[ Upstream commit 49b0b6ffe20c5344f4173f3436298782a08da4f2 ]
There's a potential deadlock case when remove the vsock device or
process the RESET event:
vsock_for_each_connected_socket:
spin_lock_bh(&vsock_table_lock) ----------- (1)
...
virtio_vsock_reset_sock:
lock_sock(sk) --------------------- (2)
...
spin_unlock_bh(&vsock_table_lock)
lock_sock() may do initiative schedule when the 'sk' is owned by
other thread at the same time, we would receivce a warning message
that "scheduling while atomic".
Even worse, if the next task (selected by the scheduler) try to
release a 'sk', it need to request vsock_table_lock and the deadlock
occur, cause the system into softlockup state.
Call trace:
queued_spin_lock_slowpath
vsock_remove_bound
vsock_remove_sock
virtio_transport_release
__vsock_release
vsock_release
__sock_release
sock_close
__fput
____fput
So we should not require sk_lock in this case, just like the behavior
in vhost_vsock or vmci.
Fixes: 0ea9e1d3a9 ("VSOCK: Introduce virtio_transport.ko")
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Longpeng(Mike) <longpeng2@huawei.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://lore.kernel.org/r/20210812053056.1699-1-longpeng2@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit c7ff9cff70601ea19245d997bb977344663434c7 ]
The client's sk_state will be set to TCP_ESTABLISHED if the server
replay the client's connect request.
However, if the client has pending signal, its sk_state will be set
to TCP_CLOSE without notify the server, so the server will hold the
corrupt connection.
client server
1. sk_state=TCP_SYN_SENT |
2. call ->connect() |
3. wait reply |
| 4. sk_state=TCP_ESTABLISHED
| 5. insert to connected list
| 6. reply to the client
7. sk_state=TCP_ESTABLISHED |
8. insert to connected list |
9. *signal pending* <--------------------- the user kill client
10. sk_state=TCP_CLOSE |
client is exiting... |
11. call ->release() |
virtio_transport_close
if (!(sk->sk_state == TCP_ESTABLISHED ||
sk->sk_state == TCP_CLOSING))
return true; *return at here, the server cannot notice the connection is corrupt*
So the client should notify the peer in this case.
Cc: David S. Miller <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Jorgen Hansen <jhansen@vmware.com>
Cc: Norbert Slusarek <nslusarek@gmx.net>
Cc: Andra Paraschiv <andraprs@amazon.com>
Cc: Colin Ian King <colin.king@canonical.com>
Cc: David Brazdil <dbrazdil@google.com>
Cc: Alexander Popov <alex.popov@linux.com>
Suggested-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://lkml.org/lkml/2021/5/17/418
Signed-off-by: lixianming <lixianming5@huawei.com>
Signed-off-by: Longpeng(Mike) <longpeng2@huawei.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 8432b8114957235f42e070a16118a7f750de9d39 ]
As reported by syzbot [1], there is a memory leak while closing the
socket. We partially solved this issue with commit ac03046ece
("vsock/virtio: free packets during the socket release"), but we
forgot to drain the RX queue when the socket is definitely closed by
the scheduled work.
To avoid future issues, let's use the new virtio_transport_remove_sock()
to drain the RX queue before removing the socket from the af_vsock lists
calling vsock_remove_sock().
[1] https://syzkaller.appspot.com/bug?extid=24452624fc4c571eedd9
Fixes: ac03046ece ("vsock/virtio: free packets during the socket release")
Reported-and-tested-by: syzbot+24452624fc4c571eedd9@syzkaller.appspotmail.com
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit e16edc99d658cd41c60a44cc14d170697aa3271f ]
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: d021c34405 ("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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 1f935e8e72ec28dddb2dc0650b3b6626a293d94b ]
For AF_VSOCK, accept() currently returns sockets that are unlabelled.
Other socket families derive the child's SID from the SID of the parent
and the SID of the incoming packet. This is typically done as the
connected socket is placed in the queue that accept() removes from.
Reuse the existing 'security_sk_clone' hook to copy the SID from the
parent (server) socket to the child. There is no packet SID in this
case.
