sunrpc: check that domain table is empty at module unload.

The domain table should be empty at module unload.  If it isn't there is
a bug somewhere.  So check and report.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=206651
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

diff --git a/net/sunrpc/sunrpc.h b/net/sunrpc/sunrpc.h
index 47a7565..f6fe2e6 100644 (file)
--- a/net/sunrpc/sunrpc.h
+++ b/net/sunrpc/sunrpc.h
@@ -52,4 +52,5 @@ static inline int sock_is_loopback(struct sock *sk)
 
 int rpc_clients_notifier_register(void);
 void rpc_clients_notifier_unregister(void);
+void auth_domain_cleanup(void);
 #endif /* _NET_SUNRPC_SUNRPC_H */

diff --git a/net/sunrpc/sunrpc_syms.c b/net/sunrpc/sunrpc_syms.c
index f9edaa9..236fadc 100644 (file)
--- a/net/sunrpc/sunrpc_syms.c
+++ b/net/sunrpc/sunrpc_syms.c
@@ -23,6 +23,7 @@
 #include <linux/sunrpc/rpc_pipe_fs.h>
 #include <linux/sunrpc/xprtsock.h>
 
+#include "sunrpc.h"
 #include "netns.h"
 
 unsigned int sunrpc_net_id;
@@ -131,6 +132,7 @@ cleanup_sunrpc(void)
        unregister_rpc_pipefs();
        rpc_destroy_mempool();
        unregister_pernet_subsys(&sunrpc_net_ops);
+       auth_domain_cleanup();
 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
        rpc_unregister_sysctl();
 #endif

diff --git a/net/sunrpc/svcauth.c b/net/sunrpc/svcauth.c
index 552617e..998b196 100644 (file)
--- a/net/sunrpc/svcauth.c
+++ b/net/sunrpc/svcauth.c
@@ -21,6 +21,8 @@
 
 #include <trace/events/sunrpc.h>
 
+#include "sunrpc.h"
+
 #define RPCDBG_FACILITY        RPCDBG_AUTH
 
 
@@ -205,3 +207,26 @@ struct auth_domain *auth_domain_find(char *name)
        return NULL;
 }
 EXPORT_SYMBOL_GPL(auth_domain_find);
+
+/**
+ * auth_domain_cleanup - check that the auth_domain table is empty
+ *
+ * On module unload the auth_domain_table must be empty.  To make it
+ * easier to catch bugs which don't clean up domains properly, we
+ * warn if anything remains in the table at cleanup time.
+ *
+ * Note that we cannot proactively remove the domains at this stage.
+ * The ->release() function might be in a module that has already been
+ * unloaded.
+ */
+
+void auth_domain_cleanup(void)
+{
+       int h;
+       struct auth_domain *hp;
+
+       for (h = 0; h < DN_HASHMAX; h++)
+               hlist_for_each_entry(hp, &auth_domain_table[h], hash)
+                       pr_warn("svc: domain %s still present at module unload.\n",
+                               hp->name);
+}