panic: interface conversion: refs.RefCounter is *fs.File, not *fs.Dirent

goroutine 1358585 [running]:
gvisor.dev/gvisor/pkg/sentry/fs.(*Dirent).SyncAll(0xc000149c30, 0xf01a40, 0xc0078e5500)
	pkg/sentry/fs/dirent.go:335 +0x22e
DIAGNOSIS:
I0116 07:52:21.466601   14535 x:0] ***************************
I0116 07:52:21.478779   14535 x:0] Args: [/syzkaller/managers/ptrace-direct-overlay-host/current/image -root /syzkaller/managers/ptrace-direct-overlay-host/workdir/gvisor_root -watchdog-action=panic -network=none -debug -alsologtostderr -platform=ptrace -file-access=shared -network=host debug -stacks --ps ci-gvisor-ptrace-direct-overlay-host-2]
I0116 07:52:21.478823   14535 x:0] Version release-20200115.0-4-ga7a1f00425c6
I0116 07:52:21.478830   14535 x:0] PID: 14535
I0116 07:52:21.478837   14535 x:0] UID: 0, GID: 0
I0116 07:52:21.478841   14535 x:0] Configuration:
I0116 07:52:21.478848   14535 x:0] 		RootDir: /syzkaller/managers/ptrace-direct-overlay-host/workdir/gvisor_root
I0116 07:52:21.478856   14535 x:0] 		Platform: ptrace
I0116 07:52:21.478860   14535 x:0] 		FileAccess: shared, overlay: false
I0116 07:52:21.478877   14535 x:0] 		Network: host, logging: false
I0116 07:52:21.478886   14535 x:0] 		Strace: false, max size: 1024, syscalls: []
I0116 07:52:21.478891   14535 x:0] ***************************
D0116 07:52:21.480869   14535 x:0] Load container "/syzkaller/managers/ptrace-direct-overlay-host/workdir/gvisor_root" "ci-gvisor-ptrace-direct-overlay-host-2"
D0116 07:52:21.487693   14535 x:0] Signal container "ci-gvisor-ptrace-direct-overlay-host-2": signal 0
D0116 07:52:21.487722   14535 x:0] Signal sandbox "ci-gvisor-ptrace-direct-overlay-host-2"
D0116 07:52:21.487737   14535 x:0] Connecting to sandbox "ci-gvisor-ptrace-direct-overlay-host-2"
D0116 07:52:21.502770   14535 x:0] urpc: successfully marshalled 118 bytes.
I0116 07:52:21.986698   14535 x:0] Found sandbox "ci-gvisor-ptrace-direct-overlay-host-2", PID: 58440
I0116 07:52:21.986719   14535 x:0] Retrieving sandbox stacks
D0116 07:52:21.987799   14535 x:0] Stacks sandbox "ci-gvisor-ptrace-direct-overlay-host-2"
D0116 07:52:21.987825   14535 x:0] Connecting to sandbox "ci-gvisor-ptrace-direct-overlay-host-2"
D0116 07:52:21.987907   14535 x:0] urpc: successfully marshalled 36 bytes.
W0116 07:52:22.053804   14535 x:0] FATAL ERROR: retrieving stacks: getting sandbox "ci-gvisor-ptrace-direct-overlay-host-2" stacks: urpc method "debug.Stacks" failed: connection reset by peer
retrieving stacks: getting sandbox "ci-gvisor-ptrace-direct-overlay-host-2" stacks: urpc method "debug.Stacks" failed: connection reset by peer
W0116 07:52:22.053889   14535 x:0] Failure to execute command, err: 1