WARNING: DATA RACE
Write at 0x00c0002da910 by goroutine 162:
  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 +0x455
  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 +0x1aaf
  gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).run()
      pkg/sentry/kernel/task_run.go:92 +0x308

Previous read at 0x00c0002da910 by goroutine 731:
DIAGNOSIS:
I0228 17:50:37.843846   61477 main.go:296] ***************************
I0228 17:50:37.844029   61477 main.go:297] 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]
I0228 17:50:37.844326   61477 main.go:298] Version release-20200219.0-63-gc96bb4d2ebc6
I0228 17:50:37.844551   61477 main.go:299] PID: 61477
I0228 17:50:37.844697   61477 main.go:300] UID: 0, GID: 0
I0228 17:50:37.844861   61477 main.go:301] Configuration:
I0228 17:50:37.844977   61477 main.go:302] 		RootDir: /syzkaller/managers/ptrace-proxy-sandbox-race/workdir/gvisor_root
I0228 17:50:37.845089   61477 main.go:303] 		Platform: ptrace
I0228 17:50:37.845165   61477 main.go:304] 		FileAccess: shared, overlay: false
I0228 17:50:37.845271   61477 main.go:305] 		Network: sandbox, logging: false
I0228 17:50:37.845356   61477 main.go:306] 		Strace: false, max size: 1024, syscalls: []
I0228 17:50:37.845487   61477 main.go:307] ***************************
W0228 17:50:37.845546   61477 main.go:312] Block the TERM signal. This is only safe in tests!
D0228 17:50:37.845745   61477 container.go:159] Load container "/syzkaller/managers/ptrace-proxy-sandbox-race/workdir/gvisor_root" "ci-gvisor-ptrace-proxy-sandbox-race-0"
D0228 17:50:37.853038   61477 container.go:592] Signal container "ci-gvisor-ptrace-proxy-sandbox-race-0": signal 0
D0228 17:50:37.853198   61477 sandbox.go:788] Signal sandbox "ci-gvisor-ptrace-proxy-sandbox-race-0"
D0228 17:50:37.853297   61477 sandbox.go:318] Connecting to sandbox "ci-gvisor-ptrace-proxy-sandbox-race-0"
D0228 17:50:37.853737   61477 urpc.go:534] urpc: successfully marshalled 117 bytes.
I0228 17:50:38.012254   61477 debug.go:122] Found sandbox "ci-gvisor-ptrace-proxy-sandbox-race-0", PID: 56181
I0228 17:50:38.012529   61477 debug.go:131] Retrieving sandbox stacks
D0228 17:50:38.012614   61477 sandbox.go:906] Stacks sandbox "ci-gvisor-ptrace-proxy-sandbox-race-0"
D0228 17:50:38.012709   61477 sandbox.go:318] Connecting to sandbox "ci-gvisor-ptrace-proxy-sandbox-race-0"
W0228 17:50:38.012869   61477 error.go:48] FATAL ERROR: retrieving stacks: connecting to control server at PID 56181: connection refused
retrieving stacks: connecting to control server at PID 56181: connection refused
W0228 17:50:38.013145   61477 main.go:329] Failure to execute command, err: 1