linux-stable.git/net/vmw_vsock, branch v5.9.2

vsock: fix potential null pointer dereference in vsock_poll()

2020-08-12T19:56:06+00:00

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: c0cfa2d8a788 ("vsock: add multi-transports support")
Reported-and-tested-by: syzbot+a61bac2fcc1a7c6623fe@syzkaller.appspotmail.com
Signed-off-by: Stefano Garzarella 
Reviewed-by: Jorgen Hansen 
Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2020-07-26T00:49:04+00:00

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 efc6b6f6c3113e8b203b9debfb72d81e0f3dcace
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

net: pass a sockptr_t into ->setsockopt

2020-07-24T22:41:54+00:00

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 
Acked-by: Stefan Schmidt  [ieee802154]
Acked-by: Matthieu Baerts 
Signed-off-by: David S. Miller

net: make ->{get,set}sockopt in proto_ops optional

2020-07-20T01:16:41+00:00

Just check for a NULL method instead of wiring up
sock_no_{get,set}sockopt.

Signed-off-by: Christoph Hellwig 
Acked-by: Marc Kleine-Budde 
Signed-off-by: David S. Miller

vsock/virtio: annotate 'the_virtio_vsock' RCU pointer

2020-07-16T00:47:15+00:00

Commit 0deab087b16a ("vsock/virtio: use RCU to avoid use-after-free
on the_virtio_vsock") starts to use RCU to protect 'the_virtio_vsock'
pointer, but we forgot to annotate it.

This patch adds the annotation to fix the following sparse errors:

    net/vmw_vsock/virtio_transport.c:73:17: error: incompatible types in comparison expression (different address spaces):
    net/vmw_vsock/virtio_transport.c:73:17:    struct virtio_vsock [noderef] __rcu *
    net/vmw_vsock/virtio_transport.c:73:17:    struct virtio_vsock *
    net/vmw_vsock/virtio_transport.c:171:17: error: incompatible types in comparison expression (different address spaces):
    net/vmw_vsock/virtio_transport.c:171:17:    struct virtio_vsock [noderef] __rcu *
    net/vmw_vsock/virtio_transport.c:171:17:    struct virtio_vsock *
    net/vmw_vsock/virtio_transport.c:207:17: error: incompatible types in comparison expression (different address spaces):
    net/vmw_vsock/virtio_transport.c:207:17:    struct virtio_vsock [noderef] __rcu *
    net/vmw_vsock/virtio_transport.c:207:17:    struct virtio_vsock *
    net/vmw_vsock/virtio_transport.c:561:13: error: incompatible types in comparison expression (different address spaces):
    net/vmw_vsock/virtio_transport.c:561:13:    struct virtio_vsock [noderef] __rcu *
    net/vmw_vsock/virtio_transport.c:561:13:    struct virtio_vsock *
    net/vmw_vsock/virtio_transport.c:612:9: error: incompatible types in comparison expression (different address spaces):
    net/vmw_vsock/virtio_transport.c:612:9:    struct virtio_vsock [noderef] __rcu *
    net/vmw_vsock/virtio_transport.c:612:9:    struct virtio_vsock *
    net/vmw_vsock/virtio_transport.c:631:9: error: incompatible types in comparison expression (different address spaces):
    net/vmw_vsock/virtio_transport.c:631:9:    struct virtio_vsock [noderef] __rcu *
    net/vmw_vsock/virtio_transport.c:631:9:    struct virtio_vsock *

Fixes: 0deab087b16a ("vsock/virtio: use RCU to avoid use-after-free on the_virtio_vsock")
Reported-by: Michael S. Tsirkin 
Signed-off-by: Stefano Garzarella 
Reviewed-by: Stefan Hajnoczi 
Acked-by: Michael S. Tsirkin 
Signed-off-by: Jakub Kicinski

vsock/vmci: make vmci_vsock_transport_cb() static

2020-06-05T20:18:26+00:00

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

Fixes: b1bba80a4376 ("vsock/vmci: register vmci_transport only when VMCI guest/host are active")
Reported-by: kernel test robot 
Signed-off-by: Stefano Garzarella 
Signed-off-by: David S. Miller

virtio_vsock: Fix race condition in virtio_transport_recv_pkt

2020-05-31T00:44:01+00:00

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 
Reviewed-by: Stefano Garzarella 
Signed-off-by: David S. Miller

vsock: fix timeout in vsock_accept()

2020-05-27T18:20:23+00:00

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: d021c344051a ("VSOCK: Introduce VM Sockets")
Signed-off-by: Stefano Garzarella 
Reviewed-by: Jorgen Hansen 
Signed-off-by: David S. Miller

vsock/virtio: fix multiple packet delivery to monitoring devices

2020-04-27T17:18:01+00:00

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 
Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2020-02-28T02:31:39+00:00

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