panic: UserChainTarget should never be called.

goroutine 143662 gp=0x43fded452960 m=2 mp=0x43fdebdf8808 [running]:
panic({0xd052e0?, 0x1052bb0?})
	GOROOT/src/runtime/panic.go:879 +0x15c fp=0x43fded4c0d80 sp=0x43fded4c0cd0 pc=0x960ac
gvisor.dev/gvisor/pkg/tcpip/stack.(*UserChainTarget).Action(...)
	pkg/tcpip/stack/iptables_targets.go:174
gvisor.dev/gvisor/pkg/sentry/socket/netfilter.(*userChainTarget).Action(0x0?, 0x0?, 0x0?, 0x10?, {0x0?, 0x0?})
	<autogenerated>:1 +0x30 fp=0x43fded4c0da0 sp=0x43fded4c0d80 pc=0x6fff70
gvisor.dev/gvisor/pkg/tcpip/stack.(*IPTables).checkRule(0x45e60?, 0x3, 0x43fdee407080, {{0x43fdecabb008, 0x3, 0x4}, {0x1, 0xffffffffffffffff, 0xffffffffffffffff, 0x1, ...}, ...}, ...)
	pkg/tcpip/stack/iptables.go:774 +0x1b0 fp=0x43fded4c0fb0 sp=0x43fded4c0da0 pc=0x5d51f0
gvisor.dev/gvisor/pkg/tcpip/stack.(*IPTables).checkChain(0x43fdecced808, 0x3, 0x43fdee407080, {{0x43fdecabb008, 0x3, 0x4}, {0x1, 0xffffffffffffffff, 0xffffffffffffffff, 0x1, ...}, ...}, ...)
	pkg/tcpip/stack/iptables.go:705 +0xb0 fp=0x43fded4c10a0 sp=0x43fded4c0fb0 pc=0x5d4e70
gvisor.dev/gvisor/pkg/tcpip/stack.(*IPTables).check(0xffffffffffffff?, {{0x43fdecabb008, 0x3, 0x4}, {0x1, 0xffffffffffffffff, 0xffffffffffffffff, 0x1, 0xffffffffffffffff}, {0x2, ...}}, ...)
	pkg/tcpip/stack/iptables.go:650 +0xa0 fp=0x43fded4c1270 sp=0x43fded4c10a0 pc=0x5d4a30
gvisor.dev/gvisor/pkg/tcpip/stack.check(0x43fdecf84e18?, {{0x43fdecabb008, 0x3, 0x4}, {0x1, 0xffffffffffffffff, 0xffffffffffffffff, 0x1, 0xffffffffffffffff}, {0x2, ...}}, ...)
	pkg/tcpip/stack/iptables.go:640 +0x58 fp=0x43fded4c1340 sp=0x43fded4c1270 pc=0x5d4948
gvisor.dev/gvisor/pkg/tcpip/stack.(*IPTables).CheckOutput(0x43fdecced808, 0x43fdee407080, 0x43fdebe5c6c0, {0xfc67b0, 0x2})
	pkg/tcpip/stack/iptables.go:543 +0x204 fp=0x43fded4c19c0 sp=0x43fded4c1340 pc=0x5d43e4
gvisor.dev/gvisor/pkg/tcpip/network/ipv6.(*endpoint).WritePacket(0x43fded713508, 0x43fdebe5c6c0, {0x6, 0x40, 0x0, 0x1, 0x0}, 0x43fdee407080)
	pkg/tcpip/network/ipv6/ipv6.go:828 +0x104 fp=0x43fded4c1af0 sp=0x43fded4c19c0 pc=0x778da4
gvisor.dev/gvisor/pkg/tcpip/stack.(*Route).WritePacket(0x43fdebe5c6c0, {0x6, 0x40, 0x0, 0x1, 0x0}, 0x43fdee407080)
	pkg/tcpip/stack/route.go:510 +0x84 fp=0x43fded4c1b30 sp=0x43fded4c1af0 pc=0x5ebf94
gvisor.dev/gvisor/pkg/tcpip/transport/tcp.sendTCP(0x43fdebe5c6c0, {{0xedc5, {{0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, ...}, ...}, ...}, ...}, ...)
	pkg/tcpip/transport/tcp/connect.go:966 +0x198 fp=0x43fded4c26c0 sp=0x43fded4c1b30 pc=0x71d868
gvisor.dev/gvisor/pkg/tcpip/transport/tcp.(*Endpoint).sendTCP(0x43fded373508, 0x92866efe5c?, {{0xedc5, {{0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, ...}, ...}, ...}, ...}, ...)
