panic: Decrementing non-positive ref count 0xc009d640c0, owned by kernel.ProcessGroup

goroutine 342 [running]:
panic({0x10481a0, 0xc002cfe950})
	GOROOT/src/runtime/panic.go:941 +0x397 fp=0xc0008c1408 sp=0xc0008c1348 pc=0x4358b7
gvisor.dev/gvisor/pkg/sentry/kernel.(*ProcessGroupRefs).DecRef(0xc009d640c0, 0x1?)
	bazel-out/k8-fastbuild-ST-246649c541f7/bin/pkg/sentry/kernel/process_group_refs.go:125 +0x16a fp=0xc0008c1470 sp=0xc0008c1408 pc=0x9bfc0a
gvisor.dev/gvisor/pkg/sentry/kernel.(*ProcessGroup).decRefWithParent(0xc009d640c0, 0xc0001b09c0?)
	pkg/sentry/kernel/sessions.go:159 +0x8d fp=0xc0008c14b0 sp=0xc0008c1470 pc=0x9cc58d
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).exitNotifyLocked(0xc009187500, 0x0)
	pkg/sentry/kernel/task_exit.go:714 +0x97b fp=0xc0008c1560 sp=0xc0008c14b0 pc=0x9e16fb
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).waitCollectZombieLocked(0xc000b66000, 0xc009187500, 0xc0008c18e0, 0x0?)
	pkg/sentry/kernel/task_exit.go:1109 +0x435 fp=0xc0008c15a8 sp=0xc0008c1560 pc=0x9e3435
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).waitParentLocked(0x203002?, 0xc0008c18e0, 0xc000b66000)
	pkg/sentry/kernel/task_exit.go:977 +0x131 fp=0xc0008c1668 sp=0xc0008c15a8 pc=0x9e2b11
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).waitOnce(0xc000b66000, 0xc0008c18e0)
	pkg/sentry/kernel/task_exit.go:944 +0x225 fp=0xc0008c16d0 sp=0xc0008c1668 pc=0x9e28e5
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).Wait(0x9d5c90?, 0xc0008c1800?)
	pkg/sentry/kernel/task_exit.go:917 +0x1ca fp=0xc0008c1790 sp=0xc0008c16d0 pc=0x9e244a
gvisor.dev/gvisor/pkg/sentry/syscalls/linux.wait4(0xc000b66000, 0x0?, 0x7f6a1d4d361c, 0x40000001, 0x0)
	pkg/sentry/syscalls/linux/sys_thread.go:288 +0x1b4 fp=0xc0008c1920 sp=0xc0008c1790 pc=0xaa2a14
gvisor.dev/gvisor/pkg/sentry/syscalls/linux.Wait4(0x0?, {{0xffffffff}, {0x7f6a1d4d361c}, {0x40000001}, {0x0}, {0x2baecd42}, {0x5b0}})
	pkg/sentry/syscalls/linux/sys_thread.go:316 +0x5e fp=0xc0008c1958 sp=0xc0008c1920 pc=0xaa2cde
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).executeSyscall(0xc000b66000, 0x3d, {{0xffffffff}, {0x7f6a1d4d361c}, {0x40000001}, {0x0}, {0x2baecd42}, {0x5b0}})
	pkg/sentry/kernel/task_syscall.go:142 +0x80b fp=0xc0008c1c98 sp=0xc0008c1958 pc=0x9f9b4b
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallInvoke(0xc000b66000, 0x85?, {{0xffffffff}, {0x7f6a1d4d361c}, {0x40000001}, {0x0}, {0x2baecd42}, {0x5b0}})
	pkg/sentry/kernel/task_syscall.go:322 +0x54 fp=0xc0008c1cf8 sp=0xc0008c1c98 pc=0x9fb134
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallEnter(0x88d48f?, 0x0?, {{0xffffffff}, {0x7f6a1d4d361c}, {0x40000001}, {0x0}, {0x2baecd42}, {0x5b0}})
	pkg/sentry/kernel/task_syscall.go:282 +0x85 fp=0xc0008c1d58 sp=0xc0008c1cf8 pc=0x9fad25
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscall(0xc000b4d380?)
	pkg/sentry/kernel/task_syscall.go:257 +0x3ac fp=0xc0008c1e50 sp=0xc0008c1d58 pc=0x9fa9ec
gvisor.dev/gvisor/pkg/sentry/kernel.(*runApp).execute(0x0?, 0xc000b66000)
	pkg/sentry/kernel/task_run.go:253 +0x1125 fp=0xc0008c1f60 sp=0xc0008c1e50 pc=0x9ec765
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).run(0xc000b66000, 0x25)
	pkg/sentry/kernel/task_run.go:94 +0x1ec fp=0xc0008c1fc0 sp=0xc0008c1f60 pc=0x9eafac
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).Start.func1()
	pkg/sentry/kernel/task_start.go:380 +0x2a fp=0xc0008c1fe0 sp=0xc0008c1fc0 pc=0x9f7fea
runtime.goexit()
	src/runtime/asm_amd64.s:1571 +0x1 fp=0xc0008c1fe8 sp=0xc0008c1fe0 pc=0x4695c1
created by gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).Start
	pkg/sentry/kernel/task_start.go:380 +0x105