Patch "ipv6: sr: fix possible use-after-free and null-ptr-deref" has been added to the 4.19-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    ipv6: sr: fix possible use-after-free and null-ptr-deref

to the 4.19-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     ipv6-sr-fix-possible-use-after-free-and-null-ptr-der.patch
and it can be found in the queue-4.19 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit dde5d62ac7e339e19b48741665fb64593eca9890
Author: Vasiliy Kovalev <kovalev@xxxxxxxxxxxx>
Date:   Thu Feb 15 23:27:17 2024 +0300

    ipv6: sr: fix possible use-after-free and null-ptr-deref
    
    [ Upstream commit 5559cea2d5aa3018a5f00dd2aca3427ba09b386b ]
    
    The pernet operations structure for the subsystem must be registered
    before registering the generic netlink family.
    
    Fixes: 915d7e5e5930 ("ipv6: sr: add code base for control plane support of SR-IPv6")
    Signed-off-by: Vasiliy Kovalev <kovalev@xxxxxxxxxxxx>
    Link: https://lore.kernel.org/r/20240215202717.29815-1-kovalev@xxxxxxxxxxxx
    Signed-off-by: Paolo Abeni <pabeni@xxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/net/ipv6/seg6.c b/net/ipv6/seg6.c
index 89d55770ac74b..4bd601c964343 100644
--- a/net/ipv6/seg6.c
+++ b/net/ipv6/seg6.c
@@ -445,22 +445,24 @@ int __init seg6_init(void)
 {
 	int err = -ENOMEM;
 
-	err = genl_register_family(&seg6_genl_family);
+	err = register_pernet_subsys(&ip6_segments_ops);
 	if (err)
 		goto out;
 
-	err = register_pernet_subsys(&ip6_segments_ops);
+	err = genl_register_family(&seg6_genl_family);
 	if (err)
-		goto out_unregister_genl;
+		goto out_unregister_pernet;
 
 #ifdef CONFIG_IPV6_SEG6_LWTUNNEL
 	err = seg6_iptunnel_init();
 	if (err)
-		goto out_unregister_pernet;
+		goto out_unregister_genl;
 
 	err = seg6_local_init();
-	if (err)
-		goto out_unregister_pernet;
+	if (err) {
+		seg6_iptunnel_exit();
+		goto out_unregister_genl;
+	}
 #endif
 
 #ifdef CONFIG_IPV6_SEG6_HMAC
@@ -481,11 +483,11 @@ int __init seg6_init(void)
 #endif
 #endif
 #ifdef CONFIG_IPV6_SEG6_LWTUNNEL
-out_unregister_pernet:
-	unregister_pernet_subsys(&ip6_segments_ops);
-#endif
 out_unregister_genl:
 	genl_unregister_family(&seg6_genl_family);
+#endif
+out_unregister_pernet:
+	unregister_pernet_subsys(&ip6_segments_ops);
 	goto out;
 }