vsock/vmci: convert VMCI error code to -ENOMEM on receive

This adds conversion of VMCI specific error code to general -ENOMEM. It
is preparation for the next patch, which changes af_vsock.c behaviour
on receive to pass value returned from transport to the user.

Signed-off-by: Arseniy Krasnov <AVKrasnov@sberdevices.ru>
Reviewed-by: Vishnu Dasa <vdasa@vmware.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

vsock/vmci: convert VMCI error code to -ENOMEM on send

This adds conversion of VMCI specific error code to general -ENOMEM. It
is needed, because af_vsock.c passes error value returned from transport
to the user, which does not expect to get VMCI_ERROR_* values.

Fixes: c43170b7e157 ("vsock: return errors other than -ENOMEM to socket")
Signed-off-by: Arseniy Krasnov <AVKrasnov@sberdevices.ru>
Reviewed-by: Vishnu Dasa <vdasa@vmware.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: vmw_vsock: vmci: Check memcpy_from_msg()

vmci_transport_dgram_enqueue() does not check the return value
of memcpy_from_msg(). If memcpy_from_msg() fails, it is possible that
uninitialized memory contents are sent unintentionally instead of user's
message in the datagram to the destination. Return with an error if
memcpy_from_msg() fails.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: 0f7db23a07af ("vmci_transport: switch ->enqeue_dgram, ->enqueue_stream and ->dequeue_stream to msghdr")
Signed-off-by: Artem Chernyshev <artem.chernyshev@red-soft.ru>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Vishnu Dasa <vdasa@vmware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

vsock/vmci: fix repeated words in comments

Delete the redundant word 'that'.

Signed-off-by: Jilin Yuan <yuanjilin@cdjrlc.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: remove noblock parameter from skb_recv_datagram()

skb_recv_datagram() has two parameters 'flags' and 'noblock' that are
merged inside skb_recv_datagram() by 'flags | (noblock ? MSG_DONTWAIT : 0)'

As 'flags' may contain MSG_DONTWAIT as value most callers split the 'flags'
into 'flags' and 'noblock' with finally obsolete bit operations like this:

skb_recv_datagram(sk, flags & ~MSG_DONTWAIT, flags & MSG_DONTWAIT, &rc);

And this is not even done consistently with the 'flags' parameter.

This patch removes the obsolete and costly splitting into two parameters
and only performs bit operations when really needed on the caller side.

One missing conversion thankfully reported by kernel test robot. I missed
to enable kunit tests to build the mctp code.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

vsock: each transport cycles only on its own sockets

When iterating over sockets using vsock_for_each_connected_socket, make
sure that a transport filters out sockets that don't belong to the
transport.

There actually was an issue caused by this; in a nested VM
configuration, destroying the nested VM (which often involves the
closing of /dev/vhost-vsock if there was h2g connections to the nested
VM) kills not only the h2g connections, but also all existing g2h
connections to the (outmost) host which are totally unrelated.

Tested: Executed the following steps on Cuttlefish (Android running on a
VM) [1]: (1) Enter into an `adb shell` session - to have a g2h
connection inside the VM, (2) open and then close /dev/vhost-vsock by
`exec 3< /dev/vhost-vsock && exec 3<&-`, (3) observe that the adb
session is not reset.

[1] https://android.googlesource.com/device/google/cuttlefish/

Fixes: c0cfa2d8a788 ("vsock: add multi-transports support")
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jiyong Park <jiyong@google.com>
Link: https://lore.kernel.org/r/20220311020017.1509316-1-jiyong@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: sock: introduce sk_error_report

This patch introduces a function wrapper to call the sk_error_report
callback. That will prepare to add additional handling whenever
sk_error_report is called, for example to trace socket errors.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

vsock/vmci: remove the repeated word "be"

Remove the repeated word "be".

Signed-off-by: gushengxian <gushengxian@yulong.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

vsock/vmci: Remove redundant assignment to err

Variable 'err' is set to zero but this value is never read as it is
overwritten with a new value later on, hence it is a redundant
assignment and can be removed.

Clean up the following clang-analyzer warning:

net/vmw_vsock/vmci_transport.c:948:2: warning: Value stored to 'err' is
never read [clang-analyzer-deadcode.DeadStores]

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

vsock/vmci: log once the failed queue pair allocation

VMCI feature is not supported in conjunction with the vSphere Fault
Tolerance (FT) feature.

