linux.git/net/core, branch v7.2 Linux kernel source tree Merge tag 'net-7.2-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2026-08-13T15:37:26+00:00 Linus Torvalds torvalds@linux-foundation.org 2026-08-13T15:37:26+00:00 e14aacefb78d942d2308d9821fe52d75d21a824e Pull networking fixes from Paolo Abeni: "Including fixes from netfilter. There is a known WiFi/mt76 regression, waiting for a complete fix that should land soonish. Previous releases - regressions: - tcp: fix icsk_ack.ato bitfield overflow - af_unix: Unlink scc_entry in unix_del_edge() - ipv4: fix use-after-free in fib_nhc_update_mtu() - netfilter: - ipset: fix refcount race between list:set GC and swap - nf_tables_offload: suppress WARN_ON_ONCE for ENOMEM in abort path - sched: act_ct: fix sk_buff leak when the header checks reject a packet - sctp: clear new_transport when removing a peer - dibs: correct freeing of dmb_clientid_arr - ovpn: fix NULL dereference when killing missing key - eth: - veth: fix queue index used to wake the peer txq in veth_poll - ngbe: fix NULL pointer dereference in non-MSI-X interrupt enabling - gve: fix zero-length skb frag with header-split Previous releases - always broken: - core: fix skb length accounting after generic XDP frag adjustment - af_packet: don't send zero-byte data in tpacket_snd(). - eth: - bnxt: avoid deadlock when canceling IRQ affinity notifier - ipvlan: inherit needed_headroom and needed_tailroom from phy_dev" * tag 'net-7.2-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (55 commits) l2tp: fix tunnel and session refcount leak on seq_file release net/sched: cls_bpf: reject dev-bound programs bound to a different device sctp: fix use-after-free of cached ASCONF chunk net: ethernet: ti: am65-cpsw-nuss: Fix port_id extraction from SRC TAG sctp: clear new_transport when removing a peer net/dibs: Correct freeing of dmb_clientid_arr net/sched: cls_u32: skip hash tables in u32_bind_class() gve: fix NULL dereference due to missing ptp adjfine gve: fix zero-length skb frag with header-split net/sched: act_api: fix TOCTOU NULL deref on a->goto_chain af_packet: Don't send zero-byte data in tpacket_snd(). tipc: read le->link under the node lock in tipc_node_link_down() selftests: tls: cover splice after a failed decrypt net/tls: Fail tls_sw_splice_read() after a failed async decrypt net: ngbe: fix NULL pointer dereference in non-MSI-X interrupt enabling net: tap: fix wrong transport_header when sending VLAN-tagged frame net: packet: fix wrong transport_header when sending VLAN-tagged frame vxlan: do not arm the ageing timer on a device that is down ipv4: fix use-after-free in fib_nhc_update_mtu() NTB: ntb_netdev: Preserve RX queue depth on allocation failure ... 
Pull networking fixes from Paolo Abeni:
 "Including fixes from netfilter.

  There is a known WiFi/mt76 regression, waiting for a complete fix that
  should land soonish.

  Previous releases - regressions:

   - tcp: fix icsk_ack.ato bitfield overflow

   - af_unix: Unlink scc_entry in unix_del_edge()

   - ipv4: fix use-after-free in fib_nhc_update_mtu()

   - netfilter:
      - ipset: fix refcount race between list:set GC and swap
      - nf_tables_offload: suppress WARN_ON_ONCE for ENOMEM in abort
        path

   - sched: act_ct: fix sk_buff leak when the header checks reject a
     packet

   - sctp: clear new_transport when removing a peer

   - dibs: correct freeing of dmb_clientid_arr

   - ovpn: fix NULL dereference when killing missing key

   - eth:
      - veth: fix queue index used to wake the peer txq in veth_poll
      - ngbe: fix NULL pointer dereference in non-MSI-X interrupt
        enabling
      - gve: fix zero-length skb frag with header-split

  Previous releases - always broken:

   - core: fix skb length accounting after generic XDP frag adjustment

   - af_packet: don't send zero-byte data in tpacket_snd().