Fixes: d021c34405 ("VSOCK: Introduce VM Sockets")
Signed-off-by: David Brazdil <dbrazdil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 1c5fae9c9a092574398a17facc31c533791ef232 upstream.
In vsock_shutdown() we touched some socket fields without holding the
socket lock, such as 'state' and 'sk_flags'.
Also, after the introduction of multi-transport, we are accessing
'vsk->transport' in vsock_send_shutdown() without holding the lock
and this call can be made while the connection is in progress, so
the transport can change in the meantime.
To avoid issues, we hold the socket lock when we enter in
vsock_shutdown() and release it when we leave.
Among the transports that implement the 'shutdown' callback, only
hyperv_transport acquired the lock. Since the caller now holds it,
we no longer take it.
Fixes: d021c34405 ("VSOCK: Introduce VM Sockets")
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ce7536bc7398e2ae552d2fabb7e0e371a9f1fe46 upstream.
If the socket is closed or is being released, some resources used by
virtio_transport_space_update() such as 'vsk->trans' may be released.
To avoid a use after free bug we should only update the available credit
when we are sure the socket is still open and we have the lock held.
Fixes: 06a8fc7836 ("VSOCK: Introduce virtio_vsock_common.ko")
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Link: https://lore.kernel.org/r/20210208144454.84438-1-sgarzare@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3d0bc44d39bca615b72637e340317b7899b7f911 upstream.
A possible locking issue in vsock_connect_timeout() was recognized by
Eric Dumazet which might cause a null pointer dereference in
vsock_transport_cancel_pkt(). This patch assures that
vsock_transport_cancel_pkt() will be called within the lock, so a race
condition won't occur which could result in vsk->transport to be set to NULL.
Fixes: 380feae0de ("vsock: cancel packets when failing to connect")
Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Norbert Slusarek <nslusarek@gmx.net>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://lore.kernel.org/r/trinity-f8e0937a-cf0e-4d80-a76e-d9a958ba3ef1-1612535522360@3c-app-gmx-bap12
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 5d1cbcc990f18edaddddef26677073c4e6fad7b7 upstream.
In vsock_stream_connect(), a thread will enter schedule_timeout().
While being scheduled out, another thread can enter vsock_stream_connect()
as well and set vsk->transport to NULL. In case a signal was sent, the
first thread can leave schedule_timeout() and vsock_transport_cancel_pkt()
will be called right after. Inside vsock_transport_cancel_pkt(), a null
dereference will happen on transport->cancel_pkt.
Fixes: c0cfa2d8a7 ("vsock: add multi-transports support")
Signed-off-by: Norbert Slusarek <nslusarek@gmx.net>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://lore.kernel.org/r/trinity-c2d6cede-bfb1-44e2-85af-1fbc7f541715-1612535117028@3c-app-gmx-bap12
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c518adafa39f37858697ac9309c6cf1805581446 upstream.
There are multiple similar bugs implicitly introduced by the
commit c0cfa2d8a7 ("vsock: add multi-transports support") and
commit 6a2c096210 ("vsock: prevent transport modules unloading").
The bug pattern:
[1] vsock_sock.transport pointer is copied to a local variable,
[2] lock_sock() is called,
[3] the local variable is used.
VSOCK multi-transport support introduced the race condition:
vsock_sock.transport value may change between [1] and [2].
Let's copy vsock_sock.transport pointer to local variables after
the lock_sock() call.
Fixes: c0cfa2d8a7 ("vsock: add multi-transports support")
Signed-off-by: Alexander Popov <alex.popov@linux.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Jorgen Hansen <jhansen@vmware.com>
Link: https://lore.kernel.org/r/20210201084719.2257066-1-alex.popov@linux.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Starting from commit 8692cefc43 ("virtio_vsock: Fix race condition
in virtio_transport_recv_pkt"), we discard packets in
virtio_transport_recv_pkt() if the socket has been released.
When the socket is connected, we schedule a delayed work to wait the
RST packet from the other peer, also if SHUTDOWN_MASK is set in
sk->sk_shutdown.