VMware Tools can repeatedly try to create a vsock connection. If FT is
enabled the kernel logs is flooded with the following messages:

qp_alloc_hypercall result = -20
Could not attach to queue pair with -20

"qp_alloc_hypercall result = -20" was hidden by commit e8266c4c3307
("VMCI: Stop log spew when qp allocation isn't possible"), but "Could
not attach to queue pair with -20" is still there flooding the log.

Since the error message can be useful in some cases, print it only once.

Fixes: d021c344051a ("VSOCK: Introduce VM Sockets")
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Jorgen Hansen <jhansen@vmware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

vsock/vmci: make vmci_vsock_transport_cb() static

Fix the following gcc-9.3 warning when building with 'make W=1':
net/vmw_vsock/vmci_transport.c:2058:6: warning: no previous prototype
for ‘vmci_vsock_transport_cb’ [-Wmissing-prototypes]
2058 | void vmci_vsock_transport_cb(bool is_host)
| ^~~~~~~~~~~~~~~~~~~~~~~

Fixes: b1bba80a4376 ("vsock/vmci: register vmci_transport only when VMCI guest/host are active")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

vsock: add VMADDR_CID_LOCAL definition

The VMADDR_CID_RESERVED (1) was used by VMCI, but now it is not
used anymore, so we can reuse it for local communication
(loopback) adding the new well-know CID: VMADDR_CID_LOCAL.

Cc: Jorgen Hansen <jhansen@vmware.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Jorgen Hansen <jhansen@vmware.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

vsock: prevent transport modules unloading

This patch adds 'module' member in the 'struct vsock_transport'
in order to get/put the transport module. This prevents the
module unloading while sockets are assigned to it.

We increase the module refcnt when a socket is assigned to a
transport, and we decrease the module refcnt when the socket
is destructed.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Jorgen Hansen <jhansen@vmware.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

vsock/vmci: register vmci_transport only when VMCI guest/host are active

To allow other transports to be loaded with vmci_transport,
we register the vmci_transport as G2H or H2G only when a VMCI guest
or host is active.

To do that, this patch adds a callback registered in the vmci driver
that will be called when the host or guest becomes active.
This callback will register the vmci_transport in the VSOCK core.

Cc: Jorgen Hansen <jhansen@vmware.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

vsock: add multi-transports support

This patch adds the support of multiple transports in the
VSOCK core.

With the multi-transports support, we can use vsock with nested VMs
(using also different hypervisors) loading both guest->host and
host->guest transports at the same time.

Major changes:
- vsock core module can be loaded regardless of the transports
- vsock_core_init() and vsock_core_exit() are renamed to
vsock_core_register() and vsock_core_unregister()
- vsock_core_register() has a feature parameter (H2G, G2H, DGRAM)
to identify which directions the transport can handle and if it's
support DGRAM (only vmci)
- each stream socket is assigned to a transport when the remote CID
is set (during the connect() or when we receive a connection request
on a listener socket).
The remote CID is used to decide which transport to use:
- remote CID <= VMADDR_CID_HOST will use guest->host transport;
- remote CID == local_cid (guest->host transport) will use guest->host
transport for loopback (host->guest transports don't support loopback);
- remote CID > VMADDR_CID_HOST will use host->guest transport;
- listener sockets are not bound to any transports since no transport
operations are done on it. In this way we can create a listener
socket, also if the transports are not loaded or with VMADDR_CID_ANY
to listen on all transports.
- DGRAM sockets are handled as before, since only the vmci_transport
provides this feature.

Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

vsock: add vsock_create_connected() called by transports

All transports call __vsock_create() with the same parameters,
most of them depending on the parent socket. In order to simplify
the VSOCK core APIs exposed to the transports, this patch adds
the vsock_create_connected() callable from transports to create
a new socket when a connection request is received.
We also unexported the __vsock_create().

Suggested-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Jorgen Hansen <jhansen@vmware.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

vsock: handle buffer_size sockopts in the core

virtio_transport and vmci_transport handle the buffer_size
sockopts in a very similar way.

In order to support multiple transports, this patch moves this
handling in the core to allow the user to change the options
also if the socket is not yet assigned to any transport.

