panic: runtime error: invalid memory address or nil pointer dereference [signal SIGSEGV: segmentation violation code=0x1 addr=0x0 pc=0x1966568] goroutine 212595 [running]: panic({0x317be0, 0x22791d0}) GOROOT/src/runtime/panic.go:987 +0x3ac fp=0xc000eac8e0 sp=0xc000eac820 pc=0x128054c runtime.panicmem() GOROOT/src/runtime/panic.go:260 +0x48 fp=0xc000eac900 sp=0xc000eac8e0 pc=0x127eec8 runtime.sigpanic() GOROOT/src/runtime/signal_unix.go:837 +0x214 fp=0xc000eac940 sp=0xc000eac900 pc=0x1299094 gvisor.dev/gvisor/pkg/sentry/kernel.(*TTY).SignalForegroundProcessGroup(0xc0010c7098, 0x1?) pkg/sentry/kernel/tty.go:54 +0x88 fp=0xc000eaca40 sp=0xc000eac950 pc=0x1966568 gvisor.dev/gvisor/pkg/sentry/fsimpl/devpts.(*inputQueueTransformer).transform(0x21c2b00, 0xc0004b4180, 0xc0004b4190, {0xc0001b0000, 0x545, 0x545}) pkg/sentry/fsimpl/devpts/line_discipline.go:407 +0x308 fp=0xc000eacc90 sp=0xc000eaca40 pc=0x1d87dd8 gvisor.dev/gvisor/pkg/sentry/fsimpl/devpts.(*queue).pushWaitBufLocked(0xc0004b4190, 0x8500d8?) pkg/sentry/fsimpl/devpts/queue.go:219 +0x14c fp=0xc000eacd40 sp=0xc000eacc90 pc=0x1d8b21c gvisor.dev/gvisor/pkg/sentry/fsimpl/devpts.(*queue).write(0xc0004b4190, {0x8500d8, 0xc005f90000}, {{0x84a708, 0xc006b19000}, {0x0, 0x1, 0x200000c0, 0x545}, {0x0, ...}}, ...) pkg/sentry/fsimpl/devpts/queue.go:183 +0x1b0 fp=0xc000eace80 sp=0xc000eacd40 pc=0x1d8a9e0 gvisor.dev/gvisor/pkg/sentry/fsimpl/devpts.(*lineDiscipline).inputQueueWrite(0xc0004b4180, {0x8500d8, 0xc005f90000}, {{0x84a708, 0xc006b19000}, {0x0, 0x1, 0x200000c0, 0x545}, {0x0, ...}}) pkg/sentry/fsimpl/devpts/line_discipline.go:220 +0xb8 fp=0xc000eacf50 sp=0xc000eace80 pc=0x1d86d88 gvisor.dev/gvisor/pkg/sentry/fsimpl/devpts.(*masterFileDescription).Write(0xc00a021200, {0x8500d8, 0xc005f90000}, {{0x84a708, 0xc006b19000}, {0x0, 0x1, 0x200000c0, 0x545}, {0x0, ...}}, ...) pkg/sentry/fsimpl/devpts/master.go:134 +0xcc fp=0xc000ead010 sp=0xc000eacf50 pc=0x1d8906c gvisor.dev/gvisor/pkg/sentry/vfs.(*FileDescription).Write(0xc00a021200, {0x8500d8, 0xc005f90000}, {{0x84a708, 0xc006b19000}, {0x0, 0x1, 0x200000c0, 0x545}, {0x0, ...}}, ...) pkg/sentry/vfs/file_description.go:674 +0xdc fp=0xc000ead0e0 sp=0xc000ead010 pc=0x16bbabc gvisor.dev/gvisor/pkg/sentry/syscalls/linux.write(0xc005f90000?, 0xc00a021200, {{0x84a708, 0xc006b19000}, {0x0, 0x1, 0x200000c0, 0x545}, {0x0, 0x1}}, ...) pkg/sentry/syscalls/linux/sys_read_write.go:347 +0xc4 fp=0xc000ead340 sp=0xc000ead0e0 pc=0x1af6504 gvisor.dev/gvisor/pkg/sentry/syscalls/linux.Write(0xc005f90000, {{0x3}, {0x200000c0}, {0x545}, {0x0}, {0x0}, {0x0}}) pkg/sentry/syscalls/linux/sys_read_write.go:316 +0x198 fp=0xc000ead4e0 sp=0xc000ead340 pc=0x1af5e38 gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).executeSyscall(0xc005f90000, 0x40, {{0x3}, {0x200000c0}, {0x545}, {0x0}, {0x0}, {0x0}}) pkg/sentry/kernel/task_syscall.go:142 +0x6f4 fp=0xc000ead9d0 sp=0xc000ead4e0 pc=0x195a9b4 gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallInvoke(0xc005f90000, 0x125160c?, {{0x3}, {0x200000c0}, {0x545}, {0x0}, {0x0}, {0x0}}) pkg/sentry/kernel/task_syscall.go:322 +0x50 fp=0xc000eada70 sp=0xc000ead9d0 pc=0x195c020 gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallEnter(0xc000eadb38?, 0x12b8888?, {{0x3}, {0x200000c0}, {0x545}, {0x0}, {0x0}, {0x0}}) pkg/sentry/kernel/task_syscall.go:282 +0x78 fp=0xc000eadaf0 sp=0xc000eada70 pc=0x195bb48 gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscall(0xc005f90000) pkg/sentry/kernel/task_syscall.go:257 +0x3ac fp=0xc000eadc20 sp=0xc000eadaf0 pc=0x195b7ec gvisor.dev/gvisor/pkg/sentry/kernel.(*runApp).execute(0xc005f90000?, 0xc005f90000) pkg/sentry/kernel/task_run.go:265 +0x13f0 fp=0xc000eadeb0 sp=0xc000eadc20 pc=0x194b660 gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).run(0xc005f90000, 0x84c8) pkg/sentry/kernel/task_run.go:94 +0x2a0 fp=0xc000eadfa0 sp=0xc000eadeb0 pc=0x1949b00 gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).Start.func1() pkg/sentry/kernel/task_start.go:377 +0x44 fp=0xc000eadfd0 sp=0xc000eadfa0 pc=0x1958d84 runtime.goexit() src/runtime/asm_arm64.s:1172 +0x4 fp=0xc000eadfd0 sp=0xc000eadfd0 pc=0x12b7704 created by gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).Start pkg/sentry/kernel/task_start.go:377 +0x180