linux/fs/ntfs3/namei.c
Konstantin Komarov 911daf695a
fs/ntfs3: Fix formatting, change comments, renaming
Huacai Chen:
	The label end_reply is obviously a typo. It should be "replay" in this
	context. So rename end_reply to end_replay.

Suggested-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
2024-07-11 12:19:46 +03:00

528 lines
11 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
*
* Copyright (C) 2019-2021 Paragon Software GmbH, All rights reserved.
*
*/
#include <linux/fs.h>
#include <linux/nls.h>
#include <linux/ctype.h>
#include <linux/posix_acl.h>
#include "debug.h"
#include "ntfs.h"
#include "ntfs_fs.h"
/*
* fill_name_de - Format NTFS_DE in @buf.
*/
int fill_name_de(struct ntfs_sb_info *sbi, void *buf, const struct qstr *name,
const struct cpu_str *uni)
{
int err;
struct NTFS_DE *e = buf;
u16 data_size;
struct ATTR_FILE_NAME *fname = (struct ATTR_FILE_NAME *)(e + 1);
#ifndef CONFIG_NTFS3_64BIT_CLUSTER
e->ref.high = fname->home.high = 0;
#endif
if (uni) {
#ifdef __BIG_ENDIAN
int ulen = uni->len;
__le16 *uname = fname->name;
const u16 *name_cpu = uni->name;
while (ulen--)
*uname++ = cpu_to_le16(*name_cpu++);
#else
memcpy(fname->name, uni->name, uni->len * sizeof(u16));
#endif
fname->name_len = uni->len;
} else {
/* Convert input string to unicode. */
err = ntfs_nls_to_utf16(sbi, name->name, name->len,
(struct cpu_str *)&fname->name_len,
NTFS_NAME_LEN, UTF16_LITTLE_ENDIAN);
if (err < 0)
return err;
}
fname->type = FILE_NAME_POSIX;
data_size = fname_full_size(fname);
e->size = cpu_to_le16(ALIGN(data_size, 8) + sizeof(struct NTFS_DE));
e->key_size = cpu_to_le16(data_size);
e->flags = 0;
e->res = 0;
return 0;
}
/*
* ntfs_lookup - inode_operations::lookup
*/
static struct dentry *ntfs_lookup(struct inode *dir, struct dentry *dentry,
u32 flags)
{
struct ntfs_inode *ni = ntfs_i(dir);
struct cpu_str *uni = __getname();
struct inode *inode;
int err;
if (!uni)
inode = ERR_PTR(-ENOMEM);
else {
err = ntfs_nls_to_utf16(ni->mi.sbi, dentry->d_name.name,
dentry->d_name.len, uni, NTFS_NAME_LEN,
UTF16_HOST_ENDIAN);
if (err < 0)
inode = ERR_PTR(err);
else {
ni_lock(ni);
inode = dir_search_u(dir, uni, NULL);
ni_unlock(ni);
}
__putname(uni);
}
/*
* Check for a null pointer
* If the MFT record of ntfs inode is not a base record, inode->i_op can be NULL.
* This causes null pointer dereference in d_splice_alias().
*/
if (!IS_ERR_OR_NULL(inode) && !inode->i_op) {
iput(inode);
inode = ERR_PTR(-EINVAL);
}
return d_splice_alias(inode, dentry);
}
/*
* ntfs_create - inode_operations::create
*/
static int ntfs_create(struct mnt_idmap *idmap, struct inode *dir,
struct dentry *dentry, umode_t mode, bool excl)
{
return ntfs_create_inode(idmap, dir, dentry, NULL, S_IFREG | mode, 0,
NULL, 0, NULL);
}
/*
* ntfs_mknod - inode_operations::mknod
*/
static int ntfs_mknod(struct mnt_idmap *idmap, struct inode *dir,
struct dentry *dentry, umode_t mode, dev_t rdev)
{
return ntfs_create_inode(idmap, dir, dentry, NULL, mode, rdev, NULL, 0,
NULL);
}
/*
* ntfs_link - inode_operations::link
*/
static int ntfs_link(struct dentry *ode, struct inode *dir, struct dentry *de)
{
int err;
struct inode *inode = d_inode(ode);
struct ntfs_inode *ni = ntfs_i(inode);
if (S_ISDIR(inode->i_mode))
return -EPERM;
if (inode->i_nlink >= NTFS_LINK_MAX)
return -EMLINK;
ni_lock_dir(ntfs_i(dir));
if (inode != dir)
ni_lock(ni);
inc_nlink(inode);
ihold(inode);
err = ntfs_link_inode(inode, de);
if (!err) {
inode_set_ctime_current(inode);
inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir));
mark_inode_dirty(inode);
mark_inode_dirty(dir);
d_instantiate(de, inode);
} else {
drop_nlink(inode);
iput(inode);
