NFSv4: Reintroduce machine creds
We need to try to ensure that we always use the same credentials whenever
we re-establish the clientid on the server. If not, the server won't
recognise that we're the same client, and so may not allow us to recover
state.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index 93dfd75..f2f3b28 100644
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -112,6 +112,7 @@
static struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *cl_init)
{
struct nfs_client *clp;
+ struct rpc_cred *cred;
if ((clp = kzalloc(sizeof(*clp), GFP_KERNEL)) == NULL)
goto error_0;
@@ -150,6 +151,9 @@
clp->cl_boot_time = CURRENT_TIME;
clp->cl_state = 1 << NFS4CLNT_LEASE_EXPIRED;
#endif
+ cred = rpc_lookup_machine_cred();
+ if (!IS_ERR(cred))
+ clp->cl_machine_cred = cred;
return clp;
@@ -191,6 +195,9 @@
if (__test_and_clear_bit(NFS_CS_CALLBACK, &clp->cl_res_state))
nfs_callback_down();
+ if (clp->cl_machine_cred != NULL)
+ put_rpccred(clp->cl_machine_cred);
+
kfree(clp->cl_hostname);
kfree(clp);
diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h
index ac7e4fb..c9beacd 100644
--- a/include/linux/nfs_fs_sb.h
+++ b/include/linux/nfs_fs_sb.h
@@ -32,6 +32,8 @@
const struct nfs_rpc_ops *rpc_ops; /* NFS protocol vector */
int cl_proto; /* Network transport protocol */
+ struct rpc_cred *cl_machine_cred;
+
#ifdef CONFIG_NFS_V4
u64 cl_clientid; /* constant */
nfs4_verifier cl_confirm;
diff --git a/include/linux/sunrpc/auth.h b/include/linux/sunrpc/auth.h
index a19c3af..3f63218 100644
--- a/include/linux/sunrpc/auth.h
+++ b/include/linux/sunrpc/auth.h
@@ -26,6 +26,7 @@
uid_t uid;
gid_t gid;
struct group_info *group_info;
+ unsigned char machine_cred : 1;
};
/*
@@ -130,6 +131,7 @@
void __exit rpc_destroy_generic_auth(void);
struct rpc_cred * rpc_lookup_cred(void);
+struct rpc_cred * rpc_lookup_machine_cred(void);
int rpcauth_register(const struct rpc_authops *);
int rpcauth_unregister(const struct rpc_authops *);
struct rpc_auth * rpcauth_create(rpc_authflavor_t, struct rpc_clnt *);
diff --git a/include/linux/sunrpc/auth_gss.h b/include/linux/sunrpc/auth_gss.h
index 67658e1..fec6899 100644
--- a/include/linux/sunrpc/auth_gss.h
+++ b/include/linux/sunrpc/auth_gss.h
@@ -84,6 +84,7 @@
enum rpc_gss_svc gc_service;
struct gss_cl_ctx *gc_ctx;
struct gss_upcall_msg *gc_upcall;
+ unsigned char gc_machine_cred : 1;
};
#endif /* __KERNEL__ */
diff --git a/net/sunrpc/auth_generic.c b/net/sunrpc/auth_generic.c
index b6f124c..d927d9f 100644
--- a/net/sunrpc/auth_generic.c
+++ b/net/sunrpc/auth_generic.c
@@ -17,6 +17,9 @@
# define RPCDBG_FACILITY RPCDBG_AUTH
#endif
+#define RPC_ANONYMOUS_USERID ((uid_t)-2)
+#define RPC_ANONYMOUS_GROUPID ((gid_t)-2)
+
struct generic_cred {
struct rpc_cred gc_base;
struct auth_cred acred;
@@ -35,6 +38,22 @@
}
EXPORT_SYMBOL_GPL(rpc_lookup_cred);
+/*
+ * Public call interface for looking up machine creds.
+ */
+struct rpc_cred *rpc_lookup_machine_cred(void)
+{
+ struct auth_cred acred = {
+ .uid = RPC_ANONYMOUS_USERID,
+ .gid = RPC_ANONYMOUS_GROUPID,
+ .machine_cred = 1,
+ };
+
+ dprintk("RPC: looking up machine cred\n");
+ return generic_auth.au_ops->lookup_cred(&generic_auth, &acred, 0);
+}
+EXPORT_SYMBOL_GPL(rpc_lookup_machine_cred);
+
static void
generic_bind_cred(struct rpc_task *task, struct rpc_cred *cred)
{
@@ -75,8 +94,10 @@
gcred->acred.group_info = acred->group_info;
if (gcred->acred.group_info != NULL)
get_group_info(gcred->acred.group_info);
+ gcred->acred.machine_cred = acred->machine_cred;
- dprintk("RPC: allocated generic cred %p for uid %d gid %d\n",
+ dprintk("RPC: allocated %s cred %p for uid %d gid %d\n",
+ gcred->acred.machine_cred ? "machine" : "generic",
gcred, acred->uid, acred->gid);
return &gcred->gc_base;
}
@@ -115,7 +136,8 @@
if (gcred->acred.uid != acred->uid ||
gcred->acred.gid != acred->gid ||
- gcred->acred.group_info != acred->group_info)
+ gcred->acred.group_info != acred->group_info ||
+ gcred->acred.machine_cred != acred->machine_cred)
return 0;
return 1;
}
diff --git a/net/sunrpc/auth_gss/auth_gss.c b/net/sunrpc/auth_gss/auth_gss.c
index 7567eb9..46f7ec8 100644
--- a/net/sunrpc/auth_gss/auth_gss.c
+++ b/net/sunrpc/auth_gss/auth_gss.c
@@ -371,9 +371,16 @@
static struct gss_upcall_msg *
gss_setup_upcall(struct rpc_clnt *clnt, struct gss_auth *gss_auth, struct rpc_cred *cred)
{
+ struct gss_cred *gss_cred = container_of(cred,
+ struct gss_cred, gc_base);
struct gss_upcall_msg *gss_new, *gss_msg;
+ uid_t uid = cred->cr_uid;
- gss_new = gss_alloc_msg(gss_auth, cred->cr_uid);
+ /* Special case: rpc.gssd assumes that uid == 0 implies machine creds */
+ if (gss_cred->gc_machine_cred != 0)
+ uid = 0;
+
+ gss_new = gss_alloc_msg(gss_auth, uid);
if (gss_new == NULL)
return ERR_PTR(-ENOMEM);
gss_msg = gss_add_msg(gss_auth, gss_new);
@@ -818,6 +825,7 @@
*/
cred->gc_base.cr_flags = 1UL << RPCAUTH_CRED_NEW;
cred->gc_service = gss_auth->service;
+ cred->gc_machine_cred = acred->machine_cred;
kref_get(&gss_auth->kref);
return &cred->gc_base;
@@ -855,6 +863,8 @@
if (gss_cred->gc_ctx && time_after(jiffies, gss_cred->gc_ctx->gc_expiry))
return 0;
out:
+ if (acred->machine_cred != gss_cred->gc_machine_cred)
+ return 0;
return (rc->cr_uid == acred->uid);
}