   - eth:
      - bnxt: avoid deadlock when canceling IRQ affinity notifier
      - ipvlan: inherit needed_headroom and needed_tailroom from
        phy_dev"

* tag 'net-7.2-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (55 commits)
  l2tp: fix tunnel and session refcount leak on seq_file release
  net/sched: cls_bpf: reject dev-bound programs bound to a different device
  sctp: fix use-after-free of cached ASCONF chunk
  net: ethernet: ti: am65-cpsw-nuss: Fix port_id extraction from SRC TAG
  sctp: clear new_transport when removing a peer
  net/dibs: Correct freeing of dmb_clientid_arr
  net/sched: cls_u32: skip hash tables in u32_bind_class()
  gve: fix NULL dereference due to missing ptp adjfine
  gve: fix zero-length skb frag with header-split
  net/sched: act_api: fix TOCTOU NULL deref on a->goto_chain
  af_packet: Don't send zero-byte data in tpacket_snd().
  tipc: read le->link under the node lock in tipc_node_link_down()
  selftests: tls: cover splice after a failed decrypt
  net/tls: Fail tls_sw_splice_read() after a failed async decrypt
  net: ngbe: fix NULL pointer dereference in non-MSI-X interrupt enabling
  net: tap: fix wrong transport_header when sending VLAN-tagged frame
  net: packet: fix wrong transport_header when sending VLAN-tagged frame
  vxlan: do not arm the ageing timer on a device that is down
  ipv4: fix use-after-free in fib_nhc_update_mtu()
  NTB: ntb_netdev: Preserve RX queue depth on allocation failure
  ...
net: expect instance lock in netdev_queue_get_dma_dev() 2026-08-10T22:54:42+00:00 Jakub Kicinski kuba@kernel.org 2026-08-06T22:56:26+00:00 92465f46f3c3a92e4758af20d2363b7adc43e1f5 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: b6c5f9454ef34 ("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> 
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: b6c5f9454ef34 ("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>
net: fix skb length accounting after generic XDP frag adjustment 2026-08-08T00:01:05+00:00 Sun Jian sun.jian.kdev@gmail.com 2026-08-04T05:40:38+00:00 33f2b2eb33d666ecac68031e0f31424fb70528db 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: e6d5dbdd20aa ("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> 
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: e6d5dbdd20aa ("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>
Merge tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf 2026-08-07T15:08:57+00:00 Linus Torvalds torvalds@linux-foundation.org 2026-08-07T15:08:57+00:00 a13307e97d5c54b65720bb71fa379960ded1e51a Pull BPF fixes from Daniel Borkmann: - Fix BPF verifier to preserve full pointer state for commuted scalar += pointer arithmetic (Yiyang Chen, Eduard Zingerman) - Fix a use-after-free of request sockets in the BPF TCP iterator batching (Jose Fernandez) - Fix a use-after-free of sk_redir in the BPF sockmap send verdict path (Chengfeng Ye) - Fix a netns reference imbalance in the BPF conntrack kfuncs (Chengfeng Ye) - Fix bpf_get_fsverity_digest() dynptr assumptions and silent digest truncation (Eric Biggers) - Fix bpf_tcp_{gen,check}_syncookie to check sk_state before sk_protocol to make sure it is a full socket (Luxiao Xu) - Fix rqspinlock to reset the tail when preserving the queue on deadlock (Kumar Kartikeya Dwivedi) * tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf: rqspinlock: Reset tail when preserving queue on deadlock bpf: Check sk_state before sk_protocol in bpf_tcp_*_syncookie fsverity: Fix silent truncation in bpf_get_fsverity_digest() fsverity: Fix bpf_get_fsverity_digest() dynptr assumptions bpf: tcp: Fix use-after-free in bpf_iter_tcp_established_batch() bpf: Fix netns reference imbalance in conntrack kfuncs bpf, sockmap: Fix sk_redir use-after-free in send verdict selftests/bpf: Cover commuted pointer state propagation bpf: Propagate untrusted pointer state in commuted arithmetic bpf: Preserve pointer state for commuted arithmetic bpf: Simplify sanitize_err() signature 
Pull BPF fixes from Daniel Borkmann:

 - Fix BPF verifier to preserve full pointer state for commuted
   scalar += pointer arithmetic (Yiyang Chen, Eduard Zingerman)

