syzbot

panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x0 pc=0xf45465]

goroutine 412 gp=0xc000268fc0 m=9 mp=0xc000181c08 [running]:
panic({0x1b67d20?, 0x2b48150?})
	bazel-out/k8-fastbuild/bin/external/io_bazel_rules_go/stdlib_/src/runtime/panic.go:804 +0x168 fp=0xc0006cace8 sp=0xc0006cac38 pc=0x478628
runtime.panicmem(...)
	bazel-out/k8-fastbuild/bin/external/io_bazel_rules_go/stdlib_/src/runtime/panic.go:262
runtime.sigpanic()
	bazel-out/k8-fastbuild/bin/external/io_bazel_rules_go/stdlib_/src/runtime/signal_unix.go:900 +0x359 fp=0xc0006cad48 sp=0xc0006cace8 pc=0x47adf9
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).SendGroupSignal(0x0, 0xc000526c00)
	pkg/sentry/kernel/task_signals.go:385 +0x45 fp=0xc0006cade0 sp=0xc0006cad48 pc=0xf45465
gvisor.dev/gvisor/pkg/sentry/kernel.(*rlimitCPUSoftListener).NotifyTimer(0xc000262fb0, 0xc000262f70?)
	pkg/sentry/kernel/task_acct.go:151 +0xca fp=0xc0006cae10 sp=0xc0006cade0 pc=0xf1354a
gvisor.dev/gvisor/pkg/sentry/ktime.(*SyntheticTimer).Set(0xc000262f70, {0x0?, {0x0?}, 0x1f70580?}, 0x0)
	pkg/sentry/ktime/synthetic_timer.go:139 +0x2c5 fp=0xc0006caee8 sp=0xc0006cae10 pc=0xb18565
gvisor.dev/gvisor/pkg/sentry/kernel.(*ThreadGroup).notifyRlimitCPUUpdated(0xc000262808, 0x0)
	pkg/sentry/kernel/task_acct.go:103 +0x179 fp=0xc0006caf78 sp=0xc0006caee8 pc=0xf13079
gvisor.dev/gvisor/pkg/sentry/kernel.(*Kernel).NewThreadGroup(0xc00020d008, 0xc000285ab0, 0xc0002b5ec0, 0x0, 0xc0002b5ed0)
	pkg/sentry/kernel/thread_group.go:308 +0x75f fp=0xc0006cafe0 sp=0xc0006caf78 pc=0xf5a19f
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).Clone(0xc000c02588, 0xc0006cb598)
	pkg/sentry/kernel/task_clone.go:238 +0x2565 fp=0xc0006cb578 sp=0xc0006cafe0 pc=0xf1b645
gvisor.dev/gvisor/pkg/sentry/syscalls/linux.clone(0xc000c02588, 0x24204400, 0x40, 0x0, 0x0, 0x0)
	pkg/sentry/syscalls/linux/sys_thread.go:215 +0x125 fp=0xc0006cb668 sp=0xc0006cb578 pc=0x1216525
gvisor.dev/gvisor/pkg/sentry/syscalls/linux.Clone(0xc000c02588, 0xc000b93760?, {{0x24204400}, {0x40}, {0x0}, {0x0}, {0x0}, {0x55ca373313c8}})
	pkg/sentry/syscalls/linux/sys_clone_amd64.go:36 +0x4e fp=0xc0006cb6c8 sp=0xc0006cb668 pc=0x11a63ae
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).executeSyscall(0xc000c02588, 0x38, {{0x24204400}, {0x40}, {0x0}, {0x0}, {0x0}, {0x55ca373313c8}})
	pkg/sentry/kernel/task_syscall.go:143 +0x995 fp=0xc0006cb960 sp=0xc0006cb6c8 pc=0xf51d95
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallInvoke(0xc000c02588, 0x38, {{0x24204400}, {0x40}, {0x0}, {0x0}, {0x0}, {0x55ca373313c8}})
	pkg/sentry/kernel/task_syscall.go:323 +0x72 fp=0xc0006cba08 sp=0xc0006cb960 pc=0xf53bf2
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallEnter(0xc000c02588, 0x38, {{0x24204400}, {0x40}, {0x0}, {0x0}, {0x0}, {0x55ca373313c8}})
	pkg/sentry/kernel/task_syscall.go:283 +0x94 fp=0xc0006cba78 sp=0xc0006cba08 pc=0xf535f4
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscall(0xc000c02588)
	pkg/sentry/kernel/task_syscall.go:258 +0x4b0 fp=0xc0006cbb98 sp=0xc0006cba78 pc=0xf53190
gvisor.dev/gvisor/pkg/sentry/kernel.(*runApp).execute(0xc000c02588?, 0xc000c02588)
	pkg/sentry/kernel/task_run.go:269 +0x1fae fp=0xc0006cbe70 sp=0xc0006cbb98 pc=0xf3f2ae
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).run(0xc000c02588, 0xa)
	pkg/sentry/kernel/task_run.go:97 +0x4fb fp=0xc0006cbfb0 sp=0xc0006cbe70 pc=0xf3c91b
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).Start.gowrap1()
	pkg/sentry/kernel/task_start.go:400 +0x45 fp=0xc0006cbfe0 sp=0xc0006cbfb0 pc=0xf4fb65
runtime.goexit({})
	src/runtime/asm_amd64.s:1700 +0x1 fp=0xc0006cbfe8 sp=0xc0006cbfe0 pc=0x4819a1
created by gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).Start in goroutine 293
	pkg/sentry/kernel/task_start.go:400 +0x165