RPC: make rpcauth_lookupcred() return error codes.

 So we can distinguish between ENOMEM and EACCES errors.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

fs/nfs/dir.c

@@ -1532,8 +1532,11 @@ int nfs_permission(struct inode *inode, int mask, struct nameidata *nd)
 		goto out_notsup;
 
 	cred = rpcauth_lookupcred(NFS_CLIENT(inode)->cl_auth, 0);
-	res = nfs_do_access(inode, cred, mask);
-	put_rpccred(cred);
+	if (!IS_ERR(cred)) {
+		res = nfs_do_access(inode, cred, mask);
+		put_rpccred(cred);
+	} else
+		res = PTR_ERR(cred);
 	unlock_kernel();
 out:
 	return res;

fs/nfs/inode.c

@@ -918,8 +918,9 @@ int nfs_open(struct inode *inode, struct file *filp)
 	struct nfs_open_context *ctx;
 	struct rpc_cred *cred;
 
-	if ((cred = rpcauth_lookupcred(NFS_CLIENT(inode)->cl_auth, 0)) == NULL)
-		return -ENOMEM;
+	cred = rpcauth_lookupcred(NFS_CLIENT(inode)->cl_auth, 0);
+	if (IS_ERR(cred))
+		return PTR_ERR(cred);
 	ctx = alloc_nfs_open_context(filp->f_dentry, cred);
 	put_rpccred(cred);
 	if (ctx == NULL)
@@ -1613,6 +1614,12 @@ static int nfs4_fill_super(struct super_block *sb, struct nfs4_mount_data *data,
 		clnt->cl_chatty   = 1;
 		clp->cl_rpcclient = clnt;
 		clp->cl_cred = rpcauth_lookupcred(clnt->cl_auth, 0);
+		if (IS_ERR(clp->cl_cred)) {
+			up_write(&clp->cl_sem);
+			err = PTR_ERR(clp->cl_cred);
+			clp->cl_cred = NULL;
+			goto out_fail;
+		}
 		memcpy(clp->cl_ipaddr, server->ip_addr, sizeof(clp->cl_ipaddr));
 		nfs_idmap_new(clp);
 	}

fs/nfs/nfs4proc.c

@@ -774,6 +774,8 @@ nfs4_atomic_open(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
 	}
 
 	cred = rpcauth_lookupcred(NFS_SERVER(dir)->client->cl_auth, 0);
+	if (IS_ERR(cred))
+		return (struct inode *)cred;
 	state = nfs4_do_open(dir, dentry, nd->intent.open.flags, &attr, cred);
 	put_rpccred(cred);
 	if (IS_ERR(state))
@@ -789,6 +791,8 @@ nfs4_open_revalidate(struct inode *dir, struct dentry *dentry, int openflags)
 	struct inode *inode;
 
 	cred = rpcauth_lookupcred(NFS_SERVER(dir)->client->cl_auth, 0);
+	if (IS_ERR(cred))
+		return PTR_ERR(cred);
 	state = nfs4_open_delegated(dentry->d_inode, openflags, cred);
 	if (IS_ERR(state))
 		state = nfs4_do_open(dir, dentry, openflags, NULL, cred);
@@ -1009,6 +1013,8 @@ nfs4_proc_setattr(struct dentry *dentry, struct nfs_fattr *fattr,
 	
 	if (size_change) {
 		struct rpc_cred *cred = rpcauth_lookupcred(NFS_SERVER(inode)->client->cl_auth, 0);
+		if (IS_ERR(cred))
+			return PTR_ERR(cred);
 		state = nfs4_find_state(inode, cred, FMODE_WRITE);
 		if (state == NULL) {
 			state = nfs4_open_delegated(dentry->d_inode,
@@ -1324,6 +1330,8 @@ nfs4_proc_create(struct inode *dir, struct dentry *dentry, struct iattr *sattr,
 	struct rpc_cred *cred;
 
 	cred = rpcauth_lookupcred(NFS_SERVER(dir)->client->cl_auth, 0);
+	if (IS_ERR(cred))
+		return (struct inode *)cred;
 	state = nfs4_do_open(dir, dentry, flags, sattr, cred);
 	put_rpccred(cred);
 	if (IS_ERR(state)) {
@@ -2004,8 +2012,8 @@ nfs4_proc_file_open(struct inode *inode, struct file *filp)
 
 	/* Find our open stateid */
 	cred = rpcauth_lookupcred(NFS_SERVER(inode)->client->cl_auth, 0);
-	if (unlikely(cred == NULL))
-		return -ENOMEM;
+	if (IS_ERR(cred))
+		return PTR_ERR(cred);
 	ctx = alloc_nfs_open_context(dentry, cred);
 	put_rpccred(cred);
 	if (unlikely(ctx == NULL))

fs/nfs/unlink.c

@@ -167,6 +167,11 @@ nfs_async_unlink(struct dentry *dentry)
 		goto out;
 	memset(data, 0, sizeof(*data));
 