This is done to complete the virtio-vsock shutdown algorithm, releasing
the port assigned to the socket definitively only when the other peer
has consumed all the packets.
If we discard the RST packet received, the socket will be closed only
when the VSOCK_CLOSE_TIMEOUT is reached.
Sergio discovered the issue while running ab(1) HTTP benchmark using
libkrun [1] and observing a latency increase with that commit.
To avoid this issue, we discard packet only if the socket is really
closed (SOCK_DONE flag is set).
We also set SOCK_DONE in virtio_transport_release() when we don't need
to wait any packets from the other peer (we didn't schedule the delayed
work). In this case we remove the socket from the vsock lists, releasing
the port assigned.
[1] https://github.com/containers/libkrun
Fixes: 8692cefc43 ("virtio_vsock: Fix race condition in virtio_transport_recv_pkt")
Cc: justin.he@arm.com
Reported-by: Sergio Lopez <slp@redhat.com>
Tested-by: Sergio Lopez <slp@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Acked-by: Jia He <justin.he@arm.com>
Link: https://lore.kernel.org/r/20201120104736.73749-1-sgarzare@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Before commit c0cfa2d8a7 ("vsock: add multi-transports support"),
if a G2H transport was loaded (e.g. virtio transport), every packets
was forwarded to the host, regardless of the destination CID.
The H2G transports implemented until then (vhost-vsock, VMCI) always
responded with an error, if the destination CID was not
VMADDR_CID_HOST.
From that commit, we are using the remote CID to decide which
transport to use, so packets with remote CID > VMADDR_CID_HOST(2)
are sent only through H2G transport. If no H2G is available, packets
are discarded directly in the guest.
Some use cases (e.g. Nitro Enclaves [1]) rely on the old behaviour
to implement sibling VMs communication, so we restore the old
behavior when no H2G is registered.
It will be up to the host to discard packets if the destination is
not the right one. As it was already implemented before adding
multi-transport support.
Tested with nested QEMU/KVM by me and Nitro Enclaves by Andra.
[1] Documentation/virt/ne_overview.rst
Cc: Jorgen Hansen <jhansen@vmware.com>
Cc: Dexuan Cui <decui@microsoft.com>
Fixes: c0cfa2d8a7 ("vsock: add multi-transports support")
Reported-by: Andra Paraschiv <andraprs@amazon.com>
Tested-by: Andra Paraschiv <andraprs@amazon.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://lore.kernel.org/r/20201112133837.34183-1-sgarzare@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
During __vsock_create() CAP_NET_ADMIN is used to determine if the
vsock_sock->trusted should be set to true. This value is used later
for determing if a remote connection should be allowed to connect
to a restricted VM. Unfortunately, if the caller doesn't have
CAP_NET_ADMIN, an audit message such as an selinux denial is
generated even if the caller does not want a trusted socket.
Logging errors on success is confusing. To avoid this, switch the
capable(CAP_NET_ADMIN) check to the noaudit version.
Reported-by: Roman Kiryanov <rkir@google.com>
https://android-review.googlesource.com/c/device/generic/goldfish/+/1468545/
Signed-off-by: Jeff Vander Stoep <jeffv@google.com>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Link: https://lore.kernel.org/r/20201023143757.377574-1-jeffv@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
syzbot reported this issue where in the vsock_poll() we find the
socket state at TCP_ESTABLISHED, but 'transport' is null:
general protection fault, probably for non-canonical address 0xdffffc0000000012: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000090-0x0000000000000097]
CPU: 0 PID: 8227 Comm: syz-executor.2 Not tainted 5.8.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:vsock_poll+0x75a/0x8e0 net/vmw_vsock/af_vsock.c:1038
Call Trace:
sock_poll+0x159/0x460 net/socket.c:1266
vfs_poll include/linux/poll.h:90 [inline]
do_pollfd fs/select.c:869 [inline]
do_poll fs/select.c:917 [inline]
do_sys_poll+0x607/0xd40 fs/select.c:1011
__do_sys_poll fs/select.c:1069 [inline]
__se_sys_poll fs/select.c:1057 [inline]
__x64_sys_poll+0x18c/0x440 fs/select.c:1057
do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:384
entry_SYSCALL_64_after_hwframe+0x44/0xa9
This issue can happen if the TCP_ESTABLISHED state is set after we read
the vsk->transport in the vsock_poll().
