1 files changed, 45 insertions, 23 deletions

diff --git a/fs/nfs/idmap.c b/fs/nfs/idmap.c
index bc3968fa81e5..c516da5873fd 100644
--- a/fs/nfs/idmap.c
+++ b/fs/nfs/idmap.c
@@ -97,7 +97,7 @@ static void nfs_fattr_free_group_name(struct nfs_fattr *fattr)
 static bool nfs_fattr_map_owner_name(struct nfs_server *server, struct nfs_fattr *fattr)
 {
 	struct nfs4_string *owner = fattr->owner_name;
-	__u32 uid;
+	kuid_t uid;
 
 	if (!(fattr->valid & NFS_ATTR_FATTR_OWNER_NAME))
 		return false;
@@ -111,7 +111,7 @@ static bool nfs_fattr_map_owner_name(struct nfs_server *server, struct nfs_fattr
 static bool nfs_fattr_map_group_name(struct nfs_server *server, struct nfs_fattr *fattr)
 {
 	struct nfs4_string *group = fattr->group_name;
-	__u32 gid;
+	kgid_t gid;
 
 	if (!(fattr->valid & NFS_ATTR_FATTR_GROUP_NAME))
 		return false;
@@ -193,7 +193,8 @@ static int nfs_idmap_init_keyring(void)
 	if (!cred)
 		return -ENOMEM;
 
-	keyring = keyring_alloc(".id_resolver", 0, 0, cred,
+	keyring = keyring_alloc(".id_resolver",
+				GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred,
 				(KEY_POS_ALL & ~KEY_POS_SETATTR) |
 				KEY_USR_VIEW | KEY_USR_READ,
 				KEY_ALLOC_NOT_IN_QUOTA, NULL);
@@ -725,9 +726,9 @@ out1:
 	return ret;
 }
 
-static int nfs_idmap_instantiate(struct key *key, struct key *authkey, char *data)
+static int nfs_idmap_instantiate(struct key *key, struct key *authkey, char *data, size_t datalen)
 {
-	return key_instantiate_and_link(key, data, strlen(data) + 1,
+	return key_instantiate_and_link(key, data, datalen,
 					id_resolver_cache->thread_keyring,
 					authkey);
 }
@@ -737,6 +738,7 @@ static int nfs_idmap_read_and_verify_message(struct idmap_msg *im,
 		struct key *key, struct key *authkey)
 {
 	char id_str[NFS_UINT_MAXLEN];
+	size_t len;
 	int ret = -ENOKEY;
 
 	/* ret = -ENOKEY */
@@ -746,13 +748,15 @@ static int nfs_idmap_read_and_verify_message(struct idmap_msg *im,
 	case IDMAP_CONV_NAMETOID:
 		if (strcmp(upcall->im_name, im->im_name) != 0)
 			break;
-		sprintf(id_str, "%d", im->im_id);
-		ret = nfs_idmap_instantiate(key, authkey, id_str);
+		/* Note: here we store the NUL terminator too */
+		len = sprintf(id_str, "%d", im->im_id) + 1;
+		ret = nfs_idmap_instantiate(key, authkey, id_str, len);
 		break;
 	case IDMAP_CONV_IDTONAME:
 		if (upcall->im_id != im->im_id)
 			break;
-		ret = nfs_idmap_instantiate(key, authkey, im->im_name);
+		len = strlen(im->im_name);
+		ret = nfs_idmap_instantiate(key, authkey, im->im_name, len);
 		break;
 	default:
 		ret = -EINVAL;
@@ -764,7 +768,7 @@ out:
 static ssize_t
 idmap_pipe_downcall(struct file *filp, const char __user *src, size_t mlen)
 {
-	struct rpc_inode *rpci = RPC_I(filp->f_path.dentry->d_inode);
+	struct rpc_inode *rpci = RPC_I(file_inode(filp));
 	struct idmap *idmap = (struct idmap *)rpci->private;
 	struct key_construction *cons;
 	struct idmap_msg im;
@@ -836,43 +840,61 @@ idmap_release_pipe(struct inode *inode)
 	nfs_idmap_abort_pipe_upcall(idmap, -EPIPE);
 }
 
