linux.git/net/vmw_vsock, branch v7.3-rc2

vsock/vmci: validate packet source for connected sockets

2026-08-31T23:50:54+00:00

vmci_transport_recv_stream_cb() looks up sockets first by the full source
and destination tuple, then by destination only in the bound table. The
fallback can select a non-listening socket without checking whether the
packet came from its stored peer.

This was reproduced with two VMCI contexts. A RST from the context not
stored in a TCP_SYN_SENT socket reset that socket after it was selected by
the destination-only lookup.

VMCI can process notification packets in bottom-half context when the
socket is not owned by user context, or defer packets to a workqueue. Use
vsock_check_source() after taking the socket lock in the bottom-half path,
and recheck after lock_sock() in the workqueue path. Listening sockets
continue to accept packets from any source.

Reply with a RST addressed from the received packet before dropping a
source that fails validation. This preserves the existing reset behavior
for bound non-listening and concurrently closed sockets without directing
the reset to a connected socket's stored peer.

Fixes: d021c344051a ("VSOCK: Introduce VM Sockets")
Reported-by: Sashiko 
Closes: https://lore.kernel.org/netdev/20260814121255.6B5001F000E9@smtp.kernel.org/
Cc: stable@vger.kernel.org
Suggested-by: Stefano Garzarella 
Suggested-by: Paolo Abeni 
Signed-off-by: Daehyeon Ko <4ncienth@gmail.com>
Reviewed-by: Vishnu Dasa 
Link: https://patch.msgid.link/20260826003929.966160-3-4ncienth@gmail.com
Signed-off-by: Jakub Kicinski

vsock/virtio: validate packet source for connected sockets

2026-08-31T23:50:54+00:00

virtio_transport_recv_pkt() looks up sockets first by the full source and
destination tuple, then by destination only in the bound table. The
fallback is needed for listening and connecting sockets, but sockets remain
in the bound table after connect(), so it can also return a non-listening
socket.

The fallback does not validate the source address. In TCP_SYN_SENT, a
RESPONSE from an unrelated source can transition the victim socket to
TCP_ESTABLISHED while its stored remote address remains unchanged.
Subsequent RW packets from that source are delivered through the same
destination-only fallback.

This was reproduced with capability-empty processes under different UIDs.
The attacker discovered the target tuple through unprivileged AF_VSOCK
sock_diag and caused the victim socket to read 16 attacker-chosen bytes;
the intended peer-side socket read 0 of those 16 bytes.

Add vsock_check_source() to validate the transport, source port and source
CID against the peer stored in a non-listening socket. The local transport
is the CID exception because its packets are generated internally with
VMADDR_CID_LOCAL as their source, including connections using CID aliases.

Use the helper after lock_sock() in the virtio receive path.

Fixes: 06a8fc78367d ("VSOCK: Introduce virtio_vsock_common.ko")
Closes: https://lore.kernel.org/netdev/20260813121236.2328599-1-4ncienth@gmail.com/
Cc: stable@vger.kernel.org
Suggested-by: Stefano Garzarella 
Reviewed-by: Bobby Eshleman 
Signed-off-by: Daehyeon Ko <4ncienth@gmail.com>
Link: https://patch.msgid.link/20260826003929.966160-2-4ncienth@gmail.com
Signed-off-by: Jakub Kicinski

Merge tag 'net-7.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2026-08-27T20:53:43+00:00

Pull networking fixes from Jakub Kicinski:
 "Including fixes from Bluetooth, IPSec and Netfilter.

  Current release - fix to a fix:

   - netfilter: ipset: remove need to allocate memory on delete operations

  Current release - regressions:

   - macb: drop CONFIG_OF #if block, fix build

  Previous releases - always broken:

   - stream of fixes for SCTP continues

   - inet: frags: strip GSO state from fragments before reassembly

   - virtio-net: ensure that TCP packets don't overflow gso_segs

   - tcp-ao: fix use-after-free of current_key on reconnect to another
     peer

   - page_pool: remove zone/policy GFP flags when allocating XArray
     entries

   - Bluetooth: L2CAP: reject accept queue add unless BT_LISTEN

   - tls: device: fix out-of-bounds write in tls_append_frag()

   - eth: bnxt:
      - ring the doorbell when SW USO exits early, avoid packets stuck
        in Tx
      - gate TPH enablement behind BNXT_SUPPORTS_QUEUE_API check, avoid
        users of older NICs seeing non-actionable warning messages

   - eth: qede: fix NULL pointer dereference in TPA fragment processing"

