linux-stable.git/net/vmw_vsock, branch v5.3.14

vhost/vsock: split packets to send using multiple buffers

2019-11-29T09:07:41+00:00

commit 6dbd3e66e7785a2f055bf84d98de9b8fd31ff3f5 upstream.

If the packets to sent to the guest are bigger than the buffer
available, we can split them, using multiple buffers and fixing
the length in the packet header.
This is safe since virtio-vsock supports only stream sockets.

Signed-off-by: Stefano Garzarella 
Reviewed-by: Stefan Hajnoczi 
Acked-by: Michael S. Tsirkin 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

vsock/virtio: fix sock refcnt holding during the shutdown

2019-11-12T18:26:51+00:00

[ Upstream commit ad8a7220355d39cddce8eac1cea9677333e8b821 ]

The "42f5cda5eaf4" commit rightly set SOCK_DONE on peer shutdown,
but there is an issue if we receive the SHUTDOWN(RDWR) while the
virtio_transport_close_timeout() is scheduled.
In this case, when the timeout fires, the SOCK_DONE is already
set and the virtio_transport_close_timeout() will not call
virtio_transport_reset() and virtio_transport_do_close().
This causes that both sockets remain open and will never be released,
preventing the unloading of [virtio|vhost]_transport modules.

This patch fixes this issue, calling virtio_transport_reset() and
virtio_transport_do_close() when we receive the SHUTDOWN(RDWR)
and there is nothing left to read.

Fixes: 42f5cda5eaf4 ("vsock/virtio: set SOCK_DONE on peer shutdown")
Cc: Stephen Barber 
Signed-off-by: Stefano Garzarella 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: use skb_queue_empty_lockless() in poll() handlers

2019-11-10T10:34:44+00:00

[ Upstream commit 3ef7cf57c72f32f61e97f8fa401bc39ea1f1a5d4 ]

Many poll() handlers are lockless. Using skb_queue_empty_lockless()
instead of skb_queue_empty() is more appropriate.

Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

vsock: Fix a lockdep warning in __vsock_release()

2019-10-07T17:01:50+00:00

[ Upstream commit 0d9138ffac24cf8b75366ede3a68c951e6dcc575 ]

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 
Signed-off-by: Dexuan Cui 
Reviewed-by: Stefano Garzarella 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

hv_sock: Fix hang when a connection is closed

2019-08-03T00:26:27+00:00

There is a race condition for an established connection that is being closed
by the guest: the refcnt is 4 at the end of hvs_release() (Note: here the
'remove_sock' is false):

1 for the initial value;
1 for the sk being in the bound list;
1 for the sk being in the connected list;
1 for the delayed close_work.

After hvs_release() finishes, __vsock_release() -> sock_put(sk) *may*
decrease the refcnt to 3.

Concurrently, hvs_close_connection() runs in another thread:
  calls vsock_remove_sock() to decrease the refcnt by 2;
  call sock_put() to decrease the refcnt to 0, and free the sk;
  next, the "release_sock(sk)" may hang due to use-after-free.

In the above, after hvs_release() finishes, if hvs_close_connection() runs
faster than "__vsock_release() -> sock_put(sk)", then there is not any issue,
because at the beginning of hvs_close_connection(), the refcnt is still 4.

The issue can be resolved if an extra reference is taken when the
connection is established.

Fixes: a9eeb998c28d ("hv_sock: Add support for delayed close")
Signed-off-by: Dexuan Cui 
Reviewed-by: Sunil Muthuswamy 
Signed-off-by: David S. Miller

vsock/virtio: fix flush of works during the .remove()

2019-07-08T22:35:17+00:00

This patch moves the flush of works after vdev->config->del_vqs(vdev),
because we need to be sure that no workers run before to free the
'vsock' object.

Since we stopped the workers using the [tx|rx|event]_run flags,
we are sure no one is accessing the device while we are calling
vdev->config->reset(vdev), so we can safely move the workers' flush.