We could put barriers to synchronize, but this can only happen during
connection setup, so we can simply check that 'transport' is valid.
Fixes: c0cfa2d8a7 ("vsock: add multi-transports support")
Reported-and-tested-by: syzbot+a61bac2fcc1a7c6623fe@syzkaller.appspotmail.com
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Jorgen Hansen <jhansen@vmware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The UDP reuseport conflict was a little bit tricky.
The net-next code, via bpf-next, extracted the reuseport handling
into a helper so that the BPF sk lookup code could invoke it.
At the same time, the logic for reuseport handling of unconnected
sockets changed via commit efc6b6f6c3
which changed the logic to carry on the reuseport result into the
rest of the lookup loop if we do not return immediately.
This requires moving the reuseport_has_conns() logic into the callers.
While we are here, get rid of inline directives as they do not belong
in foo.c files.
The other changes were cases of more straightforward overlapping
modifications.
Signed-off-by: David S. Miller <davem@davemloft.net>
Rework the remaining setsockopt code to pass a sockptr_t instead of a
plain user pointer. This removes the last remaining set_fs(KERNEL_DS)
outside of architecture specific code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Stefan Schmidt <stefan@datenfreihafen.org> [ieee802154]
Acked-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Just check for a NULL method instead of wiring up
sock_no_{get,set}sockopt.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
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: b1bba80a43 ("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>
When client on the host tries to connect(SOCK_STREAM, O_NONBLOCK) to the
server on the guest, there will be a panic on a ThunderX2 (armv8a server):
[ 463.718844] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
[ 463.718848] Mem abort info:
[ 463.718849] ESR = 0x96000044
[ 463.718852] EC = 0x25: DABT (current EL), IL = 32 bits
[ 463.718853] SET = 0, FnV = 0
[ 463.718854] EA = 0, S1PTW = 0
[ 463.718855] Data abort info:
[ 463.718856] ISV = 0, ISS = 0x00000044
[ 463.718857] CM = 0, WnR = 1
[ 463.718859] user pgtable: 4k pages, 48-bit VAs, pgdp=0000008f6f6e9000
[ 463.718861] [0000000000000000] pgd=0000000000000000
[ 463.718866] Internal error: Oops: 96000044 [#1] SMP
[...]
[ 463.718977] CPU: 213 PID: 5040 Comm: vhost-5032 Tainted: G O 5.7.0-rc7+ #139
[ 463.718980] Hardware name: GIGABYTE R281-T91-00/MT91-FS1-00, BIOS F06 09/25/2018
[ 463.718982] pstate: 60400009 (nZCv daif +PAN -UAO)
[ 463.718995] pc : virtio_transport_recv_pkt+0x4c8/0xd40 [vmw_vsock_virtio_transport_common]
[ 463.718999] lr : virtio_transport_recv_pkt+0x1fc/0xd40 [vmw_vsock_virtio_transport_common]
[ 463.719000] sp : ffff80002dbe3c40
[...]
[ 463.719025] Call trace:
[ 463.719030] virtio_transport_recv_pkt+0x4c8/0xd40 [vmw_vsock_virtio_transport_common]
[ 463.719034] vhost_vsock_handle_tx_kick+0x360/0x408 [vhost_vsock]
[ 463.719041] vhost_worker+0x100/0x1a0 [vhost]
[ 463.719048] kthread+0x128/0x130
[ 463.719052] ret_from_fork+0x10/0x18
The race condition is as follows:
Task1 Task2
===== =====
__sock_release virtio_transport_recv_pkt
__vsock_release vsock_find_bound_socket (found sk)
lock_sock_nested
vsock_remove_sock
sock_orphan
sk_set_socket(sk, NULL)
sk->sk_shutdown = SHUTDOWN_MASK
...
release_sock
lock_sock
virtio_transport_recv_connecting
sk->sk_socket->state (panic!)