This patch also adds the '.notify_buffer_size' callback in the
'struct virtio_transport' in order to inform the transport,
when the buffer_size is changed by the user. It is also useful
to limit the 'buffer_size' requested (e.g. virtio transports).

Acked-by: Dexuan Cui <decui@microsoft.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Jorgen Hansen <jhansen@vmware.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

vsock/vmci: remove unused VSOCK_DEFAULT_CONNECT_TIMEOUT

The VSOCK_DEFAULT_CONNECT_TIMEOUT definition was introduced with
commit d021c344051af ("VSOCK: Introduce VM Sockets"), but it is
never used in the net/vmw_vsock/vmci_transport.c.

VSOCK_DEFAULT_CONNECT_TIMEOUT is used and defined in
net/vmw_vsock/af_vsock.c

Cc: Jorgen Hansen <jhansen@vmware.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Jorgen Hansen <jhansen@vmware.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: use helpers to change sk_ack_backlog

Writers are holding a lock, but many readers do not.

Following patch will add appropriate barriers in
sk_acceptq_removed() and sk_acceptq_added().

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 321

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation version 2 and no later version this
program is distributed in the hope that it will be useful but
without any warranty without even the implied warranty of
merchantability or fitness for a particular purpose see the gnu
general public license for more details

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 33 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190530000435.345978407@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

vsock: cope with memory allocation failure at socket creation time

In the unlikely event that the kmalloc call in vmci_transport_socket_init()
fails, we end-up calling vmci_transport_destruct() with a NULL vmci_trans()
and oopsing.

This change addresses the above explicitly checking for zero vmci_trans()
at destruction time.

Reported-by: Xiumei Mu <xmu@redhat.com>
Fixes: d021c344051a ("VSOCK: Introduce VM Sockets")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Jorgen Hansen <jhansen@vmware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

VSOCK: Send reset control packet when socket is partially bound

If a server side socket is bound to an address, but not in the listening
state yet, incoming connection requests should receive a reset control
packet in response. However, the function used to send the reset
silently drops the reset packet if the sending socket isn't bound
to a remote address (as is the case for a bound socket not yet in
the listening state). This change fixes this by using the src
of the incoming packet as destination for the reset packet in
this case.

Fixes: d021c344051a ("VSOCK: Introduce VM Sockets")
Reviewed-by: Adit Ranadive <aditr@vmware.com>
Reviewed-by: Vishnu Dasa <vdasa@vmware.com>
Signed-off-by: Jorgen Hansen <jhansen@vmware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

vsock: split dwork to avoid reinitializations

syzbot reported that we reinitialize an active delayed
work in vsock_stream_connect():

ODEBUG: init active (active state 0) object type: timer_list hint:
delayed_work_timer_fn+0x0/0x90 kernel/workqueue.c:1414
WARNING: CPU: 1 PID: 11518 at lib/debugobjects.c:329
debug_print_object+0x16a/0x210 lib/debugobjects.c:326

The pattern is apparently wrong, we should only initialize
the dealyed work once and could repeatly schedule it. So we
have to move out the initializations to allocation side.
And to avoid confusion, we can split the shared dwork
into two, instead of re-using the same one.

Fixes: d021c344051a ("VSOCK: Introduce VM Sockets")
Reported-by: <syzbot+8a9b1bd330476a4f3db6@syzkaller.appspotmail.com>
Cc: Andy king <acking@vmware.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Jorgen Hansen <jhansen@vmware.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

VSOCK: Don't set sk_state to TCP_CLOSE before testing it

A recent commit (3b4477d2dcf2) converted the sk_state to use
TCP constants. In that change, vmci_transport_handle_detach
was changed such that sk->sk_state was set to TCP_CLOSE before
we test whether it is TCP_SYN_SENT. This change moves the
sk_state change back to the original locations in that function.

Signed-off-by: Jorgen Hansen <jhansen@vmware.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

VSOCK: Don't call vsock_stream_has_data in atomic context

When using the host personality, VMCI will grab a mutex for any
queue pair access. In the detach callback for the vmci vsock
transport, we call vsock_stream_has_data while holding a spinlock,
and vsock_stream_has_data will access a queue pair.

To avoid this, we can simply omit calling vsock_stream_has_data
for host side queue pairs, since the QPs are empty per default
when the guest has detached.

This bug affects users of VMware Workstation using kernel version
4.4 and later.

