Commit Graph

255 Commits

Author SHA1 Message Date
Eiichi Tsukata c7cd82b905 vsock: prevent unnecessary refcnt inc for nonblocking connect
Currently vosck_connect() increments sock refcount for nonblocking
socket each time it's called, which can lead to memory leak if
it's called multiple times because connect timeout function decrements
sock refcount only once.

Fixes it by making vsock_connect() return -EALREADY immediately when
sock state is already SS_CONNECTING.

Fixes: d021c34405 ("VSOCK: Introduce VM Sockets")
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Eiichi Tsukata <eiichi.tsukata@nutanix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-10 14:36:11 +00:00
Richard Palethorpe 4c1e34c0db vsock: Enable y2038 safe timeval for timeout
Reuse the timeval compat code from core/sock to handle 32-bit and
64-bit timeval structures. Also introduce a new socket option define
to allow using y2038 safe timeval under 32-bit.

The existing behavior of sock_set_timeout and vsock's timeout setter
differ when the time value is out of bounds. vsocks current behavior
is retained at the expense of not being able to share the full
implementation.

This allows the LTP test vsock01 to pass under 32-bit compat mode.

Fixes: fe0c72f3db ("socket: move compat timeout handling into sock.c")
Signed-off-by: Richard Palethorpe <rpalethorpe@suse.com>
Cc: Richard Palethorpe <rpalethorpe@richiejp.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-08 16:21:53 +01:00
Richard Palethorpe 685c3f2fba vsock: Refactor vsock_*_getsockopt to resemble sock_getsockopt
In preparation for sharing the implementation of sock_get_timeout.

Signed-off-by: Richard Palethorpe <rpalethorpe@suse.com>
Cc: Richard Palethorpe <rpalethorpe@richiejp.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-08 16:21:53 +01:00
Arseny Krasnov 8fc92b7c15 af_vsock: rename variables in receive loop
Record is supported via MSG_EOR flag, while current logic operates
with message, so rename variables from 'record' to 'message'.

Signed-off-by: Arseny Krasnov <arseny.krasnov@kaspersky.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://lore.kernel.org/r/20210903123306.3273757-1-arseny.krasnov@kaspersky.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-09-06 02:25:16 -04:00
Arseny Krasnov 8d5ac871b5 virtio/vsock: support MSG_EOR bit processing
If packet has 'EOR' bit - set MSG_EOR in 'recvmsg()' flags.

Signed-off-by: Arseny Krasnov <arseny.krasnov@kaspersky.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://lore.kernel.org/r/20210903123251.3273639-1-arseny.krasnov@kaspersky.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-09-05 16:23:09 -04:00
Arseny Krasnov 9af8f10616 virtio/vsock: rename 'EOR' to 'EOM' bit.
This current implemented bit is used to mark end of messages
('EOM' - end of message), not records('EOR' - end of record).
Also rename 'record' to 'message' in implementation as it is
different things.

Signed-off-by: Arseny Krasnov <arseny.krasnov@kaspersky.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://lore.kernel.org/r/20210903123109.3273053-1-arseny.krasnov@kaspersky.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-09-05 16:23:08 -04:00
Longpeng(Mike) 49b0b6ffe2 vsock/virtio: avoid potential deadlock when vsock device remove
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>
2021-08-12 10:57:27 -07:00
Harshavardhan Unnibhavi e3ea110d6e VSOCK: handle VIRTIO_VSOCK_OP_CREDIT_REQUEST
The original implementation of the virtio-vsock driver does not
handle a VIRTIO_VSOCK_OP_CREDIT_REQUEST as required by the
virtio-vsock specification. The vsock device emulated by
vhost-vsock and the virtio-vsock driver never uses this request,
which was probably why nobody noticed it. However, another
implementation of the device may use this request type.

Hence, this commit introduces a way to handle an explicit credit
request by responding with a corresponding credit update as
required by the virtio-vsock specification.