-int nfs_map_name_to_uid(const struct nfs_server *server, const char *name, size_t namelen, __u32 *uid)
+int nfs_map_name_to_uid(const struct nfs_server *server, const char *name, size_t namelen, kuid_t *uid)
 {
 	struct idmap *idmap = server->nfs_client->cl_idmap;
+	__u32 id = -1;
+	int ret = 0;
 
-	if (nfs_map_string_to_numeric(name, namelen, uid))
-		return 0;
-	return nfs_idmap_lookup_id(name, namelen, "uid", uid, idmap);
+	if (!nfs_map_string_to_numeric(name, namelen, &id))
+		ret = nfs_idmap_lookup_id(name, namelen, "uid", &id, idmap);
+	if (ret == 0) {
+		*uid = make_kuid(&init_user_ns, id);
+		if (!uid_valid(*uid))
+			ret = -ERANGE;
+	}
+	return ret;
 }
 
-int nfs_map_group_to_gid(const struct nfs_server *server, const char *name, size_t namelen, __u32 *gid)
+int nfs_map_group_to_gid(const struct nfs_server *server, const char *name, size_t namelen, kgid_t *gid)
 {
 	struct idmap *idmap = server->nfs_client->cl_idmap;
+	__u32 id = -1;
+	int ret = 0;
 
-	if (nfs_map_string_to_numeric(name, namelen, gid))
-		return 0;
-	return nfs_idmap_lookup_id(name, namelen, "gid", gid, idmap);
+	if (!nfs_map_string_to_numeric(name, namelen, &id))
+		ret = nfs_idmap_lookup_id(name, namelen, "gid", &id, idmap);
+	if (ret == 0) {
+		*gid = make_kgid(&init_user_ns, id);
+		if (!gid_valid(*gid))
+			ret = -ERANGE;
+	}
+	return ret;
 }
 
-int nfs_map_uid_to_name(const struct nfs_server *server, __u32 uid, char *buf, size_t buflen)
+int nfs_map_uid_to_name(const struct nfs_server *server, kuid_t uid, char *buf, size_t buflen)
 {
 	struct idmap *idmap = server->nfs_client->cl_idmap;
 	int ret = -EINVAL;
+	__u32 id;
 
+	id = from_kuid(&init_user_ns, uid);
 	if (!(server->caps & NFS_CAP_UIDGID_NOMAP))
-		ret = nfs_idmap_lookup_name(uid, "user", buf, buflen, idmap);
+		ret = nfs_idmap_lookup_name(id, "user", buf, buflen, idmap);
 	if (ret < 0)
-		ret = nfs_map_numeric_to_string(uid, buf, buflen);
+		ret = nfs_map_numeric_to_string(id, buf, buflen);
 	return ret;
 }
-int nfs_map_gid_to_group(const struct nfs_server *server, __u32 gid, char *buf, size_t buflen)
+int nfs_map_gid_to_group(const struct nfs_server *server, kgid_t gid, char *buf, size_t buflen)
 {
 	struct idmap *idmap = server->nfs_client->cl_idmap;
 	int ret = -EINVAL;
+	__u32 id;
 
+	id = from_kgid(&init_user_ns, gid);
 	if (!(server->caps & NFS_CAP_UIDGID_NOMAP))
-		ret = nfs_idmap_lookup_name(gid, "group", buf, buflen, idmap);
+		ret = nfs_idmap_lookup_name(id, "group", buf, buflen, idmap);
 	if (ret < 0)
-		ret = nfs_map_numeric_to_string(gid, buf, buflen);
+		ret = nfs_map_numeric_to_string(id, buf, buflen);
 	return ret;
 }