Testing: Ran vsock tests between guest and host, and verified that
with this change, the host isn't calling vsock_stream_has_data
during detach. Ran mixedTest between guest and host using both
guest and host as server.

v2: Rebased on top of recent change to sk_state values
Reviewed-by: Adit Ranadive <aditr@vmware.com>
Reviewed-by: Aditya Sarwade <asarwade@vmware.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Jorgen Hansen <jhansen@vmware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

VSOCK: use TCP state constants for sk_state

There are two state fields: socket->state and sock->sk_state. The
socket->state field uses SS_UNCONNECTED, SS_CONNECTED, etc while the
sock->sk_state typically uses values that match TCP state constants
(TCP_CLOSE, TCP_ESTABLISHED). AF_VSOCK does not follow this convention
and instead uses SS_* constants for both fields.

The sk_state field will be exposed to userspace through the vsock_diag
interface for ss(8), netstat(8), and other programs.

This patch switches sk_state to TCP state constants so that the meaning
of this field is consistent with other address families. Not just
AF_INET and AF_INET6 use the TCP constants, AF_UNIX and others do too.

The following mapping was used to convert the code:

SS_FREE -> TCP_CLOSE
SS_UNCONNECTED -> TCP_CLOSE
SS_CONNECTING -> TCP_SYN_SENT
SS_CONNECTED -> TCP_ESTABLISHED
SS_DISCONNECTING -> TCP_CLOSING
VSOCK_SS_LISTEN -> TCP_LISTEN

In __vsock_create() the sk_state initialization was dropped because
sock_init_data() already initializes sk_state to TCP_CLOSE.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

vsock: vmci: Remove unneeded linux/miscdevice.h include

net/vmw_vsock/vmci_transport.c does not use any miscdevice so this patch
remove this unnecessary inclusion.

Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

VSOCK: remove unnecessary ternary operator on return value

Rather than assign the positive errno values to ret and then
checking if it is positive and flip the sign, just return the
errno value.

Detected by CoverityScan, CID#986649 ("Logically Dead Code")

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Jorgen Hansen <jhansen@vmware.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

VSOCK: defer sock removal to transports

The virtio transport will implement graceful shutdown and the related
SO_LINGER socket option. This requires orphaning the sock but keeping
it in the table of connections after .release().

This patch adds the vsock_remove_sock() function and leaves it up to the
transport when to remove the sock.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

VSOCK: constify vsock_transport structure

The vsock_transport structure is never modified, so declare it as const.

Done with the help of Coccinelle.

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>

VSOCK: Only check error on skb_recv_datagram when skb is NULL

If skb_recv_datagram returns an skb, we should ignore the err
value returned. Otherwise, datagram receives will return EAGAIN
when they have to wait for a datagram.

Acked-by: Adit Ranadive <aditr@vmware.com>
Signed-off-by: Jorgen Hansen <jhansen@vmware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

VSOCK: Detach QP check should filter out non matching QPs.

The check in vmci_transport_peer_detach_cb should only allow a
detach when the qp handle of the transport matches the one in
the detach message.

Testing: Before this change, a detach from a peer on a different
socket would cause an active stream socket to register a detach.

Reviewed-by: George Zhang <georgezhang@vmware.com>
Signed-off-by: Jorgen Hansen <jhansen@vmware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

VSOCK: call sk->sk_data_ready() on accept()

When a listen socket enqueues a connection for userspace to accept(),
the sk->sk_data_ready() callback should be invoked. In-kernel socket
users rely on this callback to detect when incoming connections are
available.

Currently the sk->sk_state_change() callback is invoked by
vmci_transport.c. This happens to work for userspace applications since
sk->sk_state_change = sock_def_wakeup() and sk->sk_data_ready =
sock_def_readable() both wake up the accept() waiter. In-kernel socket
users, on the other hand, fail to detect incoming connections.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

VSOCK: define VSOCK_SS_LISTEN once only

The SS_LISTEN socket state is defined by both af_vsock.c and
vmci_transport.c. This is risky since the value could be changed in one
file and the other would be out of sync.

Rename from SS_LISTEN to VSOCK_SS_LISTEN since the constant is not part
of enum socket_state (SS_CONNECTED, ...). This way it is clear that the
constant is vsock-specific.

