skb_segment calculates 32-bit partial_segs as len / gso_size, and then
assigns it to the 16-bit gso_segs field. The division might overflow in
some edge cases where the SKB is BIG TCP (65536 <= len <= 8*65535), and
gso_size < TCP_MIN_GSO_SIZE = 8. While normally this can't happen due to
TCP_MIN_GSO_SIZE, an AF_PACKET PACKET_VNET_HDR socket could generate
such a malformed packet until the previous patch.
Blocking malformed virtio_net packets was implemented in the previous
patch, but this patch clamps partial_segs in skb_segment itself for more
generic robustness. Should len / gso_size happen to be bigger than
65535 in partial GSO, skb_segment will now just produce more than two
output SKBs, all of which will be valid with gso_segs <= 65535.
In order to catch possible other cases of too many partial_segs, add a
DEBUG_NET_WARN_ON_ONCE when len / gso_size happens to be too big.
Signed-off-by: Alice Mikityanska <alice@isovalent.com>
Link: https://patch.msgid.link/20260822120117.1163423-3-alice.kernel@fastmail.im
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The user can specify any gso_size in a packet crafted with an AF_PACKET
PACKET_VNET_HDR socket, even smaller than TCP_MIN_GSO_SIZE = 8. At the
same time, GSO_MAX_SIZE = 8 * GSO_MAX_SEGS = 8 * 65535. When the user
crafts a packet with gso_size < 8, there is a risk for partial GSO to
overflow the 16-bit gso_segs field when dividing the SKB length by
gso_size.
Adjust gso_size of TCP packets to be at least TCP_MIN_GSO_SIZE = 8. Keep
gso_size of UDP GSO packets, as gso_size=1 is valid and explicitly
tested at tools/testing/selftests/net/tun.c:649.
Fixes: 7c6d2ecbda ("net: be more gentle about silly gso requests coming from user")
Signed-off-by: Alice Mikityanska <alice@isovalent.com>
Suggested-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260822120117.1163423-2-alice.kernel@fastmail.im
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
slip_devs[] stores bare net_device pointers and takes no reference on
them. sl_sync() and sl_alloc() walk that table from slip_open() under
rtnl_lock(), while an entry is dropped by sl_free_netdev(), which
sl_setup() installs as dev->priv_destructor.
priv_destructor is called from netdev_run_todo(), which deliberately
runs with the RTNL semaphore released so that it can sleep while waiting
for the device refcount to drop:
/* Snapshot list, allow later requests */
list_replace_init(&net_todo_list, &list);
__rtnl_unlock();
...
if (dev->priv_destructor)
dev->priv_destructor(dev); /* slip_devs[i] = NULL */
if (dev->needs_free_netdev)
free_netdev(dev);
...
/* Free network device */
kobject_put(&dev->dev.kobj);
So rtnl_lock() does not serialise slip_open() against the teardown at
all. sl_sync() can load slip_devs[i] while the entry is still published
and dereference it after netdev_run_todo() has run the destructor and
released the device:
CPU0 (slip_open) CPU1 (slip_close)
unregister_netdev()
rtnl_unlock()
netdev_run_todo()
__rtnl_unlock()
rtnl_lock()
sl_sync()
dev = slip_devs[i]
priv_destructor(dev)
slip_devs[i] = NULL
kobject_put(&dev->dev.kobj)
/* dev is freed */
sl = netdev_priv(dev)
if (sl->tty || sl->leased) /* use-after-free */
BUG: KASAN: use-after-free in sl_sync drivers/net/slip/slip.c:730 [inline]
BUG: KASAN: use-after-free in slip_open+0xef4/0x1210 drivers/net/slip/slip.c:806
Read of size 1 at addr ffff8880712dac71 by task syz-executor.2/6506
CPU: 2 PID: 6506 Comm: syz-executor.2 Not tainted 6.1.134-syzkaller-00260-g0c8fc3469765 #0
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
Call Trace:
sl_sync drivers/net/slip/slip.c:730 [inline]
slip_open+0xef4/0x1210 drivers/net/slip/slip.c:806
tty_ldisc_open+0xa2/0x120 drivers/tty/tty_ldisc.c:433
tty_set_ldisc+0x324/0x720 drivers/tty/tty_ldisc.c:564
tiocsetd drivers/tty/tty_io.c:2428 [inline]
tty_ioctl+0x5f0/0x1530 drivers/tty/tty_io.c:2712
Allocated by task 6502:
alloc_netdev_mqs+0x98/0xfe0 net/core/dev.c:10719
sl_alloc drivers/net/slip/slip.c:756 [inline]
slip_open+0x36d/0x1210 drivers/net/slip/slip.c:817
tty_ldisc_open+0xa2/0x120 drivers/tty/tty_ldisc.c:433
tty_set_ldisc+0x324/0x720 drivers/tty/tty_ldisc.c:564
Freed by task 6497:
device_release+0xa2/0x240 drivers/base/core.c:2507
kobject_put+0x179/0x280 lib/kobject.c:729
netdev_run_todo+0x6c8/0xef0 net/core/dev.c:10509
slip_close+0x166/0x1c0 drivers/net/slip/slip.c:906
tty_ldisc_close+0x113/0x1a0 drivers/tty/tty_ldisc.c:456
tty_ldisc_kill+0x94/0x160 drivers/tty/tty_ldisc.c:614
tty_ldisc_release+0xe3/0x2b0 drivers/tty/tty_ldisc.c:782
tty_release+0xbcc/0xe70 drivers/tty/tty_io.c:1860
Commit e58c191241 ("slip: Fix use-after-free Read in slip_open") fixed
a different source of stale entries - a device left in slip_devs[] after
slip_open() freed it on the registration error path - and does not
address this race, which is why the report survives it.
Drop the entry from ndo_uninit instead. unregister_netdevice() calls
ndo_uninit under RTNL, before the device is queued to netdev_run_todo(),
so an entry that sl_sync() can still see while holding RTNL belongs to a
device that cannot be freed until RTNL is dropped. sl_free_netdev()
stays only for the slip_open() error path, where register_netdevice()
may have failed before ndo_init and ndo_uninit is then not called
either. Both running for the same device is harmless: they run under
the same RTNL section, so the slot cannot have been reused in between.
This also removes the second symptom of the missing exclusion: a
destructor running after sl_alloc() had already handed the slot out to
another channel used to clear a live entry, so sl_sync() stopped at that
NULL, sl_alloc() returned the same index again, and
register_netdevice() failed with -EEXIST because slN was still there.
Reproduced on x86_64 with several threads looping over
open("/dev/ptmx") + ioctl(TIOCSETD, N_SLIP) + close().
Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
Fixes: 5342b77c41 ("slip: Clean up create and destroy")
Cc: stable@vger.kernel.org
Suggested-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Aleksandr Khromov <haa@amicon.ru>
Link: https://patch.msgid.link/20260824100547.164773-1-haa@amicon.ru
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The stmmac TC filtering rules have recently gained sanity checks to make
sure the passed keys and their respective masks are aligned with the HW
filtering abilities.
The stmmac selftests failed to pass the mask in the match data for L4
filtering tests, and are now failing consistently with -EINVAL :
$ ethtool -t eth1
[...]
23. L4 DA TCP Filtering -22
24. L4 SA TCP Filtering -22
25. L4 DA UDP Filtering -22
26. L4 SA UDP Filtering -22
Let's pass the ip_proto mask in the l4 filtering tests match data. Found
on imx8mp, which now have passing L4 tests :
$ ethtool -t eth1
[...]
23. L4 DA TCP Filtering 0
24. L4 SA TCP Filtering 0
25. L4 DA UDP Filtering 0
26. L4 SA UDP Filtering 0
While at it, initialize the masks and keys to avoid re-using whatever
was on the stack.
Fixes: 5536d7c843 ("net: stmmac: fix l3l4 filter rejecting unsupported offload requests")
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Link: https://patch.msgid.link/20260825211748.360935-1-maxime.chevallier@bootlin.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The macros TXGBE_INTR_MISC() and WX_INTR_Q() rely on the standard BIT()
macro to generate interrupt masks based on the queue vector index.
On 32-bit architectures, BIT() evaluates to a 32-bit `unsigned long`.
Since the number of queue vectors can be up to 63 on txgbe devices,
performing a left shift of 32 or more results in an integer overflow
and undefined behavior. This causes incorrect interrupt masking and
unmasking logic for both the queue and miscellaneous interrupts on
32-bit systems.
Fix this by replacing BIT() with BIT_ULL() in these macros. This
ensures that the bitwise shift is always performed safely on a 64-bit
`unsigned long long` type, regardless of the underlying architecture.
Fixes: e37546ad1f ("net: wangxun: revert the adjustment of the IRQ vector sequence")
Signed-off-by: Jiawen Wu <jiawenwu@trustnetic.com>
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Link: https://patch.msgid.link/45F5565CE6AC4329+20260824072119.48399-1-jiawenwu@trustnetic.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
tcp_v4_connect() adds a SYN-SENT socket to the ehash before calling
tcp_connect(). If TCP-AO is configured, tcp_connect() first verifies that
a key matches the peer and the bound device's current L3 master.
tcp_ao_connect_init() later resolves the L3 master again and removes keys
which do not match it.