Fixes: 06a8fc7836 ("VSOCK: Introduce virtio_vsock_common.ko")
Signed-off-by: Harshavardhan Unnibhavi <harshanavkis@gmail.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Link: https://lore.kernel.org/r/20210802173506.2383-1-harshanavkis@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-08-03 14:30:59 -07:00
Linus Torvalds dbe69e4337 Networking changes for 5.14.
Core:
 
  - BPF:
    - add syscall program type and libbpf support for generating
      instructions and bindings for in-kernel BPF loaders (BPF loaders
      for BPF), this is a stepping stone for signed BPF programs
    - infrastructure to migrate TCP child sockets from one listener
      to another in the same reuseport group/map to improve flexibility
      of service hand-off/restart
    - add broadcast support to XDP redirect
 
  - allow bypass of the lockless qdisc to improving performance
    (for pktgen: +23% with one thread, +44% with 2 threads)
 
  - add a simpler version of "DO_ONCE()" which does not require
    jump labels, intended for slow-path usage
 
  - virtio/vsock: introduce SOCK_SEQPACKET support
 
  - add getsocketopt to retrieve netns cookie
 
  - ip: treat lowest address of a IPv4 subnet as ordinary unicast address
        allowing reclaiming of precious IPv4 addresses
 
  - ipv6: use prandom_u32() for ID generation
 
  - ip: add support for more flexible field selection for hashing
        across multi-path routes (w/ offload to mlxsw)
 
  - icmp: add support for extended RFC 8335 PROBE (ping)
 
  - seg6: add support for SRv6 End.DT46 behavior
 
  - mptcp:
     - DSS checksum support (RFC 8684) to detect middlebox meddling
     - support Connection-time 'C' flag
     - time stamping support
 
  - sctp: packetization Layer Path MTU Discovery (RFC 8899)
 
  - xfrm: speed up state addition with seq set
 
  - WiFi:
     - hidden AP discovery on 6 GHz and other HE 6 GHz improvements
     - aggregation handling improvements for some drivers
     - minstrel improvements for no-ack frames
     - deferred rate control for TXQs to improve reaction times
     - switch from round robin to virtual time-based airtime scheduler
 
  - add trace points:
     - tcp checksum errors
     - openvswitch - action execution, upcalls
     - socket errors via sk_error_report
 
 Device APIs:
 
  - devlink: add rate API for hierarchical control of max egress rate
             of virtual devices (VFs, SFs etc.)
 
  - don't require RCU read lock to be held around BPF hooks
    in NAPI context
 
  - page_pool: generic buffer recycling
 
 New hardware/drivers:
 
  - mobile:
     - iosm: PCIe Driver for Intel M.2 Modem
     - support for Qualcomm MSM8998 (ipa)
 
  - WiFi: Qualcomm QCN9074 and WCN6855 PCI devices
 
  - sparx5: Microchip SparX-5 family of Enterprise Ethernet switches
 
  - Mellanox BlueField Gigabit Ethernet (control NIC of the DPU)
 
  - NXP SJA1110 Automotive Ethernet 10-port switch
 
  - Qualcomm QCA8327 switch support (qca8k)
 
  - Mikrotik 10/25G NIC (atl1c)
 
 Driver changes:
 
  - ACPI support for some MDIO, MAC and PHY devices from Marvell and NXP
    (our first foray into MAC/PHY description via ACPI)
 
  - HW timestamping (PTP) support: bnxt_en, ice, sja1105, hns3, tja11xx
 
  - Mellanox/Nvidia NIC (mlx5)
    - NIC VF offload of L2 bridging
    - support IRQ distribution to Sub-functions
 
  - Marvell (prestera):
     - add flower and match all
     - devlink trap
     - link aggregation
 
  - Netronome (nfp): connection tracking offload
 
  - Intel 1GE (igc): add AF_XDP support
 
  - Marvell DPU (octeontx2): ingress ratelimit offload
 
  - Google vNIC (gve): new ring/descriptor format support
 
  - Qualcomm mobile (rmnet & ipa): inline checksum offload support
 
  - MediaTek WiFi (mt76)
     - mt7915 MSI support
     - mt7915 Tx status reporting
     - mt7915 thermal sensors support
     - mt7921 decapsulation offload
     - mt7921 enable runtime pm and deep sleep
 
