linux-stable/fs/f2fs/namei.c
Eric Biggers 4d6d4ed175 fscrypt: return -EXDEV for incompatible rename or link into encrypted dir
commit f5e55e777c upstream.

Currently, trying to rename or link a regular file, directory, or
symlink into an encrypted directory fails with EPERM when the source
file is unencrypted or is encrypted with a different encryption policy,
and is on the same mountpoint.  It is correct for the operation to fail,
but the choice of EPERM breaks tools like 'mv' that know to copy rather
than rename if they see EXDEV, but don't know what to do with EPERM.

Our original motivation for EPERM was to encourage users to securely
handle their data.  Encrypting files by "moving" them into an encrypted
directory can be insecure because the unencrypted data may remain in
free space on disk, where it can later be recovered by an attacker.
It's much better to encrypt the data from the start, or at least try to
securely delete the source data e.g. using the 'shred' program.

However, the current behavior hasn't been effective at achieving its
goal because users tend to be confused, hack around it, and complain;
see e.g. https://github.com/google/fscrypt/issues/76.  And in some cases
it's actually inconsistent or unnecessary.  For example, 'mv'-ing files
between differently encrypted directories doesn't work even in cases
where it can be secure, such as when in userspace the same passphrase
protects both directories.  Yet, you *can* already 'mv' unencrypted
files into an encrypted directory if the source files are on a different
mountpoint, even though doing so is often insecure.

There are probably better ways to teach users to securely handle their
files.  For example, the 'fscrypt' userspace tool could provide a
command that migrates unencrypted files into an encrypted directory,
acting like 'shred' on the source files and providing appropriate
warnings depending on the type of the source filesystem and disk.

Receiving errors on unimportant files might also force some users to
disable encryption, thus making the behavior counterproductive.  It's
desirable to make encryption as unobtrusive as possible.

Therefore, change the error code from EPERM to EXDEV so that tools
looking for EXDEV will fall back to a copy.

This, of course, doesn't prevent users from still doing the right things
to securely manage their files.  Note that this also matches the
behavior when a file is renamed between two project quota hierarchies;
so there's precedent for using EXDEV for things other than mountpoints.

xfstests generic/398 will require an update with this change.

[Rewritten from an earlier patch series by Michael Halcrow.]

Cc: Michael Halcrow <mhalcrow@google.com>
Cc: Joe Richey <joerichey@google.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-05 11:06:52 +01:00