The socket lock does not stabilize the bound device's VRF membership.
Detaching the device from its VRF between the initial validation and the
L3-master calculation in tcp_ao_connect_init() can therefore make the
validation succeed while initialization observes the default L3 domain and
removes the only key. The subsequent AO lookup then fails, so the no-key
path clears tp->ao_info and frees it directly.
The receive path can find the socket in the ehash and load tp->ao_info
under RCU before acquiring the socket lock. A reader which loaded the old
pointer can thus continue into tcp_inbound_ao_hash() after the direct free.
The issue was found during a static audit of TCP-AO object lifetime. An
unprivileged reproducer in self-created user and network namespaces raced
connect() with detaching a veth from its VRF while sending TCP-AO segments.
It triggered the same KASAN report on two fresh boots:
BUG: KASAN: slab-use-after-free in tcp_inbound_ao_hash+0x585/0x19f0
Write of size 8 at addr ffff88800bf88128 by task tcp_ao_vrf_race/232
Call Trace:
tcp_inbound_ao_hash+0x585/0x19f0
tcp_inbound_hash+0x677/0xa80
tcp_v4_rcv+0x1c3e/0x3ab0
Allocated by task 235:
tcp_ao_alloc_info+0x43/0xf0
tcp_ao_add_cmd+0xdf7/0x13b0
do_tcp_setsockopt+0x168c/0x2640
Freed by task 235:
kfree+0x1b8/0x550
tcp_connect+0x252/0x4f00
tcp_v4_connect+0x1114/0x1720
The bad address is 40 bytes inside the freed 128-byte object, matching the
tcp_ao_info counters.key_not_found field. The two runs used 1000 attempts
each, reached the no-key path 366 and 411 times, and produced one and two
KASAN reports respectively. With this change, the same reproducer reached
the no-key path 366 times in 1000 attempts without a KASAN report or oops.
Use tcp_ao_destroy_sock() for the no-key path. It unpublishes the AO info,
updates the socket memory and static-key accounting, and defers the free
until after an RCU grace period.
Also drop the WARN_ON_ONCE() and its stale comment. The VRF detach race
makes the no-key state reachable during normal operation, so it is a
handled condition rather than an impossible assertion. On panic_on_warn
kernels the WARN would turn this handled race into a kernel panic.
Fixes: 248411b8cb ("net/tcp: Wire up l3index to TCP-AO")
Cc: stable@vger.kernel.org
Assisted-by: Codex:gpt-5
Signed-off-by: Qing Ming <a0yami@mailbox.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260825072033.6921-1-a0yami@mailbox.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The LED GPIO pins (GPIO3/4/5, mapped to LED2/LED1/LED0) are only ever
configured as outputs once, in .probe(). But .config_init() restarts
the MD32 MCU via en8811h_restart_mcu() on every call after the first
(priv->mcu_needs_restart), and that restart resets buckpbus-mapped MCU
state, including EN8811H_GPIO_OUTPUT. As a result the LED GPIOs fall
back to inputs after the first event that re-triggers .config_init()
(link renegotiation, ifdown/ifup, resume), and the PHY's LEDs stop
reflecting link/activity state even though they worked right after
probe.
Move the GPIO-as-output configuration from .probe() to the end of
.config_init(), so it is reapplied every time the MCU may have been
restarted.
Fixes: 71e7943011 ("net: phy: air_en8811h: Add the Airoha EN8811H PHY driver")
Suggested-by: Mikhail Zhilkin <csharper2005@gmail.com>
Signed-off-by: Vitaliy Sochnev <sochnev.v.74@gmail.com>
Link: https://patch.msgid.link/20260823130638.1166453-2-sochnev.v.74@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
When the driver is handed a burst of packets, the doorbell is deferred
until the end. If the last packet has a huge number of frags, but fails
to linearize, the doorbell will not be written adding latency on TX for
any packets in the ring and holding their DMA mappings until the next
TX. Note that the queue is not stopped, so this issue would delay
pending BDs until the next TX.
This issue was discovered by Sashiko and reading the code verifies that,
while unlikely, it is possible.
Fix this by jumping to tx_free, which replicates the same pre-existing
logic but also writes the doorbell.
Fixes: b91e821294 ("bnxt_en: Linearize TX SKB if the fragments exceed the max")
Cc: stable@vger.kernel.org
Signed-off-by: Joe Damato <joe@dama.to>
Reviewed-by: Michael Chan <michael.chan@broadcom.com>
Reviewed-by: Andy Gospodarek <gospo@broadcom.com>
Link: https://patch.msgid.link/20260826000234.2031564-1-joe@dama.to
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
IPPROTO_SMC sockets create an internal TCP sock ("clcsock") from the
proto->init hook. When socket creation fails after proto->init has
run - e.g. a cgroup BPF program attached to BPF_CGROUP_INET_SOCK_CREATE
denies the socket - sk_common_release() only invokes sk_prot->destroy
if it is set, but neither smc_inet_prot nor smc_inet6_prot defines it,
and smc_destruct() returns early unless sk_state is SMC_CLOSED. As a
result, every failing socket(AF_INET, SOCK_STREAM, IPPROTO_SMC) call
leaks one tcp_sock, so an unprivileged task able to attach a deny-all
BPF_CGROUP_INET_SOCK_CREATE program to its own cgroup can grow kernel
memory unboundedly.
Add a .destroy hook to both protos that releases the clcsock via
smc_clcsock_release(). smc_sk_init() hashes the sock into the smc
hashinfo before the clcsock is created, and smc_diag dumps walk that
hash dereferencing smc->clcsock without taking clcsock_release_lock,
while sk_common_release() calls .destroy before .unhash. Unhash the
sock before releasing the clcsock, as __smc_release() does, so a
concurrent dump cannot observe the release; the second unhash in
sk_common_release() is a no-op.
Fixes: d25a92ccae ("net/smc: Introduce IPPROTO_SMC")
Reported-by: Abaci <abaci@linux.alibaba.com>
Assisted-by: abaci:qwen3.8-max
Signed-off-by: Yifei Chu <Chuyf26@linux.alibaba.com>
Reviewed-by: Dust Li <dust.li@linux.alibaba.com>
Link: https://patch.msgid.link/178753843966.342810.566471390946765094@linux.alibaba.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
While debugging another issue today, I found out that my TX queue is
reported as stopped for 4294907392 ms (49.7 days), on a machine that
had been up for four minutes.
bnxt_en 0002:01:00.0 eth0: NETDEV WATCHDOG: CPU: 28: transmit queue 23 timed out 4294907392 ms
4294907392 is not an elapsed time. It is the value of jiffies at that
moment: INITIAL_JIFFIES is 4294667296, which leaves jiffies 59 seconds
short of wrapping.
dev_activate() runs transition_one_qdisc() over every TX queue, which
resets trans_start to 0, and then stamps only queue 0 through
netif_trans_update().
Stamp jiffies instead. A queue stopped across dev_activate() now gets a
full watchdog_timeo of grace, and is still reported if it is stopped
that long.
Fixes: 9b36627ace ("net: remove dev->trans_start")
Cc: stable@vger.kernel.org
Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Nicolai Buchwitz <nb@tipi-net.de>
Reviewed-by: Jason Xing <kerneljasonxing@gmail.com>
Link: https://patch.msgid.link/20260825-trans_start-v2-1-286b4d6d70cb@debian.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
decap_and_validate() pulls the outer SRv6 headers and makes the inner
packet the skb network header. The IPv6 control block still contains
values collected while parsing the outer packet, including nhoff and
extension-header flags.
End.DX6 and End.DT6 route the inner IPv6 packet directly to the IPv6
input path. An unprivileged user can reach End.DT6 from a user and net
namespace by installing a local SID and injecting an outer packet with
Hop-by-Hop and Destination Options headers followed by an SRH and a
minimal inner IPv6 packet.
The outer extension headers leave a large nhoff in IP6CB. After
decapsulation, ip6_protocol_deliver_rcu() uses that stale offset on the
inner packet and reads beyond the skb head. KASAN reports:
BUG: KASAN: slab-out-of-bounds in ip6_protocol_deliver_rcu
ip6_protocol_deliver_rcu+0x1118/0x1450
ip6_input_finish+0x11b/0x240
seg6_local_input_core+0xed/0x2e0
lwtunnel_input+0x1e9/0x4e0
ipv6_rthdr_rcv+0x525f/0x6c50
ip6_protocol_deliver_rcu+0xcb7/0x1450
Before clearing IP6CB for an inner IPv6 packet, save its incoming
interface index and L3 slave state. Restore both after the clear and set
nhoff to the inner IPv6 base-header nexthdr field.
Use IP6CB(skb)->iif rather than skb->skb_iif because VRF processing can
replace skb_iif with the L3 master while IP6CB keeps the receiving
interface. Preserve IP6SKB_L3SLAVE for the same reason.
