[SCTP]: Re-order SCTP initializations to avoid race with sctp_rcv()

Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/sctp/sctp.h b/include/net/sctp/sctp.h
index 28af68059521b52f93989bf386d38c571eaff891..dda72bf5b9b4cab8775b478b0b24c7454c8c3487 100644 (file)
--- a/include/net/sctp/sctp.h
+++ b/include/net/sctp/sctp.h
@@ -378,11 +378,15 @@ static inline int sctp_sysctl_jiffies_ms(ctl_table *table, int __user *name, int
 
 int sctp_v6_init(void);
 void sctp_v6_exit(void);
+int sctp_v6_add_protocol(void);
+void sctp_v6_del_protocol(void);
 
 #else /* #ifdef defined(CONFIG_IPV6) */
 
 static inline int sctp_v6_init(void) { return 0; }
 static inline void sctp_v6_exit(void) { return; }
+static inline int sctp_v6_add_protocol(void) { return 0; }
+static inline void sctp_v6_del_protocol(void) { return; }
 
 #endif /* #if defined(CONFIG_IPV6) */
 

diff --git a/net/sctp/ipv6.c b/net/sctp/ipv6.c
index ca527a27dd05d2a42b87c69d72ebfac36037120b..84cd53635fe8f8499b8b37ba188857ec00b05f03 100644 (file)
--- a/net/sctp/ipv6.c
+++ b/net/sctp/ipv6.c
@@ -992,45 +992,52 @@ static struct sctp_pf sctp_pf_inet6_specific = {
        .af            = &sctp_ipv6_specific,
 };
 
-/* Initialize IPv6 support and register with inet6 stack.  */
+/* Initialize IPv6 support and register with socket layer.  */
 int sctp_v6_init(void)
 {
-       int rc = proto_register(&sctpv6_prot, 1);
+       int rc;
 
+       /* Register the SCTP specific PF_INET6 functions. */
+       sctp_register_pf(&sctp_pf_inet6_specific, PF_INET6);
+
+       /* Register the SCTP specific AF_INET6 functions. */
+       sctp_register_af(&sctp_ipv6_specific);
+
+       rc = proto_register(&sctpv6_prot, 1);
        if (rc)
-               goto out;
-       /* Register inet6 protocol. */
-       rc = -EAGAIN;
-       if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0)
-               goto out_unregister_sctp_proto;
+               return rc;
 
        /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */
        inet6_register_protosw(&sctpv6_seqpacket_protosw);
        inet6_register_protosw(&sctpv6_stream_protosw);
 
-       /* Register the SCTP specific PF_INET6 functions. */
-       sctp_register_pf(&sctp_pf_inet6_specific, PF_INET6);
-
-       /* Register the SCTP specific AF_INET6 functions. */
-       sctp_register_af(&sctp_ipv6_specific);
+       return 0;
+}
 
+/* Register with inet6 layer. */
+int sctp_v6_add_protocol(void)
+{
        /* Register notifier for inet6 address additions/deletions. */
        register_inet6addr_notifier(&sctp_inet6addr_notifier);
-       rc = 0;
-out:
-       return rc;
-out_unregister_sctp_proto:
-       proto_unregister(&sctpv6_prot);
-       goto out;
+
+       if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0)
+               return -EAGAIN;
+
+       return 0;
 }
 
 /* IPv6 specific exit support. */
 void sctp_v6_exit(void)
 {
-       list_del(&sctp_ipv6_specific.list);
-       inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP);
        inet6_unregister_protosw(&sctpv6_seqpacket_protosw);
        inet6_unregister_protosw(&sctpv6_stream_protosw);
-       unregister_inet6addr_notifier(&sctp_inet6addr_notifier);
        proto_unregister(&sctpv6_prot);
+       list_del(&sctp_ipv6_specific.list);
+}
+
+/* Unregister with inet6 layer. */
+void sctp_v6_del_protocol(void)
+{
+       inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP);
+       unregister_inet6addr_notifier(&sctp_inet6addr_notifier);
 }

diff --git a/net/sctp/protocol.c b/net/sctp/protocol.c
index d4afafc39138ab5fff911d75685feda32f5f8cfa..34bab36637ac9a37345edf298cf485a45d1c9e32 100644 (file)
--- a/net/sctp/protocol.c
+++ b/net/sctp/protocol.c
@@ -975,28 +975,14 @@ SCTP_STATIC __init int sctp_init(void)
        if (!sctp_sanity_check())
                goto out;
 
-       status = proto_register(&sctp_prot, 1);
-       if (status)
-               goto out;
-
-       /* Add SCTP to inet_protos hash table.  */
-       status = -EAGAIN;
-       if (inet_add_protocol(&sctp_protocol, IPPROTO_SCTP) < 0)
-               goto err_add_protocol;
-
-       /* Add SCTP(TCP and UDP style) to inetsw linked list.  */
-       inet_register_protosw(&sctp_seqpacket_protosw);
-       inet_register_protosw(&sctp_stream_protosw);
-
-       /* Allocate a cache pools. */
+       /* Allocate bind_bucket and chunk caches. */
        status = -ENOBUFS;
        sctp_bucket_cachep = kmem_cache_create("sctp_bind_bucket",
                                               sizeof(struct sctp_bind_bucket),
                                               0, SLAB_HWCACHE_ALIGN,
                                               NULL, NULL);
-
        if (!sctp_bucket_cachep)
-               goto err_bucket_cachep;
+               goto out;
 
        sctp_chunk_cachep = kmem_cache_create("sctp_chunk",
                                               sizeof(struct sctp_chunk),
@@ -1153,6 +1139,14 @@ SCTP_STATIC __init int sctp_init(void)
        INIT_LIST_HEAD(&sctp_address_families);
        sctp_register_af(&sctp_ipv4_specific);
 
