[PATCH v1] ipv6: route: Unregister netdevice notifier on BPF init failure

[Yuho Choi]

ip6_route_init() registers ip6_route_dev_notifier before registering the
IPv6 route BPF iterator target. If bpf_iter_register() fails, the error
path jumps to out_register_late_subsys and unwinds the RTNL handlers and
late pernet subsystem, but leaves the netdevice notifier registered.

Add a separate unwind label for the BPF iterator failure path so the
netdevice notifier is unregistered before continuing with the existing
cleanup.

Fixes: 138d0be35b14 ("net: bpf: Add netlink and ipv6_route bpf_iter targets")
Signed-off-by: Yuho Choi <dbgh9129@xxxxxxxxx>
---
 net/ipv6/route.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index cb521700cee7..4333e11dc9c5 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -6925,7 +6925,7 @@ int __init ip6_route_init(void)
 #if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_PROC_FS)
 	ret = bpf_iter_register();
 	if (ret)
-		goto out_register_late_subsys;
+		goto out_register_notifier;
 #endif
 #endif
 
@@ -6939,6 +6939,12 @@ int __init ip6_route_init(void)
 out:
 	return ret;
 
+#if IS_BUILTIN(CONFIG_IPV6)
+#if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_PROC_FS)
+out_register_notifier:
+	unregister_netdevice_notifier(&ip6_route_dev_notifier);
+#endif
+#endif
 out_register_late_subsys:
 	rtnl_unregister_all(PF_INET6);
 	unregister_pernet_subsys(&ip6_route_net_late_ops);
-- 
2.43.0