Fixes: d7a669dd2f ("ipv6: sr: add helper functions for seg6local")
Cc: stable@vger.kernel.org
Reported-by: Vega <vega@nebusec.ai>
Signed-off-by: Zhiling Zou <zhilinz@nebusec.ai>
Reviewed-by: Andrea Mayer <andrea.mayer@uniroma2.it>
Signed-off-by: David S. Miller <davem@davemloft.net>
teql_master_xmit() sets skb->dev = slave before calling the slave's
ndo_start_xmit(), but never restores it when that transmit fails. The
skb then walks on to the next slave still pointing at the previous one.
If a later slave has no resolved neighbour, teql_resolve() hands the skb
to neigh_event_send(), which queues it on that neighbour's arp_queue
with the stale skb->dev. skb->dev holds no reference, so deleting the
previous slave frees the net_device while the skb is still queued.
Whatever runs next on that skb - arp_error_report() on timeout, or
neigh_direct_output() -> dev_queue_xmit() once the neighbour resolves -
causes a UAF like the one below:
BUG: KASAN: slab-use-after-free in __icmp_send (net/ipv4/icmp.c:914 (discriminator 2))
Read of size 4 at addr ffff888106e100b0 by task flood_packet/527
CPU: 0 UID: 0 PID: 527 Comm: flood_packet Not tainted 7.2.0-rc6-g594d90519502 #1 PREEMPT(lazy)
Hardware name: QEMU Ubuntu 24.04 PC v2 (i440FX + PIIX, arch_caps fix, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Call Trace:
<IRQ>
dump_stack_lvl (lib/dump_stack.c:94 lib/dump_stack.c:120)
print_report (mm/kasan/report.c:378 mm/kasan/report.c:482)
? __pfx__raw_spin_lock_irqsave (./include/asm-generic/qrwlock.h:122 (discriminator 4))
? __icmp_send (net/ipv4/icmp.c:914 (discriminator 2))
kasan_report (mm/kasan/report.c:595)
? __icmp_send (net/ipv4/icmp.c:914 (discriminator 2))
__icmp_send (net/ipv4/icmp.c:914 (discriminator 2))
[...]
ipv4_link_failure (net/ipv4/route.c:1251 net/ipv4/route.c:1258)
? __pfx_ipv4_link_failure (./include/linux/skbuff.h:4327)
? _raw_write_lock (./include/linux/instrumented.h:55 ./include/linux/atomic/atomic-instrumented.h:1301 ./include/asm-generic/qrwlock.h:98 ./include/linux/rwlock_api_smp.h:230 kernel/locking/spinlock.c:304)
? __pfx__raw_write_lock (kernel/locking/spinlock.c:175)
arp_error_report (./include/net/dst.h:438 net/ipv4/arp.c:296)
neigh_invalidate (net/core/neighbour.c:1077)
neigh_timer_handler (net/core/neighbour.c:1169)
[...]
Allocated by task 505:
kasan_save_stack (mm/kasan/common.c:57)
kasan_save_track (mm/kasan/common.c:78)
__kasan_kmalloc (mm/kasan/common.c:398 mm/kasan/common.c:415)
__kvmalloc_node_noprof (./include/linux/kasan.h:263 mm/slub.c:5334 mm/slub.c:6905)
alloc_netdev_mqs (net/core/dev.c:12055 (discriminator 2))
rtnl_create_link (net/core/rtnetlink.c:3721)
rtnl_newlink (net/core/rtnetlink.c:3903 net/core/rtnetlink.c:4044 net/core/rtnetlink.c:4159)
rtnetlink_rcv_msg (net/core/rtnetlink.c:7076)
[...]
Freed by task 536:
kasan_save_stack (mm/kasan/common.c:57)
kasan_save_track (mm/kasan/common.c:78)
kasan_save_free_info (mm/kasan/generic.c:584)
__kasan_slab_free (mm/kasan/common.c:253 mm/kasan/common.c:285)
kfree (./include/linux/kasan.h:235 mm/slub.c:2677 mm/slub.c:6377 mm/slub.c:6692)
device_release (drivers/base/core.c:2636)
kobject_put (lib/kobject.c:689 lib/kobject.c:720 ./include/linux/kref.h:65 lib/kobject.c:737)
netdev_run_todo (net/core/dev.c:11756)
rtnl_dellink (net/core/rtnetlink.c:157 ./include/linux/rtnetlink.h:135 net/core/rtnetlink.c:3651)
rtnetlink_rcv_msg (net/core/rtnetlink.c:7076)
[...]
Fix this by restoring skb->dev to the master at the end of each slave's
iteration.
Fixes: 0cc0c2e661 ("net/sched: teql: fix NULL pointer dereference in iptunnel_xmit on TEQL slave xmit")
Reported-by: Vega <vega@nebusec.ai>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Victor Nogueira <victor@mojatatu.com>
Link: https://patch.msgid.link/20260824115928.4099988-1-victor@mojatatu.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Jun Yang says:
====================
sctp: handle wrapped and duplicate RECONF responses
Fix response sequence zero lookup first, then make RECONF response
handling idempotent with an outstanding-request bitmask.
====================
Link: https://patch.msgid.link/20260824081832.98717-1-juny24602@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Jamal Hadi Salim says:
====================
net: sched: fix quantum/mtu overflow in fq, fq_codel, sch_codel, fq_pie, hhf, sfq
Several qdiscs derive their per-flow quantum or CoDel mtu from
psched_mtu() without an overflow or zero clamp, which can drive the
dequeue/credit-refill loop into a soft lockup or silently disable the
AQM. vega@nebusec.ai provided reports and PoCs for the following qdiscs:
sch_fq, sch_fq_codel, sch_fq_pie, sch_hhf, and sch_sfq.
sch_codel was found by inspection for the same pattern. It's TheLinuxWay
(i.e cutnpaste code from somewhere for your new feature) and the AIs
are having a lot of fun finding patterns. We must overcome!
Clamp the quantum (and, for the codel family, the cparams/params mtu)
to a sane range at init/change time so the dequeue loops terminate and
the AQM stays armed. The clamps live in the init/change paths, not the
per-packet fast path, so no hot-path cost is added for a configuration
issue.
This series depends on "net/sched: bound qdisc_pkt_len to prevent qdisc
soft lockup", which caps qdisc_pkt_len() at GSO_MAX_SIZE in
__qdisc_calculate_pkt_len(). That cap closes the fq_codel TCA_STAB
backlog-wrap vector (qdisc_pkt_len inflated to ~1 GiB wrapping the u32
per-flow backlog to 0 and NULL-derefing in fq_codel_drop()); with it
upstream this series no longer needs the fq_codel_drop() hardening hunk
that the earlier respin carried. The five quantum/mtu fixes here are
psched_mtu()-driven and orthogonal to the qdisc_pkt_len() cap.
Q: Why not bound the MTU at the source instead? dummy's max_mtu == 0 is
intentional (dev_validate_mtu() treats 0 as unbounded), other drivers
can legitimately advertise large MTUs, and qdiscs must not trust
psched_mtu() regardless.
Conditions to recreate the bug: a device whose MTU (plus
hard_header_len) wraps 2 * psched_mtu() or psched_mtu() into the sign
bit (e.g. a dummy device with max_mtu == 0 accepting a huge MTU).
Requires CAP_NET_ADMIN in a user namespace.
====================
Link: https://patch.msgid.link/20260822195509.112717-1-jhs@mojatatu.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
sfq_init() sets q->quantum = psched_mtu(qdisc_dev(sch)) (unsigned). A
device with a huge MTU (e.g. dummy with max_mtu == 0 accepting MTU
2147483634) makes psched_mtu() return 0x80000000, so slot->allot = INT_MIN
and INT_MIN + INT_MIN toggles between INT_MIN and 0 forever, spinning
sfq_dequeue() under the qdisc lock.
Clamp the quantum to [256, 1 << 20] so the refill loop terminates. The
lower bound also covers q->quantum == 0 (psched_mtu() returning 0),
which spins sfq_dequeue() identically. sfq_change() already rejects a
negative quantum, so only the init path was exposed.
Conditions to recreate the bug: a device whose MTU (plus
hard_header_len) wraps psched_mtu() into the sign bit (e.g. a dummy
device with max_mtu == 0 accepting MTU 2147483634). Requires
CAP_NET_ADMIN in a user namespace.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reported-by: vega@nebusec.ai
Tested-by: Victor Nogueira <victor@mojatatu.com>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://patch.msgid.link/20260822195509.112717-7-jhs@mojatatu.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
hhf_init() sets q->quantum = psched_mtu(qdisc_dev(sch)) with no overflow
check. A device with a huge MTU (e.g. dummy with max_mtu == 0 accepting
MTU 2147483634) makes weight * quantum overflow the signed deficit in
hhf_dequeue(), spinning forever.
Clamp q->quantum before hhf_change() so both the opt and !opt paths see
a sane quantum. Without this, bare "tc qdisc add ... hhf" succeeds with
a clamped quantum but "tc qdisc add ... hhf limit 1000" (any option
present) fails with -EINVAL because hhf_change() re-validates the
unclamped default (sch_hhf.c:559). 256 matches fq_codel's floor and is
a sane minimum for a DRR quantum.
