panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x0 pc=0x1ae2d4d]

goroutine 1939891 [running]:
panic({0x3192e0, 0x2647070})
	GOROOT/src/runtime/panic.go:987 +0x3bb fp=0xc000f5ea08 sp=0xc000f5e948 pc=0x125ea7b
runtime.panicmem(...)
	GOROOT/src/runtime/panic.go:260
runtime.sigpanic()
	GOROOT/src/runtime/signal_unix.go:837 +0x37d fp=0xc000f5ea68 sp=0xc000f5ea08 pc=0x127793d
gvisor.dev/gvisor/pkg/sentry/kernel.(*TTY).SignalForegroundProcessGroup(0xc00ba4d188, 0x1?)
	pkg/sentry/kernel/tty.go:54 +0xcd fp=0xc000f5eb58 sp=0xc000f5ea68 pc=0x1ae2d4d
gvisor.dev/gvisor/pkg/sentry/fsimpl/devpts.(*inputQueueTransformer).transform(0x123540a, 0xc0002da000, 0xc0002da010, {0xc0082ea6c0, 0xb3, 0xb3})
	pkg/sentry/fsimpl/devpts/line_discipline.go:411 +0x596 fp=0xc000f5edb0 sp=0xc000f5eb58 pc=0x1ffcf96
gvisor.dev/gvisor/pkg/sentry/fsimpl/devpts.(*queue).pushWaitBufLocked(0xc0002da010, 0xc0051b7000?)
	pkg/sentry/fsimpl/devpts/queue.go:219 +0x19f fp=0xc000f5ee60 sp=0xc000f5edb0 pc=0x200117f
gvisor.dev/gvisor/pkg/sentry/fsimpl/devpts.(*queue).write(0xc0002da010, {0x819e18, 0xc008848000}, {{0x8140d0, 0xc0051b7000}, {0x0, 0x1, 0x20000100, 0xb3}, {0x0, ...}}, ...)
	pkg/sentry/fsimpl/devpts/queue.go:183 +0x269 fp=0xc000f5ef98 sp=0xc000f5ee60 pc=0x2000729
gvisor.dev/gvisor/pkg/sentry/fsimpl/devpts.(*lineDiscipline).inputQueueWrite(0xc0002da000, {0x819e18, 0xc008848000}, {{0x8140d0, 0xc0051b7000}, {0x0, 0x1, 0x20000100, 0xb3}, {0x0, ...}})
	pkg/sentry/fsimpl/devpts/line_discipline.go:220 +0xc6 fp=0xc000f5f030 sp=0xc000f5ef98 pc=0x1ffba46
gvisor.dev/gvisor/pkg/sentry/fsimpl/devpts.(*masterFileDescription).Write(0xc0071cdb80, {0x819e18, 0xc008848000}, {{0x8140d0, 0xc0051b7000}, {0x0, 0x1, 0x20000100, 0xb3}, {0x0, ...}}, ...)
	pkg/sentry/fsimpl/devpts/master.go:134 +0xc5 fp=0xc000f5f0b0 sp=0xc000f5f030 pc=0x1ffe525
gvisor.dev/gvisor/pkg/sentry/vfs.(*FileDescription).Write(0xc0071cdb80, {0x819e18, 0xc008848000}, {{0x8140d0, 0xc0051b7000}, {0x0, 0x1, 0x20000100, 0xb3}, {0x0, ...}}, ...)
	pkg/sentry/vfs/file_description.go:674 +0x125 fp=0xc000f5f180 sp=0xc000f5f0b0 pc=0x178d5c5
gvisor.dev/gvisor/pkg/sentry/syscalls/linux.write(0xc0ffffffff?, 0xc0071cdb80, {{0x8140d0, 0xc0051b7000}, {0x0, 0x1, 0x20000100, 0xb3}, {0x0, 0x1}}, ...)
	pkg/sentry/syscalls/linux/sys_read_write.go:347 +0x9d fp=0xc000f5f370 sp=0xc000f5f180 pc=0x1cdc7dd
gvisor.dev/gvisor/pkg/sentry/syscalls/linux.Write(0xc008848000, {{0x3}, {0x20000100}, {0xb3}, {0x0}, {0x0}, {0x0}})
	pkg/sentry/syscalls/linux/sys_read_write.go:316 +0x275 fp=0xc000f5f4d8 sp=0xc000f5f370 pc=0x1cdbe95
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).executeSyscall(0xc008848000, 0x1, {{0x3}, {0x20000100}, {0xb3}, {0x0}, {0x0}, {0x0}})
	pkg/sentry/kernel/task_syscall.go:142 +0x9b9 fp=0xc000f5f9b8 sp=0xc000f5f4d8 pc=0x1ad3cd9
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallInvoke(0xc008848000, 0x0?, {{0x3}, {0x20000100}, {0xb3}, {0x0}, {0x0}, {0x0}})
	pkg/sentry/kernel/task_syscall.go:322 +0x7d fp=0xc000f5fa50 sp=0xc000f5f9b8 pc=0x1ad5abd
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallEnter(0xc00511aea0?, 0xc00a3201e0?, {{0x3}, {0x20000100}, {0xb3}, {0x0}, {0x0}, {0x0}})
	pkg/sentry/kernel/task_syscall.go:282 +0x8f fp=0xc000f5fac8 sp=0xc000f5fa50 pc=0x1ad546f
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscall(0xc008848000)
	pkg/sentry/kernel/task_syscall.go:257 +0x4c5 fp=0xc000f5fbf0 sp=0xc000f5fac8 pc=0x1ad5005
gvisor.dev/gvisor/pkg/sentry/kernel.(*runApp).execute(0xc008848000?, 0xc008848000)
	pkg/sentry/kernel/task_run.go:265 +0x1d4b fp=0xc000f5fec8 sp=0xc000f5fbf0 pc=0x1abfa4b
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).run(0xc008848000, 0xfafb)
	pkg/sentry/kernel/task_run.go:94 +0x36b fp=0xc000f5ffb0 sp=0xc000f5fec8 pc=0x1abd36b
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).Start.func1()
	pkg/sentry/kernel/task_start.go:377 +0x48 fp=0xc000f5ffe0 sp=0xc000f5ffb0 pc=0x1ad17e8
runtime.goexit()
	src/runtime/asm_amd64.s:1598 +0x1 fp=0xc000f5ffe8 sp=0xc000f5ffe0 pc=0x1297921
created by gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).Start
	pkg/sentry/kernel/task_start.go:377 +0x1ad