1222 lines
28 KiB
C

/*
* fs/f2fs/namei.c
*
* Copyright (c) 2012 Samsung Electronics Co., Ltd.
* http://www.samsung.com/
*
* 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/fs.h>
#include <linux/f2fs_fs.h>
#include <linux/pagemap.h>
#include <linux/sched.h>
#include <linux/ctype.h>
#include <linux/dcache.h>
#include <linux/namei.h>
#include <linux/quotaops.h>
#include "f2fs.h"
#include "node.h"
#include "xattr.h"
#include "acl.h"
#include <trace/events/f2fs.h>
static struct inode *f2fs_new_inode(struct inode *dir, umode_t mode)
{
struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
nid_t ino;
struct inode *inode;
bool nid_free = false;
int err;
inode = new_inode(dir->i_sb);
if (!inode)
return ERR_PTR(-ENOMEM);
f2fs_lock_op(sbi);
if (!alloc_nid(sbi, &ino)) {
f2fs_unlock_op(sbi);
err = -ENOSPC;
goto fail;
}
f2fs_unlock_op(sbi);
nid_free = true;
inode_init_owner(inode, dir, mode);
inode->i_ino = ino;
inode->i_blocks = 0;
inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
inode->i_generation = sbi->s_next_generation++;
err = insert_inode_locked(inode);
if (err) {
err = -EINVAL;
goto fail;
}
if (f2fs_sb_has_project_quota(sbi->sb) &&
(F2FS_I(dir)->i_flags & FS_PROJINHERIT_FL))
F2FS_I(inode)->i_projid = F2FS_I(dir)->i_projid;
else
F2FS_I(inode)->i_projid = make_kprojid(&init_user_ns,
F2FS_DEF_PROJID);
err = dquot_initialize(inode);
if (err)
goto fail_drop;
err = dquot_alloc_inode(inode);
if (err)
goto fail_drop;
/* If the directory encrypted, then we should encrypt the inode. */
if (f2fs_encrypted_inode(dir) && f2fs_may_encrypt(inode))
f2fs_set_encrypted_inode(inode);
set_inode_flag(inode, FI_NEW_INODE);
if (f2fs_sb_has_extra_attr(sbi->sb)) {
set_inode_flag(inode, FI_EXTRA_ATTR);
F2FS_I(inode)->i_extra_isize = F2FS_TOTAL_EXTRA_ATTR_SIZE;
}
if (test_opt(sbi, INLINE_XATTR))
set_inode_flag(inode, FI_INLINE_XATTR);
if (test_opt(sbi, INLINE_DATA) && f2fs_may_inline_data(inode))
set_inode_flag(inode, FI_INLINE_DATA);
if (f2fs_may_inline_dentry(inode))
set_inode_flag(inode, FI_INLINE_DENTRY);
f2fs_init_extent_tree(inode, NULL);
stat_inc_inline_xattr(inode);
stat_inc_inline_inode(inode);
stat_inc_inline_dir(inode);
F2FS_I(inode)->i_flags =
f2fs_mask_flags(mode, F2FS_I(dir)->i_flags & F2FS_FL_INHERITED);
if (S_ISDIR(inode->i_mode))
F2FS_I(inode)->i_flags |= FS_INDEX_FL;
if (F2FS_I(inode)->i_flags & FS_PROJINHERIT_FL)
set_inode_flag(inode, FI_PROJ_INHERIT);
trace_f2fs_new_inode(inode, 0);
return inode;
fail:
trace_f2fs_new_inode(inode, err);
make_bad_inode(inode);
if (nid_free)
set_inode_flag(inode, FI_FREE_NID);
iput(inode);
return ERR_PTR(err);
fail_drop:
trace_f2fs_new_inode(inode, err);
dquot_drop(inode);
inode->i_flags |= S_NOQUOTA;
if (nid_free)
set_inode_flag(inode, FI_FREE_NID);
clear_nlink(inode);
unlock_new_inode(inode);
iput(inode);
return ERR_PTR(err);
}
static int is_multimedia_file(const unsigned char *s, const char *sub)
{
size_t slen = strlen(s);
size_t sublen = strlen(sub);
int i;
/*
* filename format of multimedia file should be defined as:
* "filename + '.' + extension + (optional: '.' + temp extension)".
*/
if (slen < sublen + 2)
return 0;
for (i = 1; i < slen - sublen; i++) {
if (s[i] != '.')
continue;
if (!strncasecmp(s + i + 1, sub, sublen))
return 1;
}
return 0;
}
/*
* Set multimedia files as cold files for hot/cold data separation
*/
static inline void set_cold_files(struct f2fs_sb_info *sbi, struct inode *inode,
const unsigned char *name)
{
int i;
__u8 (*extlist)[8] = sbi->raw_super->extension_list;
int count = le32_to_cpu(sbi->raw_super->extension_count);
for (i = 0; i < count; i++) {
if (is_multimedia_file(name, extlist[i])) {
file_set_cold(inode);
break;
}
}
}
static int f2fs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
bool excl)
{
struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
struct inode *inode;
nid_t ino = 0;
int err;
err = dquot_initialize(dir);
if (err)
return err;
inode = f2fs_new_inode(dir, mode);
if (IS_ERR(inode))
return PTR_ERR(inode);
if (!test_opt(sbi, DISABLE_EXT_IDENTIFY))
set_cold_files(sbi, inode, dentry->d_name.name);
inode->i_op = &f2fs_file_inode_operations;
inode->i_fop = &f2fs_file_operations;
inode->i_mapping->a_ops = &f2fs_dblock_aops;
ino = inode->i_ino;
f2fs_lock_op(sbi);
err = f2fs_add_link(dentry, inode);
if (err)
goto out;
f2fs_unlock_op(sbi);
alloc_nid_done(sbi, ino);
d_instantiate_new(dentry, inode);
if (IS_DIRSYNC(dir))
f2fs_sync_fs(sbi->sb, 1);
f2fs_balance_fs(sbi, true);