Conditions to recreate the bug: a device whose MTU (plus
hard_header_len) wraps psched_mtu() into the sign bit (e.g. a dummy
device with max_mtu == 0 accepting MTU 2147483634). Requires
CAP_NET_ADMIN in a user namespace.
Fixes: 10239edf86 ("net-qdisc-hhf: Heavy-Hitter Filter (HHF) qdisc")
Reported-by: vega@nebusec.ai
Tested-by: Victor Nogueira <victor@mojatatu.com>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://patch.msgid.link/20260822195509.112717-6-jhs@mojatatu.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
fq_pie_init() sets q->quantum = psched_mtu(qdisc_dev(sch)) without
clamping. A device with a huge MTU (e.g. dummy with max_mtu == 0
accepting MTU 2147483634) makes psched_mtu() return 0x80000000, which
overflows the signed flow->deficit to INT_MIN in fq_pie_qdisc_dequeue(),
causing an infinite loop and soft lockup. Emulate fq_pie_policy which
is already bounded to [1, 1 << 20]; clamp the default to [256, 1 << 20].
256 matches fq_codel's floor and is a sane minimum for a DRR quantum.
Conditions to recreate the bug: a device whose MTU (plus
hard_header_len) wraps psched_mtu() into the sign bit (e.g. a dummy
device with max_mtu == 0 accepting MTU 2147483634). Requires
CAP_NET_ADMIN in a user namespace.
Fixes: ec97ecf1eb ("net: sched: add Flow Queue PIE packet scheduler")
Reported-by: vega@nebusec.ai
Tested-by: Victor Nogueira <victor@mojatatu.com>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://patch.msgid.link/20260822195509.112717-5-jhs@mojatatu.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
codel_init() sets q->params.mtu = psched_mtu(qdisc_dev(sch)) without
clamping. A device with a huge MTU (e.g. dummy with max_mtu == 0
accepting MTU 2147483634) makes psched_mtu() return 0x80000000. In
codel_should_drop() the test "*backlog <= params->mtu" then compares
the backlog against ~2 GiB; with the default sch->limit of
DEFAULT_CODEL_LIMIT (1000) packets the backlog can never reach it, so
the test is always true and CoDel is silently and completely disabled
i.e no drops, no ECN marking, codel degrades to a tail-drop FIFO.
codel_change() never updates params.mtu, so the init path is the only
place to clamp it. Constrain to [256, 1 << 20], matching the fq_codel
bound; 256 is a sane floor that only makes CoDel slightly more willing
to act on very small queues, which is the safe direction.
Conditions to recreate the bug: a device whose MTU (plus
hard_header_len) wraps psched_mtu() into the sign bit (e.g. a dummy
device with max_mtu == 0 accepting MTU 2147483634). Requires
CAP_NET_ADMIN in a user namespace.
Fixes: 76e3cc126b ("codel: Controlled Delay AQM")
Reported-by: vega@nebusec.ai
Tested-by: Victor Nogueira <victor@mojatatu.com>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://patch.msgid.link/20260822195509.112717-4-jhs@mojatatu.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
fq_codel_init() sets q->quantum = psched_mtu(qdisc_dev(sch)) without
clamping. A device with a huge MTU (e.g. dummy with max_mtu == 0
accepting MTU 2147483634) makes psched_mtu() return 0x80000000, which
overflows the signed flow->deficit to INT_MIN in fq_codel_dequeue(),
causing an infinite loop and soft lockup. Emulate fq_codel_change()
and constrain to [256, FQ_CODEL_QUANTUM_MAX].
The same unclamped psched_mtu() is assigned to q->cparams.mtu a bit
below, and fq_codel_change() never updates it. codel_should_drop()
tests "*backlog <= params->mtu"; with mtu == 0x80000000 (~2 GiB) and
the default 32 MiB memory_limit, the test is always true, so CoDel is
silently and completely disabled (no drops, no ECN). Declare a single
clamped mtu and assign both q->quantum and q->cparams.mtu from it,
which also removes the double psched_mtu() call.
Conditions to recreate the bug: a device whose MTU (plus
hard_header_len) wraps psched_mtu() into the sign bit (e.g. a dummy
device with max_mtu == 0 accepting MTU 2147483634). Requires
CAP_NET_ADMIN in a user namespace.
Fixes: 4b549a2ef4 ("fq_codel: Fair Queue Codel AQM")
Reported-by: vega@nebusec.ai
Tested-by: Victor Nogueira <victor@mojatatu.com>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://patch.msgid.link/20260822195509.112717-3-jhs@mojatatu.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
fq_init() computes quantum = 2 * psched_mtu() and initial_quantum = 10 *
psched_mtu() with no overflow check. A device with a huge MTU (e.g. dummy
with max_mtu == 0 accepting MTU 2147483634) makes psched_mtu() return
0x80000000; the 2 * and 10 * multiplications wrap to 0 in 32-bit
arithmetic, so q->quantum == 0. Then in fq_dequeue() the credit-refill
loop adds 0 to f->credit (which stays <= 0) and goto begin loops
forever under the qdisc lock, creating a soft lockup.
Clamp psched_mtu() to [1, 1 << 20] before multiplying so the product
cannot wrap, then cap the result at 1 << 20, matching the bound already
enforced on TCA_FQ_QUANTUM in fq_change().
Conditions to recreate the bug: a device whose MTU (plus
hard_header_len) is large enough that 2 * psched_mtu() wraps (e.g. a
dummy device with max_mtu == 0 accepting MTU 2147483634). Requires
CAP_NET_ADMIN in a user namespace.
Fixes: afe4fd0624 ("pkt_sched: fq: Fair Queue packet scheduler")
Reported-by: vega@nebusec.ai
Tested-by: Victor Nogueira <victor@mojatatu.com>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://patch.msgid.link/20260822195509.112717-2-jhs@mojatatu.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
virtio_vsock_remove() stops the virtqueues and then flushes each work
item before freeing the enclosing virtio_vsock. The current order does
not account for dependencies between those items: tx_work may queue
send_pkt_work, and send_pkt_work may queue rx_work.
In particular, send_pkt_work can set restart_rx and release tx_lock.
The remove path can then stop the queues and flush rx_work before
send_pkt_work queues it. Although the later send_pkt_work flush waits
for that producer to finish, nothing waits for the newly queued rx_work,
so kfree(vsock) can race with it.
KASAN reported:
BUG: KASAN: slab-use-after-free in
virtio_transport_rx_work+0x487/0x4b0
Read of size 8 at addr ffff888114c2b008 by task kworker/1:1/47
Workqueue: virtio_vsock virtio_transport_rx_work
Call Trace:
virtio_transport_rx_work+0x487/0x4b0
process_one_work+0x688/0x1120
worker_thread+0x45b/0xd10
Allocated by task 1:
virtio_vsock_probe+0xef/0x6b0
Freed by task 84:
kfree+0x131/0x3c0
virtio_vsock_remove+0xd1/0x100
Flush the works in producer-to-consumer order. virtio_vsock_vqs_del()
has already disabled the queue callbacks and cleared the run flags, so
after tx_work and send_pkt_work are drained, no source remains that can
queue rx_work after its flush.
Fixes: 0ea9e1d3a9 ("VSOCK: Introduce virtio_transport.ko")
Cc: stable@vger.kernel.org
Signed-off-by: Chengfeng Ye <nicoyip.dev@gmail.com>
Link: https://patch.msgid.link/20260822164556.3750959-1-nicoyip.dev@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Currently, preinit_net() does two things:
(1) call ns_common_init() which might fail
(2) initialize resources which does not fail
However, preinit_net() is returning early when (1) fails, and copy_net_ns()
is jumping to the dec_ucounts: label. As a result, resources allocated by
net_alloc() are leaking. We need to call key_remove_domain() and
net_passive_dec() in order to release resources allocated by net_alloc().
We cannot simply jump to the put_userns: label when preinit_net() failed,
for (2) is not yet done. But we can reorder (1) and (2), for there is no
dependency between (1) and (2). Therefore, this patch decouples (1) from
preinit_net() and changes preinit_net() back to a void function, and calls
ns_common_init() after preinit_net() succeeded. Then, we can jump to
immediately after ns_common_free() of the put_userns: label.
Reported-by: sashiko (no mail address)
Closes: https://sashiko.dev/#/patchset/af7dabf3-d0d7-46dc-a878-e1715b3c9ac6%40I-love.SAKURA.ne.jp
Fixes: 08027f6b79 ("net: use ns_common_init()")
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Link: https://patch.msgid.link/c182cf90-1ed7-435b-88f7-9f00e88a0487@I-love.SAKURA.ne.jp
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
When skb_orphan_frags() throws -ENOMEM, skb_copy_ubufs() may have
already reallocated and replaced 'from->head'. Accessing from->head to
drop the old refcount leaks the original head page, and erroneously
puts an unrelated new buffer. Use the local 'page' tracker variable
instead to drop the reference properly.
