panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x0 pc=0x1959248]

goroutine 83881 [running]:
panic({0x317c20, 0x2336f70})
	GOROOT/src/runtime/panic.go:987 +0x3ac fp=0xc0017a89a0 sp=0xc0017a88e0 pc=0x121654c
runtime.panicmem()
	GOROOT/src/runtime/panic.go:260 +0x48 fp=0xc0017a89c0 sp=0xc0017a89a0 pc=0x1214ec8
runtime.sigpanic()
	GOROOT/src/runtime/signal_unix.go:837 +0x214 fp=0xc0017a8a00 sp=0xc0017a89c0 pc=0x122f094
gvisor.dev/gvisor/pkg/sentry/kernel.(*ProcessGroup).SendSignal(0x0, 0xc0017a8cd0)
	pkg/sentry/kernel/sessions.go:237 +0x48 fp=0xc0017a8b50 sp=0xc0017a8a10 pc=0x1959248
gvisor.dev/gvisor/pkg/sentry/fsimpl/devpts.(*inputQueueTransformer).transform(0x0, 0xc007a66000, 0xc007a66010, {0xc000131320, 0x109, 0x109})
	pkg/sentry/fsimpl/devpts/line_discipline.go:400 +0x41c fp=0xc0017a8da0 sp=0xc0017a8b50 pc=0x1e33f3c
gvisor.dev/gvisor/pkg/sentry/fsimpl/devpts.(*queue).pushWaitBufLocked(0xc007a66010, 0xc0074bf000?)
	pkg/sentry/fsimpl/devpts/queue.go:219 +0x18c fp=0xc0017a8e50 sp=0xc0017a8da0 pc=0x1e3790c
gvisor.dev/gvisor/pkg/sentry/fsimpl/devpts.(*queue).write(0xc007a66010, {0x7bc118, 0xc004460a80}, {{0x7b69c8, 0xc0074bf000}, {0x0, 0x1, 0x20000080, 0x109}, {0x0, ...}}, ...)
	pkg/sentry/fsimpl/devpts/queue.go:183 +0x1fc fp=0xc0017a8fa0 sp=0xc0017a8e50 pc=0x1e3701c
gvisor.dev/gvisor/pkg/sentry/fsimpl/devpts.(*lineDiscipline).inputQueueWrite(0xc007a66000, {0x7bc118, 0xc004460a80}, {{0x7b69c8, 0xc0074bf000}, {0x0, 0x1, 0x20000080, 0x109}, {0x0, ...}})
	pkg/sentry/fsimpl/devpts/line_discipline.go:217 +0xc8 fp=0xc0017a9070 sp=0xc0017a8fa0 pc=0x1e329f8
gvisor.dev/gvisor/pkg/sentry/fsimpl/devpts.(*masterFileDescription).Write(0xc00213a700, {0x7bc118, 0xc004460a80}, {{0x7b69c8, 0xc0074bf000}, {0x0, 0x1, 0x20000080, 0x109}, {0x0, ...}}, ...)
	pkg/sentry/fsimpl/devpts/master.go:134 +0xdc fp=0xc0017a9130 sp=0xc0017a9070 pc=0x1e353cc
gvisor.dev/gvisor/pkg/sentry/vfs.(*FileDescription).Write(0xc00213a700, {0x7bc118, 0xc004460a80}, {{0x7b69c8, 0xc0074bf000}, {0x0, 0x1, 0x20000080, 0x109}, {0x0, ...}}, ...)
	pkg/sentry/vfs/file_description.go:674 +0x120 fp=0xc0017a9200 sp=0xc0017a9130 pc=0x1694aa0
gvisor.dev/gvisor/pkg/sentry/syscalls/linux.write(0xc004460a80?, 0xdd24f304c2dc?, {{0x7b69c8, 0xc0074bf000}, {0x0, 0x1, 0x20000080, 0x109}, {0x0, 0x1}}, ...)
	pkg/sentry/syscalls/linux/sys_read_write.go:347 +0xc8 fp=0xc0017a9400 sp=0xc0017a9200 pc=0x1b5c1a8
gvisor.dev/gvisor/pkg/sentry/syscalls/linux.Write(0xc004460a80, {{0x4}, {0x20000080}, {0x109}, {0x0}, {0x0}, {0x0}})
	pkg/sentry/syscalls/linux/sys_read_write.go:316 +0x234 fp=0xc0017a95e0 sp=0xc0017a9400 pc=0x1b5b9f4
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).executeSyscall(0xc004460a80, 0x40, {{0x4}, {0x20000080}, {0x109}, {0x0}, {0x0}, {0x0}})
	pkg/sentry/kernel/task_syscall.go:142 +0x808 fp=0xc0017a9a00 sp=0xc0017a95e0 pc=0x1990818
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallInvoke(0xc004460a80, 0x1?, {{0x4}, {0x20000080}, {0x109}, {0x0}, {0x0}, {0x0}})
	pkg/sentry/kernel/task_syscall.go:322 +0x60 fp=0xc0017a9aa0 sp=0xc0017a9a00 pc=0x19921a0
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallEnter(0xc008080000?, 0x124e6f8?, {{0x4}, {0x20000080}, {0x109}, {0x0}, {0x0}, {0x0}})
	pkg/sentry/kernel/task_syscall.go:282 +0xa8 fp=0xc0017a9b20 sp=0xc0017a9aa0 pc=0x1991c08
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscall(0xc004460a80)
	pkg/sentry/kernel/task_syscall.go:257 +0x450 fp=0xc0017a9c50 sp=0xc0017a9b20 pc=0x1991850
gvisor.dev/gvisor/pkg/sentry/kernel.(*runApp).execute(0xc004460a80?, 0xc004460a80)
	pkg/sentry/kernel/task_run.go:265 +0x1830 fp=0xc0017a9eb0 sp=0xc0017a9c50 pc=0x197fb70
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).run(0xc004460a80, 0xec1)
	pkg/sentry/kernel/task_run.go:94 +0x214 fp=0xc0017a9fa0 sp=0xc0017a9eb0 pc=0x197db94
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).Start.func1()
	pkg/sentry/kernel/task_start.go:377 +0x44 fp=0xc0017a9fd0 sp=0xc0017a9fa0 pc=0x198e804
runtime.goexit()
	src/runtime/asm_arm64.s:1172 +0x4 fp=0xc0017a9fd0 sp=0xc0017a9fd0 pc=0x124d704
created by gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).Start
	pkg/sentry/kernel/task_start.go:377 +0x1a4