linux-stable.git/net, branch v6.18.32

vsock/virtio: fix accept queue count leak on transport mismatch

2026-05-17T15:15:37+00:00

commit 52bcb57a4e8a0865a76c587c2451906342ae1b2d upstream.

virtio_transport_recv_listen() calls sk_acceptq_added() before
vsock_assign_transport(). If vsock_assign_transport() fails or
selects a different transport, the error path returns without
calling sk_acceptq_removed(), permanently incrementing
sk_ack_backlog.

After approximately backlog+1 such failures, sk_acceptq_is_full()
returns true, causing the listener to reject all new connections.

Fix by moving sk_acceptq_added() to after the transport validation,
matching the pattern used by vmci_transport and hyperv_transport.

Fixes: c0cfa2d8a788 ("vsock: add multi-transports support")
Signed-off-by: Dudu Lu 
Reviewed-by: Bobby Eshleman 
Reviewed-by: Luigi Leonardi 
Reviewed-by: Stefano Garzarella 
Acked-by: Michael S. Tsirkin 
Link: https://patch.msgid.link/20260413131409.19022-1-phx0fer@gmail.com
Signed-off-by: Paolo Abeni 
Cc: Luigi Leonardi 
Signed-off-by: Greg Kroah-Hartman

vsock/virtio: fix empty payload in tap skb for non-linear buffers

2026-05-17T15:15:37+00:00

commit 3a3e3d90cbc79600544536723911657730759af3 upstream.

For non-linear skbs, virtio_transport_build_skb() goes through
virtio_transport_copy_nonlinear_skb() to copy the original payload
in the new skb to be delivered to the vsockmon tap device.
This manually initializes an iov_iter but does not set iov_iter.count.
Since the iov_iter is zero-initialized, the copy length is zero and no
payload is actually copied to the monitor interface, leaving data
un-initialized.

Fix this by removing the linear vs non-linear split and using
skb_copy_datagram_iter() with iov_iter_kvec() for all cases, as
vhost-vsock already does. This handles both linear and non-linear skbs,
properly initializes the iov_iter, and removes the now unused
virtio_transport_copy_nonlinear_skb().

While touching this code, let's also check the return value of
skb_copy_datagram_iter(), even though it's unlikely to fail.

Fixes: 4b0bf10eb077 ("vsock/virtio: non-linear skb handling for tap")
Reported-by: Yiqi Sun 
Signed-off-by: Stefano Garzarella 
Reviewed-by: Bobby Eshleman 
Reviewed-by: Arseniy Krasnov 
Link: https://patch.msgid.link/20260508164411.261440-3-sgarzare@redhat.com
Acked-by: Michael S. Tsirkin 
Signed-off-by: Paolo Abeni 
Cc: Luigi Leonardi 
Signed-off-by: Greg Kroah-Hartman

vsock/virtio: fix length and offset in tap skb for split packets

2026-05-17T15:15:37+00:00

commit 5f344d809e015fba3709e5219428c00b8ac5d7df upstream.

virtio_transport_build_skb() builds a new skb to be delivered to the
vsockmon tap device. To build the new skb, it uses the original skb
data length as payload length, but as the comment notes, the original
packet stored in the skb may have been split in multiple packets, so we
need to use the length in the header, which is correctly updated before
the packet is delivered to the tap, and the offset for the data.

This was also similar to what we did before commit 71dc9ec9ac7d
("virtio/vsock: replace virtio_vsock_pkt with sk_buff") where we probably
missed something during the skb conversion.

Also update the comment above, which was left stale by the skb
conversion and still mentioned a buffer pointer that no longer exists.

Fixes: 71dc9ec9ac7d ("virtio/vsock: replace virtio_vsock_pkt with sk_buff")
Signed-off-by: Stefano Garzarella 
Reviewed-by: Bobby Eshleman 
Reviewed-by: Arseniy Krasnov 
Link: https://patch.msgid.link/20260508164411.261440-2-sgarzare@redhat.com
Acked-by: Michael S. Tsirkin 
Signed-off-by: Paolo Abeni 
Cc: Luigi Leonardi 
Signed-off-by: Greg Kroah-Hartman

vsock: fix buffer size clamping order

2026-05-17T15:15:37+00:00

commit d114bfdc9b76bf93b881e195b7ec957c14227bab upstream.

In vsock_update_buffer_size(), the buffer size was being clamped to the
maximum first, and then to the minimum. If a user sets a minimum buffer
size larger than the maximum, the minimum check overrides the maximum
check, inverting the constraint.

This breaks the intended socket memory boundaries by allowing the
vsk->buffer_size to grow beyond the configured vsk->buffer_max_size.

Fix this by checking the minimum first, and then the maximum. This
ensures the buffer size never exceeds the buffer_max_size.

Fixes: b9f2b0ffde0c ("vsock: handle buffer_size sockopts in the core")
Suggested-by: Stefano Garzarella 
Signed-off-by: Norbert Szetei 
Reviewed-by: Stefano Garzarella 
Link: https://patch.msgid.link/180118C5-8BCF-4A63-A305-4EE53A34AB9C@doyensec.com
Signed-off-by: Jakub Kicinski 
Cc: Luigi Leonardi 
Signed-off-by: Greg Kroah-Hartman

batman-adv: tp_meter: fix tp_num leak on kmalloc failure

2026-05-17T15:15:37+00:00

commit ce425dd05d0fe7594930a0fb103634f35ac47bb6 upstream.

When batadv_tp_start() or batadv_tp_init_recv() fail to allocate a new
tp_vars object, the previously incremented bat_priv->tp_num counter is
never decremented. This causes tp_num to drift upward on each allocation
failure. Since only BATADV_TP_MAX_NUM sessions can be started and the count
is never reduced for these failed allocations, it causes to an exhaustion
of throughput meter sessions. In worst case, no new throughput meter
session can be started until the mesh interface is removed.

