panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x0 pc=0x1aea3c0]

goroutine 274076 [running]:
panic({0x319340, 0x26ce7b0})
	GOROOT/src/runtime/panic.go:987 +0x3bb fp=0xc0007baaf0 sp=0xc0007baa30 pc=0x11b31fb
runtime.panicmem(...)
	GOROOT/src/runtime/panic.go:260
runtime.sigpanic()
	GOROOT/src/runtime/signal_unix.go:837 +0x37d fp=0xc0007bab50 sp=0xc0007baaf0 pc=0x11cc0bd
gvisor.dev/gvisor/pkg/sentry/kernel.(*TTY).SignalForegroundProcessGroup(0xc003599b90, 0x1?)
	pkg/sentry/kernel/tty.go:54 +0xe0 fp=0xc0007bac48 sp=0xc0007bab50 pc=0x1aea3c0
gvisor.dev/gvisor/pkg/sentry/fsimpl/devpts.(*inputQueueTransformer).transform(0x0, 0xc0002f8480, 0xc0002f8490, {0xc0031ee000, 0xff2e, 0xff2e})
	pkg/sentry/fsimpl/devpts/line_discipline.go:411 +0x73b fp=0xc0007bae98 sp=0xc0007bac48 pc=0x207615b
gvisor.dev/gvisor/pkg/sentry/fsimpl/devpts.(*queue).pushWaitBufLocked(0xc0002f8490, 0xc006c58000?)
	pkg/sentry/fsimpl/devpts/queue.go:219 +0x1e2 fp=0xc0007baf48 sp=0xc0007bae98 pc=0x207abe2
gvisor.dev/gvisor/pkg/sentry/fsimpl/devpts.(*queue).write(0xc0002f8490, {0x742e18, 0xc006c58000}, {{0x73d350, 0xc00425d000}, {0x0, 0x1, 0x20000280, 0xff2e}, {0x0, ...}}, ...)
	pkg/sentry/fsimpl/devpts/queue.go:183 +0x2e5 fp=0xc0007bb098 sp=0xc0007baf48 pc=0x207a0a5
gvisor.dev/gvisor/pkg/sentry/fsimpl/devpts.(*lineDiscipline).inputQueueWrite(0xc0002f8480, {0x742e18, 0xc006c58000}, {{0x73d350, 0xc00425d000}, {0x0, 0x1, 0x20000280, 0xff2e}, {0x0, ...}})
	pkg/sentry/fsimpl/devpts/line_discipline.go:220 +0xd7 fp=0xc0007bb130 sp=0xc0007bb098 pc=0x20745d7
gvisor.dev/gvisor/pkg/sentry/fsimpl/devpts.(*masterFileDescription).Write(0xc003366280, {0x742e18, 0xc006c58000}, {{0x73d350, 0xc00425d000}, {0x0, 0x1, 0x20000280, 0xff2e}, {0x0, ...}}, ...)
	pkg/sentry/fsimpl/devpts/master.go:134 +0xd6 fp=0xc0007bb1b0 sp=0xc0007bb130 pc=0x2077936
gvisor.dev/gvisor/pkg/sentry/vfs.(*FileDescription).Write(0xc003366280, {0x742e18, 0xc006c58000}, {{0x73d350, 0xc00425d000}, {0x0, 0x1, 0x20000280, 0xff2e}, {0x0, ...}}, ...)
	pkg/sentry/vfs/file_description.go:674 +0x152 fp=0xc0007bb278 sp=0xc0007bb1b0 pc=0x1729972
gvisor.dev/gvisor/pkg/sentry/syscalls/linux.write(0x0?, 0x1ce4960?, {{0x73d350, 0xc00425d000}, {0x0, 0x1, 0x20000280, 0xff2e}, {0x0, 0x1}}, ...)
	pkg/sentry/syscalls/linux/sys_read_write.go:347 +0xae fp=0xc0007bb408 sp=0xc0007bb278 pc=0x1d138ae
gvisor.dev/gvisor/pkg/sentry/syscalls/linux.Write(0xc006c58000, {{0x3}, {0x20000280}, {0xff2e}, {0x0}, {0x0}, {0x0}})
	pkg/sentry/syscalls/linux/sys_read_write.go:316 +0x34f fp=0xc0007bb5a8 sp=0xc0007bb408 pc=0x1d12e4f
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).executeSyscall(0xc006c58000, 0x1, {{0x3}, {0x20000280}, {0xff2e}, {0x0}, {0x0}, {0x0}})
	pkg/sentry/kernel/task_syscall.go:142 +0xab7 fp=0xc0007bb9c0 sp=0xc0007bb5a8 pc=0x1ad8277
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallInvoke(0xc006c58000, 0x1?, {{0x3}, {0x20000280}, {0xff2e}, {0x0}, {0x0}, {0x0}})
	pkg/sentry/kernel/task_syscall.go:322 +0x8e fp=0xc0007bba60 sp=0xc0007bb9c0 pc=0x1ada38e
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallEnter(0xc0062414a0?, 0xc0007bbb8f?, {{0x3}, {0x20000280}, {0xff2e}, {0x0}, {0x0}, {0x0}})
	pkg/sentry/kernel/task_syscall.go:282 +0xc5 fp=0xc0007bbad8 sp=0xc0007bba60 pc=0x1ad9c85
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscall(0xc006c58000)
	pkg/sentry/kernel/task_syscall.go:257 +0x53b fp=0xc0007bbc00 sp=0xc0007bbad8 pc=0x1ad979b
gvisor.dev/gvisor/pkg/sentry/kernel.(*runApp).execute(0xc006c58000?, 0xc006c58000)
	pkg/sentry/kernel/task_run.go:265 +0x22b4 fp=0xc0007bbec0 sp=0xc0007bbc00 pc=0x1ac2514
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).run(0xc006c58000, 0x1f92)
	pkg/sentry/kernel/task_run.go:94 +0x2cc fp=0xc0007bbfb0 sp=0xc0007bbec0 pc=0x1abf88c
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).Start.func1()
	pkg/sentry/kernel/task_start.go:377 +0x48 fp=0xc0007bbfe0 sp=0xc0007bbfb0 pc=0x1ad5968
runtime.goexit()
	src/runtime/asm_amd64.s:1598 +0x1 fp=0xc0007bbfe8 sp=0xc0007bbfe0 pc=0x11ec0a1
created by gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).Start
	pkg/sentry/kernel/task_start.go:377 +0x1da