linux-imx

/*

 *

 * Copyright (C) 2011 Novell Inc.

 *

 * This program is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 as published by

 * the Free Software Foundation.

 */

​

#include <linux/module.h>

#include <linux/fs.h>

#include <linux/slab.h>

#include <linux/file.h>

#include <linux/splice.h>

#include <linux/xattr.h>

#include <linux/security.h>

#include <linux/uaccess.h>

#include <linux/sched/signal.h>

#include <linux/cred.h>

#include <linux/namei.h>

#include <linux/fdtable.h>

#include <linux/ratelimit.h>

#include <linux/exportfs.h>

#include "overlayfs.h"

​

#define OVL_COPY_UP_CHUNK_SIZE (1 << 20)

​

static int ovl_ccup_set(const char *buf, const struct kernel_param *param)

{

    pr_warn("overlayfs: \"check_copy_up\" module option is obsolete\n");

    return 0;

}

​

static int ovl_ccup_get(char *buf, const struct kernel_param *param)

{

    return sprintf(buf, "N\n");

}

​

module_param_call(check_copy_up, ovl_ccup_set, ovl_ccup_get, NULL, 0644);

MODULE_PARM_DESC(ovl_check_copy_up, "Obsolete; does nothing");

​

int ovl_copy_xattr(struct dentry *old, struct dentry *new)

{

    ssize_t list_size, size, value_size = 0;

    char *buf, *name, *value = NULL;

    int uninitialized_var(error);

    size_t slen;

​

    if (!(old->d_inode->i_opflags & IOP_XATTR) ||

        !(new->d_inode->i_opflags & IOP_XATTR))

        return 0;

​

    list_size = vfs_listxattr(old, NULL, 0);

    if (list_size <= 0) {

        if (list_size == -EOPNOTSUPP)

            return 0;

        return list_size;

    }

​

    buf = kzalloc(list_size, GFP_KERNEL);

    if (!buf)

        return -ENOMEM;

​

    list_size = vfs_listxattr(old, buf, list_size);

    if (list_size <= 0) {

        error = list_size;

        goto out;

    }

​

    for (name = buf; list_size; name += slen) {

        slen = strnlen(name, list_size) + 1;

​

        /* underlying fs providing us with an broken xattr list? */

        if (WARN_ON(slen > list_size)) {

            error = -EIO;

            break;

        }

        list_size -= slen;

​

        if (ovl_is_private_xattr(name))

            continue;

retry:

        size = vfs_getxattr(old, name, value, value_size);

        if (size == -ERANGE)

            size = vfs_getxattr(old, name, NULL, 0);

​

        if (size < 0) {

            error = size;

            break;

        }

​

        if (size > value_size) {