}
if (inode != dir)
ni_unlock(ni);
ni_unlock(ntfs_i(dir));
return err;
}
/*
* ntfs_unlink - inode_operations::unlink
*/
static int ntfs_unlink(struct inode *dir, struct dentry *dentry)
{
struct ntfs_inode *ni = ntfs_i(dir);
int err;
if (unlikely(ntfs3_forced_shutdown(dir->i_sb)))
return -EIO;
ni_lock_dir(ni);
err = ntfs_unlink_inode(dir, dentry);
ni_unlock(ni);
return err;
}
/*
* ntfs_symlink - inode_operations::symlink
*/
static int ntfs_symlink(struct mnt_idmap *idmap, struct inode *dir,
struct dentry *dentry, const char *symname)
{
u32 size = strlen(symname);
if (unlikely(ntfs3_forced_shutdown(dir->i_sb)))
return -EIO;
return ntfs_create_inode(idmap, dir, dentry, NULL, S_IFLNK | 0777, 0,
symname, size, NULL);
}
/*
* ntfs_mkdir- inode_operations::mkdir
*/
static int ntfs_mkdir(struct mnt_idmap *idmap, struct inode *dir,
struct dentry *dentry, umode_t mode)
{
return ntfs_create_inode(idmap, dir, dentry, NULL, S_IFDIR | mode, 0,
NULL, 0, NULL);
}
/*
* ntfs_rmdir - inode_operations::rmdir
*/
static int ntfs_rmdir(struct inode *dir, struct dentry *dentry)
{
struct ntfs_inode *ni = ntfs_i(dir);
int err;
if (unlikely(ntfs3_forced_shutdown(dir->i_sb)))
return -EIO;
ni_lock_dir(ni);
err = ntfs_unlink_inode(dir, dentry);
ni_unlock(ni);
return err;
}
/*
* ntfs_rename - inode_operations::rename
*/
static int ntfs_rename(struct mnt_idmap *idmap, struct inode *dir,
struct dentry *dentry, struct inode *new_dir,
struct dentry *new_dentry, u32 flags)
{
int err;
struct super_block *sb = dir->i_sb;
struct ntfs_sb_info *sbi = sb->s_fs_info;
struct ntfs_inode *dir_ni = ntfs_i(dir);
struct ntfs_inode *new_dir_ni = ntfs_i(new_dir);
struct inode *inode = d_inode(dentry);
struct ntfs_inode *ni = ntfs_i(inode);
struct inode *new_inode = d_inode(new_dentry);
struct NTFS_DE *de, *new_de;
bool is_same, is_bad;
/*
* de - memory of PATH_MAX bytes:
* [0-1024) - original name (dentry->d_name)
* [1024-2048) - paired to original name, usually DOS variant of dentry->d_name
* [2048-3072) - new name (new_dentry->d_name)
*/
static_assert(SIZEOF_ATTRIBUTE_FILENAME_MAX + SIZEOF_RESIDENT < 1024);
static_assert(SIZEOF_ATTRIBUTE_FILENAME_MAX + sizeof(struct NTFS_DE) <
1024);
static_assert(PATH_MAX >= 4 * 1024);
if (unlikely(ntfs3_forced_shutdown(sb)))
return -EIO;
if (flags & ~RENAME_NOREPLACE)
return -EINVAL;
is_same = dentry->d_name.len == new_dentry->d_name.len &&
!memcmp(dentry->d_name.name, new_dentry->d_name.name,
dentry->d_name.len);
if (is_same && dir == new_dir) {
/* Nothing to do. */
return 0;
}
if (ntfs_is_meta_file(sbi, inode->i_ino)) {
/* Should we print an error? */
return -EINVAL;
}
if (new_inode) {
/* Target name exists. Unlink it. */
dget(new_dentry);
ni_lock_dir(new_dir_ni);
err = ntfs_unlink_inode(new_dir, new_dentry);
ni_unlock(new_dir_ni);
dput(new_dentry);
if (err)
return err;
}
/* Allocate PATH_MAX bytes. */
de = __getname();
if (!de)
return -ENOMEM;
/* Translate dentry->d_name into unicode form. */
err = fill_name_de(sbi, de, &dentry->d_name, NULL);
if (err < 0)
goto out;
if (is_same) {
/* Reuse 'de'. */
new_de = de;
} else {
/* Translate new_dentry->d_name into unicode form. */
new_de = Add2Ptr(de, 2048);
err = fill_name_de(sbi, new_de, &new_dentry->d_name, NULL);
if (err < 0)
goto out;
}
ni_lock_dir(dir_ni);
ni_lock(ni);
if (dir_ni != new_dir_ni)
ni_lock_dir2(new_dir_ni);
is_bad = false;
err = ni_rename(dir_ni, new_dir_ni, ni, de, new_de, &is_bad);
if (is_bad) {
/* Restore after failed rename failed too. */
_ntfs_bad_inode(inode);
} else if (!err) {
simple_rename_timestamp(dir, dentry, new_dir, new_dentry);
mark_inode_dirty(inode);
mark_inode_dirty(dir);
if (dir != new_dir)