+       status = proto_register(&sctp_prot, 1);
+       if (status)
+               goto err_proto_register;
+
+       /* Register SCTP(UDP and TCP style) with socket layer.  */
+       inet_register_protosw(&sctp_seqpacket_protosw);
+       inet_register_protosw(&sctp_stream_protosw);
+
        status = sctp_v6_init();
        if (status)
                goto err_v6_init;
@@ -1166,19 +1160,39 @@ SCTP_STATIC __init int sctp_init(void)
 
        /* Initialize the local address list. */
        INIT_LIST_HEAD(&sctp_local_addr_list);
-
        sctp_get_local_addr_list();
 
        /* Register notifier for inet address additions/deletions. */
        register_inetaddr_notifier(&sctp_inetaddr_notifier);
 
+       /* Register SCTP with inet layer.  */
+       if (inet_add_protocol(&sctp_protocol, IPPROTO_SCTP) < 0) {
+               status = -EAGAIN;
+               goto err_add_protocol;
+       }
+
+       /* Register SCTP with inet6 layer.  */
+       status = sctp_v6_add_protocol();
+       if (status)
+               goto err_v6_add_protocol;
+
        __unsafe(THIS_MODULE);
        status = 0;
 out:
        return status;
+err_v6_add_protocol:
+       inet_del_protocol(&sctp_protocol, IPPROTO_SCTP);
+       unregister_inetaddr_notifier(&sctp_inetaddr_notifier);
+err_add_protocol:
+       sctp_free_local_addr_list();
+       sock_release(sctp_ctl_socket);
 err_ctl_sock_init:
        sctp_v6_exit();
 err_v6_init:
+       inet_unregister_protosw(&sctp_stream_protosw);
+       inet_unregister_protosw(&sctp_seqpacket_protosw);
+       proto_unregister(&sctp_prot);
+err_proto_register:
        sctp_sysctl_unregister();
        list_del(&sctp_ipv4_specific.list);
        free_pages((unsigned long)sctp_port_hashtable,
@@ -1192,19 +1206,13 @@ err_ehash_alloc:
                             sizeof(struct sctp_hashbucket)));
 err_ahash_alloc:
        sctp_dbg_objcnt_exit();
-err_init_proc:
        sctp_proc_exit();
+err_init_proc:
        cleanup_sctp_mibs();
 err_init_mibs:
        kmem_cache_destroy(sctp_chunk_cachep);
 err_chunk_cachep:
        kmem_cache_destroy(sctp_bucket_cachep);
-err_bucket_cachep:
-       inet_del_protocol(&sctp_protocol, IPPROTO_SCTP);
-       inet_unregister_protosw(&sctp_seqpacket_protosw);
-       inet_unregister_protosw(&sctp_stream_protosw);
-err_add_protocol:
-       proto_unregister(&sctp_prot);
        goto out;
 }
 
@@ -1215,8 +1223,9 @@ SCTP_STATIC __exit void sctp_exit(void)
         * up all the remaining associations and all that memory.
         */
 
-       /* Unregister notifier for inet address additions/deletions. */
-       unregister_inetaddr_notifier(&sctp_inetaddr_notifier);
+       /* Unregister with inet6/inet layers. */
+       sctp_v6_del_protocol();
+       inet_del_protocol(&sctp_protocol, IPPROTO_SCTP);
 
        /* Free the local address list.  */
        sctp_free_local_addr_list();
@@ -1224,7 +1233,16 @@ SCTP_STATIC __exit void sctp_exit(void)
        /* Free the control endpoint.  */
        sock_release(sctp_ctl_socket);
 
+       /* Cleanup v6 initializations. */
        sctp_v6_exit();
+
+       /* Unregister with socket layer. */
+       inet_unregister_protosw(&sctp_stream_protosw);
+       inet_unregister_protosw(&sctp_seqpacket_protosw);
+
+       /* Unregister notifier for inet address additions/deletions. */
+       unregister_inetaddr_notifier(&sctp_inetaddr_notifier);
+
        sctp_sysctl_unregister();
        list_del(&sctp_ipv4_specific.list);
 
@@ -1236,16 +1254,13 @@ SCTP_STATIC __exit void sctp_exit(void)
                   get_order(sctp_port_hashsize *
                             sizeof(struct sctp_bind_hashbucket)));
 
-       kmem_cache_destroy(sctp_chunk_cachep);
-       kmem_cache_destroy(sctp_bucket_cachep);
-
        sctp_dbg_objcnt_exit();
        sctp_proc_exit();
        cleanup_sctp_mibs();
 
-       inet_del_protocol(&sctp_protocol, IPPROTO_SCTP);
-       inet_unregister_protosw(&sctp_seqpacket_protosw);
-       inet_unregister_protosw(&sctp_stream_protosw);
+       kmem_cache_destroy(sctp_chunk_cachep);
+       kmem_cache_destroy(sctp_bucket_cachep);
+
        proto_unregister(&sctp_prot);
 }