Before the vdev->config->del_vqs(vdev), workers can be scheduled
by VQ callbacks, so we must flush them after del_vqs(), to avoid
use-after-free of 'vsock' object.

Suggested-by: Michael S. Tsirkin 
Signed-off-by: Stefano Garzarella 
Signed-off-by: David S. Miller

vsock/virtio: stop workers during the .remove()

2019-07-08T22:35:17+00:00

Before to call vdev->config->reset(vdev) we need to be sure that
no one is accessing the device, for this reason, we add new variables
in the struct virtio_vsock to stop the workers during the .remove().

This patch also add few comments before vdev->config->reset(vdev)
and vdev->config->del_vqs(vdev).

Suggested-by: Stefan Hajnoczi 
Suggested-by: Michael S. Tsirkin 
Signed-off-by: Stefano Garzarella 
Signed-off-by: David S. Miller

vsock/virtio: use RCU to avoid use-after-free on the_virtio_vsock

2019-07-08T22:35:17+00:00

Some callbacks used by the upper layers can run while we are in the
.remove(). A potential use-after-free can happen, because we free
the_virtio_vsock without knowing if the callbacks are over or not.

To solve this issue we move the assignment of the_virtio_vsock at the
end of .probe(), when we finished all the initialization, and at the
beginning of .remove(), before to release resources.
For the same reason, we do the same also for the vdev->priv.

We use RCU to be sure that all callbacks that use the_virtio_vsock
ended before freeing it. This is not required for callbacks that
use vdev->priv, because after the vdev->config->del_vqs() we are sure
that they are ended and will no longer be invoked.

We also take the mutex during the .remove() to avoid that .probe() can
run while we are resetting the device.

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

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

2019-06-22T12:59:24+00:00

Minor SPDX change conflict.

Signed-off-by: David S. Miller

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

2019-06-22T05:23:35+00:00

Pull networking fixes from David Miller:

 1) Fix leak of unqueued fragments in ipv6 nf_defrag, from Guillaume
    Nault.

 2) Don't access the DDM interface unless the transceiver implements it
    in bnx2x, from Mauro S. M. Rodrigues.

 3) Don't double fetch 'len' from userspace in sock_getsockopt(), from
    JingYi Hou.

 4) Sign extension overflow in lio_core, from Colin Ian King.

 5) Various netem bug fixes wrt. corrupted packets from Jakub Kicinski.

 6) Fix epollout hang in hvsock, from Sunil Muthuswamy.

 7) Fix regression in default fib6_type, from David Ahern.

 8) Handle memory limits in tcp_fragment more appropriately, from Eric
    Dumazet.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (24 commits)
  tcp: refine memory limit test in tcp_fragment()
  inet: clear num_timeout reqsk_alloc()
  net: mvpp2: debugfs: Add pmap to fs dump
  ipv6: Default fib6_type to RTN_UNICAST when not set
  net: hns3: Fix inconsistent indenting
  net/af_iucv: always register net_device notifier
  net/af_iucv: build proper skbs for HiperTransport
  net/af_iucv: remove GFP_DMA restriction for HiperTransport
  net: dsa: mv88e6xxx: fix shift of FID bits in mv88e6185_g1_vtu_loadpurge()
  hvsock: fix epollout hang from race condition
  net/udp_gso: Allow TX timestamp with UDP GSO
  net: netem: fix use after free and double free with packet corruption
  net: netem: fix backlog accounting for corrupted GSO frames
  net: lio_core: fix potential sign-extension overflow on large shift
  tipc: pass tunnel dev as NULL to udp_tunnel(6)_xmit_skb
  ip6_tunnel: allow not to count pkts on tstats by passing dev as NULL
  ip_tunnel: allow not to count pkts on tstats by setting skb's dev to NULL
  tun: wake up waitqueues after IFF_UP is set
  net: remove duplicate fetch in sock_getsockopt
  tipc: fix issues with early FAILOVER_MSG from peer
  ...