panic: runtime error: invalid memory address or nil pointer dereference [signal SIGSEGV: segmentation violation code=0x1 addr=0x0 pc=0x9d6041] goroutine 375361 [running]: panic({0x11ee280, 0x210cda0}) GOROOT/src/runtime/panic.go:987 +0x3bb fp=0xc007575360 sp=0xc0075752a0 pc=0x436a3b runtime.panicmem(...) GOROOT/src/runtime/panic.go:260 runtime.sigpanic() GOROOT/src/runtime/signal_unix.go:837 +0x37d fp=0xc0075753c0 sp=0xc007575360 pc=0x44e05d gvisor.dev/gvisor/pkg/sentry/kernel.(*TTY).SignalForegroundProcessGroup(0xc000dbc510, 0xc00aa2a14d?) pkg/sentry/kernel/tty.go:54 +0xa1 fp=0xc007575450 sp=0xc0075753c0 pc=0x9d6041 gvisor.dev/gvisor/pkg/sentry/fsimpl/devpts.(*inputQueueTransformer).transform(0xc0011f9400, 0xc0030f4000, 0xc0030f4010, {0xc00aa2a14d?, 0xc0075756e8?, 0xc007575734?}) pkg/sentry/fsimpl/devpts/line_discipline.go:407 +0x445 fp=0xc007575680 sp=0xc007575450 pc=0xd6e3e5 gvisor.dev/gvisor/pkg/sentry/fsimpl/devpts.(*queue).pushWaitBufLocked(0xc0030f4010, 0x15e8f90?) pkg/sentry/fsimpl/devpts/queue.go:219 +0xce fp=0xc0075756e8 sp=0xc007575680 pc=0xd7130e gvisor.dev/gvisor/pkg/sentry/fsimpl/devpts.(*lineDiscipline).setTermios(0xc0030f4000, 0x0?, {{0x3}, {0x5403}, {0x0}, {0x0}, {0x0}, {0x0}}) pkg/sentry/fsimpl/devpts/line_discipline.go:153 +0x1a5 fp=0xc007575788 sp=0xc0075756e8 pc=0xd6c8c5 gvisor.dev/gvisor/pkg/sentry/fsimpl/devpts.(*masterFileDescription).Ioctl(0xc0083a2600, {0x15f5f58, 0xc0016d3500}, {0x15f0490, 0xc0031c3000}, {{0x3}, {0x5403}, {0x0}, {0x0}, {0x0}, ...}) pkg/sentry/fsimpl/devpts/master.go:159 +0x11f fp=0xc007575830 sp=0xc007575788 pc=0xd6f3bf gvisor.dev/gvisor/pkg/sentry/vfs.(*FileDescription).Ioctl(...) pkg/sentry/vfs/file_description.go:707 gvisor.dev/gvisor/pkg/sentry/syscalls/linux.Ioctl(0xc0016d3500, {{0x3}, {0x5403}, {0x0}, {0x0}, {0x0}, {0x0}}) pkg/sentry/syscalls/linux/sys_file.go:286 +0x503 fp=0xc007575930 sp=0xc007575830 pc=0xb22783 gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).executeSyscall(0xc0016d3500, 0x10, {{0x3}, {0x5403}, {0x0}, {0x0}, {0x0}, {0x0}}) pkg/sentry/kernel/task_syscall.go:142 +0x80b fp=0xc007575c70 sp=0xc007575930 pc=0x9cb66b gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallInvoke(0xc0016d3500, 0x85?, {{0x3}, {0x5403}, {0x0}, {0x0}, {0x0}, {0x0}}) pkg/sentry/kernel/task_syscall.go:322 +0x54 fp=0xc007575cd0 sp=0xc007575c70 pc=0x9ccc54 gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallEnter(0x8415cf?, 0x0?, {{0x3}, {0x5403}, {0x0}, {0x0}, {0x0}, {0x0}}) pkg/sentry/kernel/task_syscall.go:282 +0x85 fp=0xc007575d30 sp=0xc007575cd0 pc=0x9cc845 gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscall(0xc007803110?) pkg/sentry/kernel/task_syscall.go:257 +0x3ac fp=0xc007575e28 sp=0xc007575d30 pc=0x9cc50c gvisor.dev/gvisor/pkg/sentry/kernel.(*runApp).execute(0xc0083a2b00?, 0xc0016d3500) pkg/sentry/kernel/task_run.go:265 +0x144a fp=0xc007575f60 sp=0xc007575e28 pc=0x9be14a gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).run(0xc0016d3500, 0x1a6d) pkg/sentry/kernel/task_run.go:94 +0x21c fp=0xc007575fc0 sp=0xc007575f60 pc=0x9bc65c gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).Start.func1() pkg/sentry/kernel/task_start.go:377 +0x2a fp=0xc007575fe0 sp=0xc007575fc0 pc=0x9c9aea runtime.goexit() src/runtime/asm_amd64.s:1598 +0x1 fp=0xc007575fe8 sp=0xc007575fe0 pc=0x46d401 created by gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).Start pkg/sentry/kernel/task_start.go:377 +0x105