  - Realtek WiFi (rtw88)
     - beacon filter support
     - Tx antenna path diversity support
     - firmware crash information via devcoredump
 
  - Qualcomm 60GHz WiFi (wcn36xx)
     - Wake-on-WLAN support with magic packets and GTK rekeying
 
  - Micrel PHY (ksz886x/ksz8081): add cable test support
 
 Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'net-next-5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next

Pull networking updates from Jakub Kicinski:
 "Core:

   - BPF:
      - add syscall program type and libbpf support for generating
        instructions and bindings for in-kernel BPF loaders (BPF loaders
        for BPF), this is a stepping stone for signed BPF programs
      - infrastructure to migrate TCP child sockets from one listener to
        another in the same reuseport group/map to improve flexibility
        of service hand-off/restart
      - add broadcast support to XDP redirect

   - allow bypass of the lockless qdisc to improving performance (for
     pktgen: +23% with one thread, +44% with 2 threads)

   - add a simpler version of "DO_ONCE()" which does not require jump
     labels, intended for slow-path usage

   - virtio/vsock: introduce SOCK_SEQPACKET support

   - add getsocketopt to retrieve netns cookie

   - ip: treat lowest address of a IPv4 subnet as ordinary unicast
     address allowing reclaiming of precious IPv4 addresses

   - ipv6: use prandom_u32() for ID generation

   - ip: add support for more flexible field selection for hashing
     across multi-path routes (w/ offload to mlxsw)

   - icmp: add support for extended RFC 8335 PROBE (ping)

   - seg6: add support for SRv6 End.DT46 behavior

   - mptcp:
      - DSS checksum support (RFC 8684) to detect middlebox meddling
      - support Connection-time 'C' flag
      - time stamping support

   - sctp: packetization Layer Path MTU Discovery (RFC 8899)

   - xfrm: speed up state addition with seq set

   - WiFi:
      - hidden AP discovery on 6 GHz and other HE 6 GHz improvements
      - aggregation handling improvements for some drivers
      - minstrel improvements for no-ack frames
      - deferred rate control for TXQs to improve reaction times
      - switch from round robin to virtual time-based airtime scheduler

   - add trace points:
      - tcp checksum errors
      - openvswitch - action execution, upcalls
      - socket errors via sk_error_report

  Device APIs:

   - devlink: add rate API for hierarchical control of max egress rate
     of virtual devices (VFs, SFs etc.)

   - don't require RCU read lock to be held around BPF hooks in NAPI
     context

   - page_pool: generic buffer recycling

  New hardware/drivers:

   - mobile:
      - iosm: PCIe Driver for Intel M.2 Modem
      - support for Qualcomm MSM8998 (ipa)

   - WiFi: Qualcomm QCN9074 and WCN6855 PCI devices

   - sparx5: Microchip SparX-5 family of Enterprise Ethernet switches

   - Mellanox BlueField Gigabit Ethernet (control NIC of the DPU)

   - NXP SJA1110 Automotive Ethernet 10-port switch

   - Qualcomm QCA8327 switch support (qca8k)

   - Mikrotik 10/25G NIC (atl1c)

  Driver changes:

   - ACPI support for some MDIO, MAC and PHY devices from Marvell and
     NXP (our first foray into MAC/PHY description via ACPI)

   - HW timestamping (PTP) support: bnxt_en, ice, sja1105, hns3, tja11xx

   - Mellanox/Nvidia NIC (mlx5)
      - NIC VF offload of L2 bridging
      - support IRQ distribution to Sub-functions

   - Marvell (prestera):
      - add flower and match all
      - devlink trap
      - link aggregation

   - Netronome (nfp): connection tracking offload

   - Intel 1GE (igc): add AF_XDP support

   - Marvell DPU (octeontx2): ingress ratelimit offload

   - Google vNIC (gve): new ring/descriptor format support

   - Qualcomm mobile (rmnet & ipa): inline checksum offload support

   - MediaTek WiFi (mt76)
      - mt7915 MSI support
      - mt7915 Tx status reporting
      - mt7915 thermal sensors support
      - mt7921 decapsulation offload
      - mt7921 enable runtime pm and deep sleep

