configfs: Add permission and ownership to configfs objects.

configfs always made item and attribute ownership root.root and
permissions based on a umask of 022.  Add ->setattr() to allow
chown(2)/chmod(2), and persist the changes for the lifetime of the
items and attributes.

Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
This commit is contained in:
Joel Becker
2006-01-25 13:31:07 -08:00
committed by Mark Fasheh
parent 62ca3d2603
commit 3d0f89bb16
8 changed files with 181 additions and 39 deletions

View File

@@ -31,6 +31,7 @@
#include <linux/pagemap.h>
#include <linux/namei.h>
#include <linux/backing-dev.h>
#include <linux/capability.h>
#include <linux/configfs.h>
#include "configfs_internal.h"
@@ -48,18 +49,107 @@ static struct backing_dev_info configfs_backing_dev_info = {
.capabilities = BDI_CAP_NO_ACCT_DIRTY | BDI_CAP_NO_WRITEBACK,
};
struct inode * configfs_new_inode(mode_t mode)
static struct inode_operations configfs_inode_operations ={
.setattr = configfs_setattr,
};
int configfs_setattr(struct dentry * dentry, struct iattr * iattr)
{
struct inode * inode = dentry->d_inode;
struct configfs_dirent * sd = dentry->d_fsdata;
struct iattr * sd_iattr;
unsigned int ia_valid = iattr->ia_valid;
int error;
if (!sd)
return -EINVAL;
sd_iattr = sd->s_iattr;
error = inode_change_ok(inode, iattr);
if (error)
return error;
error = inode_setattr(inode, iattr);
if (error)
return error;
if (!sd_iattr) {
/* setting attributes for the first time, allocate now */
sd_iattr = kmalloc(sizeof(struct iattr), GFP_KERNEL);
if (!sd_iattr)
return -ENOMEM;
/* assign default attributes */
memset(sd_iattr, 0, sizeof(struct iattr));
sd_iattr->ia_mode = sd->s_mode;
sd_iattr->ia_uid = 0;
sd_iattr->ia_gid = 0;
sd_iattr->ia_atime = sd_iattr->ia_mtime = sd_iattr->ia_ctime = CURRENT_TIME;
sd->s_iattr = sd_iattr;
}
/* attributes were changed atleast once in past */
if (ia_valid & ATTR_UID)
sd_iattr->ia_uid = iattr->ia_uid;
if (ia_valid & ATTR_GID)
sd_iattr->ia_gid = iattr->ia_gid;
if (ia_valid & ATTR_ATIME)
sd_iattr->ia_atime = timespec_trunc(iattr->ia_atime,
inode->i_sb->s_time_gran);
if (ia_valid & ATTR_MTIME)
sd_iattr->ia_mtime = timespec_trunc(iattr->ia_mtime,
inode->i_sb->s_time_gran);
if (ia_valid & ATTR_CTIME)
sd_iattr->ia_ctime = timespec_trunc(iattr->ia_ctime,
inode->i_sb->s_time_gran);
if (ia_valid & ATTR_MODE) {
umode_t mode = iattr->ia_mode;
if (!in_group_p(inode->i_gid) && !capable(CAP_FSETID))
mode &= ~S_ISGID;
sd_iattr->ia_mode = sd->s_mode = mode;
}
return error;
}
static inline void set_default_inode_attr(struct inode * inode, mode_t mode)
{
inode->i_mode = mode;
inode->i_uid = 0;
inode->i_gid = 0;
inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
}
static inline void set_inode_attr(struct inode * inode, struct iattr * iattr)
{
inode->i_mode = iattr->ia_mode;
inode->i_uid = iattr->ia_uid;
inode->i_gid = iattr->ia_gid;
inode->i_atime = iattr->ia_atime;
inode->i_mtime = iattr->ia_mtime;
inode->i_ctime = iattr->ia_ctime;
}
struct inode * configfs_new_inode(mode_t mode, struct configfs_dirent * sd)
{
struct inode * inode = new_inode(configfs_sb);
if (inode) {
inode->i_mode = mode;
inode->i_uid = 0;
inode->i_gid = 0;
inode->i_blksize = PAGE_CACHE_SIZE;
inode->i_blocks = 0;
inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
inode->i_mapping->a_ops = &configfs_aops;
inode->i_mapping->backing_dev_info = &configfs_backing_dev_info;
inode->i_op = &configfs_inode_operations;
if (sd->s_iattr) {
/* sysfs_dirent has non-default attributes
* get them for the new inode from persistent copy
* in sysfs_dirent
*/
set_inode_attr(inode, sd->s_iattr);
} else
set_default_inode_attr(inode, mode);
}
return inode;
}
@@ -70,7 +160,8 @@ int configfs_create(struct dentry * dentry, int mode, int (*init)(struct inode *
struct inode * inode = NULL;
if (dentry) {
if (!dentry->d_inode) {
if ((inode = configfs_new_inode(mode))) {
struct configfs_dirent *sd = dentry->d_fsdata;
if ((inode = configfs_new_inode(mode, sd))) {
if (dentry->d_parent && dentry->d_parent->d_inode) {
struct inode *p_inode = dentry->d_parent->d_inode;
p_inode->i_mtime = p_inode->i_ctime = CURRENT_TIME;
@@ -103,7 +194,7 @@ int configfs_create(struct dentry * dentry, int mode, int (*init)(struct inode *
*/
const unsigned char * configfs_get_name(struct configfs_dirent *sd)
{
struct attribute * attr;
struct configfs_attribute *attr;
if (!sd || !sd->s_element)
BUG();
@@ -114,7 +205,7 @@ const unsigned char * configfs_get_name(struct configfs_dirent *sd)
if (sd->s_type & CONFIGFS_ITEM_ATTR) {
attr = sd->s_element;
return attr->name;
return attr->ca_name;
}
return NULL;
}
@@ -130,13 +221,17 @@ void configfs_drop_dentry(struct configfs_dirent * sd, struct dentry * parent)
if (dentry) {
spin_lock(&dcache_lock);
spin_lock(&dentry->d_lock);
if (!(d_unhashed(dentry) && dentry->d_inode)) {
dget_locked(dentry);
__d_drop(dentry);
spin_unlock(&dentry->d_lock);
spin_unlock(&dcache_lock);
simple_unlink(parent->d_inode, dentry);
} else
} else {
spin_unlock(&dentry->d_lock);
spin_unlock(&dcache_lock);
}
}
}
@@ -145,6 +240,10 @@ void configfs_hash_and_remove(struct dentry * dir, const char * name)
struct configfs_dirent * sd;
struct configfs_dirent * parent_sd = dir->d_fsdata;
if (dir->d_inode == NULL)
/* no inode means this hasn't been made visible yet */
return;
mutex_lock(&dir->d_inode->i_mutex);
list_for_each_entry(sd, &parent_sd->s_children, s_sibling) {
if (!sd->s_element)