Commit Graph

1464667 Commits

Author SHA1 Message Date
Hyunjung Ko
f1b3416cea selftests: tc-testing: add act_ct test for malformed header handling
Add a tdc case covering the leak fixed by the previous patch.

The test attaches "action ct" to a clsact ingress chain and injects ten
IPv6 frames whose nexthdr says hop-by-hop but which carry nothing after
the 40-byte header, so ipv6_find_hdr() fails and
tcf_ct_ipv6_is_fragment() returns -EPROTO.

Before the fix act_ct returned TC_ACT_CONSUMED for these packets, so
tc_run() never reached its TC_ACT_SHOT arm and the clsact drop counter
stayed at zero while the skbs leaked. After the fix the packets are
dropped properly and the counter reflects them, which is what the test
matches on:

  before:  Sent 476 bytes 11 pkt (dropped 0, overlimits 0 requeues 0)
  after:   Sent 400 bytes 10 pkt (dropped 10, overlimits 0 requeues 0)

Signed-off-by: Hyunjung Ko <hj351016@gmail.com>
Reviewed-by: Victor Nogueira <victor@mojatatu.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://patch.msgid.link/20260806101235.809370-2-hj351016@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-10 16:37:07 -07:00
Hyunjung Ko
8a7ed56167 net/sched: act_ct: fix sk_buff leak when the header checks reject a packet
tcf_ct_handle_fragments() runs its header sanity checks before handing
anything to the defragmentation engine:

	if (family == NFPROTO_IPV4)
		err = tcf_ct_ipv4_is_fragment(skb, &frag);
	else
		err = tcf_ct_ipv6_is_fragment(skb, &frag);
	if (err || !frag)
		return err;

tcf_ct_ipv4_is_fragment() returns -EINVAL or -ENOMEM;
tcf_ct_ipv6_is_fragment() adds -EPROTO when ipv6_find_hdr() fails. None of
them frees or queues the skb, so on that path the caller still owns it.

tcf_ct_act() however funnels every non-zero return into the
ownership-transfer exit:

	err = tcf_ct_handle_fragments(net, skb, family, p->zone, &defrag);
	if (err)
		goto out_frag;
	...
out_frag:
	if (err != -EINPROGRESS)
		tcf_action_inc_drop_qstats(&c->common);
	return TC_ACT_CONSUMED;

TC_ACT_CONSUMED means the action took ownership of the skb, so no caller
frees it - sch_handle_ingress(), sch_handle_egress() and
tcf_qevent_handle() all deliberately skip the free for that verdict. The
skb is therefore orphaned: one sk_buff plus its data buffer is leaked per
malformed packet, unbounded. Note the drop counter is already incremented
for these errors, so the statistics claim a drop that never happens.

Three different ownership states reach out_frag: today - the skb may be
queued by the defrag engine (-EINPROGRESS), already freed by
nf_ct_handle_fragments(), or still owned by us. Tell the caller which of
those it is, and free the packet ourselves in the last case, which
restores the TC_ACT_SHOT behaviour that predated the Fixes: commit.

Reproduced on v7.2-rc6 with a 54-byte frame carrying a 40-byte IPv6
header with nexthdr = 0 (hop-by-hop) and nothing after it, on a
clsact ingress chain with "action ct". kmemleak reports one leaked
232-byte skbuff_head_cache object plus its 704-byte data buffer per
packet; with this patch it reports none.

Fixes: 3f14b377d0 ("net/sched: act_ct: fix skb leak and crash on ooo frags")
Cc: stable@vger.kernel.org # v6.8+
Signed-off-by: Hyunjung Ko <hj351016@gmail.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://patch.msgid.link/20260806101235.809370-1-hj351016@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-10 16:37:07 -07:00
Oleksij Rempel
202fef9bbb net: phy: realtek: fix EEE advertisement write on the internal PHY MMD path
In rtlgen_write_mmd(), the MDIO_AN_EEE_ADV case swaps the arguments to
rtlgen_write_vend2(): it passes the MMD register number as the OCP address
and the OCP address constant as the value. The caller's value is discarded
and the write lands on the wrong register, so the EEE advertisement cannot
be configured on the affected PHYs.

Mirror rtlgen_read_mmd() and write the value to RTL_MDIO_AN_EEE_ADV.

Fixes: da681ed73f ("net: phy: realtek: improve mmd register access for internal PHY's")
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Nicolai Buchwitz <nb@tipi-net.de>
Link: https://patch.msgid.link/20260806134716.3511821-1-o.rempel@pengutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-10 16:05:05 -07:00
Jiayuan Chen
60837e4b84 tcp: fix icsk_ack.ato bitfield overflow
On cross-region connections we observed delayed ACKs suddenly turning
into immediate ACKs plus a TCP_MAX_QUICKACKS burst, as if the
connection had just received its first data segment.

Commit 95b9a87c6a ("tcp: record last received ipv6 flowlabel")
squeezed icsk_ack.ato into 8 bits, sized for TCP_DELACK_MAX. But both
writers still bound ato by icsk_rto, which can be well above 255
jiffies, so the bitfield assignment silently wraps mod 256: repeated
delack timer misses double ato up to icsk_rto, storing 320 as 64 and
256 as 0, and ato == 0 is the "first data packet" sentinel in
tcp_event_data_recv().

Clamp both writers to TCP_DELACK_MAX, which the static_assert already
guarantees to fit and tcp_send_delayed_ack() effectively caps ato at
anyway.

Fixes: 95b9a87c6a ("tcp: record last received ipv6 flowlabel")
Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Reviewed-by: Neal Cardwell <ncardwell@google.com>
Link: https://patch.msgid.link/20260807014437.36687-1-jiayuan.chen@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-10 16:02:30 -07:00
Hyunjung Ko
883b56ae58 net/sched: act_gact, act_police: range check the fallback control action
tcf_action_check_ctrlact() range checks the primary control action:

	if (!opcode)
		ret = action > TC_ACT_VALUE_MAX ? -EINVAL : 0;

TC_ACT_VALUE_MAX is TC_ACT_TRAP, so kernel-internal verdicts above it
cannot be set that way. But act_gact and act_police each carry a second,
independent control action supplied by user space that never reaches that
helper - TCA_GACT_PROB.paction and TCA_POLICE_RESULT. Both only reject
TC_ACT_GOTO_CHAIN, so any other value is stored verbatim and returned
verbatim from the action.

In particular user space can store TC_ACT_CONSUMED, which is
TC_ACT_VALUE_MAX + 1 and is deliberately not part of the UAPI value
range. That verdict tells every caller the action took ownership of the
skb, so nobody frees it: sch_handle_ingress(), sch_handle_egress() and
tcf_qevent_handle() all deliberately skip the free for it. The result is
one leaked sk_buff plus its data buffer per packet traversing the filter,
unbounded, for all traffic on the chain including kernel-generated
packets.

Both are trivially deterministic. act_gact clamps tcfg_pval to >= 1, so
with pval = 1 gact_determ() returns the fallback for every packet.
act_police has no mandatory rate, so rate = 0 leaves tcfp_mtu = ~0 and
tcf_police_mtu_check() always passes.

TC_ACT_CONSUMED was added by commit 720f22fed8 ("net: sched: refactor
reinsert action"), after both goto-chain guards were written:
commit 9469f375ab ("net/sched: act_gact: disallow 'goto chain' on
fallback control action") and
commit c08f5ed5d6 ("net/sched: act_police: disallow 'goto chain' on
fallback control action"). Neither guard was widened when the new
verdict appeared.

Factor the existing range test out of tcf_action_check_ctrlact() as
tcf_action_valid() and apply it to both fallbacks. The helper cannot call
tcf_action_check_ctrlact() directly because that also allocates a
goto_chain, which is exactly what these two sites must not do.

