The vsock flags field can be set in the connect path (user space app)
and the (listen) receive path (kernel space logic).
When the vsock transport is assigned, the remote CID is used to
distinguish between types of connection.
Use the vsock flags value (in addition to the CID) from the remote
address to decide which vsock transport to assign. For the sibling VMs
use case, all the vsock packets need to be forwarded to the host, so
always assign the guest->host transport if the VMADDR_FLAG_TO_HOST flag
is set. For the other use cases, the vsock transport assignment logic is
not changed.
Changelog
v3 -> v4
* Update the "remote_flags" local variable type to reflect the change of
the "svm_flags" field to be 1 byte in size.
v2 -> v3
* Update bitwise check logic to not compare result to the flag value.
v1 -> v2
* Use bitwise operator to check the vsock flag.
* Use the updated "VMADDR_FLAG_TO_HOST" flag naming.
* Merge the checks for the g2h transport assignment in one "if" block.
Signed-off-by: Andra Paraschiv <andraprs@amazon.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The vsock flags can be set during the connect() setup logic, when
initializing the vsock address data structure variable. Then the vsock
transport is assigned, also considering this flags field.
The vsock transport is also assigned on the (listen) receive path. The
flags field needs to be set considering the use case.
Set the value of the vsock flags of the remote address to the one
targeted for packets forwarding to the host, if the following conditions
are met:
* The source CID of the packet is higher than VMADDR_CID_HOST.
* The destination CID of the packet is higher than VMADDR_CID_HOST.
Changelog
v3 -> v4
* No changes.
v2 -> v3
* No changes.
v1 -> v2
* Set the vsock flag on the receive path in the vsock transport
assignment logic.
* Use bitwise operator for the vsock flag setup.
* Use the updated "VMADDR_FLAG_TO_HOST" flag naming.
Signed-off-by: Andra Paraschiv <andraprs@amazon.com>
Reviewed-by: Stefano Garzarella <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>
Currently when an invalid ioctl command is used the error return
is -EINVAL. Fix this by returning the correct error -ENOIOCTLCMD.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When exercising the kernel with stress-ng with some ioctl tests the
"Unknown ioctl" error message is spamming the kernel log at a high
rate. Remove this message.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Stefano Garzarella <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>
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>
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>
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>
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 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>
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>
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_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>
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>
vm_sockets_get_local_cid() is only used in virtio_transport_common.c.
We can replace it calling the virtio_transport_get_ops() and
using the get_local_cid() callback registered by the transport.
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>
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>
Use 'skb_queue_purge()' instead of re-implementing it.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Many poll() handlers are lockless. Using skb_queue_empty_lockless()
instead of skb_queue_empty() is more appropriate.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Lockdep is unhappy if two locks from the same class are held.
Fix the below warning for hyperv and virtio sockets (vmci socket code
doesn't have the issue) by using lock_sock_nested() when __vsock_release()
is called recursively:
============================================
WARNING: possible recursive locking detected
5.3.0+ #1 Not tainted
--------------------------------------------
server/1795 is trying to acquire lock:
ffff8880c5158990 (sk_lock-AF_VSOCK){+.+.}, at: hvs_release+0x10/0x120 [hv_sock]
but task is already holding lock:
ffff8880c5158150 (sk_lock-AF_VSOCK){+.+.}, at: __vsock_release+0x2e/0xf0 [vsock]
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(sk_lock-AF_VSOCK);
lock(sk_lock-AF_VSOCK);
*** DEADLOCK ***
May be due to missing lock nesting notation
2 locks held by server/1795:
#0: ffff8880c5d05ff8 (&sb->s_type->i_mutex_key#10){+.+.}, at: __sock_release+0x2d/0xa0
#1: ffff8880c5158150 (sk_lock-AF_VSOCK){+.+.}, at: __vsock_release+0x2e/0xf0 [vsock]
stack backtrace:
CPU: 5 PID: 1795 Comm: server Not tainted 5.3.0+ #1
Call Trace:
dump_stack+0x67/0x90
__lock_acquire.cold.67+0xd2/0x20b
lock_acquire+0xb5/0x1c0
lock_sock_nested+0x6d/0x90
hvs_release+0x10/0x120 [hv_sock]
__vsock_release+0x24/0xf0 [vsock]
__vsock_release+0xa0/0xf0 [vsock]
vsock_release+0x12/0x30 [vsock]
__sock_release+0x37/0xa0
sock_close+0x14/0x20
__fput+0xc1/0x250
task_work_run+0x98/0xc0
do_exit+0x344/0xc60
do_group_exit+0x47/0xb0
get_signal+0x15c/0xc50
do_signal+0x30/0x720
exit_to_usermode_loop+0x50/0xa0
do_syscall_64+0x24e/0x270
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f4184e85f31
Tested-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Dexuan Cui <decui@microsoft.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current vsock code for removal of socket from the list is both
subject to race and inefficient. It takes the lock, checks whether
the socket is in the list, drops the lock and if the socket was on the
list, deletes it from the list. This is subject to race because as soon
as the lock is dropped once it is checked for presence, that condition
cannot be relied upon for any decision. It is also inefficient because
if the socket is present in the list, it takes the lock twice.