The root cause is that vsock_find_bound_socket can't hold the lock_sock,
so there is a small race window between vsock_find_bound_socket() and
lock_sock(). If __vsock_release() is running in another task,
sk->sk_socket will be set to NULL inadvertently.
This fixes it by checking sk->sk_shutdown(suggested by Stefano) after
lock_sock since sk->sk_shutdown is set to SHUTDOWN_MASK under the
protection of lock_sock_nested.
Signed-off-by: Jia He <justin.he@arm.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The accept(2) is an "input" socket interface, so we should use
SO_RCVTIMEO instead of SO_SNDTIMEO to set the timeout.
So this patch replace sock_sndtimeo() with sock_rcvtimeo() to
use the right timeout in the vsock_accept().
Fixes: d021c34405 ("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>
In virtio_transport.c, if the virtqueue is full, the transmitting
packet is queued up and it will be sent in the next iteration.
This causes the same packet to be delivered multiple times to
monitoring devices.
We want to continue to deliver packets to monitoring devices before
it is put in the virtqueue, to avoid that replies can appear in the
packet capture before the transmitted packet.
This patch fixes the issue, adding a new flag (tap_delivered) in
struct virtio_vsock_pkt, to check if the packet is already delivered
to monitoring devices.
In vhost/vsock.c, we are splitting packets, so we must set
'tap_delivered' to false when we queue up the same virtio_vsock_pkt
to handle the remaining bytes.
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The mptcp conflict was overlapping additions.
The SMC conflict was an additional and removal happening at the same
time.
Signed-off-by: David S. Miller <davem@davemloft.net>
Some transports (hyperv, virtio) acquire the sock lock during the
.release() callback.
In the vsock_stream_connect() we call vsock_assign_transport(); if
the socket was previously assigned to another transport, the
vsk->transport->release() is called, but the sock lock is already
held in the vsock_stream_connect(), causing a deadlock reported by
syzbot:
INFO: task syz-executor280:9768 blocked for more than 143 seconds.
Not tainted 5.6.0-rc1-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor280 D27912 9768 9766 0x00000000
Call Trace:
context_switch kernel/sched/core.c:3386 [inline]
__schedule+0x934/0x1f90 kernel/sched/core.c:4082
schedule+0xdc/0x2b0 kernel/sched/core.c:4156
__lock_sock+0x165/0x290 net/core/sock.c:2413
lock_sock_nested+0xfe/0x120 net/core/sock.c:2938
virtio_transport_release+0xc4/0xd60 net/vmw_vsock/virtio_transport_common.c:832
vsock_assign_transport+0xf3/0x3b0 net/vmw_vsock/af_vsock.c:454
vsock_stream_connect+0x2b3/0xc70 net/vmw_vsock/af_vsock.c:1288
__sys_connect_file+0x161/0x1c0 net/socket.c:1857
__sys_connect+0x174/0x1b0 net/socket.c:1874
__do_sys_connect net/socket.c:1885 [inline]
__se_sys_connect net/socket.c:1882 [inline]
__x64_sys_connect+0x73/0xb0 net/socket.c:1882
do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
entry_SYSCALL_64_after_hwframe+0x49/0xbe
To avoid this issue, this patch remove the lock acquiring in the
.release() callback of hyperv and virtio transports, and it holds
the lock when we call vsk->transport->release() in the vsock core.
Reported-by: syzbot+731710996d79d0d58fbc@syzkaller.appspotmail.com
Fixes: 408624af4c ("vsock: use local transport when it is loaded")
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Whenever the vsock backend on the host sends a packet through the RX
queue, it expects an answer on the TX queue. Unfortunately, there is one
case where the host side will hang waiting for the answer and might
effectively never recover if no timeout mechanism was implemented.
This issue happens when the guest side starts binding to the socket,
which insert a new bound socket into the list of already bound sockets.