 - Fix a use-after-free of request sockets in the BPF TCP iterator
   batching (Jose Fernandez)

 - Fix a use-after-free of sk_redir in the BPF sockmap send verdict
   path (Chengfeng Ye)

 - Fix a netns reference imbalance in the BPF conntrack kfuncs
   (Chengfeng Ye)

 - Fix bpf_get_fsverity_digest() dynptr assumptions and silent
   digest truncation (Eric Biggers)

 - Fix bpf_tcp_{gen,check}_syncookie to check sk_state before
   sk_protocol to make sure it is a full socket (Luxiao Xu)

 - Fix rqspinlock to reset the tail when preserving the queue
   on deadlock (Kumar Kartikeya Dwivedi)

* tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
  rqspinlock: Reset tail when preserving queue on deadlock
  bpf: Check sk_state before sk_protocol in bpf_tcp_*_syncookie
  fsverity: Fix silent truncation in bpf_get_fsverity_digest()
  fsverity: Fix bpf_get_fsverity_digest() dynptr assumptions
  bpf: tcp: Fix use-after-free in bpf_iter_tcp_established_batch()
  bpf: Fix netns reference imbalance in conntrack kfuncs
  bpf, sockmap: Fix sk_redir use-after-free in send verdict
  selftests/bpf: Cover commuted pointer state propagation
  bpf: Propagate untrusted pointer state in commuted arithmetic
  bpf: Preserve pointer state for commuted arithmetic
  bpf: Simplify sanitize_err() signature
net: avoid theoretical races with ref drain 2026-08-06T16:37:03+00:00 Jakub Kicinski kuba@kernel.org 2026-08-06T02:28:21+00:00 d31c14e56a4f01f0689c29c0bcbcd45f65b4a473 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: 12c765be84d2 ("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> 
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: 12c765be84d2 ("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>
net: Defer netdev KOBJ_ADD uevent until the device is published 2026-08-06T16:36:18+00:00 Dragos Tatulea dtatulea@nvidia.com 2026-08-06T08:07:58+00:00 8e63c9e6179ace3033dcd19991f95386e9d3130f 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: f994752b1127 ("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> 
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: f994752b1127 ("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>
xdp: reject clones that overrun skb_shared_info tailroom 2026-08-06T15:49:19+00:00 Zhiling Zou zhilinz@nebusec.ai 2026-08-03T12:15:32+00:00 e48e8edbef2eb824201495daa5234560f632b23c 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: e624d4ed4aa8 ("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> 
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: e624d4ed4aa8 ("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>
net: remove WARN_ON_ONCE() from sk_mc_loop() 2026-08-06T11:10:16+00:00 Eric Dumazet edumazet@google.com 2026-08-04T15:20:48+00:00 b8a39a09ae4eaae04309e1e38ed6a1101d967496 sk_mc_loop() can be called for sockets that are neither AF_INET nor AF_INET6 (e.g. AF_PACKET sockets when sending packets via raw/packet socket over virtual devices such as VRF or ipvlan). In such cases, sk_family is not AF_INET/AF_INET6 and sk_mc_loop() falls through the switch statement and triggers WARN_ON_ONCE(1). Non-INET sockets do not support IP_MULTICAST_LOOP or IPV6_MULTICAST_LOOP options, so loopback should default to true without generating a warning. Fixes: f60e5990d9c1 ("ipv6: protect skb->sk accesses from recursive dereference inside the stack") Reported-by: syzbot+22c3218a6fa219e47321@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/6a72024c.13623e66.bdc14.0019.GAE@google.com/T/#u Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20260804152048.2134341-1-edumazet@google.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> 
sk_mc_loop() can be called for sockets that are neither AF_INET
nor AF_INET6 (e.g. AF_PACKET sockets when sending packets via raw/packet
socket over virtual devices such as VRF or ipvlan).

In such cases, sk_family is not AF_INET/AF_INET6 and sk_mc_loop() falls
through the switch statement and triggers WARN_ON_ONCE(1).

Non-INET sockets do not support IP_MULTICAST_LOOP or IPV6_MULTICAST_LOOP
options, so loopback should default to true without generating a warning.