Signed-off-by: Sunil Muthuswamy <sunilmut@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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>
This is a cleanup to prepare for the addition of 64-bit time_t
in O_SNDTIMEO/O_RCVTIMEO. The existing compat handler seems
unnecessarily complex and error-prone, moving it all into the
main setsockopt()/getsockopt() implementation requires half
as much code and is easier to extend.
32-bit user space can now use old_timeval32 on both 32-bit
and 64-bit machines, while 64-bit code can use
__old_kernel_timeval.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The old code always starts from fixed port for VMADDR_PORT_ANY. Sometimes
when VMM crashed, there is still orphaned vsock which is waiting for
close timer, then it could cause connection time out for new started VM
if they are trying to connect to same port with same guest cid since the
new packets could hit that orphaned vsock. We could also fix this by doing
more in vhost_vsock_reset_orphans, but any way, it should be better to start
from a random local port instead of a fixed one.
Signed-off-by: Lepton Wu <ytht.net@gmail.com>
Reviewed-by: Jorgen Hansen <jhansen@vmware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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: d021c34405 ("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>
The poll() changes were not well thought out, and completely
unexplained. They also caused a huge performance regression, because
"->poll()" was no longer a trivial file operation that just called down
to the underlying file operations, but instead did at least two indirect
calls.
Indirect calls are sadly slow now with the Spectre mitigation, but the
performance problem could at least be largely mitigated by changing the
"->get_poll_head()" operation to just have a per-file-descriptor pointer
to the poll head instead. That gets rid of one of the new indirections.
But that doesn't fix the new complexity that is completely unwarranted
for the regular case. The (undocumented) reason for the poll() changes
was some alleged AIO poll race fixing, but we don't make the common case
slower and more complex for some uncommon special case, so this all
really needs way more explanations and most likely a fundamental
redesign.
[ This revert is a revert of about 30 different commits, not reverted
individually because that would just be unnecessarily messy - Linus ]
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit c1eef220c1 ("vsock: always call
vsock_init_tables()") introduced a module_init() function without a
corresponding module_exit() function.
Modules with an init function can only be removed if they also have an
exit function. Therefore the vsock module was considered "permanent"
and could not be removed.
This patch adds an empty module_exit() function so that "rmmod vsock"
works. No explicit cleanup is required because:
1. Transports call vsock_core_exit() upon exit and cannot be removed
while sockets are still alive.
2. vsock_diag.ko does not perform any action that requires cleanup by
vsock.ko.
Fixes: c1eef220c1 ("vsock: always call vsock_init_tables()")
Reported-by: Xiumei Mu <xmu@redhat.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Jorgen Hansen <jhansen@vmware.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Jorgen Hansen <jhansen@vmware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Changes since v1:
Added changes in these files:
drivers/infiniband/hw/usnic/usnic_transport.c
drivers/staging/lustre/lnet/lnet/lib-socket.c
drivers/target/iscsi/iscsi_target_login.c
drivers/vhost/net.c
fs/dlm/lowcomms.c
fs/ocfs2/cluster/tcp.c
security/tomoyo/network.c
Before:
All these functions either return a negative error indicator,
or store length of sockaddr into "int *socklen" parameter
and return zero on success.
"int *socklen" parameter is awkward. For example, if caller does not
care, it still needs to provide on-stack storage for the value
it does not need.