Fixes: 36d5fe6a00 ("core, nfqueue, openvswitch: Orphan frags in skb_zerocopy and handle errors")
Signed-off-by: Mina Almasry <almasrymina@google.com>
Link: https://patch.msgid.link/20260823183602.1051453-2-almasrymina@google.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
sctp_process_strreset_outreq(), sctp_process_strreset_addstrm_out() and
sctp_process_strreset_resp() complete a pending stream reconfiguration
request by stopping the reconf timer on the transport it was sent on:
t = asoc->strreset_chunk->transport;
if (timer_delete(&t->reconf_timer))
sctp_transport_put(t);
chunk->transport is assigned by __sctp_packet_append_chunk() when the
chunk is appended to an outbound packet, and sctp_outq_flush_ctrl() arms
the reconf timer at that same point. A request already published in
asoc->strreset_chunk but not yet transmitted has neither, so completing
it dereferences NULL.
Two ways to get there. sctp_send_asconf_del_ip() sets
asoc->src_out_of_asoc_ok without sending anything when the address being
removed is the association's last one, and sctp_outq_flush_ctrl() then
leaves every non-ASCONF control chunk queued; as only
sctp_process_asconf_ack() clears that flag, it persists. An unprivileged
process that removes such an address and then asks for a stream reset
panics the kernel from softirq. A peer needs neither ASCONF nor local
help: sctp_cmd_interpreter() uncorks the outqueue only once the whole
packet has been processed, so a reply built while walking a RECONF chunk
stays untransmitted for the rest of that walk, and one RECONF chunk
carrying [Incoming SSN Reset Request, Outgoing SSN Reset Request,
Response] -- or two RECONF chunks in one packet -- reaches the same
dereference.
KASAN: null-ptr-deref in range [0x00000000000001e8-0x00000000000001ef]
RIP: 0010:timer_delete+0x67/0x110
Call Trace:
<IRQ>
sctp_process_strreset_addstrm_out (net/sctp/stream.c:832)
sctp_sf_do_reconf (net/sctp/sm_statefuns.c:4212)
sctp_do_sm (net/sctp/sm_sideeffect.c:1172)
sctp_assoc_bh_rcv (net/sctp/associola.c:1044)
sctp_rcv (net/sctp/input.c:243)
ip_local_deliver (net/ipv4/ip_input.c:262)
process_backlog (net/core/dev.c:6680)
</IRQ>
A response can only acknowledge a request that was actually sent, so do
not match asoc->strreset_chunk while chunk->transport is NULL. Guarding
the lookup covers all three completion sites.
Fixes: 8105447645 ("sctp: implement receiver-side procedures for the Outgoing SSN Reset Request Parameter")
Cc: stable@vger.kernel.org
Reported-by: Xiang Mei <xmei5@asu.edu>
Suggested-by: Xin Long <lucien.xin@gmail.com>
Assisted-by: Claude:claude-opus-5
Signed-off-by: Weiming Shi <bestswngs@gmail.com>
Acked-by: Xin Long <lucien.xin@gmail.com>
Link: https://patch.msgid.link/20260823172857.896146-2-bestswngs@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
syzbot reported a warning in skb_network_header_len() triggered
by tcf_skbmod_act():
!skb_transport_header_was_set(skb)
WARNING: CPU: 0 PID: 14949 at include/linux/skbuff.h:3243 skb_network_header_len include/linux/skbuff.h:3243 [inline]
WARNING: CPU: 0 PID: 14949 at net/sched/act_skbmod.c:55 tcf_skbmod_act+0xfe8/0x1810 net/sched/act_skbmod.c:55
There are a few issues in tcf_skbmod_act():
1. Calling skb_network_header_len() assumes skb->transport_header is set,
which is not guaranteed when tcf_skbmod_act() runs at TC ingress.
2. Unconditionally calling skb_mac_header_len() at the beginning of
tcf_skbmod_act() triggers a warning on L3 devices (e.g. TUN) where the
MAC header is unset, evaluating to an underflowed garbage length.
3. On TC ingress, skb->data points to the network header. Adding the MAC
header length to the IP header length causes skb_ensure_writable() to
request more bytes than the actual IP packet length, dropping valid
short packets (e.g. 28-byte UDP/IPv4 packets).
Fix these by:
- Using skb_network_offset(skb) + sizeof(struct iphdr/ipv6hdr) for
SKBMOD_F_ECN so that the required length is correctly calculated on
both ingress (offset == 0) and egress (offset == mac_len).
- Setting max_edit_len to ETH_HLEN for Ethernet header modifications
after validating ARPHRD_ETHER.
Fixes: 56af5e749f ("net/sched: act_skbmod: Add SKBMOD_F_ECN option support")
Reported-by: syzbot+1d56f14f95c0480cfdc9@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/6a8b39c0.dbb3a75c.13dd47.0051.GAE@google.com/T/#u
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260823182241.1958695-1-edumazet@google.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Found with syzkaller and a local syzbot instance running on top of a
netdevsim TLS offload emulation; tls_device.c is otherwise only reachable
on a machine with a NIC that implements the offload.
tls_push_data() only checks whether the open record still has room for
another frag at the bottom of its loop, and the MSG_MORE early break
skips that check. The record survives to the next syscall with the frag
count it already had, and tls_append_frag() does not check either, so
with TLS_TX_ZEROCOPY_RO every splice(SPLICE_F_MORE) of a byte or two adds
a non-coalescing pipe page and num_frags walks off the end of
tls_record_info.frags[MAX_SKB_FRAGS]. Once the record is pushed,
tls_push_record() runs the same index over sg_tx_data[MAX_SKB_FRAGS] and
the sg_set_page() writes land on the destruct_work that follows it, which
the workqueue then calls.
The byte limit is fine because copy drops to 0 and the loop falls through
to the same check; the frag count has no such feedback.
Push the record rather than keep a full one open, which is what a plain
TCP socket does - tcp_sendmsg_locked() uses tcp_mark_push() and
new_segment in both the copy and the MSG_SPLICE_PAGES paths, and tls_sw
already sets full_record when the sk_msg ring fills up, MSG_MORE or not.
BUG: KASAN: slab-out-of-bounds in tls_append_frag ( net/tls/tls_device.c:269)
Write of size 8 at addr ffff8881104d1530 by task tls_oob/450
CPU: 2 UID: 0 PID: 450 Comm: tls_oob Not tainted 7.2.0-rc7+ #329 PREEMPT
Call Trace:
<TASK>
dump_stack_lvl (lib/dump_stack.c:94 lib/dump_stack.c:120)
print_report (mm/kasan/report.c:378 mm/kasan/report.c:482)
kasan_report (mm/kasan/report.c:595)
tls_append_frag (net/tls/tls_device.c:269)
tls_push_data (net/tls/tls_device.c:518)
tls_device_sendmsg (net/tls/tls_device.c:583)
inet_sendmsg (net/ipv4/af_inet.c:865)
sock_sendmsg (net/socket.c:775 net/socket.c:790 net/socket.c:813)
splice_to_socket (fs/splice.c:884)
do_splice (fs/splice.c:936 fs/splice.c:1349)
__do_splice (fs/splice.c:1431)
__x64_sys_splice (fs/splice.c:1634 fs/splice.c:1616)
do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121)
</TASK>
and, once the record is pushed:
UBSAN: array-index-out-of-bounds in net/tls/tls_device.c:300:24
index 18 is out of range for type 'skb_frag_t [17]'
UBSAN: array-index-out-of-bounds in net/tls/tls_device.c:301:41
index 18 is out of range for type 'scatterlist [17]'
UBSAN: array-index-out-of-bounds in net/tls/tls_device.c:302:39
index 18 is out of range for type 'scatterlist [17]'
UBSAN: array-index-out-of-bounds in net/tls/tls_device.c:307:38
index 26 is out of range for type 'scatterlist [17]'
kernel tried to execute NX-protected page - exploit attempt? (uid: 0)
BUG: unable to handle page fault for address: ffffea000411a680
#PF: supervisor instruction fetch in kernel mode
#PF: error_code(0x0011) - permissions violation
Oops: Oops: 0011 [#1] SMP KASAN PTI
Workqueue: ktls_device_destruct 0xffffea000411a680
RIP: 0010:0xffffea000411a680
Call Trace:
<TASK>
worker_thread (kernel/workqueue.c:3405 kernel/workqueue.c:3486)
kthread (kernel/kthread.c:436)
ret_from_fork (arch/x86/kernel/process.c:158)
ret_from_fork_asm (arch/x86/entry/entry_64.S:245)
</TASK>
Fixes: e8f6979981 ("net/tls: Add generic NIC offload infrastructure")
Cc: stable@vger.kernel.org
Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Link: https://patch.msgid.link/20260823084758.20936-1-jiayuan.chen@linux.dev
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Norbert Szetei says:
====================
net: don't strip zerocopy frag markers from a forwarded skb
queue_userspace_packet() calls skb_tx_error() on the packet skb in its
error path, but it only borrows that skb: on the OVS_ACTION_ATTR_USERSPACE
action path do_execute_actions() ignores output_userspace()'s return value
and keeps forwarding the same skb through the flow's remaining actions.
skb_tx_error() completes the zerocopy uarg and clears SKBFL_ALL_ZEROCOPY,
and with it SKBFL_SHARED_FRAG.
