue+0x6b1/0x1098 [sch_tbf]
[  127.599988][  T453]  __qdisc_run+0x169/0x1900

The right thing to do in #1b is to grab the skb off gso_skb queue.
This patchset fixes that issue by changing #1b to use qdisc_dequeue_peeked()
method instead.

Fixes: e13e02a3c6 ("net_sched: SFB flow scheduler")
Signed-off-by: Victor Nogueria <victor@mojatatu.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260430152957.194015-3-jhs@mojatatu.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-02 10:20:56 -07:00
Jamal Hadi Salim
458d561527 net/sched: sch_red: Replace direct dequeue call with peek and qdisc_dequeue_peeked
When red qdisc has children (eg qfq qdisc) whose peek() callback is
qdisc_peek_dequeued(), we could get a kernel panic. When the parent of such
qdiscs (eg illustrated in patch #3 as tbf) wants to retrieve an skb from
its child (red in this case), it will do the following:
 1a. do a peek() - and when sensing there's an skb the child can offer, then
     - the child in this case(red) calls its child's (qfq) peek.
        qfq does the right thing and will return the gso_skb queue packet.
        Note: if there wasnt a gso_skb entry then qfq will store it there.
 1b. invoke a dequeue() on the child (red). And herein lies the problem.
     - red will call the child's dequeue() which will essentially just
       try to grab something of qfq's queue.

[   78.667668][  T363] KASAN: null-ptr-deref in range [0x0000000000000048-0x000000000000004f]
[   78.667927][  T363] CPU: 1 UID: 0 PID: 363 Comm: ping Not tainted 7.1.0-rc1-00033-g46f74a3f7d57-dirty #790 PREEMPT(full)
[   78.668263][  T363] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   78.668486][  T363] RIP: 0010:qfq_dequeue+0x446/0xc90 [sch_qfq]
[   78.668718][  T363] Code: 54 c0 e8 dd 90 00 f1 48 c7 c7 e0 03 54 c0 48 89 de e8 ce 90 00 f1 48 8d 7b 48 b8 ff ff 37 00 48 89 fa 48 c1 e0 2a 48 c1 ea 03 <80> 3c 02 00 74 05 e8 ef a1 e1 f1 48 8b 7b 48 48 8d 54 24 58 48 8d
[   78.669312][  T363] RSP: 0018:ffff88810de573e0 EFLAGS: 00010216
[   78.669533][  T363] RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000
[   78.669790][  T363] RDX: 0000000000000009 RSI: 0000000000000004 RDI: 0000000000000048
[   78.670044][  T363] RBP: ffff888110dc4000 R08: ffffffffb1b0885a R09: fffffbfff6ba9078
[   78.670297][  T363] R10: 0000000000000003 R11: ffff888110e31c80 R12: 0000001880000000
[   78.670560][  T363] R13: ffff888110dc4150 R14: ffff888110dc42b8 R15: 0000000000000200
[   78.670814][  T363] FS:  00007f66a8f09c40(0000) GS:ffff888163428000(0000) knlGS:0000000000000000
[   78.671110][  T363] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   78.671324][  T363] CR2: 000055db4c6a30a8 CR3: 000000010da67000 CR4: 0000000000750ef0
[   78.671585][  T363] PKRU: 55555554
[   78.671713][  T363] Call Trace:
[   78.671843][  T363]  <TASK>
[   78.671936][  T363]  ? __pfx_qfq_dequeue+0x10/0x10 [sch_qfq]
[   78.672148][  T363]  ? __pfx__printk+0x10/0x10
[   78.672322][  T363]  ? srso_alias_return_thunk+0x5/0xfbef5
[   78.672496][  T363]  ? lockdep_hardirqs_on_prepare+0xa8/0x1a0
[   78.672706][  T363]  ? srso_alias_return_thunk+0x5/0xfbef5
[   78.672875][  T363]  ? trace_hardirqs_on+0x19/0x1a0
[   78.673047][  T363]  red_dequeue+0x65/0x270 [sch_red]
[   78.673217][  T363]  ? srso_alias_return_thunk+0x5/0xfbef5
[   78.673385][  T363]  tbf_dequeue.cold+0xb0/0x70c [sch_tbf]
[   78.673566][  T363]  __qdisc_run+0x169/0x1900

The right thing to do in #1b is to grab the skb off gso_skb queue.
This patchset fixes that issue by changing #1b to use qdisc_dequeue_peeked()
method instead.

Fixes: 77be155cba ("pkt_sched: Add peek emulation for non-work-conserving qdiscs.")
Reported-by: Manas <ghandatmanas@gmail.com>
Reported-by: Rakshit Awasthi <rakshitawasthi17@gmail.com>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260430152957.194015-2-jhs@mojatatu.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-02 10:20:55 -07:00
Sagarika Sharma
4bc852006b ipv6: update route serial number on NETDEV_CHANGE
When using IPv6 ECMP routes, if a netdev listed as a nexthop experiences
a carrier change event (e.g., a bond device generating a NETDEV_CHANGE
event after its slaves go linkdown), established connections utilizing
that nexthop fail to fail over to other available nexthops. Instead,
these connections stall or drop.

This happens because the IPv6 FIB code does not invalidate the socket's
cached destination when a NETDEV_CHANGE event occurs. While
fib6_ifdown() correctly marks the nexthop with RTNH_F_LINKDOWN, it
leaves the route's serial number unchanged. As a result, sockets with a
previously cached dst do not realize the route is no longer viable and
continue to try using the non-functional nexthop.

This behavior contrasts with IPv4, which actively flushes cached
destinations on a NETDEV_CHANGE event (see fib_netdev_event() in
net/ipv4/fib_frontend.c).

Fix this by updating the route serial number in fib6_ifdown() when
setting RTNH_F_LINKDOWN. This invalidates stale cached destinations,
forcing sockets to perform a new route lookup and fail over to a
functioning nexthop.

Fixes: 51ebd31815 ("ipv6: add support of equal cost multipath (ECMP)")
Signed-off-by: Sagarika Sharma <sharmasagarika@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260430200909.527827-2-sharmasagarika@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-01 17:58:44 -07:00
Eric Dumazet
6d4106e8df net/sched: sch_pie: annotate more data-races in pie_dump_stats()
My prior patch missed few READ_ONCE()/WRITE_ONCE() annotations.

Fixes: 5154561d9b ("net/sched: sch_pie: annotate data-races in pie_dump_stats()")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260430080056.35104-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-01 17:54:57 -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
Kai Zen
4b9e327991 net: rtnetlink: zero ifla_vf_broadcast to avoid stack infoleak in rtnl_fill_vfinfo
rtnl_fill_vfinfo() declares struct ifla_vf_broadcast on the stack
without initialisation:

	struct ifla_vf_broadcast vf_broadcast;

The struct contains a single fixed 32-byte field:

	/* include/uapi/linux/if_link.h */
	struct ifla_vf_broadcast {
		__u8 broadcast[32];
	};

The function then copies dev->broadcast into it using dev->addr_len
as the length:

	memcpy(vf_broadcast.broadcast, dev->broadcast, dev->addr_len);

On Ethernet devices (the overwhelming majority of SR-IOV NICs)
dev->addr_len is 6, so only the first 6 bytes of broadcast[] are
written. The remaining 26 bytes retain whatever was previously on
the kernel stack. The full struct is then handed to userspace via:

	nla_put(skb, IFLA_VF_BROADCAST,
		sizeof(vf_broadcast), &vf_broadcast)

leaking up to 26 bytes of uninitialised kernel stack per VF per
RTM_GETLINK request, repeatable.

The other vf_* structs in the same function are explicitly zeroed
for exactly this reason - see the memset() calls for ivi,
vf_vlan_info, node_guid and port_guid a few lines above.
vf_broadcast was simply missed when it was added.

Reachability: any unprivileged local process can open AF_NETLINK /
NETLINK_ROUTE without capabilities and send RTM_GETLINK with an
IFLA_EXT_MASK attribute carrying RTEXT_FILTER_VF. The kernel walks
each VF and emits IFLA_VF_BROADCAST, leaking 26 bytes of stack per
VF per request. Stack residue at this call site can include return
addresses and transient sensitive data; KASAN with stack
instrumentation, or KMSAN, will flag the nla_put() when reproduced.

Zero the on-stack struct before the partial memcpy, matching the
existing pattern used for the other vf_* structs in the same
function.

Fixes: 75345f888f ("ipoib: show VF broadcast address")
Cc: stable@vger.kernel.org
Signed-off-by: Kai Zen <kai.aizen.dev@gmail.com>
Link: https://patch.msgid.link/3c506e8f936e52b57620269b55c348af05d413a2.1777557228.git.kai.aizen.dev@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-01 17:04:28 -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
2ab02ac411 Merge tag 'nf-26-05-01' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf
Pablo Neira Ayuso says:

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

The following batch contains Netfilter fixes for net:

1) Replace skb_try_make_writable() by skb_ensure_writable() in
   nft_fwd_netdev and the flowtable to deal with uncloned packets
   having their network header in paged fragments.

2) Drop packet if output device does not exist and ensure sufficient
   headroom in nft_fwd_netdev before transmitting the skb.

3) Use the existing dup recursion counter in nft_fwd_netdev for the
   neigh_xmit variant, from Weiming Shi.

4) Add .check_hooks interface to x_tables to detach the control plane
   hook check based on the match/target configuration. Then, update
   nft_compat to use .check_hooks from .validate path, this fixes a
   lack of hook validation for several match/targets.

5) Fix incorrect .usersize in xt_CT, from Florian Westphal.

6) Fix a memleak with netdev tables in dormant state,
   from Florian Westphal.

7) Several patches to check if the packet is a fragment, then skip
   layer 4 inspection, for x_tables and nf_tables; as well as common
   nf_socket infrastructure. The xt_hashlimit match drops fragments
   to stay consistent with the existing approach when failing to parse
   the layer 4 protocol header.

8) Ensure sufficient headroom in the flowtable before transmitting
   the skb.

9) Fix the flowtable inline vlan approach for double-tagged vlan:
   Reverse the iteration over .encap[] since it represents the
   encapsulation as seen from the ingress path. Postpone pushing
   layer 2 header so output device is available to calculate needed
   headroom. Finally, add and use nf_flow_vlan_push() to fix it.

10) Fix flowtable inline pppoe with GSO packets. Moreover, use
    FLOW_OFFLOAD_XMIT_DIRECT to fill up destination hardware
    address since neighbour cache does not exist in pppoe.

11) Use skb_pull_rcsum() to decapsulate vlan and pppoe headers, for
    double-tagged vlan in particular this should provide some benefits
    in certain scenarios.

More notes regarding 9-11):

- sashiko is also signalling to use it for IPIP headers, but that needs
  more adjustments such setting skb->protocol after removing the IPIP
  header, will follow up in a separated patch.
- I plan to submit selftests to cover double-tagged-vlan. As for pppoe,
  it should be possible but that would mandate a few userspace dependencies.
  This has been semi-automatically  tested by me and reporters describing
  broken double-vlan-tagged and pppoe currently in the flowtable.

* tag 'nf-26-05-01' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
  netfilter: flowtable: use skb_pull_rcsum() to pop vlan/pppoe header
  netfilter: flowtable: fix inline pppoe encapsulation in xmit path
  netfilter: flowtable: fix inline vlan encapsulation in xmit path
  netfilter: flowtable: ensure sufficient headroom in xmit path
  netfilter: xtables: fix L4 header parsing for non-first fragments
  netfilter: nf_tables: skip L4 header parsing for non-first fragments
  netfilter: nf_socket: skip socket lookup for non-first fragments
  netfilter: nf_tables: fix netdev hook allocation memleak with dormant tables
  netfilter: xt_CT: fix usersize for v1 and v2 revision
  netfilter: nft_compat: run xt_check_hooks_{match,target}() from .validate
  netfilter: x_tables: add .check_hooks to matches and targets
  netfilter: nft_fwd_netdev: use recursion counter in neigh egress path
  netfilter: nft_fwd_netdev: add device and headroom validate with neigh forwarding
  netfilter: replace skb_try_make_writable() by skb_ensure_writable()
====================

Link: https://patch.msgid.link/20260501122237.296262-1-pablo@netfilter.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-01 16:45:42 -07:00
Pablo Neira Ayuso
baa3c65435 netfilter: flowtable: use skb_pull_rcsum() to pop vlan/pppoe header
This adjusts the checksum, if required, after pulling the layer 2
header, either the pppoe header or the inner vlan header in the
double-tagged vlan packets.

Fixes: 4cd91f7c29 ("netfilter: flowtable: add vlan support")
Fixes: 72efd585f7 ("netfilter: flowtable: add pppoe support")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-05-01 12:39:23 +02:00
Daniel Borkmann
3744b0964d ipv6: Implement limits on extension header parsing
ipv6_{skip_exthdr,find_hdr}() and ip6_{tnl_parse_tlv_enc_lim,
protocol_deliver_rcu}() iterate over IPv6 extension headers until they
find a non-extension-header protocol or run out of packet data. The
loops have no iteration counter, relying solely on the packet length
to bound them. For a crafted packet with 8-byte extension headers
filling a 64KB jumbogram, this means a worst case of up to ~8k
iterations with a skb_header_pointer call each. ipv6_skip_exthdr(),
for example, is used where it parses the inner quoted packet inside
an incoming ICMPv6 error:

  - icmpv6_rcv
    - checksum validation
    - case ICMPV6_DEST_UNREACH
      - icmpv6_notify
        - pskb_may_pull()       <- pull inner IPv6 header
        - ipv6_skip_exthdr()    <- iterates here
        - pskb_may_pull()
        - ipprot->err_handler() <- sk lookup

The per-iteration cost of ipv6_skip_exthdr itself is generally
light, but skb_header_pointer becomes more costly on reassembled
packets: the first ~1232 bytes of the inner packet are in the skb's
linear area, but the remaining ~63KB are in the frag_list where
skb_copy_bits is needed to read data.

Initially, the idea was to add a configurable limit via a new
sysctl knob with default 8, in line with knobs from commit
47d3d7ac65 ("ipv6: Implement limits on Hop-by-Hop and Destination
options"), but two reasons eventually argued against it:

- It adds to UAPI that needs to be maintained forever, and
  upcoming work is restricting extension header ordering anyway,
  leaving little reason for another sysctl knob
- exthdrs_core.c is always built-in even when CONFIG_IPV6=n,
  where struct net has no .ipv6 member, so the read site would
  need an ifdef'd fallback to a constant anyway

Therefore, just use a constant (IP6_MAX_EXT_HDRS_CNT). All four
extension header walking functions are now bound by this limit.

Note that the check in ip6_protocol_deliver_rcu() happens right
before the goto resubmit, such that we don't have to have a test
for ipv6_ext_hdr() in the fast-path.

There's an ongoing IETF draft-iurman-6man-eh-occurrences to enforce
IPv6 extension headers ordering and occurrence. The latter also
discusses security implications. As per RFC8200 section 4.1, the
occurrence rules for extension headers provide a practical upper
bound which is 8. In order to be conservative, let's define
IP6_MAX_EXT_HDRS_CNT as 12 to leave enough room for quirky setups.
In the unlikely event that this is still not enough, then we might
need to reconsider a sysctl.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Justin Iurman <justin.iurman@gmail.com>
Link: https://patch.msgid.link/20260429154648.809751-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-30 17:21:45 -07:00
Pablo Neira Ayuso
69c54f80f4 netfilter: flowtable: fix inline pppoe encapsulation in xmit path
Address two issues in the inline pppoe encapsulation:

- Add needs_gso_segment flag to segment PPPoE packets in software
  given that there is no GSO support for this.

- Use FLOW_OFFLOAD_XMIT_DIRECT since neighbour cache is not available
  in point-to-point device, use the hardware address that is obtained
  via flowtable path discovery (ie. fill_forward_path).

Fixes: 18d27bed08 ("netfilter: flowtable: inline pppoe encapsulation in xmit path")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-05-01 01:24:01 +02:00
Pablo Neira Ayuso
a177ae30f7 netfilter: flowtable: fix inline vlan encapsulation in xmit path
Several issues in the inline vlan support:

- The layer 2 encapsulation representation in the tuple takes encap[0] as
  the outer header and encap[1] as the inner header as seen from the ingress
  path. Reverse the encap loop to push first the inner then the outer vlan
  header.

- Postpone pushing the layer 2 header once destination device is known.
  This allows to calculate the needed hearoom via LL_RESERVED_SPACE to
  accommodate the layer 2 headers.

- Add and use nf_flow_vlan_push() as suggested by Eric Woudstra, this
  is a simplified version of skb_vlan_push() for egress path only.

Fixes: c653d5a78f ("netfilter: flowtable: inline vlan encapsulation in xmit path")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-05-01 01:23:47 +02:00
Jeremy Kerr
7687297106 net: mctp: test: Use dev_direct_xmit for TX to our test device
In our test cases, we typically feed a packet sequence into the routing
code, then inspect the device's TXed skbs to assert specific behaviours.

Using dev_queue_xmit() for our TX path introduces a fair bit of
complexity between the test packet sequence and the test device's
ndo_start_xmit callback; which may mean that the skbs have not hit the
device at the point we're inspecting the TXed skb list.

Use dev_direct_xmit instead, as we want a direct a path as possible
here, and the test dev does not need any queueing, scheduling or flow
control.

Fixes: 6ab578739a ("net: mctp: test: move TX packetqueue from dst to dev")
Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202604281320.525eee17-lkp@intel.com
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260429-dev-mctp-test-fixes-v1-2-1127b7425809@codeconstruct.com.au
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-30 13:36:47 -07:00
Jeremy Kerr
18ed60e33e net: mctp: test: use a zeroed struct sockaddr_mctp
Invalid sockaddr padding will cause bind() to fail; ensure we have a
zeroed address in the testcase.

Fixes: 0d8647bc74 ("net: mctp: don't require a route for null-EID ingress")
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260429-dev-mctp-test-fixes-v1-1-1127b7425809@codeconstruct.com.au
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-30 13:36:47 -07:00
Pablo Neira Ayuso
ef4f741e86 netfilter: flowtable: ensure sufficient headroom in xmit path
Check for headroom and call skb_expand_head() like in the IP output
path to ensure there is sufficient headroom for the mac header when
forwarding this packet as suggested by sashiko.

Fixes: b5964aac51 ("netfilter: flowtable: consolidate xmit path")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-04-30 17:59:01 +02:00
Fernando Fernandez Mancera
952e121c96 netfilter: xtables: fix L4 header parsing for non-first fragments
Multiple targets and matches relies on L4 header to operate. For
fragmented packets, every fragment carries the transport protocol
identifier, but only the first fragment contains the L4 header.

As the 'raw' table can be configured to run at priority -450 (before
defragmentation at -400), the target/match can be reached before
reassembly. In this case, non-first fragments have their payload
incorrectly parsed as a TCP/UDP header. This would be of course a
misconfiguration scenario. In most of the cases this just lead to a
unreliable behavior for fragmented traffic.

Add a fragment check to ensure target/match only evaluates unfragmented
packets or the first fragment in the stream.

Fixes: 902d6a4c2a ("netfilter: nf_defrag: Skip defrag if NOTRACK is set")
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
Fernando Fernandez Mancera
009d203e56 netfilter: nf_tables: skip L4 header parsing for non-first fragments
The tproxy, osf and exthdr (SCTP) expressions rely on the presence of
transport layer headers to perform socket lookups, fingerprint matching,
or chunk extraction. For fragmented packets, while the IP protocol
remains constant across all fragments, only the first fragment contains
the actual L4 header.

The expressions could be attached to a chain with a priority lower than
-400, bypassing defragmentation. Or could be used in stateless
environments where defragmentation is not happening at all.  This could
result in garbage data being used for the matching.

Add a check for pkt->fragoff so only unfragmented packets or the first
fragment is processed.

Fixes: 133dc203d7 ("netfilter: nft_exthdr: Support SCTP chunks")
Fixes: 4ed8eb6570 ("netfilter: nf_tables: Add native tproxy support")
Fixes: b96af92d6e ("netfilter: nf_tables: implement Passive OS fingerprint module in nft_osf")
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
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
Paolo Abeni
1e01abec85 net/sched: cls_flower: revert unintended changes
While applying the blamed commit 4ca07b9239 ("net: mctp i2c: check
length before marking flow active"), I unintentionally included
unrelated and unacceptable changes.

Revert them.

Fixes: 4ca07b9239 ("net: mctp i2c: check length before marking flow active")
Reported-by: Jeremy Kerr <jk@codeconstruct.com.au>
Closes: https://lore.kernel.org/netdev/bd8704fe0bd53e278add5cde4873256656623e2e.camel@codeconstruct.com.au/
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Link: https://patch.msgid.link/043026a53ff84da88b17648c4b0d17f0331749cb.1777447863.git.pabeni@redhat.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-04-30 13:47:01 +02:00
Jakub Kicinski
58689498ca net: tls: fix strparser anchor skb leak on offload RX setup failure
When tls_set_device_offload_rx() fails at tls_dev_add(), the error path
calls tls_sw_free_resources_rx() to clean up the SW context that was
initialized by tls_set_sw_offload(). This function calls
tls_sw_release_resources_rx() (which stops the strparser via
tls_strp_stop()) and tls_sw_free_ctx_rx() (which kfrees the context),
but never frees the anchor skb that was allocated by alloc_skb(0) in
tls_strp_init().

Note that tls_sw_free_resources_rx() is exclusively used for this
"failed to start offload" code path, there's no other caller.

The leak did not exist before commit 84c61fe1a7 ("tls: rx: do not use
the standard strparser"), because the standard strparser doesn't try
to pre-allocate an skb.

The normal close path in tls_sk_proto_close() handles cleanup by calling
tls_sw_strparser_done() (which calls tls_strp_done()) after dropping
the socket lock, because tls_strp_done() does cancel_work_sync() and
the strparser work handler takes the socket lock.

Fixes: 84c61fe1a7 ("tls: rx: do not use the standard strparser")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Link: https://patch.msgid.link/20260428231559.1358502-1-kuba@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-04-30 13:38:29 +02:00
Florian Westphal
63bac02786 netfilter: nf_tables: fix netdev hook allocation memleak with dormant tables
sashiko says:
 could the related code in __nf_tables_abort() leak the struct nft_hook objects when the table is dormant?

 In __nf_tables_abort(), when rolling back a NEWCHAIN transaction that
 updates hooks, the code conditionally unregisters and frees the hooks only
 if the table is not dormant [..]
            if (!(table->flags & NFT_TABLE_F_DORMANT)) {
                nft_netdev_unregister_hooks(net,
                                            &nft_trans_chain_hooks(trans),
                                            true);
            }
            ...
            nft_trans_destroy(trans);

Unfortunately netdev family mixes hook registration and allocation.
Push table struct down and only check for the flag to unregister.

Fixes: 216e7bf740 ("netfilter: nf_tables: skip netdev hook unregistration if table is dormant")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-04-30 08:03:22 +02:00
Florian Westphal
8bedb6c469 netfilter: xt_CT: fix usersize for v1 and v2 revision
While resurrecting the conntrack-tool test cases I found following bug:
In:
iptables -I OUTPUT -t raw -p 13 -j CT --timeout test-generic
Out:
[0:0] -A OUTPUT -p 13 -j CT --timeout test

Data after first four bytes of the timeout policy name is never
copied to userspace because its treated as kernel-only.

Fixes: ec23189049 ("xtables: extend matches and targets with .usersize")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-04-30 08:03:22 +02:00
Pablo Neira Ayuso
2f768d638d netfilter: nft_compat: run xt_check_hooks_{match,target}() from .validate
Several matches and one target check that the hook is correct from
checkentry(), however, the basechain is only available from
nft_table_validate().

This patch uses xt_check_hooks_{match,target}() from the nft_compat
expression .validate path.

This patch sets the table in the nft_ctx struct in nft_table_validate()
which is required by this patch.

Based on patch from Florian Westphal.

Fixes: 0ca743a559 ("netfilter: nf_tables: add compatibility layer for x_tables")
Reported-by: Xiang Mei <xmei5@asu.edu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-04-30 08:03:22 +02:00
Pablo Neira Ayuso
6813985ca4 netfilter: x_tables: add .check_hooks to matches and targets
Add a new .check_hooks interface for checking if the match/target is
used from the validate hook according to its configuration.

Move existing conditional hook check based on the match/target
configuration from .checkentry to .check_hooks for the following
matches/targets:

- addrtype
- devgroup
- physdev
- policy
- set
- TCPMSS
- SET

This is a preparation patch to fix nft_compat, not functional changes
are intended.

Based on patch from Florian Westphal.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-04-30 08:03:22 +02:00
Hasan Basbunar
5ef343614d page_pool: fix memory-provider leak in page_pool_create_percpu() error path
When page_pool_create_percpu() fails on page_pool_list(), it falls
through to its err_uninit: label, which calls page_pool_uninit().
At that point page_pool_init() has already taken two references
when the user requested PP_FLAG_ALLOW_UNREADABLE_NETMEM:

	pool->mp_ops->init(pool)
	static_branch_inc(&page_pool_mem_providers);

Neither is undone by page_pool_uninit(); both are only undone by
__page_pool_destroy() (success-side teardown). The error path
therefore leaks the per-provider reference taken by mp_ops->init
(io_zcrx_ifq->refs in the io_uring zcrx provider, the dmabuf
binding refcount in the devmem provider) plus one increment of
the page_pool_mem_providers static branch on every failure of
xa_alloc_cyclic() inside page_pool_list().

The leaked io_zcrx_ifq->refs in turn pins everything
io_zcrx_ifq_free() would release on cleanup: ifq->user (uid),
ifq->mm_account (mmdrop), ifq->dev (device refcount),
ifq->netdev_tracker (netdev refcount), and the rbuf region.
The leaked static branch increment forces all subsequent
page_pool_alloc_netmems() and page_pool_return_page() callers to
take the slow mp_ops branch for the lifetime of the kernel.

Reachable via the io_uring zcrx path:

	io_uring_register(IORING_REGISTER_ZCRX_IFQ)  /* CAP_NET_ADMIN */
	  -> __io_uring_register
	  -> io_register_zcrx
	  -> zcrx_register_netdev
	  -> netif_mp_open_rxq
	  -> driver ndo_queue_mem_alloc
	  -> page_pool_create_percpu
	    -> page_pool_init succeeds (mp_ops->init runs, branch++)
	    -> page_pool_list fails (xa_alloc_cyclic -ENOMEM)
	    -> goto err_uninit         <-- leak

The same shape applies to the devmem dmabuf provider via
mp_dmabuf_devmem_init()/mp_dmabuf_devmem_destroy().

Restore the cleanup symmetry by moving the mp_ops->destroy() and
static_branch_dec() calls out of __page_pool_destroy() and into
page_pool_uninit(), so page_pool_uninit() is again the strict
inverse of page_pool_init(). page_pool_uninit() has only two
callers (the err_uninit: path and __page_pool_destroy()), so this
preserves the single-call invariant on the success path while
fixing the err path. The error path of page_pool_init() itself
still skips the mp_ops cleanup correctly: mp_ops->init is the
last action that takes a reference before page_pool_init() returns
0, so when it returns an error neither the refcount nor the static
branch has been touched.

Triggering the bug requires xa_alloc_cyclic() to fail with -ENOMEM,
which under normal GFP_KERNEL retry behaviour is rare. It is
deterministic under CONFIG_FAULT_INJECTION with fail_page_alloc /
xa fault injection, or under sustained memory pressure. The leak
is silent: there is no warning, and the released kernel build
continues running with a permanently-incremented static branch.

Fixes: 0f92140468 ("memory-provider: dmabuf devmem memory provider")
Signed-off-by: Hasan Basbunar <basbunarhasan@gmail.com>
Link: https://patch.msgid.link/20260428170739.34881-1-basbunarhasan@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-29 19:11:49 -07:00
Hamza Mahfooz
b31681206e hv_sock: fix ARM64 support
VMBUS ring buffers must be page aligned. Therefore, the current value of
24K presents a challenge on ARM64 kernels (with 64K pages). So, use
VMBUS_RING_SIZE() to ensure they are always aligned and large enough to
hold all of the relevant data.

Cc: stable@vger.kernel.org
Fixes: 77ffe33363 ("hv_sock: use HV_HYP_PAGE_SIZE for Hyper-V communication")
Tested-by: Dexuan Cui <decui@microsoft.com>
Reviewed-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com>
Acked-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://patch.msgid.link/20260428125339.13963-1-hamzamahfooz@linux.microsoft.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-29 17:30:45 -07:00
Jakub Kicinski
735a309b4b net: add net_iov_init() and use it to initialize ->page_type
Commit db359fccf2 ("mm: introduce a new page type for page pool in
page type") added a page_type field to struct net_iov at the same
offset as struct page::page_type, so that page_pool_set_pp_info() can
call __SetPageNetpp() uniformly on both pages and net_iovs.

The page-type API requires the field to hold the UINT_MAX "no type"
sentinel before a type can be set; for real struct page that invariant
is established by the page allocator on free. struct net_iov is not
allocated through the page allocator, so the field is left as zero
(io_uring zcrx, which uses __GFP_ZERO) or as slab garbage (devmem,
which uses kvmalloc_objs() without zeroing). When the page pool then
calls page_pool_set_pp_info() on a freshly-bound niov,
__SetPageNetpp()'s VM_BUG_ON_PAGE(page->page_type != UINT_MAX) fires
and the kernel BUGs. Triggered in selftests by io_uring zcrx setup
through the fbnic queue restart path:

 kernel BUG at ./include/linux/page-flags.h:1062!
 RIP: 0010:page_pool_set_pp_info (./include/linux/page-flags.h:1062
                                  net/core/page_pool.c:716)
 Call Trace:
  <TASK>
  net_mp_niov_set_page_pool (net/core/page_pool.c:1360)
  io_pp_zc_alloc_netmems (io_uring/zcrx.c:1089 io_uring/zcrx.c:1110)
  fbnic_fill_bdq (./include/net/page_pool/helpers.h:160
                  drivers/net/ethernet/meta/fbnic/fbnic_txrx.c:906)
  __fbnic_nv_restart (drivers/net/ethernet/meta/fbnic/fbnic_txrx.c:2470
                      drivers/net/ethernet/meta/fbnic/fbnic_txrx.c:2874)
  fbnic_queue_start (drivers/net/ethernet/meta/fbnic/fbnic_txrx.c:2903)
  netdev_rx_queue_reconfig (net/core/netdev_rx_queue.c:137)
  __netif_mp_open_rxq (net/core/netdev_rx_queue.c:234)
  io_register_zcrx (io_uring/zcrx.c:818 io_uring/zcrx.c:903)
  __io_uring_register (io_uring/register.c:931)
  __do_sys_io_uring_register (io_uring/register.c:1029)
  do_syscall_64 (arch/x86/entry/syscall_64.c:63
                 arch/x86/entry/syscall_64.c:94)
  </TASK>

The same path is reachable through devmem dmabuf binding via
netdev_nl_bind_rx_doit() -> net_devmem_bind_dmabuf_to_queue().

Add a net_iov_init() helper that stamps ->owner, ->type and the
->page_type sentinel, and use it from both the devmem and io_uring
zcrx niov init loops.

Fixes: db359fccf2 ("mm: introduce a new page type for page pool in page type")
Acked-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
Acked-by: Byungchul Park <byungchul@sk.com>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Acked-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://patch.msgid.link/20260428025320.853452-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-29 16:40:08 -07:00
Weiming Shi
1d47b55b36 netfilter: nft_fwd_netdev: use recursion counter in neigh egress path
nft_fwd_neigh can be used in egress chains (NF_NETDEV_EGRESS). When the
forwarding rule targets the same device or two devices forward to each
other, neigh_xmit() triggers dev_queue_xmit() which re-enters
nf_hook_egress(), causing infinite recursion and stack overflow.

Move the nf_get_nf_dup_skb_recursion() accessor and NF_RECURSION_LIMIT
to the shared header nf_dup_netdev.h as a static inline, so that
nft_fwd_netdev can use the recursion counter directly without exported
function call overhead. Guard neigh_xmit() with the same recursion
limit already used in nf_do_netdev_egress().

[ Updated to cache the nf_get_nf_dup_skb_recursion pointer. --pablo ]

Fixes: f87b9464d1 ("netfilter: nft_fwd_netdev: Support egress hook")
Reported-by: Xiang Mei <xmei5@asu.edu>
Signed-off-by: Weiming Shi <bestswngs@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-04-30 00:57:42 +02:00
Pablo Neira Ayuso
0a0b35f0bf netfilter: nft_fwd_netdev: add device and headroom validate with neigh forwarding
The ttl field has been decremented already and evaluation of this rule
would proceed, just drop this packet instead if there is no destination
device to forwards this packet. This is exactly what nf_dup already does
in this case.

Moreover, check for headroom and call skb_expand_head() like in the IP
output path to ensure there is sufficient headroom when forwarding this
via neigh_xmit().

Fixes: d32de98ea7 ("netfilter: nft_fwd_netdev: allow to forward packets via neighbour layer")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-04-30 00:57:42 +02:00
Pablo Neira Ayuso
1049970d75 netfilter: replace skb_try_make_writable() by skb_ensure_writable()
skb_try_make_writable() only works on clones and uncloned packets might
have their network header in paged fragments.

nft_fwd needs to work for the ingress and egress hooks, but the egress
hook where skb->data points to the mac header, use skb_network_offset()
to include the mac header. The flowtable is fine since it already uses
the transport offset.

Fixes: d32de98ea7 ("netfilter: nft_fwd_netdev: allow to forward packets via neighbour layer")
Fixes: 7d20868717 ("netfilter: nf_flow_table: move ipv4 offload hook code to nf_flow_table")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-04-30 00:57:42 +02:00
Matthieu Baerts (NGI0)
1774d3cf3c mptcp: pm: kernel: reset fullmesh counter after flush
This variable counts how many MPTCP endpoints have a 'fullmesh' flag
set. After having flushed all MPTCP endpoints, it is then needed to
reset this counter.

Without this reset, this counter exposed to the userspace is wrong, but
also non-fullmesh endpoints added after the flush will not be taken into
account to create subflows in reaction to ADD_ADDRs.

Fixes: f88191c7f3 ("mptcp: pm: in-kernel: record fullmesh endp nb")
Cc: stable@vger.kernel.org
Reported-by: Sashiko <sashiko-bot@kernel.org>
Closes: https://sashiko.dev/#/patchset/20260422-mptcp-inc-limits-v6-0-903181771530%40kernel.org?part=15
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20260427-net-mptcp-misc-fixes-7-1-rc2-v1-4-7432b7f279fa@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-28 18:36:27 -07:00
Matthieu Baerts (NGI0)
f14d6e9c36 mptcp: fastclose msk when linger time is 0
The SO_LINGER socket option has been supported for a while with MPTCP
sockets [1], but it didn't cause the equivalent of a TCP reset as
expected when enabled and its time was set to 0. This was causing some
behavioural differences with TCP where some connections were not
promptly stopped as expected.

To fix that, an extra condition is checked at close() time before
sending an MP_FASTCLOSE, the MPTCP equivalent of a TCP reset.

Note that backporting up to [1] will be difficult as more changes are
needed to be able to send MP_FASTCLOSE. It seems better to stop at [2],
which was supposed to already imitate TCP.

Validated with MPTCP packetdrill tests [3].

Fixes: 268b123874 ("mptcp: setsockopt: support SO_LINGER") [1]
Fixes: d21f834855 ("mptcp: use fastclose on more edge scenarios") [2]
Cc: stable@vger.kernel.org
Reported-by: Lance Tuller <lance@lance0.com>
Closes: https://github.com/lance0/xfr/pull/67
Link: https://github.com/multipath-tcp/packetdrill/pull/196 [3]
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20260427-net-mptcp-misc-fixes-7-1-rc2-v1-3-7432b7f279fa@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-28 18:36:27 -07:00
Gang Yan
b5c52908d5 mptcp: fix scheduling with atomic in timestamp sockopt
Using lock_sock_fast() (atomic context) around sock_set_timestamp()
and sock_set_timestamping() is unsafe, as both helpers can sleep.

Replace lock_sock_fast() with sleepable lock_sock()/release_sock()
to avoid scheduling while atomic panic.

Fixes: 9061f24bf8 ("mptcp: sockopt: propagate timestamp request to subflows")
Cc: stable@vger.kernel.org
Reported-by: Sashiko <sashiko-bot@kernel.org>
Closes: https://sashiko.dev/#/patchset/20260420093343.16443-1-gang.yan@linux.dev
Signed-off-by: Gang Yan <yangang@kylinos.cn>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20260427-net-mptcp-misc-fixes-7-1-rc2-v1-2-7432b7f279fa@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-28 18:36:27 -07:00
Gang Yan
5f95c21fc2 mptcp: sockopt: set timestamp flags on subflow socket, not msk
Both mptcp_setsockopt_sol_socket_tstamp() and
mptcp_setsockopt_sol_socket_timestamping() iterate over subflows,
acquire the subflow socket lock, but then erroneously pass the MPTCP
msk socket to sock_set_timestamp() / sock_set_timestamping() instead
of the subflow ssk. As a result, the timestamp flags are set on the
wrong socket and have no effect on the actual subflows.

Pass ssk instead of sk to both helpers.

Fixes: 9061f24bf8 ("mptcp: sockopt: propagate timestamp request to subflows")
Cc: stable@vger.kernel.org
Signed-off-by: Gang Yan <yangang@kylinos.cn>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20260427-net-mptcp-misc-fixes-7-1-rc2-v1-1-7432b7f279fa@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-28 18:36:27 -07:00
Eric Dumazet
a6c95b833d net/sched: sch_cake: annotate data-races in cake_dump_stats() (V)
cake_dump_stats() runs without qdisc spinlock being held.

In this final patch, I add READ_ONCE()/WRITE_ONCE() annotations
for cparams.target and cparams.interval.

Fixes: 046f6fd5da ("sched: Add Common Applications Kept Enhanced (cake) qdisc")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: "Toke Høiland-Jørgensen" <toke@toke.dk>
Link: https://patch.msgid.link/20260427083606.459355-6-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-28 18:27:51 -07:00