None of the many FOO_getname() functions of various protocols
ever used old value of *socklen. They always just overwrite it.
This change drops this parameter, and makes all these functions, on success,
return length of sockaddr. It's always >= 0 and can be differentiated
from an error.
Tests in callers are changed from "if (err)" to "if (err < 0)", where needed.
rpc_sockname() lost "int buflen" parameter, since its only use was
to be passed to kernel_getsockname() as &buflen and subsequently
not used in any way.
Userspace API is not changed.
text data bss dec hex filename
30108430 2633624 873672 33615726 200ef6e vmlinux.before.o
30108109 2633612 873672 33615393 200ee21 vmlinux.o
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: David S. Miller <davem@davemloft.net>
CC: linux-kernel@vger.kernel.org
CC: netdev@vger.kernel.org
CC: linux-bluetooth@vger.kernel.org
CC: linux-decnet-user@lists.sourceforge.net
CC: linux-wireless@vger.kernel.org
CC: linux-rdma@vger.kernel.org
CC: linux-sctp@vger.kernel.org
CC: linux-nfs@vger.kernel.org
CC: linux-x25@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
This is the mindless scripted replacement of kernel use of POLL*
variables as described by Al, done by this script:
for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do
L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'`
for f in $L; do sed -i "-es/^\([^\"]*\)\(\<POLL$V\>\)/\\1E\\2/" $f; done
done
with de-mangling cleanups yet to come.
NOTE! On almost all architectures, the EPOLL* constants have the same
values as the POLL* constants do. But they keyword here is "almost".
For various bad reasons they aren't the same, and epoll() doesn't
actually work quite correctly in some cases due to this on Sparc et al.
The next patch from Al will sort out the final differences, and we
should be all done.
Scripted-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull poll annotations from Al Viro:
"This introduces a __bitwise type for POLL### bitmap, and propagates
the annotations through the tree. Most of that stuff is as simple as
'make ->poll() instances return __poll_t and do the same to local
variables used to hold the future return value'.
Some of the obvious brainos found in process are fixed (e.g. POLLIN
misspelled as POLL_IN). At that point the amount of sparse warnings is
low and most of them are for genuine bugs - e.g. ->poll() instance
deciding to return -EINVAL instead of a bitmap. I hadn't touched those
in this series - it's large enough as it is.
Another problem it has caught was eventpoll() ABI mess; select.c and
eventpoll.c assumed that corresponding POLL### and EPOLL### were
equal. That's true for some, but not all of them - EPOLL### are
arch-independent, but POLL### are not.
The last commit in this series separates userland POLL### values from
the (now arch-independent) kernel-side ones, converting between them
in the few places where they are copied to/from userland. AFAICS, this
is the least disruptive fix preserving poll(2) ABI and making epoll()
work on all architectures.
As it is, it's simply broken on sparc - try to give it EPOLLWRNORM and
it will trigger only on what would've triggered EPOLLWRBAND on other
architectures. EPOLLWRBAND and EPOLLRDHUP, OTOH, are never triggered
at all on sparc. With this patch they should work consistently on all
architectures"
* 'misc.poll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (37 commits)
make kernel-side POLL... arch-independent
eventpoll: no need to mask the result of epi_item_poll() again
eventpoll: constify struct epoll_event pointers
debugging printk in sg_poll() uses %x to print POLL... bitmap
annotate poll(2) guts
9p: untangle ->poll() mess
->si_band gets POLL... bitmap stored into a user-visible long field
ring_buffer_poll_wait() return value used as return value of ->poll()
the rest of drivers/*: annotate ->poll() instances
media: annotate ->poll() instances
fs: annotate ->poll() instances
ipc, kernel, mm: annotate ->poll() instances
net: annotate ->poll() instances
apparmor: annotate ->poll() instances
tomoyo: annotate ->poll() instances
sound: annotate ->poll() instances
acpi: annotate ->poll() instances
crypto: annotate ->poll() instances
block: annotate ->poll() instances
x86: annotate ->poll() instances
...
select(2) with wfds but no rfds must return when the socket is shut down
by the peer. This way userspace notices socket activity and gets -EPIPE
from the next write(2).