For a MSG_ZEROCOPY skb carrying page-cache frags, SKBFL_SHARED_FRAG is
what makes esp_input() skb_cow_data() instead of taking the in-place AEAD
path. Once it is stripped, a later local ESP delivery decrypts in place
over pages the sender still shares with the page cache.
Patch 1 moves the skb_tx_error() into the one path that does drop the
packet, the "default" arm of ovs_dp_process_packet()'s switch(error).
Patch 2 removes a second such strip, in skb_zerocopy(), which calls
skb_tx_error() on its source when skb_orphan_frags() fails. A copy helper
should not perform a destructive action on its source, and both callers
already report the error on their own drop path. MSG_ZEROCOPY skbs cannot
reach that one -- SKBFL_DONT_ORPHAN makes skb_orphan_frags() return early
-- but producers that do not set that flag, such as vhost-net, can.
Patch 3 is new in v2. It stops skb_tx_error() from touching skb_shinfo()
state that is shared with clones, so patch 1's new call site cannot reach
a live skb either. For a non-last OVS_ACTION_ATTR_RECIRC action
clone_execute() sends a skb_clone() into ovs_dp_process_packet() while
do_execute_actions() keeps forwarding the original, and skb_clone() does
not privatise the frags for these skbs -- skb_orphan_frags() returns early
on SKBFL_DONT_ORPHAN -- so a flow miss on the clone strips
SKBFL_SHARED_FRAG from the packet still in flight. Confirmed on a KASAN
build with a flow matching recirc_id 0 and actions RECIRC(1),OUTPUT(0):
with patches 1 and 2 applied it still reproduces the page-cache write,
with patch 3 on top it no longer does (5/5 runs). A kprobe on
skb_tx_error() shows the datapath drop path is still reached in both
cases, so the difference is the guard and not the reproducer.
As Ilya noted, that makes patch 3 the general fix -- an skb can enter any
skb_tx_error() caller already cloned elsewhere in the stack -- while
patches 1 and 2 keep the callers from acting on an skb they do not own.
Removing skb_tx_error() altogether looks like the right long-term cleanup
and is planned as a net-next follow-up.
v3: https://lore.kernel.org/netdev/F3B9E5BA-0AC1-4AD1-A7D9-F38033304270@doyensec.com/
v2: https://lore.kernel.org/netdev/AD1B7BEE-C04C-4A1B-982C-8385F1908911@doyensec.com/
v1: https://lore.kernel.org/netdev/8063260C-05C9-4997-B9B6-2135063C4858@doyensec.com/
====================
Link: https://patch.msgid.link/4B5CCA6E-2C49-4F86-8C4E-E1BE15C16C0A@doyensec.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
skb_tx_error() completes the zerocopy uarg and clears
SKBFL_ALL_ZEROCOPY, and skb_zcopy_downgrade_managed() clears
SKBFL_MANAGED_FRAG_REFS. Both live in skb_shinfo(), which every clone
shares, while the caller only owns the reference it is about to drop.
Through a clone it tells the producer its pages are free and drops
SKBFL_SHARED_FRAG for an skb that is still in flight.
Open vSwitch reaches this with a non-last OVS_ACTION_ATTR_RECIRC:
clone_execute() sends a skb_clone() into ovs_dp_process_packet() while
do_execute_actions() keeps forwarding the original, and skb_clone()
does not privatise the frags here -- skb_orphan_frags() returns early
on SKBFL_DONT_ORPHAN. A flow miss on the clone then strips the marker
from the packet still being forwarded, and a later local ESP delivery
decrypts in place over frags it does not own privately.
Skip it for a cloned skb. Nothing is lost: skb_release_data() clears
the zerocopy state once the last reference to the shared data goes.
Fixes: 25121173f7 ("skb: api to report errors for zero copy skbs")
Cc: stable@vger.kernel.org
Suggested-by: Ilya Maximets <i.maximets@ovn.org>
Signed-off-by: Norbert Szetei <norbert@doyensec.com>
Reviewed-by: Ilya Maximets <i.maximets@ovn.org>
Tested-by: Jongmin Jang <payload.jang@gmail.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/CFAB292A-674B-4C14-BB2C-BB8830AD5659@doyensec.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
skb_zerocopy() copies frags from @from into @to. On an
skb_orphan_frags() failure it calls skb_tx_error(@from), a destructive
operation on the source skb the copy helper does not own. That completes
@from's zerocopy uarg and clears SKBFL_ALL_ZEROCOPY, including the
SKBFL_SHARED_FRAG page-ownership marker.
Both callers already report the failure on their own drop path.
nfnetlink_queue does it at nla_put_failure, and Open vSwitch does it in
the flow-miss drop arm of ovs_dp_process_packet(), so nothing is lost by
dropping it here.
On Open vSwitch's OVS_ACTION_ATTR_USERSPACE path the skb is not freed on
this error: do_execute_actions() ignores output_userspace()'s return
value and, unless the upcall was the last action, keeps forwarding the
same skb through the flow's remaining actions. The uarg is completed
while that skb is still in flight, telling the producer its buffers are
free, and SKBFL_SHARED_FRAG is cleared on an skb the rest of the stack
still handles. That flag is what makes esp_input() call skb_cow_data()
instead of decrypting in place, so a later local ESP delivery can
decrypt over frags the skb does not own privately.
Leave error reporting to the callers.
Fixes: 36d5fe6a00 ("core, nfqueue, openvswitch: Orphan frags in skb_zerocopy and handle errors")
Cc: stable@vger.kernel.org
Suggested-by: Ilya Maximets <i.maximets@ovn.org>
Signed-off-by: Norbert Szetei <norbert@doyensec.com>
Reviewed-by: Ilya Maximets <i.maximets@ovn.org>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/6E3A780D-FB87-421F-9964-B1D457D7D106@doyensec.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
queue_userspace_packet() borrows the packet skb -- it only copies it into
a private netlink message (user_skb) and does not own it; on return
do_execute_actions() keeps forwarding it through the flow's remaining
actions. Its error path nevertheless calls skb_tx_error(skb), which via
skb_zcopy_clear() does skb_shinfo(skb)->flags &= ~SKBFL_ALL_ZEROCOPY,
stripping SKBFL_SHARED_FRAG from that live skb (skb_tx_error()'s kerneldoc
says "skb must be freed afterwards").
For a MSG_ZEROCOPY skb carrying page-cache frags, SKBFL_SHARED_FRAG is
what makes esp_input() skb_cow_data() before in-place AEAD; once it is
stripped a later local ESP-in-UDP delivery decrypts in place over pages
the sender does not own -- an unprivileged page-cache write (the
"Fragnesia" primitive).
do_execute_actions() ignores output_userspace()'s return value, so any
action after a failed USERSPACE upcall inherits the stripped skb.
Move the skb_tx_error() to the flow-miss drop path - the "default"
branch of ovs_dp_process_packet()'s switch(error), before kfree_skb().
The call has been here since commit 36d5fe6a00 ("core, nfqueue,
openvswitch: Orphan frags in skb_zerocopy and handle errors") but was
harmless until esp_input() began relying on SKBFL_SHARED_FRAG to gate
in-place decrypt; only then did stripping it on a still-forwarded skb
become a page-cache write primitive.