Reproduced on v7.2-rc6: kmemleak reports one leaked 232-byte
skbuff_head_cache object plus its 704-byte data buffer per packet. With
this patch both configurations are rejected with -EINVAL and kmemleak
reports none.

Fixes: 720f22fed8 ("net: sched: refactor reinsert action")
Cc: stable@vger.kernel.org # v5.3+
Signed-off-by: Hyunjung Ko <hj351016@gmail.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Tested-by: Victor Nogueira <victor@mojatatu.com>
Link: https://patch.msgid.link/20260806101252.809593-1-hj351016@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-10 16:00:19 -07:00
Jonas Köppeler
60db47f02b veth: fix queue index used to wake the peer txq in veth_poll
veth_poll() derives the index of the peer TX queue to wake from
rq->xdp_rxq.queue_index. That field is only initialized by
xdp_rxq_info_reg() in veth_enable_xdp_range(), which runs only when an
XDP program is attached. On the plain GRO/NAPI path
(veth_napi_enable_range()) xdp_rxq_info_reg() is never called, so
queue_index stays 0 for every queue, as priv->rq is zero-allocated.

So in a multi-queue setup with GRO enabled and no XDP program attached,
every NAPI instance looks at the peer's TX queue 0. If veth_xmit() stops
peer TX queue 1 because the ptr_ring is full (NETDEV_TX_BUSY), nothing
ever wakes it again: the poller draining queue 1 wakes queue 0 instead.
veth implements no ndo_tx_timeout, so the netdev watchdog does not kick
in either, and the queue stays stopped indefinitely.

Derive the index from the position of the rq within priv->rq instead,
which is correct regardless of whether XDP was ever enabled.

Scripts to reproduce the stall are available at
https://github.com/netoptimizer/veth-backpressure-performance-testing

Fixes: dc82a33297 ("veth: apply qdisc backpressure on full ptr_ring to reduce TX drops")
Signed-off-by: Jonas Köppeler <j.koeppeler@tu-berlin.de>
Tested-by: Jesper Dangaard Brouer <hawk@kernel.org>
Acked-by: Jesper Dangaard Brouer <hawk@kernel.org>
Link: https://patch.msgid.link/20260806-veth-fix-poll-queue-idx-v1-1-c5357fb7573d@tu-berlin.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-10 15:57:47 -07:00
Jakub Kicinski
92465f46f3 net: expect instance lock in netdev_queue_get_dma_dev()
netdev_queue_get_dma_dev() uses "compat" locking assert which wants
either the rtnl_lock or netdev instance lock. This is not right,
the callers are taking the instance lock unconditionally. All entry
points for queue config are purely instance locked.

In other words the callers use netdev_get_by_index_lock(), not
netdev_get_by_index_lock_ops_compat(). All the state we will
access is effectively instance lock protected (it's const for
devices which are not ops-locked).

Update the assert to avoid false positive warnings.

Cc: stable@vger.kernel.org
Fixes: b6c5f9454e ("io_uring/zcrx: call netdev_queue_get_dma_dev() under instance lock")
Reported-by: syzbot+a78926bdac2adb52dc0e@syzkaller.appspotmail.com
Reviewed-by: Simon Horman <horms@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://patch.msgid.link/20260806225627.3998672-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-10 15:54:42 -07:00
Eric Dumazet
cef51860be macvlan: inherit needed_headroom and needed_tailroom from lowerdev
macvlan devices inherit hard_header_len from lowerdev during macvlan_init(),
but leave needed_headroom and needed_tailroom set to 0.

When the underlying lowerdev requires extra headroom or tailroom for
headers/trailers (e.g. macsec, ipsec, wireguard, tunnels, or veth with rx
headroom), upper layers calculating packet headroom and tailroom fail to
reserve sufficient space.

This can result in reallocation overhead, skb headroom underflows, or KASAN
slab-use-after-free crashes when dev_hard_header() / macvlan_hard_header()
prepends header data or when lower devices append tailroom.

Fix this by:
1. Inheriting needed_headroom and needed_tailroom from lowerdev in macvlan_init().
2. Propagating needed_headroom and needed_tailroom updates to attached macvlans
   in macvlan_device_event() when receiving NETDEV_FEAT_CHANGE events.

Fixes: b863ceb7dd ("[NET]: Add macvlan driver")
Reported-by: Tangxin Xie <xietangxin@h-partners.com>
Closes: https://lore.kernel.org/netdev/CANn89i+1EW-sFNK8xoq98gMbPCeLS7e=+rs9gHfLg5Wj+4x0sw@mail.gmail.com/T/#m16adf0ff972cbfd8066c3a8e656e75eaeb12d021
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Hangbin Liu <liuhangbin@kylinos.cn>
Link: https://patch.msgid.link/20260806141938.287660-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-10 15:21:41 -07:00
Eric Dumazet
e16e960d55 ipvlan: inherit needed_headroom and needed_tailroom from phy_dev
ipvlan devices inherit hard_header_len from phy_dev during ipvlan_init(),
but leave needed_headroom and needed_tailroom set to 0.

When the underlying phy_dev (or stacked lower device) requires extra headroom
or tailroom for headers/trailers (e.g. macsec, ipsec, wireguard, tunnels, or
veth with rx headroom), upper layers calculating packet headroom and tailroom
fail to reserve sufficient space.

This can result in reallocation overhead, skb headroom underflows, or KASAN
slab-use-after-free crashes when dev_hard_header() / ipvlan_hard_header()
prepends header data or when lower devices append tailroom.

Fix this by:
1. Inheriting needed_headroom and needed_tailroom from phy_dev in ipvlan_init().
2. Propagating needed_headroom and needed_tailroom updates to attached ipvlans
   in ipvlan_device_event() when receiving NETDEV_FEAT_CHANGE events.

Fixes: 2ad7bf3638 ("ipvlan: Initial check-in of the IPVLAN driver.")
Reported-by: syzbot+1f9fd0f4b601cf88d6e6@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/6a720a21.40259c87.584f4.04bb.GAE@google.com/T/#u
Reported-by: Tangxin Xie <xietangxin@h-partners.com>
Closes: https://lore.kernel.org/netdev/CANn89i+1EW-sFNK8xoq98gMbPCeLS7e=+rs9gHfLg5Wj+4x0sw@mail.gmail.com/T/#mcc6307f115e500df23ea2980d5669fe95f20b6b4
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Hangbin Liu <liuhangbin@kylinos.cn>
Link: https://patch.msgid.link/20260806103857.115541-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-10 15:20:06 -07:00
Jakub Kicinski
33be82f43a Merge branch 'eth-bnxt-fix-irq-notifier-bugs'
Jakub Kicinski says:

====================
eth: bnxt: fix IRQ notifier bugs

I was trying to make bnxt preserve IRQ mappings across reconfiguration.
While hacking on that I noticed 2 bugs in the notifiers that should
probably be fixed before development work.

First one is simple - TPH recofig makes aARFs not work. There can only
be one notifier per IRQ and TPH "steals" the callback from the rmap
updates. Fix by patches 1 and 2.

Second one is a deadlock between the affinity notifier and reconfig.
This one is a bit more involved (patch 3 and 4).

Unfortunately, I can't really verify the problem or test the fix.
I managed to get my hands on a system with an AMD Venice CPU which
is supposed to support TPH, but the ACPI is missing some bits to
actually advertise it. pcie_tph_get_cpu_st() returns -EINVAL.
====================

Link: https://patch.msgid.link/20260803193135.2030368-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-10 15:15:08 -07:00
Jakub Kicinski
51e96fa31f eth: bnxt: avoid deadlock when canceling IRQ affinity notifier
Unregistering IRQ affinity notifiers waits for the callback synchronously.
bnxt takes the netdev instance lock in the notifier (to restart the queue)
and cancels the work under the same lock. This may obviously deadlock.