	pkg/tcpip/transport/tcp/connect.go:851 +0x9c fp=0x43fded4c2780 sp=0x43fded4c26c0 pc=0x71cdbc
gvisor.dev/gvisor/pkg/tcpip/transport/tcp.(*Endpoint).sendSynTCP(0x43fded373508, 0x43fdebe5c6c0, {{0xedc5, {{0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, ...}, ...}, ...}, ...}, ...)
	pkg/tcpip/transport/tcp/connect.go:841 +0x184 fp=0x43fded4c28a0 sp=0x43fded4c2780 pc=0x71cb64
gvisor.dev/gvisor/pkg/tcpip/transport/tcp.(*handshake).start(0x43fdeca843f0)
	pkg/tcpip/transport/tcp/connect.go:594 +0x2a8 fp=0x43fded4c29f0 sp=0x43fded4c28a0 pc=0x71c078
gvisor.dev/gvisor/pkg/tcpip/transport/tcp.(*Endpoint).connect(0x43fded373508, {0x0, {{0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, ...}, ...}, ...}, ...)
	pkg/tcpip/transport/tcp/endpoint.go:2518 +0x564 fp=0x43fded4c30e0 sp=0x43fded4c29f0 pc=0x72ac94
gvisor.dev/gvisor/pkg/tcpip/transport/tcp.(*Endpoint).Connect(0x43fded373508, {0x0, {{0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, ...}, ...}, ...})
	pkg/tcpip/transport/tcp/endpoint.go:2253 +0x90 fp=0x43fded4c36e0 sp=0x43fded4c30e0 pc=0x729b20
gvisor.dev/gvisor/pkg/sentry/socket/netstack.(*sock).Connect(0x43fded3bc280, 0x43fdecb37908, {0x43fdebeec2c0?, 0x0?, 0x0?}, 0x1)
	pkg/sentry/socket/netstack/netstack.go:830 +0x2cc fp=0x43fded4c3860 sp=0x43fded4c36e0 pc=0x7a8f4c
gvisor.dev/gvisor/pkg/sentry/syscalls/linux.Connect(0x43fdecb37908, 0x1d?, {{0x9}, {0x20000080}, {0x1c}, {0x0}, {0x0}, {0x0}})
	pkg/sentry/syscalls/linux/sys_socket.go:285 +0x13c fp=0x43fded4c3940 sp=0x43fded4c3860 pc=0x8213ac
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).executeSyscall(0x43fdecb37908, 0xcb, {{0x9}, {0x20000080}, {0x1c}, {0x0}, {0x0}, {0x0}})
	pkg/sentry/kernel/task_syscall.go:143 +0x4e4 fp=0x43fded4c3c80 sp=0x43fded4c3940 pc=0x6a2834
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallInvoke(0x43fdecb37908, 0xcb, {{0x9}, {0x20000080}, {0x1c}, {0x0}, {0x0}, {0x0}})
	pkg/sentry/kernel/task_syscall.go:323 +0x3c fp=0x43fded4c3ce0 sp=0x43fded4c3c80 pc=0x6a365c
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallEnter(0x43fdecb37908, 0xcb, {{0x9}, {0x20000080}, {0x1c}, {0x0}, {0x0}, {0x0}})
	pkg/sentry/kernel/task_syscall.go:283 +0x58 fp=0x43fded4c3d30 sp=0x43fded4c3ce0 pc=0x6a3388
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscall(0x43fded37e370?)
	pkg/sentry/kernel/task_syscall.go:258 +0x238 fp=0x43fded4c3e10 sp=0x43fded4c3d30 pc=0x6a3148
gvisor.dev/gvisor/pkg/sentry/kernel.(*runApp).execute(0x43fdec3c27e0?, 0x43fdecb37908)
	pkg/sentry/kernel/task_run.go:258 +0xd04 fp=0x43fded4c3f10 sp=0x43fded4c3e10 pc=0x699624
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).run(0x43fdecb37908, 0x9d14)
	pkg/sentry/kernel/task_run.go:89 +0x1a8 fp=0x43fded4c3fb0 sp=0x43fded4c3f10 pc=0x698478
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).Start.gowrap1()
	pkg/sentry/kernel/task_start.go:531 +0x20 fp=0x43fded4c3fd0 sp=0x43fded4c3fb0 pc=0x6a15b0
runtime.goexit({})
	src/runtime/asm_arm64.s:1447 +0x4 fp=0x43fded4c3fd0 sp=0x43fded4c3fd0 pc=0x9e984
created by gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).Start in goroutine 142212
	pkg/sentry/kernel/task_start.go:531 +0xc0