At this time, we expect the guest to also start listening, which will
trigger the sk_state to move from TCP_CLOSE to TCP_LISTEN. The problem
occurs if the host side queued a RX packet and triggered an interrupt
right between the end of the binding process and the beginning of the
listening process. In this specific case, the function processing the
packet virtio_transport_recv_pkt() will find a bound socket, which means
it will hit the switch statement checking for the sk_state, but the
state won't be changed into TCP_LISTEN yet, which leads the code to pick
the default statement. This default statement will only free the buffer,
while it should also respond to the host side, by sending a packet on
its TX queue.
In order to simply fix this unfortunate chain of events, it is important
that in case the default statement is entered, and because at this stage
we know the host side is waiting for an answer, we must send back a
packet containing the operation VIRTIO_VSOCK_OP_RST.
One could say that a proper timeout mechanism on the host side will be
enough to avoid the backend to hang. But the point of this patch is to
ensure the normal use case will be provided with proper responsiveness
when it comes to establishing the connection.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, hv_sock restricts the port the guest socket can accept
connections on. hv_sock divides the socket port namespace into two parts
for server side (listening socket), 0-0x7FFFFFFF & 0x80000000-0xFFFFFFFF
(there are no restrictions on client port namespace). The first part
(0-0x7FFFFFFF) is reserved for sockets where connections can be accepted.
The second part (0x80000000-0xFFFFFFFF) is reserved for allocating ports
for the peer (host) socket, once a connection is accepted.
This reservation of the port namespace is specific to hv_sock and not
known by the generic vsock library (ex: af_vsock). This is problematic
because auto-binds/ephemeral ports are handled by the generic vsock
library and it has no knowledge of this port reservation and could
allocate a port that is not compatible with hv_sock (and legitimately so).
The issue hasn't surfaced so far because the auto-bind code of vsock
(__vsock_bind_stream) prior to the change 'VSOCK: bind to random port for
VMADDR_PORT_ANY' would start walking up from LAST_RESERVED_PORT (1023) and
start assigning ports. That will take a large number of iterations to hit
0x7FFFFFFF. But, after the above change to randomize port selection, the
issue has started coming up more frequently.
There has really been no good reason to have this port reservation logic
in hv_sock from the get go. Reserving a local port for peer ports is not
how things are handled generally. Peer ports should reflect the peer port.
This fixes the issue by lifting the port reservation, and also returns the
right peer port. Since the code converts the GUID to the peer port (by
using the first 4 bytes), there is a possibility of conflicts, but that
seems like a reasonable risk to take, given this is limited to vsock and
that only applies to all local sockets.
Signed-off-by: Sunil Muthuswamy <sunilmut@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
virtio_transport_get_ops() and virtio_transport_send_pkt_info()
can only be used on connecting/connected sockets, since a socket
assigned to a transport is required.
This patch adds a WARN_ON() on virtio_transport_get_ops() to check
this requirement, a comment and a returned error on
virtio_transport_send_pkt_info(),
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We can remove the loopback handling from virtio_transport,
because now the vsock core is able to handle local communication
using the new vsock_loopback device.
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now that we have a transport that can handle the local communication,
we can use it when it is loaded.
A socket will use the local transport (loopback) when the remote
CID is:
- equal to VMADDR_CID_LOCAL
- or equal to transport_g2h->get_local_cid(), if transport_g2h
is loaded (this allows us to keep the same behavior implemented
by virtio and vmci transports)
- or equal to VMADDR_CID_HOST, if transport_g2h is not loaded
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds a new vsock_loopback transport to handle local
communication.
This transport is based on the loopback implementation of
virtio_transport, so it uses the virtio_transport_common APIs
to interface with the vsock core.
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch allows to register a transport able to handle
local communication (loopback).
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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>
We can remove virtio header includes, because virtio_transport_common
doesn't use virtio API, but provides common functions to interface
virtio/vhost transports with the af_vsock core, and to handle
the protocol.
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
- Hibernation support (Dexuan Cui).
- Latency testing framework (Branden Bonaby).
- Decoupling Hyper-V page size from guest page size (Himadri Pandya).