Fixes: 36d5fe6a00 ("core, nfqueue, openvswitch: Orphan frags in skb_zerocopy and handle errors")
Fixes: f4c50a4034 ("xfrm: esp: avoid in-place decrypt on shared skb frags")
Cc: stable@vger.kernel.org
Assisted-by: Claude:claude-opus-5
Signed-off-by: Norbert Szetei <norbert@doyensec.com>
Reviewed-by: Ilya Maximets <i.maximets@ovn.org>
Tested-by: Jongmin Jang <payload.jang@gmail.com>
Link: https://patch.msgid.link/55A52703-7548-4A55-A9CE-2A37145BDCAD@doyensec.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Luiz Augusto von Dentz says:
====================
bluetooth pull request for net:
Core:
- hci_core: use skb_get() instead of skb_clone() for req_skb
- hci_conn: re-enable advertising only for peripheral role
- hci_event: clear HCI_LE_ADV only on a created connection
- hci_sync: Clear HCI_CMD_PENDING when dropping the last request
- hci_sync: add conditional locking annotations
- hci_sync: do not leak an hci_conn when a second LE connect is rejected
- eir: Fix OOB read in eir_get_service_data()
- mgmt: fix 'hdev->discovery.uuids' NULL dereference
- L2CAP: access chan->conn safely in get/setsockopt
- L2CAP: reject accept queue add unless BT_LISTEN
- L2CAP: fix race l2cap_sock_cleanup_listen() vs. put_chan
- RFCOMM: serialize security confirmation handling
- RFCOMM: serialize session teardown
- RFCOMM: Validate MTU in rfcomm_apply_pn() to prevent infinite loop
- ISO: fix use-after-free of listener socket in iso_conn_ready
Drivers:
- btnxpuart: Validate the FW dump header length
- btnxpuart: Check remote M.2 connector availability before pwrseq
- btmtksdio: Take exclusive ownership of the SKB before TX
- btmtksdio: Fix out-of-bounds DMA read in the TX path
- hci_uart: Fix false success return in hci_uart_setup()
- hci_bcm: fix usage_count leak when autosuspend_delay is negative
- hci_h5: fix usage_count leak when autosuspend_delay is negative
- hci_intel: fix usage_count leak when autosuspend_delay is negative
- btmtk: Do not report success when subsys reset fails
- btmtk: Do not discard the subsystem reset timeout
- btusb: limit RTL8761B BROKEN_EXT_SCAN quirk to 0bda:a728
- hci_bcm4377: Ignore reserved PHY in ext adv reports on BCM4378
* tag 'for-net-2026-08-24' of git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth: (27 commits)
Bluetooth: RFCOMM: serialize session teardown
Bluetooth: do not leak an hci_conn when a second LE connect is rejected
Bluetooth: RFCOMM: serialize security confirmation handling
Bluetooth: btusb: limit RTL8761B BROKEN_EXT_SCAN quirk to 0bda:a728
Bluetooth: hci_uart: Fix false success return in hci_uart_setup()
Bluetooth: RFCOMM: Validate MTU in rfcomm_apply_pn() to prevent infinite loop
Bluetooth: ISO: fix use-after-free of listener socket in iso_conn_ready
Bluetooth: hci_core: use skb_get() instead of skb_clone() for req_skb
Bluetooth: hci_event: clear HCI_LE_ADV only on a created connection
Bluetooth: hci_conn: re-enable advertising only for peripheral role
Bluetooth: hci_bcm4377: Ignore reserved PHY in ext adv reports on BCM4378
Bluetooth: eir: Fix OOB read in eir_get_service_data()
Bluetooth: btnxpuart: Validate the FW dump header length
Bluetooth: hci_sync: add conditional locking annotations
Bluetooth: btnxpuart: Check remote M.2 connector availability before pwrseq
Bluetooth: btmtksdio: Fix out-of-bounds DMA read in the TX path
Bluetooth: btmtksdio: Take exclusive ownership of the SKB before TX
Bluetooth: btmtk: Do not discard the subsystem reset timeout
Bluetooth: btmtk: Do not report success when subsys reset fails
Bluetooth: L2CAP: fix race l2cap_sock_cleanup_listen() vs. put_chan
...
====================
Link: https://patch.msgid.link/20260824180639.3570348-1-luiz.dentz@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
rvu_mbox_init() is called separately for AF-PF mailboxes during probe
and for AF-VF mailboxes when SR-IOV is enabled. Each call used to
allocate a new ng_rvu object, leaking the first allocation when the
pointer was overwritten on the second call.
Sharing one ng_rvu across both paths exposed several teardown bugs:
the error path freed all cn20k mailbox DMA and kfree()d ng_rvu even
when only the failing init type should be unwound, leaving live AF-PF
mailbox memory in use after an AF-VF init failure. mutex_init() was
also re-run on the AF-VF path while AF-PF mailbox handlers could still
hold rvu->mbox_lock. Probe and SR-IOV failure paths did not release
cn20k mailbox DMA either, since cleanup only happened in rvu_remove().
Allocate ng_rvu once with devm_kzalloc(), initialize mbox_lock in the
same block, unwind only the mailbox memory for the failing init type,
and free cn20k mailbox DMA from the probe and pci_enable_sriov()
error paths.
Fixes: e53ee4acb2 ("octeontx2-af: CN20k basic mbox operations and structures")
Signed-off-by: Sai Krishna <saikrishnag@marvell.com>
Signed-off-by: Ratheesh Kannoth <rkannoth@marvell.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260821102337.2989169-1-rkannoth@marvell.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
af_xdp_zc_qidx tracks receive queues using AF_XDP zero-copy and is
allocated during PF/VF probe. Representors and other non-AF_XDP paths
leave the pointer NULL, but several call sites used test_bit() on it
unconditionally.
Switching to devlink eswitch mode creates representors and runs
otx2_init_hw_resources(), which reaches otx2_pool_aq_init() and oopses
when dereferencing the NULL bitmap. Add NULL checks before every
af_xdp_zc_qidx test_bit() use in the RSS, ethtool, XSK, and pool init
paths.
Fixes: efabce2901 ("octeontx2-pf: AF_XDP zero copy receive support")
Signed-off-by: Suman Ghosh <sumang@marvell.com>
Signed-off-by: Geetha sowjanya <gakula@marvell.com>
Signed-off-by: Ratheesh Kannoth <rkannoth@marvell.com>
Link: https://patch.msgid.link/20260821105536.2998765-1-rkannoth@marvell.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
afiucv_hs_rcv() selects a socket from iucv_sk_list by matching four 8-byte
name fields in the transport header alone. No check is made against the
net_device the frame arrived on.
This can cause a frame arriving on any netdev to be delivered to an AF_IUCV
socket. Three problems follow.
First, a frame arriving over HiperSockets can be delivered to a socket
bound to the classic z/VM IUCV transport, which has iucv->hs_dev == NULL.
iucv_sock_bind() takes the classic path whenever the requested userid
matches iucv_userid, even on a guest that also has a HiperSockets device
carrying the same identifier. The child socket created by
afiucv_hs_callback_syn() for such a match inherits hs_dev = NULL and
transport = AF_IUCV_TRANS_HIPER, so the first send() on it returns -ENODEV.
The socket delivered to accept() is unusable.
Second, a frame arriving on one netdev can be delivered to a socket bound
to a different IQD device. Which can lead to
- Accept-queue exhaustion (DoS)
- Attacker-controlled peer identity in the child socket
- Data injection into existing sockets
- Fabric noise on the IQD fabric, where bogus replies are sent
- killing established connections
Third, all AF_IUCV sockets live in init_net, as iucv_sock_alloc() calls
sk_alloc(&init_net, ...). But even frames arriving on netdev devices in a
namespace can be delivered to an IUCV socket. So a process in an
unprivileged user and network namespace holding only the CAP_NET_RAW
capability valid within that namespace can send a raw ETH_P_AF_IUCV frame
on its own lo device and have it matched against init_net sockets.
Fix all three by skipping any socket whose hs_dev does not match the
ingress device. A classic z/VM IUCV socket has hs_dev == NULL; the ingress
dev is never NULL, so classic sockets are skipped automatically. An unbound
HIPER socket also has hs_dev == NULL and is skipped. A bound HIPER socket
is only reachable from the exact IQD device it was bound to. Because hs_dev
is always a device in init_net (iucv_sock_bind() scans
for_each_netdev_rcu(&init_net, ...) exclusively), a frame whose ingress
device belongs to another namespace never matches any socket.
Note that AF_IUCV over HiperSockets provides no per-connection
authentication: no sequence numbers, no TLS, no nonce. The four name fields
identifying a connection are exchanged in plaintext on the shared
HiperSockets segment (VCHID). Any host on the same HiperSockets segment
could spoof any frame type against an existing connection. That is a
protocol-level property unchanged by this patch. The fix reduces the attack
surface to peers present on the same HiperSockets segment.
Fixes: 3881ac441f ("af_iucv: add HiperSockets transport")
Cc: stable@vger.kernel.org
Co-developed-by: Bryam Vargas <hexlabsecurity@proton.me>
Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
Link: https://patch.msgid.link/20260821125501.3718748-1-wintera@linux.ibm.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
rds_cong_map_updated() runs after a peer's congestion map has been
rewritten (by rds_tcp_cong_recv() and rds_ib_cong_recv(), or the
clear-all in the loopback and IB send-completion paths). It bumps
rds_cong_generation and then checks waitqueue_active() on
map->m_waitq and on rds_poll_waitq to decide whether anyone needs
waking. atomic_inc() carries no ordering and waitqueue_active() is a
plain load, so nothing orders the map and generation stores before
the wait queue reads. The waiters do the mirror image: rds_cong_wait()
adds itself to m_waitq and then tests the port bit, and rds_poll()
registers on rds_poll_waitq and then reads the generation. That is
the store-buffering pattern described above waitqueue_active() in
include/linux/wait.h - the updater can observe an empty wait queue
while the waiter still observes the port as congested, and no wake-up
is issued.
rds_cong_wait() is an interruptible sleep with no timeout, so a
sender blocked on a congested port stays blocked until the next
congestion update from that peer arrives or a signal is delivered.
A poll() waiter misses the map-updated notification the same way.
Use wq_has_sleeper(), which is waitqueue_active() preceded by the
required full barrier, as rds_tcp_state_change() already does for
the same pattern.