Move the restart to the async service task. The queue restart isn't
super time sensitive. Store the new TPH tag, schedule the task.
Safely canceling the service task is already ironed out.

In bnxt_request_irq() the order of registering notifier, affinity and
initial TPH programming has to be inverted. I think it was racy
previously since user may trigger an update as soon as notifier
is installed.

There's a small known gap - if pcie_tph_get_cpu_st() fails at init
and the target tag is 0 we may miss programming the entry.
This does not seem worth fixing, the code has skip-on-failure
all over the place, anyway.

Fixes: c214410c47 ("bnxt_en: Add TPH support in BNXT driver")
Tested-by: Vishvambar Panth S <vishvambar.panth-s@broadcom.com>
Link: https://patch.msgid.link/20260803193135.2030368-5-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-10 15:15:06 -07:00
Jakub Kicinski
0fd562c7b9 eth: bnxt: decrease indent in bnxt_request_irq()
bnxt_request_irq() has unnecessary level of indentation.
Use continue instead. No need to re-fetch NUMA node for
each IRQ, move to the function level.

No functional changes.

Reviewed-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260803193135.2030368-4-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-10 15:15:06 -07:00
Jakub Kicinski
4b5cb58a44 eth: bnxt: keep the aRFS rmap updated when TPH is enabled
The TPH support must have broken aRFS in bnxt. IRQ can only have one
notifier, so installing the TPH notifier is overriding the one implicitly
installed by irq_cpu_rmap_add().

Make sure we call cpu_rmap_update() from the TPH notifier.

We need to be careful with the ordering and not free the rmap
until we unregistered the notifier. Note that moving the rmap
freeing after the early return in bnxt_free_irq() is fine -
there's no path that could leave rmap with irq_tbl being NULL.

Fixes: c214410c47 ("bnxt_en: Add TPH support in BNXT driver")
Reviewed-by: Michael Chan <michael.chan@broadcom.com>
Link: https://patch.msgid.link/20260803193135.2030368-3-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-10 15:15:06 -07:00
Jakub Kicinski
c703f62c30 eth: bnxt: cancel IRQ notifier before freeing affinity mask
bnxt_irq_affinity_notify() copies into irq->cpu_mask.
Cancel the notifier before freeing irq->cpu_mask.

Fixes: c214410c47 ("bnxt_en: Add TPH support in BNXT driver")
Reviewed-by: Michael Chan <michael.chan@broadcom.com>
Link: https://patch.msgid.link/20260803193135.2030368-2-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-10 15:15:05 -07:00
Christoph Paasch
dd057113ac mailmap: add entries for Christoph Paasch
Map the email addresses used for previous kernel contributions to the
current OpenAI address. This prevents get_maintainer.pl from listing
historical addresses as patch recipients.

Suggested-by: Matthieu Baerts <matttbe@kernel.org>
Signed-off-by: Christoph Paasch <cpaasch@openai.com>
Acked-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20260806-b4-mailman-v1-1-b4d7bc0ffd1c@openai.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-07 18:20:12 -07:00
Jakub Kicinski
d47b06aa3e Merge branch 'fix-skb-length-accounting-after-xdp-frag-adjustment'
Sun Jian says:

====================
fix skb length accounting after XDP frag adjustment

This series fixes skb length accounting after an XDP program adjusts its
fragment area, in both the generic XDP path (net/core/dev.c) and the veth
native path (drivers/net/veth.c). When the fragment area is resized,
skb->len and skb->data_len can go out of sync, and in the reproduced UDP
receive path this leaked skb_shared_info contents (including a kernel
pointer) to userspace while truncating real payload.
====================

Link: https://patch.msgid.link/20260804054040.613675-1-sun.jian.kdev@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-07 17:01:10 -07:00
Sun Jian
cb6379feaa veth: fix skb length accounting after XDP frag adjustment
veth exposes non-linear skb fragments through an xdp_buff. If an XDP
program adjusts the fragment area, veth_xdp_rcv_skb() copies
xdp_frags_size back to skb->data_len but leaves skb->len containing the
old fragment contribution.

After a fragment shrink, this makes skb_headlen() larger than the actual
linear area. In the reproduced UDP receive path, __skb_datagram_iter()
copied 1024 bytes past the actual linear tail to userspace, starting at
struct skb_shared_info. The copied bytes included the affected skb's
nr_frags, xdp_frags_size, and a kernel pointer from
skb_shinfo(skb)->frags[0]. Real packet data was displaced by the same
amount and truncated at the end.

Subtract the old data_len before replacing it and add the new data_len
afterwards, keeping skb->len and skb->data_len synchronized.

Additionally, bpf_xdp_pull_data() can advance data_end while leaving
frags present. The skb is then still non-linear, so the old
__skb_put(skb, off) triggers SKB_LINEAR_ASSERT().

Use skb_set_tail_pointer() and update skb->len explicitly instead,
following bpf_prog_run_generic_xdp(). Unlike __skb_put(),
skb_set_tail_pointer() does not require a linear skb.

A 60000-byte UDP datagram on a veth pair with MTU 64000 was shortened by
1024 bytes from its fragment area. Before the fix, all 10 runs produced
corrupted payloads. After the fix, all 10 runs matched the expected
payload exactly. A forced-tailroom reproducer also exercises
bpf_xdp_pull_data() with frags still present; the old code triggers
SKB_LINEAR_ASSERT(), while this fix passes 10/10 runs.

Fixes: 718a18a0c8 ("veth: Rework veth_xdp_rcv_skb in order to accept non-linear skb")
Cc: stable@vger.kernel.org
Reported-by: Mohsin Bashir <mohsin.bashr@gmail.com>
Link: https://lore.kernel.org/bpf/80687d9c-9c27-494c-b3f2-efd0230b1895@gmail.com/
Suggested-by: Lorenzo Bianconi <lorenzo@kernel.org>
Acked-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Sun Jian <sun.jian.kdev@gmail.com>
Link: https://patch.msgid.link/20260804054040.613675-3-sun.jian.kdev@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-07 17:01:05 -07:00
Sun Jian
33f2b2eb33 net: fix skb length accounting after generic XDP frag adjustment
Generic XDP exposes non-linear skb fragments through an xdp_buff. If an
XDP program adjusts the fragment area, bpf_prog_run_generic_xdp() copies
xdp_frags_size back to skb->data_len but leaves skb->len containing the
old fragment contribution.

After a fragment shrink, this makes skb_headlen() larger than the actual
linear area. In the reproduced UDP receive path, __skb_datagram_iter()
copied 1024 bytes past the actual linear tail to userspace, starting at
struct skb_shared_info. The copied bytes included the affected skb's
nr_frags, xdp_frags_size and a kernel pointer from
skb_shinfo(skb)->frags[0]. Real packet data was displaced by the same
amount and truncated at the end.

Subtract the old data_len before replacing it and add the new data_len
afterwards, keeping skb->len and skb->data_len synchronized.

A 60000-byte UDP datagram on a veth pair with MTU 64000 was shortened by
1024 bytes from its fragment area. Before the fix, all 10 runs produced
corrupted payloads. After the fix, all 10 runs matched the expected
payload exactly.

Fixes: e6d5dbdd20 ("xdp: add multi-buff support for xdp running in generic mode")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/bpf/al9T9Eto%2FhRIzP5W@boxer/
Reviewed-by: Mohsin Bashir <hmohsin@meta.com>
Acked-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Sun Jian <sun.jian.kdev@gmail.com>
Link: https://patch.msgid.link/20260804054040.613675-2-sun.jian.kdev@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-07 17:01:05 -07:00
Jérémy Jean
3dbb44d88b sctp: validate cookie AUTH state before use
When cookie authentication is disabled, COOKIE_ECHO restores fixed-size
AUTH fields directly from peer-controlled cookie bytes.  A forged RANDOM
length, HMAC list, or CHUNKS list can then reach association consumers
with lengths or identifiers that were never validated against the local
backing arrays.