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Merge tag 'hyperv-next-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux
Pull Hyper-V updates from Sasha Levin:
- support for new VMBus protocols (Andrea Parri)
- hibernation support (Dexuan Cui)
- latency testing framework (Branden Bonaby)
- decoupling Hyper-V page size from guest page size (Himadri Pandya)
* tag 'hyperv-next-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux: (22 commits)
Drivers: hv: vmbus: Fix crash handler reset of Hyper-V synic
drivers/hv: Replace binary semaphore with mutex
drivers: iommu: hyperv: Make HYPERV_IOMMU only available on x86
HID: hyperv: Add the support of hibernation
hv_balloon: Add the support of hibernation
x86/hyperv: Implement hv_is_hibernation_supported()
Drivers: hv: balloon: Remove dependencies on guest page size
Drivers: hv: vmbus: Remove dependencies on guest page size
x86: hv: Add function to allocate zeroed page for Hyper-V
Drivers: hv: util: Specify ring buffer size using Hyper-V page size
Drivers: hv: Specify receive buffer size using Hyper-V page size
tools: hv: add vmbus testing tool
drivers: hv: vmbus: Introduce latency testing
video: hyperv: hyperv_fb: Support deferred IO for Hyper-V frame buffer driver
video: hyperv: hyperv_fb: Obtain screen resolution from Hyper-V host
hv_netvsc: Add the support of hibernation
hv_sock: Add the support of hibernation
video: hyperv_fb: Add the support of hibernation
scsi: storvsc: Add the support of hibernation
Drivers: hv: vmbus: Add module parameter to cap the VMBus version
...
Add the necessary dummy callbacks for hibernation.
Signed-off-by: Dexuan Cui <decui@microsoft.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
If transport->init() fails, we can't assign the transport to the
socket, because it's not initialized correctly, and any future
calls to the transport callbacks would have an unexpected behavior.
Fixes: c0cfa2d8a7 ("vsock: add multi-transports support")
Reported-and-tested-by: syzbot+e2e5c07bf353b2f79daa@syzkaller.appspotmail.com
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Jorgen Hansen <jhansen@vmware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When we are looking for a socket bound to a specific address,
we also have to take into account the CID.
This patch is useful with multi-transports support because it
allows the binding of the same port with different CID, and
it prevents a connection to a wrong socket bound to the same
port, but with different CID.
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>
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>
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>
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>
Remote peer is always the host, so we set VMADDR_CID_HOST as
remote CID instead of VMADDR_CID_ANY.
Reviewed-by: Dexuan Cui <decui@microsoft.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
vsock_insert_unbound() was called only when 'sock' parameter of
__vsock_create() was not null. This only happened when
__vsock_create() was called by vsock_create().
In order to simplify the multi-transports support, this patch
moves vsock_insert_unbound() at the end of vsock_create().
Reviewed-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>
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>
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>
Since now the 'struct vsock_sock' object contains a pointer to
the transport, this patch adds a parameter to the
vsock_core_get_transport() to return the right transport
assigned to the socket.
This patch modifies also the virtio_transport_get_ops(), that
uses the vsock_core_get_transport(), adding the
'struct vsock_sock *' parameter.
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>
We are going to add 'struct vsock_sock *' parameter to
virtio_transport_get_ops().
In some cases, like in the virtio_transport_reset_no_sock(),
we don't have any socket assigned to the packet received,
so we can't use the virtio_transport_get_ops().
In order to allow virtio_transport_reset_no_sock() to use the
'.send_pkt' callback from the 'vhost_transport' or 'virtio_transport',
we add the 'struct virtio_transport *' to it and to its caller:
virtio_transport_recv_pkt().
We moved the 'vhost_transport' and 'virtio_transport' definition,
to pass their address to the virtio_transport_recv_pkt().
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As a preparation to support multiple transports, this patch adds
the 'transport' member at the 'struct vsock_sock'.
This new field is initialized during the creation in the
__vsock_create() function.
This patch also renames the global 'transport' pointer to
'transport_single', since for now we're only supporting a single
transport registered at run-time.
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>