+	data->cred = rpcauth_lookupcred(clnt->cl_auth, 0);
+	if (IS_ERR(data->cred)) {
+		status = PTR_ERR(data->cred);
+		goto out_free;
+	}
 	data->dir = dget(dir);
 	data->dentry = dentry;
 
@@ -183,12 +188,14 @@ nfs_async_unlink(struct dentry *dentry)
 	spin_lock(&dentry->d_lock);
 	dentry->d_flags |= DCACHE_NFSFS_RENAMED;
 	spin_unlock(&dentry->d_lock);
-	data->cred = rpcauth_lookupcred(clnt->cl_auth, 0);
 
 	rpc_sleep_on(&nfs_delete_queue, task, NULL, NULL);
 	status = 0;
  out:
 	return status;
+out_free:
+	kfree(data);
+	return status;
 }
 
 /**

fs/nfsd/nfs4callback.c

@@ -446,7 +446,7 @@ nfsd4_probe_callback(struct nfs4_client *clp)
 	atomic_inc(&clp->cl_count);
 
 	msg.rpc_cred = nfsd4_lookupcred(clp,0);
-	if (msg.rpc_cred == NULL)
+	if (IS_ERR(msg.rpc_cred))
 		goto out_rpciod;
 	status = rpc_call_async(clnt, &msg, RPC_TASK_ASYNC, nfs4_cb_null, NULL);
 	put_rpccred(msg.rpc_cred);
@@ -512,7 +512,7 @@ nfsd4_cb_recall(struct nfs4_delegation *dp)
 		return;
 
 	msg.rpc_cred = nfsd4_lookupcred(clp, 0);
-	if (msg.rpc_cred == NULL)
+	if (IS_ERR(msg.rpc_cred))
 		goto out;
 
 	cbr->cbr_trunc = 0; /* XXX need to implement truncate optimization */

net/sunrpc/auth.c

@@ -226,12 +226,13 @@ rpcauth_lookup_credcache(struct rpc_auth *auth, struct auth_cred * acred,
 
 	if (!cred) {
 		new = auth->au_ops->crcreate(auth, acred, taskflags);
-		if (new) {
+		if (!IS_ERR(new)) {
 #ifdef RPC_DEBUG
 			new->cr_magic = RPCAUTH_CRED_MAGIC;
 #endif
 			goto retry;
-		}
+		} else
+			cred = new;
 	}
 
 	return (struct rpc_cred *) cred;
@@ -269,10 +270,11 @@ rpcauth_bindcred(struct rpc_task *task)
 
 	dprintk("RPC: %4d looking up %s cred\n",
 		task->tk_pid, task->tk_auth->au_ops->au_name);
-	task->tk_msg.rpc_cred = auth->au_ops->lookup_cred(auth, &acred, task->tk_flags);
-	if (task->tk_msg.rpc_cred == 0)
-		task->tk_status = -ENOMEM;
-	ret = task->tk_msg.rpc_cred;
+	ret = auth->au_ops->lookup_cred(auth, &acred, task->tk_flags);
+	if (!IS_ERR(ret))
+		task->tk_msg.rpc_cred = ret;
+	else
+		task->tk_status = PTR_ERR(ret);
 	put_group_info(current->group_info);
 	return ret;
 }

net/sunrpc/auth_gss/auth_gss.c

@@ -581,10 +581,11 @@ gss_pipe_downcall(struct file *filp, const char __user *src, size_t mlen)
 	} else {
 		struct auth_cred acred = { .uid = uid };
 		spin_unlock(&gss_auth->lock);
-		err = -ENOENT;
 		cred = rpcauth_lookup_credcache(clnt->cl_auth, &acred, 0);
-		if (!cred)
+		if (IS_ERR(cred)) {
+			err = PTR_ERR(cred);
 			goto err_put_ctx;
+		}
 		gss_cred_set_ctx(cred, gss_get_ctx(ctx));
 	}
 	gss_put_ctx(ctx);
@@ -791,7 +792,7 @@ gss_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int taskflags)
 out_err:
 	dprintk("RPC:      gss_create_cred failed with error %d\n", err);
 	if (cred) gss_destroy_cred(&cred->gc_base);
-	return NULL;
+	return ERR_PTR(err);
 }
 
 static int

net/sunrpc/auth_unix.c

@@ -75,7 +75,7 @@ unx_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
 				acred->uid, acred->gid);
 
 	if (!(cred = (struct unx_cred *) kmalloc(sizeof(*cred), GFP_KERNEL)))
-		return NULL;
+		return ERR_PTR(-ENOMEM);
 
 	atomic_set(&cred->uc_count, 1);
 	cred->uc_flags = RPCAUTH_CRED_UPTODATE;

net/sunrpc/clnt.c

@@ -425,9 +425,9 @@ rpc_call_setup(struct rpc_task *task, struct rpc_message *msg, int flags)
 	task->tk_msg   = *msg;
 	task->tk_flags |= flags;
 	/* Bind the user cred */
-	if (task->tk_msg.rpc_cred != NULL) {
+	if (task->tk_msg.rpc_cred != NULL)
 		rpcauth_holdcred(task);
-	} else
+	else
 		rpcauth_bindcred(task);
 
 	if (task->tk_status == 0)