   - Realtek WiFi (rtw88)
      - beacon filter support
      - Tx antenna path diversity support
      - firmware crash information via devcoredump

   - Qualcomm WiFi (wcn36xx)
      - Wake-on-WLAN support with magic packets and GTK rekeying

   - Micrel PHY (ksz886x/ksz8081): add cable test support"

* tag 'net-next-5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2168 commits)
  tcp: change ICSK_CA_PRIV_SIZE definition
  tcp_yeah: check struct yeah size at compile time
  gve: DQO: Fix off by one in gve_rx_dqo()
  stmmac: intel: set PCI_D3hot in suspend
  stmmac: intel: Enable PHY WOL option in EHL
  net: stmmac: option to enable PHY WOL with PMT enabled
  net: say "local" instead of "static" addresses in ndo_dflt_fdb_{add,del}
  net: use netdev_info in ndo_dflt_fdb_{add,del}
  ptp: Set lookup cookie when creating a PTP PPS source.
  net: sock: add trace for socket errors
  net: sock: introduce sk_error_report
  net: dsa: replay the local bridge FDB entries pointing to the bridge dev too
  net: dsa: ensure during dsa_fdb_offload_notify that dev_hold and dev_put are on the same dev
  net: dsa: include fdb entries pointing to bridge in the host fdb list
  net: dsa: include bridge addresses which are local in the host fdb list
  net: dsa: sync static FDB entries on foreign interfaces to hardware
  net: dsa: install the host MDB and FDB entries in the master's RX filter
  net: dsa: reference count the FDB addresses at the cross-chip notifier level
  net: dsa: introduce a separate cross-chip notifier type for host FDBs
  net: dsa: reference count the MDB entries at the cross-chip notifier level
  ...
2021-06-30 15:51:09 -07:00
Jakub Kicinski b6df00789e Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Trivial conflict in net/netfilter/nf_tables_api.c.

Duplicate fix in tools/testing/selftests/net/devlink_port_split.py
- take the net-next version.

skmsg, and L4 bpf - keep the bpf code but remove the flags
and err params.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-06-29 15:45:27 -07:00
Alexander Aring e3ae2365ef 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>
2021-06-29 11:28:21 -07:00
Eric Dumazet 64295f0d01 virtio/vsock: avoid NULL deref in virtio_transport_seqpacket_allow()
Make sure the_virtio_vsock is not NULL before dereferencing it.

general protection fault, probably for non-canonical address 0xdffffc0000000071: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000388-0x000000000000038f]
CPU: 0 PID: 8452 Comm: syz-executor406 Not tainted 5.13.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:virtio_transport_seqpacket_allow+0xbf/0x210 net/vmw_vsock/virtio_transport.c:503
Code: e8 c6 d9 ab f8 84 db 0f 84 0f 01 00 00 e8 09 d3 ab f8 48 8d bd 88 03 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 04 02 84 c0 74 06 0f 8e 2a 01 00 00 44 0f b6 a5 88 03 00 00
RSP: 0018:ffffc90003757c18 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: 0000000000000001 RCX: 0000000000000000
RDX: 0000000000000071 RSI: ffffffff88c908e7 RDI: 0000000000000388
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff88c90a06 R11: 0000000000000000 R12: 0000000000000000
R13: ffffffff88c90840 R14: 0000000000000000 R15: 0000000000000001
FS:  0000000001bee300(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000082 CR3: 000000002847e000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 vsock_assign_transport+0x575/0x700 net/vmw_vsock/af_vsock.c:490
 vsock_connect+0x200/0xc00 net/vmw_vsock/af_vsock.c:1337
 __sys_connect_file+0x155/0x1a0 net/socket.c:1824
 __sys_connect+0x161/0x190 net/socket.c:1841
 __do_sys_connect net/socket.c:1851 [inline]
 __se_sys_connect net/socket.c:1848 [inline]
 __x64_sys_connect+0x6f/0xb0 net/socket.c:1848
 do_syscall_64+0x3a/0xb0 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x43ee69
Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd49e7c788 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: ffffffffffffffda RBX: 0000000000400488 RCX: 000000000043ee69
RDX: 0000000000000010 RSI: 0000000020000080 RDI: 0000000000000003
RBP: 0000000000402e50 R08: 0000000000000000 R09: 0000000000400488
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000402ee0
R13: 0000000000000000 R14: 00000000004ac018 R15: 0000000000400488

