WARNING: DATA RACE
Write at 0x00c0010bc6d0 by goroutine 763:
  gvisor.dev/gvisor/pkg/tcpip/transport/udp.(*endpoint).Connect()
      pkg/tcpip/transport/udp/endpoint.go:1053 +0x46a
  gvisor.dev/gvisor/pkg/sentry/socket/netstack.(*SocketOperations).Connect()
      pkg/sentry/socket/netstack/netstack.go:698 +0x4c5
  gvisor.dev/gvisor/pkg/sentry/syscalls/linux.Connect()
      pkg/sentry/syscalls/linux/sys_socket.go:280 +0x251
  gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).executeSyscall()
      pkg/sentry/kernel/task_syscall.go:170 +0x44d
  gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallInvoke()
      pkg/sentry/kernel/task_syscall.go:291 +0xb4
  gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallEnter()
      pkg/sentry/kernel/task_syscall.go:252 +0x109
  gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscall()
      pkg/sentry/kernel/task_syscall.go:227 +0x1b3
  gvisor.dev/gvisor/pkg/sentry/kernel.(*runApp).execute()
      pkg/sentry/kernel/task_run.go:232 +0x1aaa
  gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).run()
      pkg/sentry/kernel/task_run.go:92 +0x320

Previous read at 0x00c0010bc6d0 by goroutine 781:
DIAGNOSIS:
I0302 22:45:12.713025   10346 main.go:305] ***************************
I0302 22:45:12.713338   10346 main.go:306] Args: [/syzkaller/managers/ptrace-proxy-sandbox-race/current/image -root /syzkaller/managers/ptrace-proxy-sandbox-race/workdir/gvisor_root -watchdog-action=panic -network=none -debug -alsologtostderr -platform=ptrace -file-access=shared -network=sandbox -TESTONLY-unsafe-nonroot debug -stacks --ps ci-gvisor-ptrace-proxy-sandbox-race-0]
I0302 22:45:12.713568   10346 main.go:307] Version release-20200219.0-72-gce4d1e45bb88
I0302 22:45:12.713683   10346 main.go:308] PID: 10346
I0302 22:45:12.713839   10346 main.go:309] UID: 0, GID: 0
I0302 22:45:12.713980   10346 main.go:310] Configuration:
I0302 22:45:12.714082   10346 main.go:311] 		RootDir: /syzkaller/managers/ptrace-proxy-sandbox-race/workdir/gvisor_root
I0302 22:45:12.714211   10346 main.go:312] 		Platform: ptrace
I0302 22:45:12.714303   10346 main.go:313] 		FileAccess: shared, overlay: false
I0302 22:45:12.714442   10346 main.go:314] 		Network: sandbox, logging: false
I0302 22:45:12.714554   10346 main.go:315] 		Strace: false, max size: 1024, syscalls: []
I0302 22:45:12.714625   10346 main.go:316] ***************************
W0302 22:45:12.714714   10346 main.go:321] Block the TERM signal. This is only safe in tests!
D0302 22:45:12.714920   10346 container.go:159] Load container "/syzkaller/managers/ptrace-proxy-sandbox-race/workdir/gvisor_root" "ci-gvisor-ptrace-proxy-sandbox-race-0"
D0302 22:45:12.725211   10346 container.go:592] Signal container "ci-gvisor-ptrace-proxy-sandbox-race-0": signal 0
D0302 22:45:12.725467   10346 sandbox.go:806] Signal sandbox "ci-gvisor-ptrace-proxy-sandbox-race-0"
D0302 22:45:12.725599   10346 sandbox.go:318] Connecting to sandbox "ci-gvisor-ptrace-proxy-sandbox-race-0"
D0302 22:45:12.726201   10346 urpc.go:534] urpc: successfully marshalled 117 bytes.
I0302 22:45:12.951693   10346 debug.go:122] Found sandbox "ci-gvisor-ptrace-proxy-sandbox-race-0", PID: 6457
I0302 22:45:12.951851   10346 debug.go:131] Retrieving sandbox stacks
D0302 22:45:12.952001   10346 sandbox.go:924] Stacks sandbox "ci-gvisor-ptrace-proxy-sandbox-race-0"
D0302 22:45:12.952179   10346 sandbox.go:318] Connecting to sandbox "ci-gvisor-ptrace-proxy-sandbox-race-0"
W0302 22:45:12.952383   10346 error.go:48] FATAL ERROR: retrieving stacks: connecting to control server at PID 6457: connection refused
retrieving stacks: connecting to control server at PID 6457: connection refused
W0302 22:45:12.952704   10346 main.go:338] Failure to execute command, err: 1