Fixes: 922cb17a5c ("RDS: Congestion-handling code")
Signed-off-by: Allison Henderson <achender@kernel.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260822052647.88318-1-achender@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
mana_gd_query_max_resources() sizes gc->num_msix_usable from resp.max_msix
and the CPU count, but never from the device MSI-X table. On a 1792 vCPU
M-series VM that yields 1793 while the table has 1024 entries, and
mana_gd_setup_remaining_irqs() then walks indices 1..1792, running off the
end of the region mapped by msix_map_region():
BUG: unable to handle page fault for address: ff8e347f8b99800c
RIP: 0010:msix_prepare_msi_desc+0x7a/0x90
RAX: 0000000000004000 RBX: ff4330cb164ea780 RCX: ff8e347f8b998000
Call Trace:
<TASK>
__msi_domain_alloc_irqs+0x13a/0x440
msi_domain_alloc_irq_at+0x149/0x1b0
mana_gd_setup+0x351/0x890
mana_gd_probe+0x274/0x390
</TASK>
RAX is index 1024 * PCI_MSIX_ENTRY_SIZE, one entry past the table.
msi_insert_desc() does range check the index, but only against the MSI
domain hwsize, which matches the table only for devices on an MSI parent
domain. With a global PCI/MSI domain hwsize is MSI_XA_DOMAIN_SIZE, so
nothing bounds the request.
Cap num_msix_usable with pci_msix_vec_count().
Fixes: 7553911210 ("net: mana: Allocate MSI-X vectors dynamically")
Signed-off-by: Long Li <longli@microsoft.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260821183736.733296-1-longli@microsoft.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
act_ife encapsulates/decapsulates the original Ethernet header and uses
skb->dev->hard_header_len as the length of that header. That is only
correct for Ethernet devices: on a device where hard_header_len does not
match the L2 header that was actually pulled (PPP reports PPP_HDRLEN
while nothing is stripped on ingress), the ingress skb_push()/skb_pull()
use the wrong length and can hit skb_under_panic when headroom is tight.
IFE is Ethernet-only by design - it builds an outer ethhdr, rewrites
h_source/h_dest/h_proto, and calls eth_type_trans() on decode - so
instead of trying to make the offsets work for arbitrary link types,
simply drop packets that do not carry an Ethernet header.
Checking skb->dev->type alone is not enough. We have to cater for a
corner case where mirred can redirect an skb from a non-Ethernet device
to an Ethernet one, and skb->dev then says nothing about the framing the
skb actually has: an skb redirected from ppp0 reaches the target's ingress
hook with mac_len 0 and no Ethernet header at all. So at ingress also
require mac_len to be ETH_HLEN. On egress mac_len is not maintained, so
the device type is all we have; a bogus redirect there yields a malformed
frame rather than an out-of-bounds push, and it would be malformed with or
without IFE.
That corner case is not theoretical - redirecting from ppp0 into a veth
that has an ife encode action on its ingress hook panics without this
patch:
skbuff: skb_under_panic: len:98 put:14 head:ffff88800e410000
data:ffff88800e40fff5 tail:0x57 end:0x640 dev:veth3
kernel BUG at net/core/skbuff.c:214!
Call Trace:
skb_push (net/core/skbuff.c:224 net/core/skbuff.c:2657)
tcf_ife_act (net/sched/act_ife.c:829 net/sched/act_ife.c:874)
tc_run (net/core/dev.c:4463)
netif_receive_skb (net/core/dev.c:6463 net/core/dev.c:6522)
tcf_mirred_to_dev (net/sched/act_mirred.c:248 net/sched/act_mirred.c:328)
tcf_mirred_act (net/sched/act_mirred.c:489)
tc_run (net/core/dev.c:4463)
process_backlog (net/core/dev.c:6728)
With Ethernet framing guaranteed, use ETH_HLEN instead of
hard_header_len.
Fixes: 295a6e06d2 ("net/sched: act_ife: Change to use ife module")
Reported-by: vega@nebusec.ai
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Victor Nogueira <victor@mojatatu.com>
Link: https://patch.msgid.link/20260821164031.32824-1-victor@mojatatu.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
On an of_property_read_u32() failure, rswitch_get_port_node() set port
to NULL and jumped to the out label before releasing the reference the
for_each_available_child_of_node() iterator was holding on it. Once
port was overwritten with NULL, that reference could never be
released since out: only put "ports", the parent node.
Rework the function around for_each_available_child_of_node_scoped()
instead of adding a manual of_node_put(), so the iterator's reference
is dropped automatically on every exit path. Since port is the
function's return value, take an explicit reference with of_node_get()
on the match before breaking out of the loop.
Signed-off-by: Manush Prajwal <manushprajwal555@gmail.com>
Link: https://patch.msgid.link/6a882352.ee10049a.267d65.7a31@mx.google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Wei Fang says:
====================
net: enetc: restore RX ring congestion mode after ring reconfiguration
The RX BD ring congestion mode (CM) enables the ENETC MAC to generate
PAUSE frames when ingress congestion occurs. It is configured only in
the phylink .mac_link_up() callback, which is invoked when the link
status changes.
However, enetc_reconfigure() tears down and re-creates the RX BD rings
at runtime without any link status change, for example when enabling or
disabling PTP RX hardware timestamping. enetc_setup_rxbdr() rebuilds the
RBMR register from zero, which clears the CM bit, and since the link
status does not change, .mac_link_up() is not called again to restore
it. As a result, flow control silently stops working after such a
reconfiguration.
To solve this issue, track the desired CM state in a software flag
ENETC_RXBDR_CM, which is maintained by the .mac_link_up() /
.mac_link_down() callbacks and consulted by enetc_setup_rxbdr() when the
RX BD rings are (re)configured. Both ENETC v1 and ENETC v4 are affected
and are fixed in the same way.
====================
Link: https://patch.msgid.link/20260821064140.1315611-1-wei.fang@oss.nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
ENETC v4 has the same problem as ENETC v1: the RX BD ring congestion
mode (CM) is only configured in the phylink .mac_link_up() callback, so
it is cleared when enetc_reconfigure() rebuilds the RX BD rings at
runtime (for example when enabling or disabling PTP RX hardware
timestamping) without a link status change, and it is never restored.
As a result, the MAC can no longer generate PAUSE frames on ingress
congestion and flow control stops working.
Fix it in the same way as ENETC v1. Track the desired CM state in the
software flag ENETC_RXBDR_CM. Route enetc4_set_tx_pause() through the
shared helper enetc_set_congestion_mode(), which sets or clears the flag
according to tx_pause and updates the ENETC_RBMR_CM bit under si->gen_lock.
When the RX BD rings are (re)enabled, enetc_enable_rxbdr() consults this
flag and restores the CM bit accordingly, so flow control survives ring
reconfiguration even when the link status does not change.
Fixes: f5b9a1cde0 ("net: enetc: add PTP synchronization support for ENETC v4")
Signed-off-by: Wei Fang <wei.fang@nxp.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260821064140.1315611-3-wei.fang@oss.nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The RX ring congestion mode (CM) is only configured in the phylink
.mac_link_up() callback enetc_pl_mac_link_up(), which sets the
ENETC_RBMR_CM bit when tx_pause is enabled. This callback runs only when
the link status changes.
However, enetc_reconfigure() tears down and re-creates the RX BD rings at
runtime without any link status change, for example when attaching or
detaching an XDP program, or when enabling/disabling PTP RX hardware
timestamping. The rings are rebuilt from a cleared RBMR, so the CM bit is
lost. Since the link status does not change, enetc_pl_mac_link_up() is
not called again and the CM bit is never restored.
As a result, the ENETC MAC can no longer generate PAUSE frames on ingress
congestion, and flow control stops working after such a reconfiguration.
Track the desired CM state in a software flag ENETC_RXBDR_CM. Set or clear
this flag in enetc_pl_mac_link_up() according to tx_pause. When the RX BD
rings are (re)enabled, enetc_enable_rxbdr() consults this flag and restores
the ENETC_RBMR_CM bit accordingly, so flow control survives ring
reconfiguration even when the link status does not change.
RBMR is now written as a whole word from enetc_enable_rxbdr() rather than
by read-modify-write from several call sites. Serialize the remaining RBMR
read-modify-write paths, the congestion mode update and the RX VLAN offload
update, with the new si->gen_lock so they cannot race each other.
Fixes: 5093406c78 ("net: enetc: implement ring reconfiguration procedure for PTP RX timestamping")
Signed-off-by: Wei Fang <wei.fang@nxp.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260821064140.1315611-2-wei.fang@oss.nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Hidayath Khan says:
====================
net/smc: fix use-after-free in smc_rx_pipe_buf_release()
smc_rx_pipe_buf_release() tests sk_state before taking the socket lock
and then dereferences conn->rmb_desc and conn->lgr. A concurrent close
runs smc_conn_free() in between, which releases those structures. On the
is_reg_err path smcr_buf_unuse() frees the descriptor outright, so this
is a use-after-free.
Patch 2/2 fixes this by taking the socket lock first and testing
conn->freed instead. smc_conn_free() sets that flag before releasing
anything, under the same lock, so the two paths exclude each other.
Patch 1/2 is a prerequisite. conn->freed shares a byte with killed and
out_of_sync as single-bit bitfields. out_of_sync is written from the
receive tasklet without the socket lock, so a concurrent store to freed
from process context can be lost in the read-modify-write. Patch 1/2
gives each flag its own byte so stores do not interfere.
====================
Link: https://patch.msgid.link/20260820074642.966856-1-hidayath@linux.ibm.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