A forged RANDOM length can cause out-of-bounds reads during key-vector
construction.  A forged HMAC identifier also caused a 32-byte write past
a zero-length AUTH chunk, providing a primitive for a local privilege
escalation chain.

Validate the cookie's RANDOM, HMACS, and CHUNKS parameters at the cookie
trust boundary before copying them into the association.  Reject invalid
types, malformed lengths, unsupported HMAC identifiers, HMAC lists
without SHA1, and forbidden chunk ids.

Fixes: bbd0d59809 ("[SCTP]: Implement the receive and verification of AUTH chunk")
Fixes: 1f485649f5 ("[SCTP]: Implement SCTP-AUTH internals")
Signed-off-by: Jérémy Jean <Jeremy.Jean@oss.cyber.gouv.fr>
Acked-by: Xin Long <lucien.xin@gmail.com>
Link: https://patch.msgid.link/20260804200042.2412009-1-Jeremy.Jean@oss.cyber.gouv.fr
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-07 15:02:32 -07:00
Kuniyuki Iwashima
594d905195 af_unix: Unlink scc_entry in unix_del_edge().
Kyle Zeng reported that GC could free a dead SCC partially.

The scenario is as follows:

   1) Create two SCCs:

       X -.   A <-> B
       ^--'

   2) Run the following concurrently:

      2-1) send() sk-B to sk-B from sk-X
      2-2) close() both A and B

At 2-1), there is a small window where unix_add_edges()
publishes a new edge (B <-> B) to GC but its skb is not queued
by skb_queue_tail().

If 2-2) completes before skb_queue_tail() and GC is triggered,
it judges A <-> B as dead, but B is not freed because GC cannot
collect the not-yet-queued skb holding the B <-> B edge.

       X -.   A <-> B -. This edge is visible
       ^--'         ^..'  but skb is not

This itself is not a problem since the next GC run will judge
B as dead as well and free it finally.

       X -.   A <.> B -.
       ^--'         ^--'

However, X's SCC forces the next GC to call unix_walk_scc_fast(),
and it iterates over A through B's scc_entry.

Let's unlink scc_entry before freeing the vertex in unix_del_edge().

Fixes: 4090fa373f ("af_unix: Replace garbage collection algorithm.")
Reported-by: Kyle Zeng <kylebot@openai.com>
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Kyle Zeng <kylebot@openai.com>
Fixes: 4090fa373f ("af_unix: Replace garbage collection algorithm.").
Link: https://patch.msgid.link/20260804002155.2233594-1-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-06 11:52:48 -07:00
Linus Torvalds
315f4bd234 Merge tag 'net-7.2-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Jakub Kicinski:
 "Including fixes from netfilter.

  Looks like our attempt to keep the PRs smaller have only prevented
  this one from getting even bigger. In the last 9 days there were
  405 postings explicitly tagged with [PATCH net], vs 687 with [PATCH
  net-next]. 37% of posted patches being fixes is pretty crazy, and
  that's likely undercounting because LLM "researchers" more often post
  fixes without knowing to tag the patches for specific trees. I don't
  have historic data.

  In any case, we keep adjusting the criteria. The next PR will be
  smaller.

  Current release - regressions:

   - net: defer netdev KOBJ_ADD uevent until the device is published,
     previously rtnl_lock would serialize the accesses vs publishing

   - net: explicitly cancel work to avoid races with ref tracker exit

   - qrtr: ns: raise lookup limit to 128

   - eth: hns3: fix speed configuration residue after driver reload

  Previous releases - regressions:

   - tcp: do not change rcv_ssthresh in tcp_measure_rcv_mss(), regressed
     flows with MSS and scaling_ratio variability

   - Revert "net: thunderbolt: Enable end-to-end flow control also in
     transmit", broke some platforms (no packets coming thru)

   - eth: stmmac: resume PHY before hardware setup when opening the
     interface

  Previous releases - always broken:

   - another pile of fixes for less common protocols (SCTP, TLS, SMC
     etc.)

   - close a couple of AF_PACKET bugs and ways it can build skbs
     problematic for the rest of the stack

   - bridge: mrp: fix uninitialised bytes on the wire

   - net: devmem: prevent net-iov / page mixing, avoid crashes

   - eth: atlantic: free RX pages of consumed but not refilled buffers"

* tag 'net-7.2-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (116 commits)
  igc: fix netdev not re-attached after resume if interface is down
  tls: don't abort the connection on signal-interrupted sends
  net: avoid theoretical races with ref drain
  net: Defer netdev KOBJ_ADD uevent until the device is published
  MAINTAINERS: dpll: zl3073x: replace Prathosh Satish with Min Li
  sctp: clear control chunk transport if it is being removed
  net/atm: fix slab-out-of-bounds read in vcc_setsockopt()
  s390/ism: Fix UAF of sba and ieq during ism_dev_exit()
  packet: use consistent hard_header_len in TX_RING send path
  packet: use consistent hard_header_len in non-ring send paths
  net: remove CAP_SYS_RAWIO zero-padding in dev_validate_header
  bnge: Fix resource leak in bnge_init_nic() error path
  ptp: ocp: Fix board ID over-read
  tls: rx: restore msg_iter before TLS 1.3 optimistic retry
  selftests: tls: add a test for splicing onto a full plaintext record
  tls: don't leave a full plaintext sk_msg ring unpushed
  xdp: reject clones that overrun skb_shared_info tailroom
  mptcp: reclaim forward-allocated memory on RX path errors
  mptcp: fastopen: only mark MPTFO subflows with SYN data
  mptcp: pm: fix memory leak from alloc-during-teardown race
  ...
2026-08-06 11:39:20 -07:00
Philipp David
b0ce5fd9fa igc: fix netdev not re-attached after resume if interface is down
__igc_resume() calls netif_device_attach() only inside the
netif_running() branch, so an interface that was down during suspend
is never re-attached on resume. It then stays in the not-present state
that __igc_shutdown() set via netif_device_detach(): ethtool reports
ENODEV and every attempt to bring the interface up fails the
netif_device_present() check in __dev_open() with -ENODEV, silently,
since __igc_resume() returns 0. Only reloading the driver recovers the
device.

This is easy to hit in practice because NetworkManager brings managed
interfaces down before sleep unless Wake-on-LAN is configured, making
the adapter unusable after every suspend/resume cycle with WoL
disabled.

Re-attach the netdev on every successful resume, as igb and e1000e do.

Fixes: 6f31d6b643 ("igc: Refactor runtime power management flow")
Cc: stable@vger.kernel.org
Signed-off-by: Philipp David <pd-lkml@3b.pm>
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Reviewed-by: Dima Ruinskiy <dima.ruinskiy@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Link: https://patch.msgid.link/20260804222205.1580328-11-anthony.l.nguyen@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-06 10:21:28 -07:00
Maximilian Immanuel Brandtner
af0e5cdd03 tls: don't abort the connection on signal-interrupted sends
When a signal interrupts a blocking send, tls_tx_records() treats the
resulting -ERESTARTSYS as a transmission failure and marks the socket
errored via tls_err_abort() with the raw error code. Later syscalls
return the kernel-internal errno 512 (ERESTARTSYS) to userspace, as the
signal it stems from is no longer pending during syscall exit and thus
never translated.

An interrupted send is not a connection error: the partially sent record
stays queued and is resent later. Interrupt error codes are therefore
excluded from the abort in the same way as -EAGAIN.

Fixes: b341ca51d2 ("tls: Fix tls_sw_sendmsg error handling")
Signed-off-by: Maximilian Immanuel Brandtner <maxbr@linux.ibm.com>
Link: https://patch.msgid.link/20260805063109.1772314-1-maxbr@linux.ibm.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-06 09:38:20 -07:00
Jakub Kicinski
d31c14e56a net: avoid theoretical races with ref drain
Technically, it's illegal to take a ref on a netdev just because
we have a pointer on which we already hold a ref, with no other
protection. This is because our simple per-cpu refcount
implementation cannot atomically read the count.

Let's make sure we cancel outstanding work and never queue more
work for a device we know is dead. This way taking a ref on
a dev we know is on the netdev_work_list is always going to be safe.

Jiangshan Yi reports that the issues is caught by ref tracker infra
leading to a warning:
  WARNING: lib/ref_tracker.c:322 at ref_tracker_free
  WARNING: lib/ref_tracker.c:246 at ref_tracker_dir_exit

Reported-by: Jiangshan Yi <yijiangshan@kylinos.cn>
Link: https://lore.kernel.org/20260731035135.3917308-2-yijiangshan@kylinos.cn
Fixes: 12c765be84 ("net: turn the rx_mode work into a generic netdev_work facility")
Link: https://patch.msgid.link/20260806022821.2079945-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-06 09:37:03 -07:00
Dragos Tatulea
8e63c9e617 net: Defer netdev KOBJ_ADD uevent until the device is published
netdev_register_kobject() calls device_add(), which emits KOBJ_ADD and
wakes udev, but register_netdevice() only makes the device findable by
name later, in list_netdevice().  A udev worker that reacts to the uevent
can therefore run against a device that no lookup can find yet.

This used to be harmless because the ethtool ioctl took the rtnl_lock
when looking the device up, and register_netdevice() runs under rtnl, so
the worker simply blocked until registration finished. The commit in the
fixes tag moved the lookup out from under rtnl for ops-locked drivers.
Now there is a short window in register_netdevice() between
netdev_register_kobject() until list_netdevice() when the device is not
findable by name.

This was reproduced with the mlx5 driver on a kernel with KASAN enabled
during devlink reload: systemd-udevd's net_driver builtin gets -ENODEV
from ETHTOOL_GDRVINFO, which was preventing interface renaming.

Suppress the uevent in netdev_register_kobject() and emit it from
register_netdevice() next to rtmsg_ifinfo(). This is the last point in
register_netdevice() where no error can happen, so only fully registered
devices are announced: the registration error paths never reach it, and
the device_del() that unwinds them stays silent as well, leaving
userspace with neither an add nor a remove.

Fixes: f994752b11 ("net: ethtool: optionally skip rtnl_lock on IOCTL path")
Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com>
Reviewed-by: Shahar Shitrit <shshitrit@nvidia.com>
Link: https://patch.msgid.link/20260806080758.2039586-2-dtatulea@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-06 09:36:18 -07:00
Ivan Vecera
03a736fde4 MAINTAINERS: dpll: zl3073x: replace Prathosh Satish with Min Li
Replace Prathosh Satish by Min Li as the Microchip co-maintainer
of the ZL3073X DPLL driver.

Signed-off-by: Ivan Vecera <ivecera@redhat.com>
Link: https://patch.msgid.link/20260805155425.38808-1-ivecera@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-06 09:30:07 -07:00
Xin Long
c9158ceaf2 sctp: clear control chunk transport if it is being removed
sctp_make_heartbeat_ack() caches the destination transport in
chunk->transport without taking a reference. When src_out_of_asoc_ok is
enabled, the HEARTBEAT ACK may remain queued on control_chunk_list instead
of being transmitted immediately.

If the peer transport is removed while the chunk is still queued,
sctp_assoc_rm_peer() drops the transport and schedules it for RCU freeing,
but only clears cached transport pointers in out_chunk_list.  The queued
control chunk therefore retains a dangling transport pointer.

Once an ASCONF_ACK clears the suppression and the queued control chunk is
transmitted, SCTP dereferences the stale transport pointer, leading to a
use-after-free.

Fix this by also clearing chunk->transport for queued control chunks in
control_chunk_list when removing the transport.

Fixes: 8a07eb0a50 ("sctp: Add ASCONF operation on the single-homed host")
Reported-by: Daniele Linguaglossa <danielelinguaglossa@gmail.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Link: https://patch.msgid.link/7e1168cb722132152a29d47e5eafaeac4a3bf6f3.1785943120.git.lucien.xin@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-06 09:29:47 -07:00
Eric Dumazet
d0c80dbb97 net/atm: fix slab-out-of-bounds read in vcc_setsockopt()
vcc_setsockopt() contained an ineffective optlen check:
  if (__SO_LEVEL_MATCH(optname, level) && optlen != __SO_SIZE(optname))
      return -EINVAL;

If __SO_LEVEL_MATCH(optname, level) evaluated to false (e.g. if the caller
passed a mismatched level), the length check optlen != __SO_SIZE(optname)
was short-circuited and bypassed. Execution then fell through to switch(optname),
calling copy_from_sockptr() assuming optval contained sufficient space.

Furthermore, even if level matched, a cgroup BPF setsockopt filter could shrink
optlen after entry. Because copy_from_sockptr() on kernel pointers uses memcpy(),
this leads to a KASAN slab-out-of-bounds read when optlen is smaller than the
expected structure size.

Fix this by using copy_safe_from_sockptr(), which unconditionally validates
that optlen is at least the expected size before copying. Also change the local
'value' variable type from 'unsigned long' to 'int' so that SO_SETCLP matches
its sizeof(int) ABI encoding on 64-bit systems.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reported-by: syzbot+53ecc09fb81df10ef4de@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=53ecc09fb81df10ef4de
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260805131508.3227331-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-06 09:29:14 -07:00
Alexandra Winter
b1896543ce s390/ism: Fix UAF of sba and ieq during ism_dev_exit()
A ism interrupt handler can be active in parallel with ism_dev_exit(),
accessing freed data structures.

No new interrupts will be generated after unregister_ieq(). Drain ongoing
interrupt handlers by free_irq(), before freeing ism data structures.

Fixes: 684b89bc39 ("s390/ism: add device driver for internal shared memory")
Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
Link: https://patch.msgid.link/20260805131043.954639-1-wintera@linux.ibm.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-06 09:28:33 -07:00
Jakub Kicinski
4be5b041e6 Merge branch 'net-fix-hard_header_len-races-in-packet-send-paths'
Qihang Tang says:

====================
net: fix hard_header_len races in packet send paths

The packet socket TX paths read dev->hard_header_len independently for
skb allocation and header construction. Concurrent netdevice
reconfiguration (e.g. bonding device type changes) can change this value
in between, leading to mismatched headroom and copy length, and in the
SOCK_RAW case to out-of-bounds writes.

Patch 1 removes the CAP_SYS_RAWIO zero-padding branch in
dev_validate_header(). That branch sizes a memset against the live
dev->hard_header_len while operating on an skb whose headroom was
allocated from an earlier hard_header_len read, so a concurrent increase
can write past the reserved buffer. Removing it first keeps the later
snapshot fixes bisect-safe: they do not replace an earlier skb_under_panic
with a silent overwrite.

Patches 2 and 3 snapshot hard_header_len once per send and use it
consistently for allocation and construction, in the non-ring and TX_RING
paths respectively. The separate SOCK_DGRAM consistency problem between
hard_header_len and header_ops->create remains out of scope, as noted in
the commit messages.
====================

Link: https://patch.msgid.link/20260805125729.19220-1-q.h.hack.winter@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-06 09:27:25 -07:00
Qihang Tang
21b5953e74 packet: use consistent hard_header_len in TX_RING send path
tpacket_snd() reads dev->hard_header_len independently for skb
allocation and header construction in tpacket_fill_skb(). Concurrent
netdevice reconfiguration can therefore make the reserved headroom
smaller than the amount later pushed, or make copylen - hard_header_len
negative.

Snapshot hard_header_len once before processing ring frames and use it
for the frame limit, headroom allocation, copy length, and skb
construction. Pass the snapshot to tpacket_fill_skb().

The separate SOCK_DGRAM consistency problem between hard_header_len and
header_ops->create is not addressed here.

Fixes: 69e3c75f4d ("net: TX_RING and packet mmap")
Cc: stable@vger.kernel.org
Signed-off-by: Qihang Tang <q.h.hack.winter@gmail.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260805125729.19220-4-q.h.hack.winter@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-06 09:27:21 -07:00
Qihang Tang
03390aa32e packet: use consistent hard_header_len in non-ring send paths
packet_snd() reads dev->hard_header_len multiple times while allocating
and constructing an skb. Device reconfiguration can change this value
concurrently, for example through bonding device type changes.

For SOCK_RAW, packet_snd() can save a larger value in reserve and later
allocate headroom using a smaller value. Moving skb->data back by reserve
then places it before skb->head, and the following copy from userspace can
attempt an out-of-bounds write.

packet_sendmsg_spkt() has the same issue because it calculates its
reservation and header offset from separate reads before dropping the RCU
read lock to allocate the skb.

Add LL_RESERVED_SPACE_EX() for callers that already saved a header length.
Read hard_header_len once in packet_snd() and use it for allocation and
construction. In packet_sendmsg_spkt(), preserve the allocation-time value
through the device lookup retry.

The separate SOCK_DGRAM consistency problem between hard_header_len and
header_ops->create is not addressed here.

Fixes: b84bbaf7a6 ("packet: in packet_snd start writing at link layer allocation")
Cc: stable@vger.kernel.org
Signed-off-by: Qihang Tang <q.h.hack.winter@gmail.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260805125729.19220-3-q.h.hack.winter@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-06 09:27:21 -07:00
Qihang Tang
3b9a324e64 net: remove CAP_SYS_RAWIO zero-padding in dev_validate_header
dev_validate_header() reads dev->hard_header_len directly when
zero-padding short link layer headers for CAP_SYS_RAWIO holders:

    if (capable(CAP_SYS_RAWIO)) {
        memset(ll_header + len, 0, dev->hard_header_len - len);
        return true;
    }

Packet send paths call dev_validate_header() on skbs whose headroom was
allocated from an earlier hard_header_len read. If the device is
reconfigured so that dev->hard_header_len increases before validation,
the memset writes past the reserved buffer, an out-of-bounds write.

This out-of-bounds write is masked in some SOCK_RAW paths today because
the same concurrent increase can first make skb_push() exceed the
reserved headroom and trigger skb_under_panic(). Remove the zero-padding
branch before making those hard_header_len reads consistent, so the
snapshot fixes do not turn a loud panic into a silent overwrite.

This path is only reached for variable length L2 protocols, where
len < hard_header_len but len >= min_header_len. No remaining in-tree
variable length L2 protocol implements header_ops->validate, and the
CAP_SYS_RAWIO bypass that zero-pads and accepts short headers has no
real value beyond allowing testing of intentionally malformed input.

Drop the CAP_SYS_RAWIO branch. The remaining reads of
dev->hard_header_len in dev_validate_header() are comparisons only and
have no memory safety impact.

Suggested-by: Willem de Bruijn <willemb@google.com>
Fixes: 2793a23aac ("net: validate variable length ll headers")
Cc: stable@vger.kernel.org
Signed-off-by: Qihang Tang <q.h.hack.winter@gmail.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260805125729.19220-2-q.h.hack.winter@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-06 09:27:21 -07:00
Bhargava Marreddy
bfec39ff14 bnge: Fix resource leak in bnge_init_nic() error path
If bnge_init_chip() fails, bnge_init_nic() jumps to err_free_ring_grps
and returns immediately, skipping cleanup for RX ring pair buffers.

Remove the early return so execution falls through to
err_free_rx_ring_pair_bufs to properly free resources on error.

Fixes: 23df6aebf8 ("bng_en: Allocate stat contexts")
Signed-off-by: Bhargava Marreddy <bhargava.marreddy@broadcom.com>
Reviewed-by: Dharmender Garg <dharmender.garg@broadcom.com>
Reviewed-by: Rajashekar Hudumula <rajashekar.hudumula@broadcom.com>
Link: https://patch.msgid.link/20260805094022.15487-1-bhargava.marreddy@broadcom.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-06 09:26:22 -07:00
Ahmad Byagowi
6b69f2ef10 ptp: ocp: Fix board ID over-read
The EEPROM board ID is a fixed 13-byte field and is not guaranteed to
contain a NUL terminator. Passing it directly to
devlink_info_version_fixed_put() treats it as a C string and may read
beyond the field.

Format at most OCP_BOARD_ID_LEN bytes into the existing local buffer
before reporting the ID. Use a precision limit because the snprintf()
output size alone does not bound the source string scan.

Fixes: 0cfcdd1ebc ("ptp: ocp: add nvmem interface for accessing eeprom")
Cc: stable@vger.kernel.org
Signed-off-by: Ahmad Byagowi <ahmadexp@gmail.com>
Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Link: https://patch.msgid.link/20260804210751.48248-1-ahmadexp@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-06 09:15:40 -07:00
Jérémy Jean
1c8629651c tls: rx: restore msg_iter before TLS 1.3 optimistic retry
tls_decrypt_sg() advances msg->msg_iter when it maps user pages for
the optimistic TLS 1.3 zero-copy path. If the decrypted record turns
out not to be unpadded application data, tls_decrypt_sw() retries into
a kernel skb, but leaves the iterator advanced.

The subsequent copy from the skb then writes decrypted bytes again at
a later point in the caller iovecs while recvmsg() reports only the
post-retry length. A TLS peer can trigger this after the receiver
enables TLS_RX_EXPECT_NO_PAD.

Revert the iterator by the number of bytes consumed by the optimistic
mapping before retrying without zero-copy.

Add a selftest which sends a TLS 1.3 control record with
TLS_RX_EXPECT_NO_PAD enabled and verifies that recvmsg() does not
overwrite later iovecs beyond the returned length.

Fixes: ce61327ce9 ("tls: rx: support optimistic decrypt to user buffer with TLS 1.3")
Cc: stable@vger.kernel.org
Signed-off-by: Jérémy Jean <Jeremy.Jean@oss.cyber.gouv.fr>
Link: https://patch.msgid.link/20260804125528.2139928-1-Jeremy.Jean@oss.cyber.gouv.fr
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-06 09:08:58 -07:00
Jakub Kicinski
1f042e426b Merge branch 'tls-fix-plaintext-sk_msg-ring-over-fill'
chanyoung says:

====================
tls: fix plaintext sk_msg ring over-fill

An unprivileged user can oops the kernel by splicing into a kTLS socket
whose open record already has a full plaintext sk_msg ring.  Reproduced on
net (53658c6f36) with a stock config, no KASAN.

Patch 2 oopses an unpatched kernel and passes with patch 1 applied.
====================

Link: https://patch.msgid.link/20260804052837.49015-1-ppoo1220@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-06 09:01:56 -07:00
chanyoung
3834e079d6 selftests: tls: add a test for splicing onto a full plaintext record
Splicing onto a plaintext sk_msg ring that is already full used to wrap the
ring and make the kernel oops in the scatterwalk once the record was
pushed.

Only the copy path leaves the ring full without pushing it, so splice until
the ring is one fragment short, add the last fragment with a one-byte
MSG_MORE send, and splice once more before pushing the record.

CONFIG_MAX_SKB_FRAGS is 17..45, so that last fragment follows between 16
and 44 splices; sweep that range to trigger the bug on any build.

Signed-off-by: chanyoung <ppoo1220@gmail.com>
Link: https://patch.msgid.link/20260804052837.49015-3-ppoo1220@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-06 09:01:54 -07:00
chanyoung
7bca91d633 tls: don't leave a full plaintext sk_msg ring unpushed
When the copy path in tls_sw_sendmsg_locked() adds the fragment that fills
the plaintext sk_msg ring, it does not set full_record, so the record is
left full and unpushed.  A later splice() then adds to an already full
ring: sk_msg_page_add() has no fullness check of its own, so sg.end wraps
onto sg.start and the ring appears empty.  Fragments added after that
overwrite live entries, and sg.size no longer matches what is reachable
between sg.start and sg.end, so pushing the record runs the scatterwalk off
the end of the scatterlist.

An unprivileged user can trigger this on a loopback TCP socket with the
"tls" ULP attached:

  BUG: kernel NULL pointer dereference, address: 0000000000000008
  RIP: 0010:memcpy_from_scatterwalk+0x32/0xc0
  Call Trace:
   skcipher_walk_next+0x1d1/0x2c0
   gcm_encrypt_aesni_avx+0x1e9/0x220
   bpf_exec_tx_verdict+0x3bb/0x860
   tls_sw_sendmsg+0xa1a/0xca0
   __sys_sendto+0x1da/0x1f0

Set full_record in the copy path when the ring becomes full, and push a
record that is already full on entry to the sendmsg loop.

Suggested-by: Sabrina Dubroca <sd@queasysnail.net>
Fixes: fe1e81d4f7 ("tls/sw: Support MSG_SPLICE_PAGES")
Cc: stable@vger.kernel.org
Signed-off-by: chanyoung <ppoo1220@gmail.com>
Link: https://patch.msgid.link/20260804052837.49015-2-ppoo1220@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-06 09:01:54 -07:00
Zhiling Zou
e48e8edbef xdp: reject clones that overrun skb_shared_info tailroom
xdpf_clone() clones broadcast copies into a single page and sets
frame_sz to PAGE_SIZE. __xdp_build_skb_from_frame() later treats that
page like a normal XDP frame and expects the usual skb_shared_info
tailroom at the end of the buffer.

The current check only rejects frames whose linear xdp_frame header,
headroom, and packet data exceed PAGE_SIZE. A source frame backed by a
larger allocation can still satisfy that check while extending into the
clone's required shared-info area. When such a clone is converted back
into an skb, build_skb_around() places skb_shared_info over live packet
bytes and later writes can corrupt XDP return metadata.

Reject clones unless their linear area fits inside
SKB_WITH_OVERHEAD(PAGE_SIZE), matching the tailroom requirement already
enforced by the XDP-to-skb conversion path.

Fixes: e624d4ed4a ("xdp: Extend xdp_redirect_map with broadcast support")
Cc: stable@vger.kernel.org
Reported-by: Vega <vega@nebusec.ai>
Signed-off-by: Zhiling Zou <zhilinz@nebusec.ai>
Link: https://patch.msgid.link/6b2afef5d1738763c6965e8e466eb16e43e4f956.1785757386.git.zhilinz@nebusec.ai
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-06 08:49:19 -07:00
Jakub Kicinski
c53900b3f1 Merge branch 'mptcp-misc-fixes-for-v7-2-rc6'
Matthieu Baerts says:

====================
mptcp: misc fixes for v7.2-rc6

Here are various unrelated fixes:

- Patches 1-3: harden incoming MPTCP suboptions parsing by rejecting
  non-combinable ones. Patch 3 removes unreachable code after patch 2
  added here for consistency, and to reduce comments from AI reviews.
  Fixes for v5.6.

- Patch 4: fix a data race in the ADD_ADDR timer callback. A fix for
  v5.13.

- Patch 5: correctly catch data corruption during the MPTCP join
  selftest by marking tests as failed, instead of only printing a
  warning. A fix for v5.18.

- Patch 6: fix a leak with the userspace ADD_ADDR list in case of race
  condition during teardown. A fix for v5.19.

- Patch 7: deal with MPTFO with a valid token, but no data in the SYN. A
  fix for v6.2.

- Patch 8: reclaim forward-allocated memory in case of error on the
  receive side. A fix for v6.19.
====================

Link: https://patch.msgid.link/20260803-net-mptcp-misc-fixes-7-2-rc6-v2-0-b8f496d71664@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-06 08:46:26 -07:00
Paolo Abeni
41b49a8b91 mptcp: reclaim forward-allocated memory on RX path errors
After commit 9db5b3cec4 ("mptcp: borrow forward memory from subflow"),
errors in the receive path prior to queueing skbs into the receive
queue do not trigger forward-allocated memory reclaiming.

Prevent forward memory from growing unboundedly in pathological drop
scenarios by explicitly reclaiming memory when skbs are dropped.

Fixes: 9db5b3cec4 ("mptcp: borrow forward memory from subflow")
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/20260803-net-mptcp-misc-fixes-7-2-rc6-v2-8-b8f496d71664@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-06 08:46:24 -07:00
Wyatt Feng
e00b63056f mptcp: fastopen: only mark MPTFO subflows with SYN data
Passive TCP Fast Open accepts a valid-cookie SYN even when it carries
no data. In that case the child socket's receive queue is intentionally
left empty.

mptcp_fastopen_subflow_synack_set_params() set is_mptfo before checking
for queued SYN data. That made data-less TFO SYNs hit a WARN and, if
the warning was non-fatal, left stale MPTFO state behind. The stale
flag could later trigger a state-confusion bug in
check_fully_established().

Only mark the subflow as MPTFO after confirming that an SKB was queued.
Return quietly when the receive queue is empty.

Note that mptcp_subflow_context's is_mptfo field is now not just about
subflows where the TFO was present, but about MPTFO subflow that
consumed SYN data. Only having a valid cookie but not carrying data is
not really "doing TFO".

Fixes: 36b122baf6 ("mptcp: add subflow_v(4,6)_send_synack()")
Cc: stable@vger.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: Zhengchuan Liang <zcliangcn@gmail.com>
Reported-by: Xin Liu <bird@lzu.edu.cn>
Signed-off-by: Wyatt Feng <bronzed_45_vested@icloud.com>
Signed-off-by: Ren Wei <n05ec@lzu.edu.cn>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20260803-net-mptcp-misc-fixes-7-2-rc6-v2-7-b8f496d71664@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-06 08:46:23 -07:00
Shardul Bankar
efc33b5102 mptcp: pm: fix memory leak from alloc-during-teardown race
mptcp_pm_destroy() empties msk->pm.anno_list and
msk->pm.userspace_pm_local_addr_list under msk->pm.lock during socket
teardown, dropping the lock between the two.

A concurrent userspace PM genl ANNOUNCE on the same msk holds a sock
reference via mptcp_token_get_sock() and, in
mptcp_pm_nl_announce_doit(), calls
mptcp_userspace_pm_append_new_local_addr() and
mptcp_pm_announced_alloc(). Both take msk->pm.lock briefly to add to
their respective lists. Because the genl handler holds a sock reference,
mptcp_pm_destroy() may run on the same msk via mptcp_disconnect(), which
invokes mptcp_destroy_common() without dropping the sock refcount,
before the handler completes.

If the lock acquisitions interleave such that mptcp_pm_destroy() empties
a list first, the later alloc adds its entry to a list head that nothing
else iterates for this msk, and the entry leaks. kmemleak reports both
mptcp_pm_add_addr objects (from mptcp_pm_announced_alloc()) and
mptcp_pm_addr_entry objects (from
mptcp_userspace_pm_append_new_local_addr()) under sustained concurrent
ANNOUNCE + close load against the userspace PM.

Add an MPTCP_PM_DESTROYING bit in msk->pm.status, set by
mptcp_pm_destroy() under pm.lock before the lists are emptied and
checked under pm.lock by the alloc paths. Either the alloc takes pm.lock
first, in which case its entry is on the list when mptcp_pm_destroy()
frees it; or mptcp_pm_destroy() takes pm.lock first, in which case the
later alloc observes the bit and refuses.