Fixes: 53efbba12c ("virtio/vsock: enable SEQPACKET for transport")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Arseny Krasnov <arseny.krasnov@kaspersky.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-22 09:49:37 -07:00
Longpeng(Mike) c7ff9cff70 vsock: notify server to shutdown when client has pending signal
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>
2021-06-21 14:43:28 -07:00
Stefano Garzarella 91aa49a8fa vsock/virtio: remove redundant `copy_failed` variable
When memcpy_to_msg() fails in virtio_transport_seqpacket_do_dequeue(),
we already set `dequeued_len` with the negative error value returned
by memcpy_to_msg().

So we can directly check `dequeued_len` value instead of using a
dedicated flag variable to skip the copy path for the rest of
fragments.

Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-18 12:59:53 -07:00
Stefano Garzarella 0de5b2e672 vsock: rename vsock_wait_data()
vsock_wait_data() is used only by STREAM and SEQPACKET sockets,
so let's rename it to vsock_connectible_wait_data(), using the same
nomenclature (connectible) used in other functions after the
introduction of SEQPACKET.

Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-18 12:59:53 -07:00
Stefano Garzarella cc97141afd vsock: rename vsock_has_data()
vsock_has_data() is used only by STREAM and SEQPACKET sockets,
so let's rename it to vsock_connectible_has_data(), using the same
nomenclature (connectible) used in other functions after the
introduction of SEQPACKET.

Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-18 12:59:53 -07:00
Arseny Krasnov 6e90a57795 vsock/loopback: enable SEQPACKET for transport
Add SEQPACKET ops for loopback transport and 'seqpacket_allow()'
callback.

Signed-off-by: Arseny Krasnov <arseny.krasnov@kaspersky.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-11 13:32:47 -07:00
Arseny Krasnov 53efbba12c virtio/vsock: enable SEQPACKET for transport
To make transport work with SOCK_SEQPACKET add two things:
1) SOCK_SEQPACKET ops for virtio transport and 'seqpacket_allow()'
   callback.
2) Handling of SEQPACKET bit: guest tries to negotiate it with vhost,
   so feature will be enabled only if bit is negotiated with device.

Signed-off-by: Arseny Krasnov <arseny.krasnov@kaspersky.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-11 13:32:47 -07:00
Arseny Krasnov 9ac841f5e9 virtio/vsock: rest of SOCK_SEQPACKET support
Small updates to make SOCK_SEQPACKET work:
1) Send SHUTDOWN on socket close for SEQPACKET type.
2) Set SEQPACKET packet type during send.
3) Set 'VIRTIO_VSOCK_SEQ_EOR' bit in flags for last
   packet of message.
4) Implement data check function for SEQPACKET.
5) Check for max datagram size.

Signed-off-by: Arseny Krasnov <arseny.krasnov@kaspersky.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-11 13:32:47 -07:00
Arseny Krasnov e4b1ef152f virtio/vsock: add SEQPACKET receive logic
Update current receive logic for SEQPACKET support: performs
check for packet and socket types on receive(if mismatch, then
reset connection). Increment EOR counter on receive. Also if
buffer of new packet was appended to buffer of last packet in
rx queue, update flags of last packet with flags of new packet.

Signed-off-by: Arseny Krasnov <arseny.krasnov@kaspersky.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-11 13:32:47 -07:00
Arseny Krasnov 44931195a5 virtio/vsock: dequeue callback for SOCK_SEQPACKET
Callback fetches RW packets from rx queue of socket until whole record
is copied(if user's buffer is full, user is not woken up). This is done
to not stall sender, because if we wake up user and it leaves syscall,
nobody will send credit update for rest of record, and sender will wait
for next enter of read syscall at receiver's side. So if user buffer is
full, we just send credit update and drop data.

Signed-off-by: Arseny Krasnov <arseny.krasnov@kaspersky.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-11 13:32:47 -07:00
Arseny Krasnov c10844c597 virtio/vsock: simplify credit update function API
This function is static and 'hdr' arg was always NULL.

Signed-off-by: Arseny Krasnov <arseny.krasnov@kaspersky.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-11 13:32:47 -07:00
Arseny Krasnov b93f8877c1 virtio/vsock: set packet's type in virtio_transport_send_pkt_info()
There is no need to set type of packet which differs from type
of socket, so move passing type of packet from 'info' structure
to  'virtio_transport_send_pkt_info()' function. Since at current
time only stream type is supported, set it directly in 'virtio_
transport_send_pkt_info()', so callers don't need to set it.

Signed-off-by: Arseny Krasnov <arseny.krasnov@kaspersky.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-11 13:32:47 -07:00
Arseny Krasnov 8cb48554ad af_vsock: update comments for stream sockets
Replace 'stream' to 'connection oriented' in comments as
SEQPACKET is also connection oriented.

Signed-off-by: Arseny Krasnov <arseny.krasnov@kaspersky.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-11 13:32:46 -07:00
Arseny Krasnov 0798e78b10 af_vsock: rest of SEQPACKET support
Add socket ops for SEQPACKET type and .seqpacket_allow() callback
to query transports if they support SEQPACKET. Also split path
for data check for STREAM and SEQPACKET branches.

Signed-off-by: Arseny Krasnov <arseny.krasnov@kaspersky.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-11 13:32:46 -07:00
Arseny Krasnov fbe70c4807 af_vsock: implement send logic for SEQPACKET
Update current stream enqueue function for SEQPACKET
support:
1) Call transport's seqpacket enqueue callback.
2) Return value from enqueue function is whole record length or error
   for SOCK_SEQPACKET.

Signed-off-by: Arseny Krasnov <arseny.krasnov@kaspersky.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-11 13:32:46 -07:00
Arseny Krasnov 9942c192b2 af_vsock: implement SEQPACKET receive loop
Add receive loop for SEQPACKET. It looks like receive loop for
STREAM, but there are differences:
1) It doesn't call notify callbacks.
2) It doesn't care about 'SO_SNDLOWAT' and 'SO_RCVLOWAT' values, because
   there is no sense for these values in SEQPACKET case.
3) It waits until whole record is received.
4) It processes and sets 'MSG_TRUNC' flag.

So to avoid extra conditions for two types of socket inside one loop, two
independent functions were created.

Signed-off-by: Arseny Krasnov <arseny.krasnov@kaspersky.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-11 13:32:46 -07:00
Arseny Krasnov 19c1b90e19 af_vsock: separate receive data loop
Some code in receive data loop could be shared between SEQPACKET
and STREAM sockets, while another part is type specific, so move STREAM
specific data receive logic to '__vsock_stream_recvmsg()' dedicated
function, while checks, that will be same for both STREAM and SEQPACKET
sockets, stays in 'vsock_connectible_recvmsg()'.

Signed-off-by: Arseny Krasnov <arseny.krasnov@kaspersky.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-11 13:32:46 -07:00
Arseny Krasnov b3f7fd5488 af_vsock: separate wait data loop
Wait loop for data could be shared between SEQPACKET and STREAM
sockets, so move it to dedicated function. While moving the code
around, let's update an old comment.

Signed-off-by: Arseny Krasnov <arseny.krasnov@kaspersky.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-11 13:32:46 -07:00
Arseny Krasnov a9e29e5511 af_vsock: update functions for connectible socket
Prepare af_vsock.c for SEQPACKET support: rename some functions such
as setsockopt(), getsockopt(), connect(), recvmsg(), sendmsg() in general
manner, because they are shared with stream sockets.

