SUNRPC: Ensure that the struct gss_auth lifetime exceeds the credential's
Add a refcount in order to ensure that the gss_auth doesn't disappear from
underneath us while we're freeing up GSS contexts.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/net/sunrpc/auth_gss/auth_gss.c b/net/sunrpc/auth_gss/auth_gss.c
index debcda8..982aba6 100644
--- a/net/sunrpc/auth_gss/auth_gss.c
+++ b/net/sunrpc/auth_gss/auth_gss.c
@@ -79,6 +79,7 @@
#define isprint(c) ((c > 0x1f) && (c < 0x7f))
struct gss_auth {
+ struct kref kref;
struct rpc_auth rpc_auth;
struct gss_api_mech *mech;
enum rpc_gss_svc service;
@@ -636,6 +637,7 @@
auth->au_ops = &authgss_ops;
auth->au_flavor = flavor;
atomic_set(&auth->au_count, 1);
+ kref_init(&gss_auth->kref);
gss_auth->dentry = rpc_mkpipe(clnt->cl_dentry, gss_auth->mech->gm_name,
clnt, &gss_upcall_ops, RPC_PIPE_WAIT_FOR_OPEN);
@@ -661,6 +663,25 @@
}
static void
+gss_free(struct gss_auth *gss_auth)
+{
+ rpc_unlink(gss_auth->dentry);
+ gss_auth->dentry = NULL;
+ gss_mech_put(gss_auth->mech);
+
+ kfree(gss_auth);
+ module_put(THIS_MODULE);
+}
+
+static void
+gss_free_callback(struct kref *kref)
+{
+ struct gss_auth *gss_auth = container_of(kref, struct gss_auth, kref);
+
+ gss_free(gss_auth);
+}
+
+static void
gss_destroy(struct rpc_auth *auth)
{
struct gss_auth *gss_auth;
@@ -671,12 +692,7 @@
rpcauth_destroy_credcache(auth);
gss_auth = container_of(auth, struct gss_auth, rpc_auth);
- rpc_unlink(gss_auth->dentry);
- gss_auth->dentry = NULL;
- gss_mech_put(gss_auth->mech);
-
- kfree(gss_auth);
- module_put(THIS_MODULE);
+ kref_put(&gss_auth->kref, gss_free_callback);
}
/* gss_destroy_cred (and gss_destroy_ctx) are used to clean up after failure
@@ -725,12 +741,14 @@
gss_destroy_cred(struct rpc_cred *cred)
{
struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base);
+ struct gss_auth *gss_auth = container_of(cred->cr_auth, struct gss_auth, rpc_auth);
struct gss_cl_ctx *ctx = gss_cred->gc_ctx;
rcu_assign_pointer(gss_cred->gc_ctx, NULL);
call_rcu(&cred->cr_rcu, gss_free_cred_callback);
if (ctx)
gss_put_ctx(ctx);
+ kref_put(&gss_auth->kref, gss_free_callback);
}
/*
@@ -762,6 +780,7 @@
*/
cred->gc_base.cr_flags = 1UL << RPCAUTH_CRED_NEW;
cred->gc_service = gss_auth->service;
+ kref_get(&gss_auth->kref);
return &cred->gc_base;
out_err:
