linux-toradex.git/net/sched, branch v6.15 Linux kernel for Apalis and Colibri modules sch_hfsc: Fix qlen accounting bug when using peek in hfsc_enqueue() 2025-05-22T09:16:44+00:00 Cong Wang xiyou.wangcong@gmail.com 2025-05-18T22:20:37+00:00 3f981138109f63232a5fb7165938d4c945cc1b9d When enqueuing the first packet to an HFSC class, hfsc_enqueue() calls the child qdisc's peek() operation before incrementing sch->q.qlen and sch->qstats.backlog. If the child qdisc uses qdisc_peek_dequeued(), this may trigger an immediate dequeue and potential packet drop. In such cases, qdisc_tree_reduce_backlog() is called, but the HFSC qdisc's qlen and backlog have not yet been updated, leading to inconsistent queue accounting. This can leave an empty HFSC class in the active list, causing further consequences like use-after-free. This patch fixes the bug by moving the increment of sch->q.qlen and sch->qstats.backlog before the call to the child qdisc's peek() operation. This ensures that queue length and backlog are always accurate when packet drops or dequeues are triggered during the peek. Fixes: 12d0ad3be9c3 ("net/sched/sch_hfsc.c: handle corner cases where head may change invalidating calculated deadline") Reported-by: Mingi Cho <mincho@theori.io> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20250518222038.58538-2-xiyou.wangcong@gmail.com Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> 
When enqueuing the first packet to an HFSC class, hfsc_enqueue() calls the
child qdisc's peek() operation before incrementing sch->q.qlen and
sch->qstats.backlog. If the child qdisc uses qdisc_peek_dequeued(), this may
trigger an immediate dequeue and potential packet drop. In such cases,
qdisc_tree_reduce_backlog() is called, but the HFSC qdisc's qlen and backlog
have not yet been updated, leading to inconsistent queue accounting. This
can leave an empty HFSC class in the active list, causing further
consequences like use-after-free.

This patch fixes the bug by moving the increment of sch->q.qlen and
sch->qstats.backlog before the call to the child qdisc's peek() operation.
This ensures that queue length and backlog are always accurate when packet
drops or dequeues are triggered during the peek.

Fixes: 12d0ad3be9c3 ("net/sched/sch_hfsc.c: handle corner cases where head may change invalidating calculated deadline")
Reported-by: Mingi Cho <mincho@theori.io>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250518222038.58538-2-xiyou.wangcong@gmail.com
Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
net_sched: Flush gso_skb list too during ->change() 2025-05-09T11:34:38+00:00 Cong Wang xiyou.wangcong@gmail.com 2025-05-07T04:35:58+00:00 2d3cbfd6d54a2c39ce3244f33f85c595844bd7b8 Previously, when reducing a qdisc's limit via the ->change() operation, only the main skb queue was trimmed, potentially leaving packets in the gso_skb list. This could result in NULL pointer dereference when we only check sch->limit against sch->q.qlen. This patch introduces a new helper, qdisc_dequeue_internal(), which ensures both the gso_skb list and the main queue are properly flushed when trimming excess packets. All relevant qdiscs (codel, fq, fq_codel, fq_pie, hhf, pie) are updated to use this helper in their ->change() routines. Fixes: 76e3cc126bb2 ("codel: Controlled Delay AQM") Fixes: 4b549a2ef4be ("fq_codel: Fair Queue Codel AQM") Fixes: afe4fd062416 ("pkt_sched: fq: Fair Queue packet scheduler") Fixes: ec97ecf1ebe4 ("net: sched: add Flow Queue PIE packet scheduler") Fixes: 10239edf86f1 ("net-qdisc-hhf: Heavy-Hitter Filter (HHF) qdisc") Fixes: d4b36210c2e6 ("net: pkt_sched: PIE AQM scheme") Reported-by: Will <willsroot@protonmail.com> Reported-by: Savy <savy@syst3mfailure.io> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
Previously, when reducing a qdisc's limit via the ->change() operation, only
the main skb queue was trimmed, potentially leaving packets in the gso_skb
list. This could result in NULL pointer dereference when we only check
sch->limit against sch->q.qlen.

This patch introduces a new helper, qdisc_dequeue_internal(), which ensures
both the gso_skb list and the main queue are properly flushed when trimming
excess packets. All relevant qdiscs (codel, fq, fq_codel, fq_pie, hhf, pie)
are updated to use this helper in their ->change() routines.

Fixes: 76e3cc126bb2 ("codel: Controlled Delay AQM")
Fixes: 4b549a2ef4be ("fq_codel: Fair Queue Codel AQM")
Fixes: afe4fd062416 ("pkt_sched: fq: Fair Queue packet scheduler")
Fixes: ec97ecf1ebe4 ("net: sched: add Flow Queue PIE packet scheduler")
Fixes: 10239edf86f1 ("net-qdisc-hhf: Heavy-Hitter Filter (HHF) qdisc")
Fixes: d4b36210c2e6 ("net: pkt_sched: PIE AQM scheme")
Reported-by: Will <willsroot@protonmail.com>
Reported-by: Savy <savy@syst3mfailure.io>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
sch_htb: make htb_deactivate() idempotent 2025-05-05T20:51:32+00:00 Cong Wang xiyou.wangcong@gmail.com 2025-04-28T23:29:54+00:00 3769478610135e82b262640252d90f6efb05be71 Alan reported a NULL pointer dereference in htb_next_rb_node() after we made htb_qlen_notify() idempotent. It turns out in the following case it introduced some regression: htb_dequeue_tree(): |-> fq_codel_dequeue() |-> qdisc_tree_reduce_backlog() |-> htb_qlen_notify() |-> htb_deactivate() |-> htb_next_rb_node() |-> htb_deactivate() For htb_next_rb_node(), after calling the 1st htb_deactivate(), the clprio[prio]->ptr could be already set to NULL, which means htb_next_rb_node() is vulnerable here. For htb_deactivate(), although we checked qlen before calling it, in case of qlen==0 after qdisc_tree_reduce_backlog(), we may call it again which triggers the warning inside. To fix the issues here, we need to: 1) Make htb_deactivate() idempotent, that is, simply return if we already call it before. 2) Make htb_next_rb_node() safe against ptr==NULL. Many thanks to Alan for testing and for the reproducer. Fixes: 5ba8b837b522 ("sch_htb: make htb_qlen_notify() idempotent") Reported-by: Alan J. Wylie <alan@wylie.me.uk> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Link: https://patch.msgid.link/20250428232955.1740419-2-xiyou.wangcong@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Alan reported a NULL pointer dereference in htb_next_rb_node()
after we made htb_qlen_notify() idempotent.

It turns out in the following case it introduced some regression:

htb_dequeue_tree():
  |-> fq_codel_dequeue()
    |-> qdisc_tree_reduce_backlog()
      |-> htb_qlen_notify()
        |-> htb_deactivate()
  |-> htb_next_rb_node()
  |-> htb_deactivate()

For htb_next_rb_node(), after calling the 1st htb_deactivate(), the
clprio[prio]->ptr could be already set to  NULL, which means
htb_next_rb_node() is vulnerable here.

For htb_deactivate(), although we checked qlen before calling it, in
case of qlen==0 after qdisc_tree_reduce_backlog(), we may call it again
which triggers the warning inside.

To fix the issues here, we need to:

1) Make htb_deactivate() idempotent, that is, simply return if we
   already call it before.
2) Make htb_next_rb_node() safe against ptr==NULL.

Many thanks to Alan for testing and for the reproducer.

Fixes: 5ba8b837b522 ("sch_htb: make htb_qlen_notify() idempotent")
Reported-by: Alan J. Wylie <alan@wylie.me.uk>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Link: https://patch.msgid.link/20250428232955.1740419-2-xiyou.wangcong@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net_sched: qfq: Fix double list add in class with netem as child qdisc 2025-04-28T22:55:07+00:00 Victor Nogueira victor@mojatatu.com 2025-04-25T22:07:08+00:00 f139f37dcdf34b67f5bf92bc8e0f7f6b3ac63aa4 As described in Gerrard's report [1], there are use cases where a netem child qdisc will make the parent qdisc's enqueue callback reentrant. In the case of qfq, there won't be a UAF, but the code will add the same classifier to the list twice, which will cause memory corruption. This patch checks whether the class was already added to the agg->active list (cl_is_active) before doing the addition to cater for the reentrant case. [1] https://lore.kernel.org/netdev/CAHcdcOm+03OD2j6R0=YHKqmy=VgJ8xEOKuP6c7mSgnp-TEJJbw@mail.gmail.com/ Fixes: 37d9cf1a3ce3 ("sched: Fix detection of empty queues in child qdiscs") Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Victor Nogueira <victor@mojatatu.com> Link: https://patch.msgid.link/20250425220710.3964791-5-victor@mojatatu.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
As described in Gerrard's report [1], there are use cases where a netem
child qdisc will make the parent qdisc's enqueue callback reentrant.
In the case of qfq, there won't be a UAF, but the code will add the same
classifier to the list twice, which will cause memory corruption.

This patch checks whether the class was already added to the agg->active
list (cl_is_active) before doing the addition to cater for the reentrant
case.

[1] https://lore.kernel.org/netdev/CAHcdcOm+03OD2j6R0=YHKqmy=VgJ8xEOKuP6c7mSgnp-TEJJbw@mail.gmail.com/

Fixes: 37d9cf1a3ce3 ("sched: Fix detection of empty queues in child qdiscs")
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Victor Nogueira <victor@mojatatu.com>
Link: https://patch.msgid.link/20250425220710.3964791-5-victor@mojatatu.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net_sched: ets: Fix double list add in class with netem as child qdisc 2025-04-28T22:55:06+00:00 Victor Nogueira victor@mojatatu.com 2025-04-25T22:07:07+00:00 1a6d0c00fa07972384b0c308c72db091d49988b6 As described in Gerrard's report [1], there are use cases where a netem child qdisc will make the parent qdisc's enqueue callback reentrant. In the case of ets, there won't be a UAF, but the code will add the same classifier to the list twice, which will cause memory corruption. In addition to checking for qlen being zero, this patch checks whether the class was already added to the active_list (cl_is_active) before doing the addition to cater for the reentrant case. [1] https://lore.kernel.org/netdev/CAHcdcOm+03OD2j6R0=YHKqmy=VgJ8xEOKuP6c7mSgnp-TEJJbw@mail.gmail.com/ Fixes: 37d9cf1a3ce3 ("sched: Fix detection of empty queues in child qdiscs") Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Victor Nogueira <victor@mojatatu.com> Link: https://patch.msgid.link/20250425220710.3964791-4-victor@mojatatu.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
As described in Gerrard's report [1], there are use cases where a netem
child qdisc will make the parent qdisc's enqueue callback reentrant.
In the case of ets, there won't be a UAF, but the code will add the same
classifier to the list twice, which will cause memory corruption.

In addition to checking for qlen being zero, this patch checks whether
the class was already added to the active_list (cl_is_active) before
doing the addition to cater for the reentrant case.

[1] https://lore.kernel.org/netdev/CAHcdcOm+03OD2j6R0=YHKqmy=VgJ8xEOKuP6c7mSgnp-TEJJbw@mail.gmail.com/

Fixes: 37d9cf1a3ce3 ("sched: Fix detection of empty queues in child qdiscs")
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Victor Nogueira <victor@mojatatu.com>
Link: https://patch.msgid.link/20250425220710.3964791-4-victor@mojatatu.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net_sched: hfsc: Fix a UAF vulnerability in class with netem as child qdisc 2025-04-28T22:55:06+00:00 Victor Nogueira victor@mojatatu.com 2025-04-25T22:07:06+00:00 141d34391abbb315d68556b7c67ad97885407547 As described in Gerrard's report [1], we have a UAF case when an hfsc class has a netem child qdisc. The crux of the issue is that hfsc is assuming that checking for cl->qdisc->q.qlen == 0 guarantees that it hasn't inserted the class in the vttree or eltree (which is not true for the netem duplicate case). This patch checks the n_active class variable to make sure that the code won't insert the class in the vttree or eltree twice, catering for the reentrant case. [1] https://lore.kernel.org/netdev/CAHcdcOm+03OD2j6R0=YHKqmy=VgJ8xEOKuP6c7mSgnp-TEJJbw@mail.gmail.com/ Fixes: 37d9cf1a3ce3 ("sched: Fix detection of empty queues in child qdiscs") Reported-by: Gerrard Tai <gerrard.tai@starlabs.sg> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Victor Nogueira <victor@mojatatu.com> Link: https://patch.msgid.link/20250425220710.3964791-3-victor@mojatatu.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
As described in Gerrard's report [1], we have a UAF case when an hfsc class
has a netem child qdisc. The crux of the issue is that hfsc is assuming
that checking for cl->qdisc->q.qlen == 0 guarantees that it hasn't inserted
the class in the vttree or eltree (which is not true for the netem
duplicate case).

This patch checks the n_active class variable to make sure that the code
won't insert the class in the vttree or eltree twice, catering for the
reentrant case.

[1] https://lore.kernel.org/netdev/CAHcdcOm+03OD2j6R0=YHKqmy=VgJ8xEOKuP6c7mSgnp-TEJJbw@mail.gmail.com/

Fixes: 37d9cf1a3ce3 ("sched: Fix detection of empty queues in child qdiscs")
Reported-by: Gerrard Tai <gerrard.tai@starlabs.sg>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Victor Nogueira <victor@mojatatu.com>
Link: https://patch.msgid.link/20250425220710.3964791-3-victor@mojatatu.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net_sched: drr: Fix double list add in class with netem as child qdisc 2025-04-28T22:55:06+00:00 Victor Nogueira victor@mojatatu.com 2025-04-25T22:07:05+00:00 f99a3fbf023e20b626be4b0f042463d598050c9a As described in Gerrard's report [1], there are use cases where a netem child qdisc will make the parent qdisc's enqueue callback reentrant. In the case of drr, there won't be a UAF, but the code will add the same classifier to the list twice, which will cause memory corruption. In addition to checking for qlen being zero, this patch checks whether the class was already added to the active_list (cl_is_active) before adding to the list to cover for the reentrant case. [1] https://lore.kernel.org/netdev/CAHcdcOm+03OD2j6R0=YHKqmy=VgJ8xEOKuP6c7mSgnp-TEJJbw@mail.gmail.com/ Fixes: 37d9cf1a3ce3 ("sched: Fix detection of empty queues in child qdiscs") Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Victor Nogueira <victor@mojatatu.com> Link: https://patch.msgid.link/20250425220710.3964791-2-victor@mojatatu.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
As described in Gerrard's report [1], there are use cases where a netem
child qdisc will make the parent qdisc's enqueue callback reentrant.
In the case of drr, there won't be a UAF, but the code will add the same
classifier to the list twice, which will cause memory corruption.

In addition to checking for qlen being zero, this patch checks whether the
class was already added to the active_list (cl_is_active) before adding
to the list to cover for the reentrant case.

[1] https://lore.kernel.org/netdev/CAHcdcOm+03OD2j6R0=YHKqmy=VgJ8xEOKuP6c7mSgnp-TEJJbw@mail.gmail.com/

Fixes: 37d9cf1a3ce3 ("sched: Fix detection of empty queues in child qdiscs")
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Victor Nogueira <victor@mojatatu.com>
Link: https://patch.msgid.link/20250425220710.3964791-2-victor@mojatatu.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net_sched: hfsc: Fix a potential UAF in hfsc_dequeue() too 2025-04-24T00:16:50+00:00 Cong Wang xiyou.wangcong@gmail.com 2025-04-17T18:47:31+00:00 6ccbda44e2cc3d26fd22af54c650d6d5d801addf Similarly to the previous patch, we need to safe guard hfsc_dequeue() too. But for this one, we don't have a reliable reproducer. Fixes: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 ("Linux-2.6.12-rc2") Reported-by: Gerrard Tai <gerrard.tai@starlabs.sg> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com> Link: https://patch.msgid.link/20250417184732.943057-3-xiyou.wangcong@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Similarly to the previous patch, we need to safe guard hfsc_dequeue()
too. But for this one, we don't have a reliable reproducer.

Fixes: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 ("Linux-2.6.12-rc2")
Reported-by: Gerrard Tai <gerrard.tai@starlabs.sg>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://patch.msgid.link/20250417184732.943057-3-xiyou.wangcong@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net_sched: hfsc: Fix a UAF vulnerability in class handling 2025-04-24T00:16:50+00:00 Cong Wang xiyou.wangcong@gmail.com 2025-04-17T18:47:30+00:00 3df275ef0a6ae181e8428a6589ef5d5231e58b5c This patch fixes a Use-After-Free vulnerability in the HFSC qdisc class handling. The issue occurs due to a time-of-check/time-of-use condition in hfsc_change_class() when working with certain child qdiscs like netem or codel. The vulnerability works as follows: 1. hfsc_change_class() checks if a class has packets (q.qlen != 0) 2. It then calls qdisc_peek_len(), which for certain qdiscs (e.g., codel, netem) might drop packets and empty the queue 3. The code continues assuming the queue is still non-empty, adding the class to vttree 4. This breaks HFSC scheduler assumptions that only non-empty classes are in vttree 5. Later, when the class is destroyed, this can lead to a Use-After-Free The fix adds a second queue length check after qdisc_peek_len() to verify the queue wasn't emptied. Fixes: 21f4d5cc25ec ("net_sched/hfsc: fix curve activation in hfsc_change_class()") Reported-by: Gerrard Tai <gerrard.tai@starlabs.sg> Reviewed-by: Konstantin Khlebnikov <koct9i@gmail.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com> Link: https://patch.msgid.link/20250417184732.943057-2-xiyou.wangcong@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
This patch fixes a Use-After-Free vulnerability in the HFSC qdisc class
handling. The issue occurs due to a time-of-check/time-of-use condition
in hfsc_change_class() when working with certain child qdiscs like netem
or codel.

The vulnerability works as follows:
1. hfsc_change_class() checks if a class has packets (q.qlen != 0)
2. It then calls qdisc_peek_len(), which for certain qdiscs (e.g.,
   codel, netem) might drop packets and empty the queue
3. The code continues assuming the queue is still non-empty, adding
   the class to vttree
4. This breaks HFSC scheduler assumptions that only non-empty classes
   are in vttree
5. Later, when the class is destroyed, this can lead to a Use-After-Free

The fix adds a second queue length check after qdisc_peek_len() to verify
the queue wasn't emptied.

Fixes: 21f4d5cc25ec ("net_sched/hfsc: fix curve activation in hfsc_change_class()")
Reported-by: Gerrard Tai <gerrard.tai@starlabs.sg>
Reviewed-by: Konstantin Khlebnikov <koct9i@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://patch.msgid.link/20250417184732.943057-2-xiyou.wangcong@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Merge tag 'net-6.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2025-04-10T15:52:18+00:00 Linus Torvalds torvalds@linux-foundation.org 2025-04-10T15:52:18+00:00 ab59a8605604f71bbbc16077270dc3f39648b7fc Pull networking fixes from Paolo Abeni: "Including fixes from netfilter. Current release - regressions: - core: hold instance lock during NETDEV_CHANGE - rtnetlink: fix bad unlock balance in do_setlink() - ipv6: - fix null-ptr-deref in addrconf_add_ifaddr() - align behavior across nexthops during path selection Previous releases - regressions: - sctp: prevent transport UaF in sendmsg - mptcp: only inc MPJoinAckHMacFailure for HMAC failures Previous releases - always broken: - sched: - make ->qlen_notify() idempotent - ensure sufficient space when sending filter netlink notifications - sch_sfq: really don't allow 1 packet limit - netfilter: fix incorrect avx2 match of 5th field octet - tls: explicitly disallow disconnect - eth: octeontx2-pf: fix VF root node parent queue priority" * tag 'net-6.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (38 commits) ethtool: cmis_cdb: Fix incorrect read / write length extension selftests: netfilter: add test case for recent mismatch bug nft_set_pipapo: fix incorrect avx2 match of 5th field octet net: ppp: Add bound checking for skb data on ppp_sync_txmung net: Fix null-ptr-deref by sock_lock_init_class_and_name() and rmmod. ipv6: Align behavior across nexthops during path selection net: phy: allow MDIO bus PM ops to start/stop state machine for phylink-controlled PHY net: phy: move phy_link_change() prior to mdio_bus_phy_may_suspend() selftests/tc-testing: sfq: check that a derived limit of 1 is rejected net_sched: sch_sfq: move the limit validation net_sched: sch_sfq: use a temporary work area for validating configuration net: libwx: handle page_pool_dev_alloc_pages error selftests: mptcp: validate MPJoin HMacFailure counters mptcp: only inc MPJoinAckHMacFailure for HMAC failures rtnetlink: Fix bad unlock balance in do_setlink(). net: ethtool: Don't call .cleanup_data when prepare_data fails tc: Ensure we have enough buffer space when sending filter netlink notifications net: libwx: Fix the wrong Rx descriptor field octeontx2-pf: qos: fix VF root node parent queue index selftests: tls: check that disconnect does nothing ... 
Pull networking fixes from Paolo Abeni:
 "Including fixes from netfilter.

  Current release - regressions:

    - core: hold instance lock during NETDEV_CHANGE

    - rtnetlink: fix bad unlock balance in do_setlink()

    - ipv6:
       - fix null-ptr-deref in addrconf_add_ifaddr()
       - align behavior across nexthops during path selection

  Previous releases - regressions:

    - sctp: prevent transport UaF in sendmsg

    - mptcp: only inc MPJoinAckHMacFailure for HMAC failures

  Previous releases - always broken:

    - sched:
       - make ->qlen_notify() idempotent
       - ensure sufficient space when sending filter netlink notifications
       - sch_sfq: really don't allow 1 packet limit

    - netfilter: fix incorrect avx2 match of 5th field octet

    - tls: explicitly disallow disconnect

    - eth: octeontx2-pf: fix VF root node parent queue priority"

* tag 'net-6.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (38 commits)
  ethtool: cmis_cdb: Fix incorrect read / write length extension
  selftests: netfilter: add test case for recent mismatch bug
  nft_set_pipapo: fix incorrect avx2 match of 5th field octet
  net: ppp: Add bound checking for skb data on ppp_sync_txmung
  net: Fix null-ptr-deref by sock_lock_init_class_and_name() and rmmod.
  ipv6: Align behavior across nexthops during path selection
  net: phy: allow MDIO bus PM ops to start/stop state machine for phylink-controlled PHY
  net: phy: move phy_link_change() prior to mdio_bus_phy_may_suspend()
  selftests/tc-testing: sfq: check that a derived limit of 1 is rejected
  net_sched: sch_sfq: move the limit validation
  net_sched: sch_sfq: use a temporary work area for validating configuration
  net: libwx: handle page_pool_dev_alloc_pages error
  selftests: mptcp: validate MPJoin HMacFailure counters
  mptcp: only inc MPJoinAckHMacFailure for HMAC failures
  rtnetlink: Fix bad unlock balance in do_setlink().
  net: ethtool: Don't call .cleanup_data when prepare_data fails
  tc: Ensure we have enough buffer space when sending filter netlink notifications
  net: libwx: Fix the wrong Rx descriptor field
  octeontx2-pf: qos: fix VF root node parent queue index
  selftests: tls: check that disconnect does nothing
  ...