linux/net
Stefano Garzarella 3f74957fcb vsock: fix potential deadlock in transport->release()
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>
2020-02-27 12:03:56 -08:00
..
6lowpan
9p
802
8021q Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-01-09 12:13:43 -08:00
appletalk
atm proc: convert everything to "struct proc_ops" 2020-02-04 03:05:26 +00:00
ax25 net: Make sock protocol value checks more specific 2020-01-09 18:41:40 -08:00
batman-adv Merge ra.kernel.org:/pub/scm/linux/kernel/git/netdev/net 2020-01-19 22:10:04 +01:00
bluetooth Bluetooth: Fix race condition in hci_release_sock() 2020-01-26 10:34:17 +02:00
bpf bpf: Allow to change skb mark in test_run 2019-12-18 17:05:58 -08:00
bpfilter kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
bridge net: bridge: fix stale eth hdr pointer in br_dev_xmit 2020-02-24 11:11:19 -08:00
caif caif_usb: fix spelling mistake "to" -> "too" 2020-01-24 08:12:06 +01:00
can
ceph Merge branch 'merge.nfs-fs_parse.1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-02-08 13:26:41 -08:00
core net: core: devlink.c: Use built-in RCU list checking 2020-02-26 16:59:18 -08:00
dcb
dccp
decnet net: Make sock protocol value checks more specific 2020-01-09 18:41:40 -08:00
dns_resolver
dsa net: dsa: tag_ar9331: Make sure there is headroom for tag 2020-02-14 07:34:51 -08:00
ethernet net: remove eth_change_mtu 2020-01-27 11:09:31 +01:00
ethtool ethtool: limit bitset size 2020-02-26 11:27:31 -08:00
hsr net: hsr: Pass lockdep expression to RCU lists 2020-02-19 10:55:42 -08:00
ieee802154
ife
ipv4 tcp: fix TFO SYNACK undo to avoid double-timestamp-undo 2020-02-23 17:23:35 -08:00
ipv6 ipv6: restrict IPV6_ADDRFORM operation 2020-02-26 20:20:58 -08:00
iucv
kcm
key
l2tp l2tp: Allow duplicate session creation with UDP 2020-02-04 12:35:49 +01:00
l3mdev
lapb
llc llc2: Fix return statement of llc_stat_ev_rx_null_dsap_xid_c (and _test_c) 2019-12-20 21:19:36 -08:00
mac80211 mac80211: rx: avoid RCU list traversal under mutex 2020-02-24 10:42:38 +01:00
mac802154
mpls
mptcp mptcp: add dummy icsk_sync_mss() 2020-02-26 20:49:50 -08:00
ncsi net/ncsi: Support for multi host mellanox card 2020-01-09 18:36:22 -08:00
netfilter netfilter: xt_hashlimit: unregister proc file before releasing mutex 2020-02-26 23:25:07 +01:00
netlabel netlabel_domainhash.c: Use built-in RCU list checking 2020-02-18 12:44:23 -08:00
netlink net: genetlink: return the error code when attribute parsing fails. 2020-02-22 21:58:33 -08:00
netrom
nfc net: nfc: nci: fix a possible sleep-in-atomic-context bug in nci_uart_tty_receive() 2019-12-18 11:57:33 -08:00
nsh
openvswitch openvswitch: Distribute switch variables for initialization 2020-02-20 10:00:19 -08:00
packet y2038: core, driver and file system changes 2020-01-29 14:55:47 -08:00
phonet net: Remove redundant BUG_ON() check in phonet_pernet 2020-01-03 12:25:50 -08:00
psample
qrtr net: qrtr: Remove receive worker 2020-01-14 18:36:42 -08:00
rds net/rds: Track user mapped pages through special API 2020-02-16 18:37:09 -08:00
rfkill
rose Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-01-26 10:40:21 +01:00
rxrpc rxrpc: Fix call RCU cleanup using non-bh-safe locks 2020-02-07 11:20:57 +01:00
sched sched: act: count in the size of action flags bitfield 2020-02-26 17:10:44 -08:00
sctp sctp: move the format error check out of __sctp_sf_do_9_1_abort 2020-02-17 21:56:03 -08:00
smc net/smc: check for valid ib_client_data 2020-02-26 20:56:25 -08:00
strparser
sunrpc xprtrdma: Fix DMA scatter-gather list mapping imbalance 2020-02-13 15:35:33 -05:00
switchdev
tipc tipc: fix successful connect() but timed out 2020-02-10 10:23:00 +01:00
tls net/tls: Fix to avoid gettig invalid tls record 2020-02-19 16:32:06 -08:00
unix unix: It's CONFIG_PROC_FS not CONFIG_PROCFS 2020-02-27 11:52:35 -08:00
vmw_vsock vsock: fix potential deadlock in transport->release() 2020-02-27 12:03:56 -08:00
wimax
wireless nl80211: explicitly include if_vlan.h 2020-02-24 10:41:13 +01:00
x25 net/x25: fix nonblocking connect 2020-01-09 18:39:33 -08:00
xdp xsk: Publish global consumer pointers when NAPI is finished 2020-02-11 15:51:11 +01:00
xfrm xfrm: interface: use icmp_ndo_send helper 2020-02-13 14:19:00 -08:00
compat.c
Kconfig net: disable BRIDGE_NETFILTER by default 2020-02-20 15:02:02 -08:00
Makefile mptcp: Add MPTCP socket stubs 2020-01-24 13:44:07 +01:00
socket.c socket: fix unused-function warning 2020-01-08 15:02:21 -08:00
sysctl_net.c