/*
* On success:
* fills dentry object appropriate values and returns NULL.
* On fail (== error)
* returns error ptr
*
* @dir : Parent inode. It is locked (dir->i_mutex)
* @dentry : Target dentry to lookup. we should set each of fields.
* (dentry->d_name is initialized already)
* @nd : nameidata of parent inode
*/
struct dentry *sdcardfs_lookup(struct inode *dir, struct dentry *dentry,
unsigned int flags)
{
struct dentry *ret = NULL, *parent;
struct path lower_parent_path;
int err = 0;
struct sdcardfs_sb_info *sbi = SDCARDFS_SB(dentry->d_sb);
const struct cred *saved_cred = NULL;
parent = dget_parent(dentry);
if(!check_caller_access_to_name(parent->d_inode, dentry->d_name.name,
sbi->options.derive, 0, 0)) {
ret = ERR_PTR(-EACCES);
printk(KERN_INFO "%s: need to check the caller's gid in packages.list\n"
" dentry: %s, task:%s\n",
__func__, dentry->d_name.name, current->comm);
goto out_err;
}
/* save current_cred and override it */
OVERRIDE_CRED_PTR(SDCARDFS_SB(dir->i_sb), saved_cred);
sdcardfs_get_lower_path(parent, &lower_parent_path);
/* allocate dentry private data. We free it in ->d_release */
err = new_dentry_private_data(dentry);
if (err) {
ret = ERR_PTR(err);
goto out;
}
ret = __sdcardfs_lookup(dentry, flags, &lower_parent_path);
if (IS_ERR(ret))
{
goto out;
}
if (ret)
dentry = ret;
if (dentry->d_inode) {
fsstack_copy_attr_times(dentry->d_inode,
sdcardfs_lower_inode(dentry->d_inode));
/* get drived permission */
get_derived_permission(parent, dentry);
fix_derived_permission(dentry->d_inode);
}
/* update parent directory's atime */
fsstack_copy_attr_atime(parent->d_inode,
sdcardfs_lower_inode(parent->d_inode));
out:
sdcardfs_put_lower_path(parent, &lower_parent_path);
REVERT_CRED(saved_cred);
out_err:
dput(parent);
return ret;
}
/*
* On success:
* fills dentry object appropriate values and returns NULL.
* On fail (== error)
* returns error ptr
*
* @dir : Parent inode. It is locked (dir->i_mutex)
* @dentry : Target dentry to lookup. we should set each of fields.
* (dentry->d_name is initialized already)
* @nd : nameidata of parent inode
*/
struct dentry *sdcardfs_lookup(struct inode *dir, struct dentry *dentry,
struct nameidata *nd)
{
struct dentry *ret, *parent;
struct path lower_parent_path;
int err = 0;
OVERRIDE_CRED_PTR(SDCARDFS_SB(dir->i_sb));
parent = dget_parent(dentry);
sdcardfs_get_lower_path(parent, &lower_parent_path);
/* allocate dentry private data. We free it in ->d_release */
err = new_dentry_private_data(dentry);
if (err) {
ret = ERR_PTR(err);
goto out;
}
ret = __sdcardfs_lookup(dentry, nd, &lower_parent_path);
if (IS_ERR(ret))
{
goto out;
}
if (ret)
dentry = ret;
if (dentry->d_inode)
fsstack_copy_attr_times(dentry->d_inode,
sdcardfs_lower_inode(dentry->d_inode));
/* update parent directory's atime */
fsstack_copy_attr_atime(parent->d_inode,
sdcardfs_lower_inode(parent->d_inode));
out:
sdcardfs_put_lower_path(parent, &lower_parent_path);
dput(parent);
REVERT_CRED();
return ret;
}