Signed-off-by: Arseny Krasnov <arseny.krasnov@kaspersky.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-11 13:32:46 -07:00
gushengxian 268551503d 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>
2021-06-10 13:43:12 -07:00
Andres Beltran adae1e931a Drivers: hv: vmbus: Copy packets sent by Hyper-V out of the ring buffer
Pointers to ring-buffer packets sent by Hyper-V are used within the
guest VM. Hyper-V can send packets with erroneous values or modify
packet fields after they are processed by the guest. To defend
against these scenarios, return a copy of the incoming VMBus packet
after validating its length and offset fields in hv_pkt_iter_first().
In this way, the packet can no longer be modified by the host.

Signed-off-by: Andres Beltran <lkmlabelt@gmail.com>
Co-developed-by: Andrea Parri (Microsoft) <parri.andrea@gmail.com>
Signed-off-by: Andrea Parri (Microsoft) <parri.andrea@gmail.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20210408161439.341988-1-parri.andrea@gmail.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
2021-05-14 17:37:46 +00:00
Yang Li f0a5818b47 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>
2021-04-30 15:00:59 -07:00
David S. Miller 6876a18d33 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-04-26 12:00:00 -07:00
Stefano Garzarella 8432b81149 vsock/virtio: free queued packets when closing socket
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>
2021-04-20 17:07:21 -07:00
Stefano Garzarella e16edc99d6 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 e8266c4c33
("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>
2021-04-19 14:30:23 -07:00
Lu Wei 9195f06b2d net: vsock: Fix a typo
Modify "occured" to "occurred" in net/vmw_vsock/af_vsock.c.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Lu Wei <luwei32@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-28 17:52:51 -07:00
David Brazdil 1f935e8e72 selinux: vsock: Set SID for socket returned by accept()
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>
2021-03-19 13:46:55 -07:00
Stefano Garzarella 1c5fae9c9a vsock: fix locking in vsock_shutdown()
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>
2021-02-09 15:31:22 -08:00
Stefano Garzarella ce7536bc73 vsock/virtio: update credit only if socket is not closed
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>
2021-02-08 13:27:46 -08:00
Norbert Slusarek 3d0bc44d39 net/vmw_vsock: improve locking in vsock_connect_timeout()
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>
2021-02-06 15:03:31 -08:00
Norbert Slusarek 5d1cbcc990 net/vmw_vsock: fix NULL pointer dereference
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>
2021-02-06 15:03:17 -08:00
Alexander Popov c518adafa3 vsock: fix the race conditions in multi-transport support
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>
2021-02-01 19:54:30 -08:00
Andra Paraschiv 7f816984f4 af_vsock: Assign the vsock transport considering the vsock address flags
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>
2020-12-14 19:33:39 -08:00
Andra Paraschiv 1b5f2ab98e af_vsock: Set VMADDR_FLAG_TO_HOST flag on the receive path
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>
2020-12-14 19:33:39 -08:00
Andra Paraschiv cada7ccd9d vsock_addr: Check for supported flag values
Check if the provided flags value from the vsock address data structure
includes the supported flags in the corresponding kernel version.

The first byte of the "svm_zero" field is used as "svm_flags", so add
the flags check instead.

Changelog

v3 -> v4

* New patch in v4.

Signed-off-by: Andra Paraschiv <andraprs@amazon.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-12-14 19:33:39 -08:00
Jakub Kicinski 5c39f26e67 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Trivial conflict in CAN, keep the net-next + the byteswap wrapper.

Conflicts:
	drivers/net/can/usb/gs_usb.c

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-27 18:25:27 -08:00
Stefano Garzarella 3fe356d58e vsock/virtio: discard packets only when socket is really closed
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>
2020-11-23 16:36:29 -08:00
Jakub Kicinski 56495a2442 Merge https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-19 19:08:46 -08:00
Stefano Garzarella 65b422d9b6 vsock: forward all packets to the host when no H2G is registered
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>
2020-11-14 11:33:39 -08:00