panic: runtime error: invalid memory address or nil pointer dereference [signal SIGSEGV: segmentation violation code=0x1 addr=0x0 pc=0x9d6041] goroutine 35762 [running]: panic({0x11ee280, 0x210cda0}) GOROOT/src/runtime/panic.go:987 +0x3bb fp=0xc0033e3360 sp=0xc0033e32a0 pc=0x436a3b runtime.panicmem(...) GOROOT/src/runtime/panic.go:260 runtime.sigpanic() GOROOT/src/runtime/signal_unix.go:837 +0x37d fp=0xc0033e33c0 sp=0xc0033e3360 pc=0x44e05d gvisor.dev/gvisor/pkg/sentry/kernel.(*TTY).SignalForegroundProcessGroup(0xc001f5bb78, 0xc003a800c3?) pkg/sentry/kernel/tty.go:54 +0xa1 fp=0xc0033e3450 sp=0xc0033e33c0 pc=0x9d6041 gvisor.dev/gvisor/pkg/sentry/fsimpl/devpts.(*inputQueueTransformer).transform(0xc003874860, 0xc002fee000, 0xc002fee010, {0xc003a80000?, 0x15f5f58?, 0xc0033e3734?}) pkg/sentry/fsimpl/devpts/line_discipline.go:411 +0x34c fp=0xc0033e3680 sp=0xc0033e3450 pc=0xd6e2ec gvisor.dev/gvisor/pkg/sentry/fsimpl/devpts.(*queue).pushWaitBufLocked(0xc002fee010, 0x15e8f90?) pkg/sentry/fsimpl/devpts/queue.go:219 +0xce fp=0xc0033e36e8 sp=0xc0033e3680 pc=0xd7130e gvisor.dev/gvisor/pkg/sentry/fsimpl/devpts.(*lineDiscipline).setTermios(0xc002fee000, 0xc003878a80?, {{0x3}, {0x5403}, {0x20000280}, {0x0}, {0x0}, {0x0}}) pkg/sentry/fsimpl/devpts/line_discipline.go:153 +0x1a5 fp=0xc0033e3788 sp=0xc0033e36e8 pc=0xd6c8c5 gvisor.dev/gvisor/pkg/sentry/fsimpl/devpts.(*replicaFileDescription).Ioctl(0xc000a49700, {0x15f5f58, 0xc003878a80}, {0x15f0490, 0xc003874000}, {{0x3}, {0x5403}, {0x20000280}, {0x0}, {0x0}, ...}) pkg/sentry/fsimpl/devpts/replica.go:168 +0x336 fp=0xc0033e3830 sp=0xc0033e3788 pc=0xd72276 gvisor.dev/gvisor/pkg/sentry/vfs.(*FileDescription).Ioctl(...) pkg/sentry/vfs/file_description.go:707 gvisor.dev/gvisor/pkg/sentry/syscalls/linux.Ioctl(0xc003878a80, {{0x3}, {0x5403}, {0x20000280}, {0x0}, {0x0}, {0x0}}) pkg/sentry/syscalls/linux/sys_file.go:286 +0x503 fp=0xc0033e3930 sp=0xc0033e3830 pc=0xb22783 gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).executeSyscall(0xc003878a80, 0x10, {{0x3}, {0x5403}, {0x20000280}, {0x0}, {0x0}, {0x0}}) pkg/sentry/kernel/task_syscall.go:142 +0x80b fp=0xc0033e3c70 sp=0xc0033e3930 pc=0x9cb66b gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallInvoke(0xc003878a80, 0x85?, {{0x3}, {0x5403}, {0x20000280}, {0x0}, {0x0}, {0x0}}) pkg/sentry/kernel/task_syscall.go:322 +0x54 fp=0xc0033e3cd0 sp=0xc0033e3c70 pc=0x9ccc54 gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallEnter(0xc0033e3d78?, 0x9829e6?, {{0x3}, {0x5403}, {0x20000280}, {0x0}, {0x0}, {0x0}}) pkg/sentry/kernel/task_syscall.go:282 +0x85 fp=0xc0033e3d30 sp=0xc0033e3cd0 pc=0x9cc845 gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscall(0xc002d90f70?) pkg/sentry/kernel/task_syscall.go:257 +0x3ac fp=0xc0033e3e28 sp=0xc0033e3d30 pc=0x9cc50c gvisor.dev/gvisor/pkg/sentry/kernel.(*runApp).execute(0xc00131d800?, 0xc003878a80) pkg/sentry/kernel/task_run.go:265 +0x144a fp=0xc0033e3f60 sp=0xc0033e3e28 pc=0x9be14a gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).run(0xc003878a80, 0x499) pkg/sentry/kernel/task_run.go:94 +0x21c fp=0xc0033e3fc0 sp=0xc0033e3f60 pc=0x9bc65c gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).Start.func1() pkg/sentry/kernel/task_start.go:377 +0x2a fp=0xc0033e3fe0 sp=0xc0033e3fc0 pc=0x9c9aea runtime.goexit() src/runtime/asm_amd64.s:1598 +0x1 fp=0xc0033e3fe8 sp=0xc0033e3fe0 pc=0x46d401 created by gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).Start pkg/sentry/kernel/task_start.go:377 +0x105