[PATCH] devlink: fix possible use-after-free and memory leaks in devlink_init()

From: kovalev@altlinux.org
To: netdev@vger.kernel.org
Cc: jiri@resnulli.us, davem@davemloft.net, edumazet@google.com,
	kuba@kernel.org, pabeni@redhat.com, jacob.e.keller@intel.com,
	kovalev@altlinux.org
Subject: [PATCH] devlink: fix possible use-after-free and memory leaks in devlink_init()
Date: Thu, 15 Feb 2024 23:34:00 +0300	[thread overview]
Message-ID: <20240215203400.29976-1-kovalev@altlinux.org> (raw)

From: Vasiliy Kovalev <kovalev@altlinux.org>

The pernet operations structure for the subsystem must be registered
before registering the generic netlink family.

Make an unregister in case of unsuccessful registration.

Fixes: 687125b5799c ("devlink: split out core code")
Signed-off-by: Vasiliy Kovalev <kovalev@altlinux.org>
---
 net/devlink/core.c | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/net/devlink/core.c b/net/devlink/core.c
index 4275a2bc6d8e06..b3178512878d65 100644
--- a/net/devlink/core.c
+++ b/net/devlink/core.c
@@ -529,14 +529,20 @@ static int __init devlink_init(void)
 {
 	int err;
 
-	err = genl_register_family(&devlink_nl_family);
-	if (err)
-		goto out;
 	err = register_pernet_subsys(&devlink_pernet_ops);
 	if (err)
 		goto out;
+	err = genl_register_family(&devlink_nl_family);
+	if (err)
+		goto out_unreg_pernet_subsys;
 	err = register_netdevice_notifier(&devlink_port_netdevice_nb);
+	if (!err)
+		return 0;
+
+	genl_unregister_family(&devlink_nl_family);
 
+out_unreg_pernet_subsys:
+	unregister_pernet_subsys(&devlink_pernet_ops);
 out:
 	WARN_ON(err);
 	return err;
-- 
2.33.8