mark_inode_dirty(new_dir);
if (IS_DIRSYNC(dir))
ntfs_sync_inode(dir);
if (IS_DIRSYNC(new_dir))
ntfs_sync_inode(inode);
}
if (dir_ni != new_dir_ni)
ni_unlock(new_dir_ni);
ni_unlock(ni);
ni_unlock(dir_ni);
out:
__putname(de);
return err;
}
struct dentry *ntfs3_get_parent(struct dentry *child)
{
struct inode *inode = d_inode(child);
struct ntfs_inode *ni = ntfs_i(inode);
struct ATTR_LIST_ENTRY *le = NULL;
struct ATTRIB *attr = NULL;
struct ATTR_FILE_NAME *fname;
while ((attr = ni_find_attr(ni, attr, &le, ATTR_NAME, NULL, 0, NULL,
NULL))) {
fname = resident_data_ex(attr, SIZEOF_ATTRIBUTE_FILENAME);
if (!fname)
continue;
return d_obtain_alias(
ntfs_iget5(inode->i_sb, &fname->home, NULL));
}
return ERR_PTR(-ENOENT);
}
/*
* dentry_operations::d_hash
*/
static int ntfs_d_hash(const struct dentry *dentry, struct qstr *name)
{
struct ntfs_sb_info *sbi;
const char *n = name->name;
unsigned int len = name->len;
unsigned long hash;
struct cpu_str *uni;
unsigned int c;
int err;
/* First try fast implementation. */
hash = init_name_hash(dentry);
for (;;) {
if (!len--) {
name->hash = end_name_hash(hash);
return 0;
}
c = *n++;
if (c >= 0x80)
break;
hash = partial_name_hash(toupper(c), hash);
}
/*
* Try slow way with current upcase table
*/
uni = __getname();
if (!uni)
return -ENOMEM;
sbi = dentry->d_sb->s_fs_info;
err = ntfs_nls_to_utf16(sbi, name->name, name->len, uni, NTFS_NAME_LEN,
UTF16_HOST_ENDIAN);
if (err < 0)
goto out;
if (!err) {
err = -EINVAL;
goto out;
}
hash = ntfs_names_hash(uni->name, uni->len, sbi->upcase,
init_name_hash(dentry));
name->hash = end_name_hash(hash);
err = 0;
out:
__putname(uni);
return err;
}
/*
* dentry_operations::d_compare
*/
static int ntfs_d_compare(const struct dentry *dentry, unsigned int len1,
const char *str, const struct qstr *name)
{
struct ntfs_sb_info *sbi;
int ret;
const char *n1 = str;
const char *n2 = name->name;
unsigned int len2 = name->len;
unsigned int lm = min(len1, len2);
unsigned char c1, c2;
struct cpu_str *uni1;
struct le_str *uni2;
/* First try fast implementation. */
for (;;) {
if (!lm--)
return len1 != len2;
if ((c1 = *n1++) == (c2 = *n2++))
continue;
if (c1 >= 0x80 || c2 >= 0x80)
break;
if (toupper(c1) != toupper(c2))
return 1;
}
/*
* Try slow way with current upcase table
*/
sbi = dentry->d_sb->s_fs_info;
uni1 = __getname();
if (!uni1)
return -ENOMEM;
ret = ntfs_nls_to_utf16(sbi, str, len1, uni1, NTFS_NAME_LEN,
UTF16_HOST_ENDIAN);
if (ret < 0)
goto out;
if (!ret) {
ret = -EINVAL;
goto out;
}
uni2 = Add2Ptr(uni1, 2048);
ret = ntfs_nls_to_utf16(sbi, name->name, name->len,
(struct cpu_str *)uni2, NTFS_NAME_LEN,
UTF16_LITTLE_ENDIAN);
if (ret < 0)
goto out;
if (!ret) {
ret = -EINVAL;
goto out;
}
ret = !ntfs_cmp_names_cpu(uni1, uni2, sbi->upcase, false) ? 0 : 1;
out:
__putname(uni1);
return ret;
}
// clang-format off
const struct inode_operations ntfs_dir_inode_operations = {
.lookup = ntfs_lookup,
.create = ntfs_create,
.link = ntfs_link,
.unlink = ntfs_unlink,
.symlink = ntfs_symlink,
.mkdir = ntfs_mkdir,
.rmdir = ntfs_rmdir,
.mknod = ntfs_mknod,
.rename = ntfs_rename,
.get_acl = ntfs_get_acl,
.set_acl = ntfs_set_acl,
.setattr = ntfs3_setattr,
.getattr = ntfs_getattr,
.listxattr = ntfs_listxattr,
.fiemap = ntfs_fiemap,
.fileattr_get = ntfs_fileattr_get,
.fileattr_set = ntfs_fileattr_set,
};
const struct inode_operations ntfs_special_inode_operations = {
.setattr = ntfs3_setattr,
.getattr = ntfs_getattr,
.listxattr = ntfs_listxattr,
.get_acl = ntfs_get_acl,
.set_acl = ntfs_set_acl,
};
const struct dentry_operations ntfs_dentry_ops = {
.d_hash = ntfs_d_hash,
.d_compare = ntfs_d_compare,
};
// clang-format on