Currently select(2) does not return for virtio-vsock when a SEND+RCV
shutdown packet is received. This is because vsock_poll() only sets
POLLOUT | POLLWRNORM for TCP_CLOSE, not the TCP_CLOSING state that the
socket is in when the shutdown is received.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Although CONFIG_VSOCKETS_DIAG depends on CONFIG_VSOCKETS,
vsock_init_tables() is not always called, it is called only
if other modules call its caller. Therefore if we only
enable CONFIG_VSOCKETS_DIAG, it would crash kernel on uninitialized
vsock_bind_table.
This patch fixes it by moving vsock_init_tables() to its own
module_init().
Fixes: 413a4317ac ("VSOCK: add sock_diag interface")
Reported-by: syzkaller bot
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Jorgen Hansen <jhansen@vmware.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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>
The vsock_diag.ko module will need to check socket table membership.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The socket table symbols need to be exported from vsock.ko so that the
vsock_diag.ko module will be able to traverse sockets.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As reported by Michal, vsock_stream_sendmsg() could still
sleep at vsock_stream_has_space() after prepare_to_wait():
vsock_stream_has_space
vmci_transport_stream_has_space
vmci_qpair_produce_free_space
qp_lock
qp_acquire_queue_mutex
mutex_lock
Just switch to the new wait API like we did for commit
d9dc8b0f8b ("net: fix sleeping for sk_wait_event()").
Reported-by: Michal Kubecek <mkubecek@suse.cz>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Jorgen Hansen <jhansen@vmware.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Claudio Imbrenda <imbrenda@linux.vnet.ibm.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Otherwise we'll leave the packets queued until releasing vsock device.
E.g., if guest is slow to start up, resulting ETIMEDOUT on connect, guest
will get the connect requests from failed host sockets.
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Jorgen Hansen <jhansen@vmware.com>
Signed-off-by: Peng Tao <bergwolf@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Lockdep issues a circular dependency warning when AFS issues an operation
through AF_RXRPC from a context in which the VFS/VM holds the mmap_sem.
The theory lockdep comes up with is as follows:
(1) If the pagefault handler decides it needs to read pages from AFS, it
calls AFS with mmap_sem held and AFS begins an AF_RXRPC call, but
creating a call requires the socket lock:
mmap_sem must be taken before sk_lock-AF_RXRPC
(2) afs_open_socket() opens an AF_RXRPC socket and binds it. rxrpc_bind()
binds the underlying UDP socket whilst holding its socket lock.
inet_bind() takes its own socket lock:
sk_lock-AF_RXRPC must be taken before sk_lock-AF_INET
(3) Reading from a TCP socket into a userspace buffer might cause a fault
and thus cause the kernel to take the mmap_sem, but the TCP socket is
locked whilst doing this:
sk_lock-AF_INET must be taken before mmap_sem
However, lockdep's theory is wrong in this instance because it deals only
with lock classes and not individual locks. The AF_INET lock in (2) isn't
really equivalent to the AF_INET lock in (3) as the former deals with a
socket entirely internal to the kernel that never sees userspace. This is
a limitation in the design of lockdep.
Fix the general case by:
(1) Double up all the locking keys used in sockets so that one set are
used if the socket is created by userspace and the other set is used
if the socket is created by the kernel.
(2) Store the kern parameter passed to sk_alloc() in a variable in the
sock struct (sk_kern_sock). This informs sock_lock_init(),
sock_init_data() and sk_clone_lock() as to the lock keys to be used.
Note that the child created by sk_clone_lock() inherits the parent's
kern setting.
(3) Add a 'kern' parameter to ->accept() that is analogous to the one
passed in to ->create() that distinguishes whether kernel_accept() or
sys_accept4() was the caller and can be passed to sk_alloc().
Note that a lot of accept functions merely dequeue an already
allocated socket. I haven't touched these as the new socket already
exists before we get the parameter.
Note also that there are a couple of places where I've made the accepted
socket unconditionally kernel-based:
irda_accept()
rds_rcp_accept_one()
tcp_accept_from_sock()
because they follow a sock_create_kern() and accept off of that.
Whilst creating this, I noticed that lustre and ocfs don't create sockets
through sock_create_kern() and thus they aren't marked as for-kernel,
though they appear to be internal. I wonder if these should do that so
that they use the new set of lock keys.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Andra Paraschiv