The error handling must decrement tp_num releasing the lock and aborting
the creation of an throughput meter session

Cc: stable@kernel.org
Fixes: 33a3bb4a3345 ("batman-adv: throughput meter implementation")
[ Context ]
Signed-off-by: Sven Eckelmann 
Signed-off-by: Greg Kroah-Hartman

Bluetooth: hci_conn: fix potential UAF in create_big_sync

2026-05-17T15:15:36+00:00

[ Upstream commit 0beddb0c380bed5f5b8e61ddbe14635bb73d0b41 ]

Add hci_conn_valid() check in create_big_sync() to detect stale
connections before proceeding with BIG creation. Handle the
resulting -ECANCELED in create_big_complete() and re-validate the
connection under hci_dev_lock() before dereferencing, matching the
pattern used by create_le_conn_complete() and create_pa_complete().

Keep the hci_conn object alive across the async boundary by taking
a reference via hci_conn_get() when queueing create_big_sync(), and
dropping it in the completion callback. The refcount and the lock
are complementary: the refcount keeps the object allocated, while
hci_dev_lock() serializes hci_conn_hash_del()'s list_del_rcu() on
hdev->conn_hash, as required by hci_conn_del().

hci_conn_put() is called outside hci_dev_unlock() so the final put
(which resolves to kfree() via bt_link_release) does not run under
hdev->lock, though the release path would be safe either way.

Without this, create_big_complete() would unconditionally
dereference the conn pointer on error, causing a use-after-free
via hci_connect_cfm() and hci_conn_del().

Fixes: eca0ae4aea66 ("Bluetooth: Add initial implementation of BIS connections")
Cc: stable@vger.kernel.org
Co-developed-by: Luiz Augusto von Dentz 
Signed-off-by: Luiz Augusto von Dentz 
Signed-off-by: David Carlier 
Signed-off-by: Luiz Augusto von Dentz 
[ kept stable's `qos->bcast.out.phy == 0x02` context line instead of upstream's renamed `qos->bcast.out.phys == BIT(1)` ]
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

batman-adv: bla: put backbone reference on failed claim hash insert

2026-05-17T15:15:34+00:00

commit ba9d20ee9076dac32c371116bacbe72480eb356c upstream.

When batadv_bla_add_claim() fails to insert a new claim into the hash, it
leaked a reference to the backbone_gw for which the claim was intended.
Call batadv_backbone_gw_put() on the error path to release the reference
and avoid leaking the backbone_gw object.

Cc: stable@kernel.org
Fixes: 3db0decf1185 ("batman-adv: Fix non-atomic bla_claim::backbone_gw access")
Signed-off-by: Sven Eckelmann 
Signed-off-by: Greg Kroah-Hartman

batman-adv: bla: only purge non-released claims

2026-05-17T15:15:34+00:00

commit cf6b604011591865ae39ac82de8978c1120d17af upstream.

When batadv_bla_purge_claims() goes through the list of claims, it is only
traversing the hash list with an rcu_read_lock(). Due to a potential
parallel batadv_claim_put(), it can happen that it encounters a claim which
was actually in the process of being released+freed by
batadv_claim_release(). In this case, backbone_gw is set to NULL before the
delayed RCU kfree is started. Calling batadv_bla_claim_get_backbone_gw() is
then no longer allowed because it would cause a NULL-ptr derefence.

To avoid this, only claims with a valid reference counter must be purged.
All others are already taken care of.

Cc: stable@kernel.org
Fixes: 23721387c409 ("batman-adv: add basic bridge loop avoidance code")
Signed-off-by: Sven Eckelmann 
Signed-off-by: Greg Kroah-Hartman

batman-adv: bla: prevent use-after-free when deleting claims

2026-05-17T15:15:34+00:00

commit 4ae1709a314060a196981b344610d023ea841e57 upstream.

When batadv_bla_del_backbone_claims() removes all claims for a backbone, it
does this by dropping the link entry in the hash list. This list entry
itself was one of the references which need to be dropped at the same time
via batadv_claim_put().

But the batadv_claim_put() must not be done before the last access to the
claim object in this function. Otherwise the claim might be freed already
by the batadv_claim_release() function before the list entry was dropped.

Cc: stable@kernel.org
Fixes: 23721387c409 ("batman-adv: add basic bridge loop avoidance code")
Signed-off-by: Sven Eckelmann 
Signed-off-by: Greg Kroah-Hartman

batman-adv: stop caching unowned originator pointers in BAT IV

2026-05-17T15:15:34+00:00

commit f03e8583532941b07761c5429de7d50766fa3110 upstream.

BAT IV keeps the last-hop neighbor address in each neigh_node, but some
paths also cache an originator pointer derived from a temporary lookup.
That pointer is not owned by the neigh_node and may no longer refer to a
live originator entry after purge handling runs.

Stop storing the auxiliary originator pointer in the BAT IV neighbor
state. When BAT IV needs the neighbor originator data, resolve it from
the stored neighbor address and drop the reference again after use.

Fixes: c6c8fea29769 ("net: Add batman-adv meshing protocol")
Cc: stable@kernel.org
Reported-by: Yuan Tan 
Reported-by: Yifan Wu 
Reported-by: Juefei Pu 
Reported-by: Xin Liu 
Signed-off-by: Jiexun Wang 
Signed-off-by: Ren Wei 
[sven: avoid bonding logic for outgoing OGM]
Signed-off-by: Sven Eckelmann 
Signed-off-by: Greg Kroah-Hartman