WARNING: DATA RACE
Write at 0x00c000736228 by goroutine 261:
  gvisor.dev/gvisor/pkg/sentry/socket/netstack.(*SocketOperations).fetchReadView()
      pkg/sentry/socket/netstack/netstack.go:418 +0x85
  gvisor.dev/gvisor/pkg/sentry/socket/netstack.(*SocketOperations).nonBlockingRead()
      pkg/sentry/socket/netstack/netstack.go:2388 +0x169
  gvisor.dev/gvisor/pkg/sentry/socket/netstack.(*SocketOperations).RecvMsg()
      pkg/sentry/socket/netstack/netstack.go:2507 +0x1ad
  gvisor.dev/gvisor/pkg/sentry/syscalls/linux.recvSingleMsg()
      pkg/sentry/syscalls/linux/sys_socket.go:761 +0xaed
  gvisor.dev/gvisor/pkg/sentry/syscalls/linux.RecvMsg()
      pkg/sentry/syscalls/linux/sys_socket.go:646 +0x291
  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 0x00c000736228 by goroutine 367:
  gvisor.dev/gvisor/pkg/sentry/socket/netstack.(*SocketOperations).Ioctl()
      pkg/sentry/socket/netstack/netstack.go:2666 +0x533
DIAGNOSIS:
I0228 23:11:33.816745   47021 main.go:296] ***************************
I0228 23:11:33.816873   47021 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-2]
I0228 23:11:33.817030   47021 main.go:298] Version release-20200219.0-63-gc96bb4d2ebc6
I0228 23:11:33.817092   47021 main.go:299] PID: 47021
I0228 23:11:33.817161   47021 main.go:300] UID: 0, GID: 0
I0228 23:11:33.817224   47021 main.go:301] Configuration:
I0228 23:11:33.817286   47021 main.go:302] 		RootDir: /syzkaller/managers/ptrace-proxy-sandbox-race/workdir/gvisor_root
I0228 23:11:33.817346   47021 main.go:303] 		Platform: ptrace
I0228 23:11:33.817406   47021 main.go:304] 		FileAccess: shared, overlay: false
I0228 23:11:33.817480   47021 main.go:305] 		Network: sandbox, logging: false
I0228 23:11:33.817573   47021 main.go:306] 		Strace: false, max size: 1024, syscalls: []
I0228 23:11:33.817635   47021 main.go:307] ***************************
W0228 23:11:33.817701   47021 main.go:312] Block the TERM signal. This is only safe in tests!
D0228 23:11:33.817832   47021 container.go:159] Load container "/syzkaller/managers/ptrace-proxy-sandbox-race/workdir/gvisor_root" "ci-gvisor-ptrace-proxy-sandbox-race-2"
D0228 23:11:33.823511   47021 container.go:592] Signal container "ci-gvisor-ptrace-proxy-sandbox-race-2": signal 0
D0228 23:11:33.823637   47021 sandbox.go:788] Signal sandbox "ci-gvisor-ptrace-proxy-sandbox-race-2"
D0228 23:11:33.823721   47021 sandbox.go:318] Connecting to sandbox "ci-gvisor-ptrace-proxy-sandbox-race-2"
D0228 23:11:33.824097   47021 urpc.go:534] urpc: successfully marshalled 117 bytes.
I0228 23:11:33.876442   47021 debug.go:122] Found sandbox "ci-gvisor-ptrace-proxy-sandbox-race-2", PID: 36044
I0228 23:11:33.876605   47021 debug.go:131] Retrieving sandbox stacks
D0228 23:11:33.876678   47021 sandbox.go:906] Stacks sandbox "ci-gvisor-ptrace-proxy-sandbox-race-2"
D0228 23:11:33.876782   47021 sandbox.go:318] Connecting to sandbox "ci-gvisor-ptrace-proxy-sandbox-race-2"
W0228 23:11:33.876926   47021 error.go:48] FATAL ERROR: retrieving stacks: connecting to control server at PID 36044: connection refused
retrieving stacks: connecting to control server at PID 36044: connection refused
W0228 23:11:33.877139   47021 main.go:329] Failure to execute command, err: 1