Fixes: f60e5990d9c1 ("ipv6: protect skb->sk accesses from recursive dereference inside the stack")
Reported-by: syzbot+22c3218a6fa219e47321@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/6a72024c.13623e66.bdc14.0019.GAE@google.com/T/#u
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260804152048.2134341-1-edumazet@google.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
bpf: Check sk_state before sk_protocol in bpf_tcp_*_syncookie 2026-08-05T20:24:27+00:00 Luxiao Xu rakukuip@gmail.com 2026-08-04T14:29:01+00:00 31a420a822ff92e2090bd5d65efe8e34e2d6d9b8 bpf_tcp_gen_syncookie and bpf_tcp_check_syncookie accept a socket pointer 'sk' with argument type ARG_PTR_TO_BTF_ID_SOCK_COMMON. However, they access sk->sk_protocol without validating whether 'sk' represents a full socket. Fix this issue by checking sk->sk_state != TCP_LISTEN before inspecting sk->sk_protocol in both bpf_tcp_gen_syncookie and bpf_tcp_check_syncookie. Since mini-sockets are never in the TCP_LISTEN state, the condition short-circuits and prevents dereferencing fullsock-specific fields. Fixes: 399040847084 ("bpf: add helper to check for a valid SYN cookie") Fixes: 70d66244317e ("bpf: add bpf_tcp_gen_syncookie helper") Reported-by: Vega <vega@nebusec.ai> Signed-off-by: Luxiao Xu <rakukuip@gmail.com> Signed-off-by: Ren Wei <enjou1224z@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://lore.kernel.org/bpf/6218aa3534d0d2d3f448fde70a8dc2769d7a8201.1785823138.git.rakukuip@gmail.com 
bpf_tcp_gen_syncookie and bpf_tcp_check_syncookie accept a socket pointer
'sk' with argument type ARG_PTR_TO_BTF_ID_SOCK_COMMON. However, they access
sk->sk_protocol without validating whether 'sk' represents a full socket.

Fix this issue by checking sk->sk_state != TCP_LISTEN before inspecting
sk->sk_protocol in both bpf_tcp_gen_syncookie and bpf_tcp_check_syncookie.
Since mini-sockets are never in the TCP_LISTEN state, the condition
short-circuits and prevents dereferencing fullsock-specific fields.

Fixes: 399040847084 ("bpf: add helper to check for a valid SYN cookie")
Fixes: 70d66244317e ("bpf: add bpf_tcp_gen_syncookie helper")
Reported-by: Vega <vega@nebusec.ai>
Signed-off-by: Luxiao Xu <rakukuip@gmail.com>
Signed-off-by: Ren Wei <enjou1224z@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://lore.kernel.org/bpf/6218aa3534d0d2d3f448fde70a8dc2769d7a8201.1785823138.git.rakukuip@gmail.com
net: devmem: prevent net-iov / page mixing 2026-07-30T23:27:03+00:00 Pavel Begunkov asml.silence@gmail.com 2026-07-27T11:19:37+00:00 53a43508ee332d8bffe40590c3d189c92a551f9f We should either have net_iov or page backed frags in a single skb, otherwise it blows up down the stack. Don't allow mixing in zerocopy_fill_skb_from_devmem(). Fixes: bd61848900bff ("net: devmem: Implement TX path") Cc: stable@vger.kernel.org Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Acked-by: Stanislav Fomichev <sdf@fomichev.me> Reviewed-by: Mina Almasry <almasrymina@google.com> Reviewed-by: Bobby Eshleman <bobbyeshleman@meta.com> Link: https://patch.msgid.link/e3199788c4732545627a4721097ebb71ad737bab.1785150502.git.asml.silence@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
We should either have net_iov or page backed frags in a single skb,
otherwise it blows up down the stack. Don't allow mixing in
zerocopy_fill_skb_from_devmem().

Fixes: bd61848900bff ("net: devmem: Implement TX path")
Cc: stable@vger.kernel.org
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Reviewed-by: Mina Almasry <almasrymina@google.com>
Reviewed-by: Bobby Eshleman <bobbyeshleman@meta.com>
Link: https://patch.msgid.link/e3199788c4732545627a4721097ebb71ad737bab.1785150502.git.asml.silence@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>