panic: runtime error: index out of range

goroutine 612525 [running]:
unicode/utf8.EncodeRune(0xc0010f4149, 0x1, 0x7, 0xfe, 0xfe)
	GOROOT/src/unicode/utf8/utf8.go:346 +0x148
gvisor.googlesource.com/gvisor/pkg/sentry/fs/tty.(*outputQueueTransformer).transform(0x146a610, 0xc000e782c0, 0xc000e78328, 0xc000c522ca, 0x13c, 0x13c, 0x8)
	pkg/sentry/fs/tty/line_discipline.go:325 +0x2ee
gvisor.googlesource.com/gvisor/pkg/sentry/fs/tty.(*queue).pushWaitBufLocked(0xc000e78328, 0xc000e782c0, 0xc000c92a80)
	pkg/sentry/fs/tty/queue.go:227 +0xa2
gvisor.googlesource.com/gvisor/pkg/sentry/fs/tty.(*queue).write(0xc000e78328, 0xdf9be0, 0xc000c92a80, 0xdf8c20, 0xc0009ed600, 0x0, 0x1, 0x20000100, 0x146, 0x100, ...)
	pkg/sentry/fs/tty/queue.go:187 +0x1b2
gvisor.googlesource.com/gvisor/pkg/sentry/fs/tty.(*lineDiscipline).outputQueueWrite(0xc000e782c0, 0xdf9be0, 0xc000c92a80, 0xdf8c20, 0xc0009ed600, 0x0, 0x1, 0x20000100, 0x146, 0x100, ...)
	pkg/sentry/fs/tty/line_discipline.go:240 +0xef
gvisor.googlesource.com/gvisor/pkg/sentry/fs/tty.(*slaveFileOperations).Write(0xc000372248, 0xdf9be0, 0xc000c92a80, 0xc000ac2ab0, 0xdf8c20, 0xc0009ed600, 0x0, 0x1, 0x20000100, 0x146, ...)
	pkg/sentry/fs/tty/slave.go:125 +0x88
gvisor.googlesource.com/gvisor/pkg/sentry/fs.(*File).Writev(0xc000ac2ab0, 0xdf9be0, 0xc000c92a80, 0xdf8c20, 0xc0009ed600, 0x0, 0x1, 0x20000100, 0x146, 0x100, ...)
	pkg/sentry/fs/file.go:314 +0x172
gvisor.googlesource.com/gvisor/pkg/sentry/syscalls/linux.writev(0xc000c92a80, 0xc000ac2ab0, 0xdf8c20, 0xc0009ed600, 0x0, 0x1, 0x20000100, 0x146, 0x100, 0x146, ...)
	pkg/sentry/syscalls/linux/sys_write.go:261 +0x90
gvisor.googlesource.com/gvisor/pkg/sentry/syscalls/linux.Write(0xc000c92a80, 0x4, 0x20000100, 0x146, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, ...)
	pkg/sentry/syscalls/linux/sys_write.go:71 +0x1d1
gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).executeSyscall(0xc000c92a80, 0x1, 0x4, 0x20000100, 0x146, 0x0, 0x0, 0x0, 0xc000fd4d08, 0xc000fd4dc0, ...)
	pkg/sentry/kernel/task_syscall.go:165 +0x10a
gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).doSyscallInvoke(0xc000c92a80, 0x1, 0x4, 0x20000100, 0x146, 0x0, 0x0, 0x0, 0x0, 0x0)
	pkg/sentry/kernel/task_syscall.go:283 +0x69
gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).doSyscallEnter(0xc000c92a80, 0x1, 0x4, 0x20000100, 0x146, 0x0, 0x0, 0x0, 0xc0005b8e40, 0xe09640)
	pkg/sentry/kernel/task_syscall.go:244 +0x96
gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).doSyscall(0xc000c92a80, 0x2, 0xc000518500)
	pkg/sentry/kernel/task_syscall.go:219 +0x13d
gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*runApp).execute(0x0, 0xc000c92a80, 0xde1480, 0x0)
	pkg/sentry/kernel/task_run.go:215 +0x109b
gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).run(0xc000c92a80, 0x329e)
	pkg/sentry/kernel/task_run.go:91 +0x194
created by gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).Start
	pkg/sentry/kernel/task_start.go:279 +0xfe