The big text reflow in af_vsock.c was necessary to keep to the maximum
line length. Text is unchanged except for s/SS_LISTEN/VSOCK_SS_LISTEN/.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

VSOCK: Fix lockdep issue.

The recent fix for the vsock sock_put issue used the wrong
initializer for the transport spin_lock causing an issue when
running with lockdep checking.

Testing: Verified fix on kernel with lockdep enabled.

Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Jorgen Hansen <jhansen@vmware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

VSOCK: sock_put wasn't safe to call in interrupt context

In the vsock vmci_transport driver, sock_put wasn't safe to call
in interrupt context, since that may call the vsock destructor
which in turn calls several functions that should only be called
from process context. This change defers the callling of these
functions to a worker thread. All these functions were
deallocation of resources related to the transport itself.

Furthermore, an unused callback was removed to simplify the
cleanup.

Multiple customers have been hitting this issue when using
VMware tools on vSphere 2015.

Also added a version to the vmci transport module (starting from
1.0.2.0-k since up until now it appears that this module was
sharing version with vsock that is currently at 1.0.1.0-k).

Reviewed-by: Aditya Asarwade <asarwade@vmware.com>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Jorgen Hansen <jhansen@vmware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: Pass kern from net_proto_family.create to sk_alloc

In preparation for changing how struct net is refcounted
on kernel sockets pass the knowledge that we are creating
a kernel socket from sock_create_kern through to sk_alloc.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: Remove iocb argument from sendmsg and recvmsg

After TIPC doesn't depend on iocb argument in its internal
implementations of sendmsg() and recvmsg() hooks defined in proto
structure, no any user is using iocb argument in them at all now.
Then we can drop the redundant iocb argument completely from kinds of
implementations of both sendmsg() and recvmsg() in the entire
networking stack.

Cc: Christoph Hellwig <hch@lst.de>
Suggested-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

vmci: propagate msghdr all way down to __qp_memcpy_to_queue()

Switch from passing msg->iov_iter.iov to passing msg itself

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

put iov_iter into msghdr

Note that the code _using_ ->msg_iter at that point will be very
unhappy with anything other than unshifted iovec-backed iov_iter.
We still need to convert users to proper primitives.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

vmci: propagate msghdr all way down to __qp_memcpy_from_queue()

... and switch it to memcpy_to_msg()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

vmci_transport: switch ->enqeue_dgram, ->enqueue_stream and ->dequeue_stream to msghdr

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

net: Add and use skb_copy_datagram_msg() helper.

This encapsulates all of the skb_copy_datagram_iovec() callers
with call argument signature "skb, offset, msghdr->msg_iov, length".

When we move to iov_iters in the networking, the iov_iter object will
sit in the msghdr.

Having a helper like this means there will be less places to touch
during that transformation.

Based upon descriptions and patch from Al Viro.

Signed-off-by: David S. Miller <davem@davemloft.net>

net: add build-time checks for msg->msg_name size

This is a follow-up patch to f3d3342602f8bc ("net: rework recvmsg
handler msg_name and msg_namelen logic").

DECLARE_SOCKADDR validates that the structure we use for writing the
name information to is not larger than the buffer which is reserved
for msg->msg_name (which is 128 bytes). Also use DECLARE_SOCKADDR
consistently in sendmsg code paths.

Signed-off-by: Steffen Hurrle <steffen@hurrle.net>
Suggested-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: rework recvmsg handler msg_name and msg_namelen logic

This patch now always passes msg->msg_namelen as 0. recvmsg handlers must
set msg_namelen to the proper size <= sizeof(struct sockaddr_storage)
to return msg_name to the user.

This prevents numerous uninitialized memory leaks we had in the
recvmsg handlers and makes it harder for new code to accidentally leak
uninitialized memory.

Optimize for the case recvfrom is called with NULL as address. We don't
need to copy the address at all, so set it to NULL before invoking the
recvmsg handler. We can do so, because all the recvmsg handlers must
cope with the case a plain read() is called on them. read() also sets
msg_name to NULL.

Also document these changes in include/linux/net.h as suggested by David
Miller.

Changes since RFC:

Set msg->msg_name = NULL if user specified a NULL in msg_name but had a
non-null msg_namelen in verify_iovec/verify_compat_iovec. This doesn't
affect sendto as it would bail out earlier while trying to copy-in the
address. It also more naturally reflects the logic by the callers of
verify_iovec.

