panic: runtime error: invalid memory address or nil pointer dereference [signal SIGSEGV: segmentation violation code=0x1 addr=0x0 pc=0x94b45d] goroutine 295265 [running]: panic({0x10ec220, 0x1e67c20}) GOROOT/src/runtime/panic.go:987 +0x3bb fp=0xc0014a8ff0 sp=0xc0014a8f30 pc=0x436c1b runtime.panicmem(...) GOROOT/src/runtime/panic.go:260 runtime.sigpanic() GOROOT/src/runtime/signal_unix.go:837 +0x37d fp=0xc0014a9050 sp=0xc0014a8ff0 pc=0x44e23d gvisor.dev/gvisor/pkg/sentry/kernel.(*TTY).SignalForegroundProcessGroup(0x1ec6308?, 0xc0002f0905?) pkg/sentry/kernel/tty.go:54 +0x9d fp=0xc0014a90e0 sp=0xc0014a9050 pc=0x94b45d gvisor.dev/gvisor/pkg/sentry/fsimpl/devpts.(*inputQueueTransformer).transform(0x468, 0xc0032ec180, 0xc0032ec190, {0xc0002f0900?, 0xc0058ac1c0?, 0x0?}) pkg/sentry/fsimpl/devpts/line_discipline.go:407 +0x34e fp=0xc0014a9308 sp=0xc0014a90e0 pc=0xc896ae gvisor.dev/gvisor/pkg/sentry/fsimpl/devpts.(*queue).pushWaitBufLocked(0xc0032ec190, 0xc006792000?) pkg/sentry/fsimpl/devpts/queue.go:219 +0x99 fp=0xc0014a9370 sp=0xc0014a9308 pc=0xc8bf99 gvisor.dev/gvisor/pkg/sentry/fsimpl/devpts.(*queue).write(0xc0032ec190, {0x14c8e18, 0xc006599500}, {{0x14c30d0, 0xc006792000}, {0x0, 0x1, 0x20000ac0, 0x468}, {0x0, ...}}, ...) pkg/sentry/fsimpl/devpts/queue.go:183 +0x214 fp=0xc0014a9450 sp=0xc0014a9370 pc=0xc8b954 gvisor.dev/gvisor/pkg/sentry/fsimpl/devpts.(*lineDiscipline).inputQueueWrite(0xc0032ec180, {0x14c8e18?, 0xc006599500?}, {{0x14c30d0, 0xc006792000}, {0x0, 0x1, 0x20000ac0, 0x468}, {0x0, ...}}) pkg/sentry/fsimpl/devpts/line_discipline.go:220 +0xbf fp=0xc0014a94d8 sp=0xc0014a9450 pc=0xc8881f gvisor.dev/gvisor/pkg/sentry/fsimpl/devpts.(*masterFileDescription).Write(0x0?, {0x14c8e18?, 0xc006599500?}, {{0x14c30d0, 0xc006792000}, {0x0, 0x1, 0x20000ac0, 0x468}, {0x0, ...}}, ...) pkg/sentry/fsimpl/devpts/master.go:134 +0x5b fp=0xc0014a9538 sp=0xc0014a94d8 pc=0xc8a2db gvisor.dev/gvisor/pkg/sentry/vfs.(*FileDescription).Write(0xc00659a980, {0x14c8e18, 0xc006599500}, {{0x14c30d0, 0xc006792000}, {0x0, 0x1, 0x20000ac0, 0x468}, {0x0, ...}}, ...) pkg/sentry/vfs/file_description.go:674 +0x91 fp=0xc0014a95b8 sp=0xc0014a9538 pc=0x73fa31 gvisor.dev/gvisor/pkg/sentry/syscalls/linux.write(0xffffffff?, 0xc00659a980, {{0x14c30d0, 0xc006792000}, {0x0, 0x1, 0x20000ac0, 0x468}, {0x0, 0x1}}, ...) pkg/sentry/syscalls/linux/sys_read_write.go:347 +0x85 fp=0xc0014a9778 sp=0xc0014a95b8 pc=0xa85ee5 gvisor.dev/gvisor/pkg/sentry/syscalls/linux.Write(0xc006599500, {{0x8}, {0x20000ac0}, {0x468}, {0x0}, {0x0}, {0x0}}) pkg/sentry/syscalls/linux/sys_read_write.go:316 +0x1c5 fp=0xc0014a9880 sp=0xc0014a9778 pc=0xa857c5 gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).executeSyscall(0xc006599500, 0x1, {{0x8}, {0x20000ac0}, {0x468}, {0x0}, {0x0}, {0x0}}) pkg/sentry/kernel/task_syscall.go:142 +0x755 fp=0xc0014a9c70 sp=0xc0014a9880 pc=0x942635 gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallInvoke(0xc006599500, 0x85?, {{0x8}, {0x20000ac0}, {0x468}, {0x0}, {0x0}, {0x0}}) pkg/sentry/kernel/task_syscall.go:322 +0x4a fp=0xc0014a9cd0 sp=0xc0014a9c70 pc=0x94386a gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallEnter(0x8fa11a?, 0xc003812e20?, {{0x8}, {0x20000ac0}, {0x468}, {0x0}, {0x0}, {0x0}}) pkg/sentry/kernel/task_syscall.go:282 +0x65 fp=0xc0014a9d30 sp=0xc0014a9cd0 pc=0x943545 gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscall(0xc009ad81a0?) pkg/sentry/kernel/task_syscall.go:257 +0x2f0 fp=0xc0014a9e28 sp=0xc0014a9d30 pc=0x9432b0 gvisor.dev/gvisor/pkg/sentry/kernel.(*runApp).execute(0xc0054e8700?, 0xc006599500) pkg/sentry/kernel/task_run.go:265 +0x103e fp=0xc0014a9f60 sp=0xc0014a9e28 pc=0x9374de gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).run(0xc006599500, 0x21a0) pkg/sentry/kernel/task_run.go:94 +0x1b8 fp=0xc0014a9fc0 sp=0xc0014a9f60 pc=0x935e78 gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).Start.func1() pkg/sentry/kernel/task_start.go:377 +0x2a fp=0xc0014a9fe0 sp=0xc0014a9fc0 pc=0x940e2a runtime.goexit() src/runtime/asm_amd64.s:1598 +0x1 fp=0xc0014a9fe8 sp=0xc0014a9fe0 pc=0x46d5e1 created by gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).Start pkg/sentry/kernel/task_start.go:377 +0xef