* tag 'net-7.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (216 commits)
  inet: frags: strip GSO state from fragments before reassembly
  net/sched: sch_htb: limit htb_classify inner-class filter hops
  selftests/net: packetdrill: add tcp_urg_ptr_retransmit
  tcp: fix corruption of urgent data on multi-segment retransmit
  usb: atm: usbatm: fix invalid ci_range initialization
  net: fec: only stop PTP if it was initialized
  slip: remove slip_hangup() to fix use-after-free in slip_receive_buf()
  net: bridge: mcast: fix use-after-free of a master VLAN's multicast context
  net/sched: bound qdisc_pkt_len to prevent qdisc soft lockup
  net: dsa: mxl862xx: enable assisted learning on CPU port
  net: stmmac: restore NET_IP_ALIGN in the RX DMA offset
  net: stmmac: drop gso_enabled_types and rely on netdev features
  net: stmmac: selftests: Don't test flow control for small rx fifos
  net: stmmac: selftests: Account for the UC filter list for filtering tests
  net: stmmac: dwxgmac: Account for the primary MAC address for UC filtering
  net: stmmac: dwmac4: Account for the primary MAC address for UC filtering
  net: stmmac: dwmac1000: Account for the primary MAC address for UC filtering
  net: stmmac: selftests: Check multiple MMC counters
  selftests: net: Fix slow configurations in big_tcp_tunnels.sh
  selftests: net: Lower threshold with csum offload off in big_tcp_tunnels.sh
  ...

Merge tag 'hyperv-next-signed-20260826' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux

2026-08-26T23:47:40+00:00

Pull hyperv updates from Wei Liu:

 - Decrypt netvsc buffer on contiguous direct-map addresses (Kameron
   Carr)

 - Drop WS2012/2012R2 & Win8/8.1 Hyper-V support (Michael Kelley)

 - Use more meaningful errnos for hypercall status code (Hardik Garg)

 - Fix lost interrupts on CPU hot-unplug for Hyper-V PCI/MSI (Naman
   Jain)

 - Reserve more MSHV vectors for Linux root partition (Wei Liu)

* tag 'hyperv-next-signed-20260826' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux:
  clocksource: hyper-v: Remove support for stimer interrupts in message mode
  scsi: storvsc: Remove support for storvsc protocol of old Hyper-V hosts
  hv_netvsc: Remove GPADL teardown special case for old Hyper-V hosts
  hv_sock: Remove check for old Hyper-V hosts
  Drivers: hv: Remove support for WS2012/2012R2 & Win8/8.1 version of Hyper-V
  hv_netvsc: Allocate send/receive buffers using vmbus_alloc_buffer()
  Drivers: hv: vmbus: Add vmbus_alloc_buffer()/vmbus_free_buffer() for CoCo VMs
  Drivers: hv: vmbus: add vmbus_establish_gpadl_caller_decrypted()
  Drivers: hv: vmbus: Skip VMBus module cleanup for non-nested root partition
  x86/hyperv: reserve more vectors
  PCI: hv: Set irq_retrigger callback for the Hyper-V PCI MSI irqchip
  Drivers: hv: Use meaningful errnos for hypercall status codes

vsock/virtio: flush works in dependency order

2026-08-25T10:35:51+00:00

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: 0ea9e1d3a9e3 ("VSOCK: Introduce virtio_transport.ko")
Cc: stable@vger.kernel.org
Signed-off-by: Chengfeng Ye 
Link: https://patch.msgid.link/20260822164556.3750959-1-nicoyip.dev@gmail.com
Signed-off-by: Paolo Abeni

hv_sock: Remove check for old Hyper-V hosts

2026-08-24T00:35:42+00:00

With the overall removal of Linux support for running on Hyper-V
hosts earlier than WS2016 and Windows 10, the check for such versions
during hv_sock initialization is no longer necessary. Remove the
check.

Signed-off-by: Michael Kelley 
Signed-off-by: Wei Liu

Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

2026-08-21T00:07:50+00:00

Pull vhost,vdpa,virtio updates from Michael Tsirkin:

 - transport v3 support in virtio-mmio

 - suspend support in vduse

 - fixes, cleanups all over the place

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (54 commits)
  vduse: Add suspend
  vduse: do not take rwsem at reset work flush
  vduse: add F_QUEUE_READY feature
  vduse: add VDUSE_SET_FEATURES ioctl
  vduse: add VDUSE_GET_FEATURES ioctl
  vduse: store control device pointer
  tools/virtio: Fix control typo in trace agent comment
  tools/virtio: Fix userspace typo in vringh test comment
  vhost: reject zero-size IOTLB INVALIDATE
  vdpa: Remove redundant dev_err()
  virtio_ring: fix infinite loop in virtnet_poll_cleantx when device is broken
  vdpa/mlx5: roll back MR update after VQ setup failure
  MAINTAINERS: remove Gabriel from LiteX and fw-cfg drivers
  virtio_mem: fix typo in comment
  vdpa/solidrun: fix typos in snet_ctrl comments
  virtio: fix article before virtio in dma-buf comment
  vhost: fix inaccurate kdoc in iotlb helpers
  virtio: rtc: time out alarm requests
  vdpa/mlx5: fix wrong MLX5_ADDR_OF struct type in alloc_inout()
  vdpa: octeon_ep: add missing MODULE_DEVICE_TABLE()
  ...

vsock/virtio: restore msg_iter on transmission failure

2026-08-19T10:38:44+00:00

When transmission fails in virtio_transport_send_pkt_info, the msg_iter
might have been partially advanced. If we don't restore it, the next
attempt to send data will use an incorrect iterator state, leading to
desync and warnings like "send_pkt() returns 0, but X expected".

Specifically, this can happen in the following scenario, triggered by
the syzkaller repro:

1. A write-only VMA (PROT_WRITE only) is partially populated by a
   prior TUN write that failed with -EIO but still faulted in some
   pages).
2. A vsock sendmmsg call with MSG_ZEROCOPY requests transmission of a
   buffer from this VMA.
3. The first packet (64KB) is sent successfully because the pages are
   populated.
4. The second packet allocation fails because GUP fast pins the first page
   but GUP slow fails on the next unpopulated page due to PROT_WRITE-only
   permissions.
5. The iterator is advanced by the partially successful GUP (68KB total
   advanced: 64KB from first packet + 4KB from second), but the send loop
   breaks and only reports 64KB sent. This creates a 4KB desync.
6. The next retry starts with a non-zero iov_offset, disabling zerocopy
   and falling back to copy mode.
7. In copy mode, the transmission succeeds for the next packets but
   exhausts the iterator early because of the desync.
8. The final retry sees an empty iterator but zerocopy is re-enabled
   (offset resets). It attempts to send the remaining bytes with zerocopy
   but pins 0 pages, creating an empty packet.
9. The transport sends the empty packet, triggering the warning because
   the returned bytes (header only) do not match the expected payload size.
10. The loop continues to spin, allocating ubuf_info each time, eventually
    exhausting sysctl_optmem_max and returning -ENOMEM to userspace.

Restore msg_iter to its original state before the packet allocation
and transmission attempt if they fail.

Fixes: e0718bd82e27 ("vsock: enable setting SO_ZEROCOPY")
Reported-by: syzbot+28e5f3d207b14bae122a@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=28e5f3d207b14bae122a
Assisted-by: gemini:gemini-3.1-pro
Reviewed-by: Stefano Garzarella 
Signed-off-by: Octavian Purdila 
Message-ID: <20260622222757.2130402-3-tavip@google.com>
Signed-off-by: Michael S. Tsirkin

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2026-08-18T17:42:41+00:00

Merge in late fixes in preparation for the net-next PR.

Conflicts:

drivers/dpll/dpll_core.c
drivers/dpll/dpll_netlink.c
  33f016b23a219 ("dpll: fix NULL deref in dpll_device_ops() during teardown race")
  b1d0c412088e3 ("dpll: add STATE_CONNECTED_OVERRIDE pin capability")
https://lore.kernel.org/aoR9YYY2P5--3x0N@sirena.org.uk
https://lore.kernel.org/aoR9VmKllVGwmQn_@sirena.org.uk

No adjacent changes.

Signed-off-by: Jakub Kicinski

vsock: use sock_error() to consume sk_err after a failed connect

2026-08-18T12:58:53+00:00

vsock_connect() returns sk_err to userspace but does not clear it:
  if (sk->sk_err) {
            err = -sk->sk_err;

For a blocking connect() the error has already been delivered as
connect()'s return value, so leaving it set causes subsequent operations
like poll()/epoll() to keep reporting POLLERR even though the connect
failure was already delivered.

The error should be consumed once it has been returned to userspace.
Switch to sock_error(), which reads and clears sk_err atomically,
matching the behavior of other protocol implementations such as
__inet_stream_connect().

Fixes: d021c344051a ("VSOCK: Introduce VM Sockets")
Tested-by: Wupeng Ma 
Reviewed-by: Stefano Garzarella 
Signed-off-by: Nguyen Dinh Phi 
Link: https://patch.msgid.link/20260813173024.2362935-4-phind.uet@gmail.com
Signed-off-by: Paolo Abeni