With this change in place I could remove "
if (!uaddr || msg_sys->msg_namelen == 0)
msg->msg_name = NULL
".

This change does not alter the user visible error logic as we ignore
msg_namelen as long as msg_name is NULL.

Also remove two unnecessary curly brackets in ___sys_recvmsg and change
comments to netdev style.

Cc: David Miller <davem@davemloft.net>
Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

VSOCK: Move af_vsock.h and vsock_addr.h to include/net

This is useful for other VSOCK transport implemented outside the
net/vmw_vsock/ directory to use these headers.

Signed-off-by: Asias He <asias@redhat.com>
Acked-by: Andy King <acking@vmware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

VSOCK: Remove unnecessary label

Signed-off-by: Asias He <asias@redhat.com>
Acked-by: Andy King <acking@vmware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

VSOCK: Return VMCI_ERROR_NO_MEM when fails to allocate skb

vmci_transport_recv_dgram_cb always return VMCI_SUCESS even if we fail
to allocate skb, return VMCI_ERROR_NO_MEM instead.

Signed-off-by: Asias He <asias@redhat.com>
Acked-by: Andy King <acking@vmware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

VSOCK: vmci - fix possible info leak in vmci_transport_dgram_dequeue()

In case we received no data on the call to skb_recv_datagram(), i.e.
skb->data is NULL, vmci_transport_dgram_dequeue() will return with 0
without updating msg_namelen leading to net/socket.c leaking the local,
uninitialized sockaddr_storage variable to userland -- 128 bytes of
kernel stack memory.

Fix this by moving the already existing msg_namelen assignment a few
lines above.

Cc: Andy King <acking@vmware.com>
Cc: Dmitry Torokhov <dtor@vmware.com>
Cc: George Zhang <georgezhang@vmware.com>
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

VSOCK: Handle changes to the VMCI context ID.

The VMCI context ID of a virtual machine may change at any time. There
is a VMCI event which signals this but datagrams may be processed before
this is handled. It is therefore necessary to be flexible about the
destination context ID of any datagrams received. (It can be assumed to
be correct because it is provided by the hypervisor.) The context ID on
existing sockets should be updated to reflect how the hypervisor is
currently referring to the system.

Signed-off-by: Reilly Grant <grantr@vmware.com>
Acked-by: Andy King <acking@vmware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

VSOCK: Support VM sockets connected to the hypervisor.

The resource ID used for VM socket control packets (0) is already
used for the VMCI_GET_CONTEXT_ID hypercall so a new ID (15) must be
used when the guest sends these datagrams to the hypervisor.

The hypervisor context ID must also be removed from the internal
blacklist.

Signed-off-by: Reilly Grant <grantr@vmware.com>
Acked-by: Andy King <acking@vmware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

VSOCK: get rid of EXPORT_SYMTAB

This is the default behavior for a looooooong time.

Acked-by: Andy King <acking@vmware.com>
Signed-off-by: Dmitry Torokhov <dtor@vmware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

VSOCK: Introduce VM Sockets

VM Sockets allows communication between virtual machines and the hypervisor.
User level applications both in a virtual machine and on the host can use the
VM Sockets API, which facilitates fast and efficient communication between
guest virtual machines and their host. A socket address family, designed to be
compatible with UDP and TCP at the interface level, is provided.

Today, VM Sockets is used by various VMware Tools components inside the guest
for zero-config, network-less access to VMware host services. In addition to
this, VMware's users are using VM Sockets for various applications, where
network access of the virtual machine is restricted or non-existent. Examples
of this are VMs communicating with device proxies for proprietary hardware
running as host applications and automated testing of applications running
within virtual machines.

The VMware VM Sockets are similar to other socket types, like Berkeley UNIX
socket interface. The VM Sockets module supports both connection-oriented
stream sockets like TCP, and connectionless datagram sockets like UDP. The VM
Sockets protocol family is defined as "AF_VSOCK" and the socket operations
split for SOCK_DGRAM and SOCK_STREAM.

For additional information about the use of VM Sockets, please refer to the
VM Sockets Programming Guide available at:

https://www.vmware.com/support/developer/vmci-sdk/

Signed-off-by: George Zhang <georgezhang@vmware.com>
Signed-off-by: Dmitry Torokhov <dtor@vmware.com>
Signed-off-by: Andy king <acking@vmware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>