Found by an MPTCP protocol-flow harness extending BRF (arXiv:2305.08782).

Fixes: 9ab4807c84 ("mptcp: netlink: Add MPTCP_PM_CMD_ANNOUNCE")
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/20260803-net-mptcp-misc-fixes-7-2-rc6-v2-6-b8f496d71664@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-06 08:46:23 -07:00
Gang Yan
ca318e7bbb selftests: mptcp: join: mark tests with data corruption as failed
check_transfer() compares the input and output files byte-by-byte using
`cmp -l "$in" "$out" | while read ...`. Because the while-loop body runs
in a subshell (the script sets neither lastpipe nor pipefail), the
fail_test call inside it -- which sets the global ret/last_test_failed --
and the `return 1` both act on the subshell, not on check_transfer().

check_transfer() thus always falls through to `return 0`, and any data
corruption affecting only the payload (leaving the subflow/PM counters
untouched) is silently reported as PASS.

Fixes: 8117dac3e7 ("selftests: mptcp: add invert check in check_transfer")
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/20260803-net-mptcp-misc-fixes-7-2-rc6-v2-5-b8f496d71664@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-06 08:46:23 -07:00
Qing Luo
a7aad5b69d mptcp: pm: fix data race in add_addr timer callback
The timer callback reads entry->retrans_times outside pm.lock to decide
whether to call mptcp_pm_subflow_established(). Since
mptcp_pm_announced_del_timer() can concurrently set retrans_times =
ADD_ADDR_RETRANS_MAX under pm.lock, a race condition exists.

I discovered this issue while studying the code. AI tools helped me to
verify the issue can potentially happen under race conditions.

Use a local 'retransmit' flag set inside pm.lock to capture whether
retransmission is still possible when the lock is taken. This allows to
call mptcp_pm_subflow_established() accordingly, and not depending on
the situation that can be different when checked outside the pm.lock.

Fixes: 348d5c1dec ("mptcp: move to next addr when timeout")
Cc: stable@vger.kernel.org
Signed-off-by: Qing Luo <luoqing@kylinos.cn>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20260803-net-mptcp-misc-fixes-7-2-rc6-v2-4-b8f496d71664@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-06 08:46:23 -07:00
Matthieu Baerts (NGI0)
900e6d8054 mptcp: remove MPC && MPJ check
After the parent commit ("mptcp: avoid combining some incoming
suboptions"), the parsing step no longer allow to have both the
MP_CAPABLE and MP_JOIN suboptions set together.

These chunks are now unreachable, these checks can then be removed.

Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20260803-net-mptcp-misc-fixes-7-2-rc6-v2-3-b8f496d71664@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-06 08:46:23 -07:00
Matthieu Baerts (NGI0)
b6ee361524 mptcp: avoid combining some incoming suboptions
Some MPTCP suboptions are mutually exclusive according to the RFC8684,
but also because in different places, the code doesn't expect some
combinations to be present. That's specially true for suboptions that
would be present twice, but with different attributes.

The new restrictions are the same as the ones applied on the output
side, with mptcp_write_options. The same rules can be reused with a
small fix: an MP_FASTCLOSE can be used with a DSS when the sender picks
this option [1], which is not the case on Linux. Here are the rules:

  Which options can be used together?

  X: mutually exclusive
  O: often used together
  C: can be used together in some cases
  P: could be used together but we prefer not to (optimisations)

  | Opt: | MPC  | MPJ  | DSS  | ADD  |  RM  | PRIO | FAIL |  FC  |
  |------|------|------|------|------|------|------|------|------|
  | MPC  |------|------|------|------|------|------|------|------|
  | MPJ  |  X   |------|------|------|------|------|------|------|
  | DSS  |  X   |  X   |------|------|------|------|------|------|
  | ADD  |  X   |  X   |  P   |------|------|------|------|------|
  | RM   |  C   |  C   |  C   |  P   |------|------|------|------|
  | PRIO |  X   |  C   |  C   |  C   |  C   |------|------|------|
  | FAIL |  X   |  X   |  C   |  X   |  X   |  X   |------|------|
  | FC   |  X   |  X   |  P   |  X   |  X   |  X   |  X   |------|
  | RST  |  X   |  X   |  X   |  X   |  X   |  X   |  O   |  O   |
  |------|------|------|------|------|------|------|------|------|

The only difference is with the 'P': another stack could send and
ADD_ADDR with other suboptions (DSS, RM_ADDR), and this should be
allowed.

A few points of attention:

 - In theory, an MP_CAPABLE could be used with a RM_ADDR, but there is
   no reason to add it with a SYN. Note that even with a 4th ACK, it
   doesn't seem to be useful, except when IDs are known in advance via
   another channel. Better not to break that.

 - Now, combining both an MP_CAPABLE and an MP_JOIN will no longer
   result to a reject of the two options, but only the second suboption
   is ignored. That seems OK to do that for this unexpected error. At
   least now all inconsistent combinations are handled the same way.
   This could change later in next. This also means the explicit checks
   for having both MPC + MPJ in subflow.c will now be unreachable.
   That's fine, they will be removed in a follow-up patch.

 - In case of conflicting combinations, the extra suboption(s) is/are
   ignored: having such combinations either means the remote peer is
   buggy, or is evil. The simplest action is then taken in this case:
   stop processing the current suboption.

 - In mp_opt->suboptions, there is also a bit reserved to the checksum,
   which can be used in an MP_CAPABLE and a DSS. Each time a DSS option
   can be used in parallel with another option, the checksum can be set,
   so the verification is combined into a new OPTIONS_MPTCP_DSS macro.

 - An MP_CAPABLE ACK can carry a Data-Level Length, and an optional
   Checksum: they are the same as the ones found in a DSS, because a DSS
   cannot be used in parallel to an MP_CAPABLE. Similarly, even if there
   is room, a DSS cannot be used with an MP_JOIN.

Fixes: eda7acddf8 ("mptcp: Handle MPTCP TCP options")
Cc: stable@vger.kernel.org
Link: https://www.rfc-editor.org/rfc/rfc8684.html#section-3.5-5.1 [1]
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20260803-net-mptcp-misc-fixes-7-2-rc6-v2-2-b8f496d71664@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-06 08:46:23 -07:00
Matthieu Baerts (NGI0)
35772b4981 mptcp: options: reset DSS fields in case of unexpected size
A remote peer could send a malformed DSS with a wrong size, followed by
another DSS or MPC + Data. In this case, the first suboption will be
ignored, but leaving some fields written, which could lead to
inconsistency or access uninitialized data.

Explicitly reset the fields that could have been modified in case of
unexpected size.

Link: https://netdev-ai.bots.linux.dev/sashiko/#/patchset/20260728-net-mptcp-misc-fixes-7-2-rc6-v1-0-f7e2d229159d%40kernel.org?part=1
Fixes: 648ef4b886 ("mptcp: Implement MPTCP receive path")
Cc: stable@vger.kernel.org
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20260803-net-mptcp-misc-fixes-7-2-rc6-v2-1-b8f496d71664@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-06 08:46:22 -07:00
Linus Torvalds
fcaeecb8b0 Merge tag 'probes-fixes-v7.2-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull probes selftest fix from Masami Hiramatsu:

 - selftests/ftrace: Refactor eprobes test to fix argument checks

   Refactor the eprobes selftest to get more stable test result by using
   `sys_enter_chdir` instead of `openat` and filter for exact directory
   names

   This resolves test instability after the string pointer handling fix

* tag 'probes-fixes-v7.2-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  selftests/ftrace: refactor eprobes test to fix argument checks
2026-08-06 08:29:59 -07:00