return 0;
out:
handle_failed_inode(inode);
return err;
}
static int f2fs_link(struct dentry *old_dentry, struct inode *dir,
struct dentry *dentry)
{
struct inode *inode = d_inode(old_dentry);
struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
int err;
if (f2fs_encrypted_inode(dir) &&
!fscrypt_has_permitted_context(dir, inode))
return -EXDEV;
if (is_inode_flag_set(dir, FI_PROJ_INHERIT) &&
(!projid_eq(F2FS_I(dir)->i_projid,
F2FS_I(old_dentry->d_inode)->i_projid)))
return -EXDEV;
err = dquot_initialize(dir);
if (err)
return err;
f2fs_balance_fs(sbi, true);
inode->i_ctime = current_time(inode);
ihold(inode);
set_inode_flag(inode, FI_INC_LINK);
f2fs_lock_op(sbi);
err = f2fs_add_link(dentry, inode);
if (err)
goto out;
f2fs_unlock_op(sbi);
d_instantiate(dentry, inode);
if (IS_DIRSYNC(dir))
f2fs_sync_fs(sbi->sb, 1);
return 0;
out:
clear_inode_flag(inode, FI_INC_LINK);
iput(inode);
f2fs_unlock_op(sbi);
return err;
}
struct dentry *f2fs_get_parent(struct dentry *child)
{
struct qstr dotdot = QSTR_INIT("..", 2);
struct page *page;
unsigned long ino = f2fs_inode_by_name(d_inode(child), &dotdot, &page);
if (!ino) {
if (IS_ERR(page))
return ERR_CAST(page);
return ERR_PTR(-ENOENT);
}
return d_obtain_alias(f2fs_iget(child->d_sb, ino));
}
static int __recover_dot_dentries(struct inode *dir, nid_t pino)
{
struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
struct qstr dot = QSTR_INIT(".", 1);
struct qstr dotdot = QSTR_INIT("..", 2);
struct f2fs_dir_entry *de;
struct page *page;
int err = 0;
if (f2fs_readonly(sbi->sb)) {
f2fs_msg(sbi->sb, KERN_INFO,
"skip recovering inline_dots inode (ino:%lu, pino:%u) "
"in readonly mountpoint", dir->i_ino, pino);
return 0;
}
err = dquot_initialize(dir);
if (err)
return err;
f2fs_balance_fs(sbi, true);
f2fs_lock_op(sbi);
de = f2fs_find_entry(dir, &dot, &page);
if (de) {
f2fs_dentry_kunmap(dir, page);
f2fs_put_page(page, 0);
} else if (IS_ERR(page)) {
err = PTR_ERR(page);
goto out;
} else {
err = __f2fs_add_link(dir, &dot, NULL, dir->i_ino, S_IFDIR);
if (err)
goto out;
}
de = f2fs_find_entry(dir, &dotdot, &page);
if (de) {
f2fs_dentry_kunmap(dir, page);
f2fs_put_page(page, 0);
} else if (IS_ERR(page)) {
err = PTR_ERR(page);
} else {
err = __f2fs_add_link(dir, &dotdot, NULL, pino, S_IFDIR);
}
out:
if (!err)
clear_inode_flag(dir, FI_INLINE_DOTS);
f2fs_unlock_op(sbi);
return err;
}
static struct dentry *f2fs_lookup(struct inode *dir, struct dentry *dentry,
unsigned int flags)
{
struct inode *inode = NULL;
struct f2fs_dir_entry *de;
struct page *page;
nid_t ino;
int err = 0;
unsigned int root_ino = F2FS_ROOT_INO(F2FS_I_SB(dir));
if (f2fs_encrypted_inode(dir)) {
int res = fscrypt_get_encryption_info(dir);
/*
* DCACHE_ENCRYPTED_WITH_KEY is set if the dentry is
* created while the directory was encrypted and we
* don't have access to the key.
*/
if (fscrypt_has_encryption_key(dir))
fscrypt_set_encrypted_dentry(dentry);
fscrypt_set_d_op(dentry);
if (res && res != -ENOKEY)
return ERR_PTR(res);
}
if (dentry->d_name.len > F2FS_NAME_LEN)
return ERR_PTR(-ENAMETOOLONG);
de = f2fs_find_entry(dir, &dentry->d_name, &page);
if (!de) {
if (IS_ERR(page))
return (struct dentry *)page;
return d_splice_alias(inode, dentry);
}
ino = le32_to_cpu(de->ino);
f2fs_dentry_kunmap(dir, page);
f2fs_put_page(page, 0);
inode = f2fs_iget(dir->i_sb, ino);
if (IS_ERR(inode))
return ERR_CAST(inode);
if ((dir->i_ino == root_ino) && f2fs_has_inline_dots(dir)) {
err = __recover_dot_dentries(dir, root_ino);
if (err)
goto err_out;
}
if (f2fs_has_inline_dots(inode)) {
err = __recover_dot_dentries(inode, dir->i_ino);
if (err)
goto err_out;
}
if (f2fs_encrypted_inode(dir) &&
(S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) &&
!fscrypt_has_permitted_context(dir, inode)) {
f2fs_msg(inode->i_sb, KERN_WARNING,
"Inconsistent encryption contexts: %lu/%lu",
dir->i_ino, inode->i_ino);
err = -EPERM;
goto err_out;
}
return d_splice_alias(inode, dentry);
err_out:
iput(inode);
return ERR_PTR(err);
}
static int f2fs_unlink(struct inode *dir, struct dentry *dentry)
{
struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
struct inode *inode = d_inode(dentry);
struct f2fs_dir_entry *de;
struct page *page;
int err = -ENOENT;
trace_f2fs_unlink_enter(dir, dentry);
err = dquot_initialize(dir);
if (err)
return err;
de = f2fs_find_entry(dir, &dentry->d_name, &page);
if (!de) {
if (IS_ERR(page))
err = PTR_ERR(page);
goto fail;
}
f2fs_balance_fs(sbi, true);
f2fs_lock_op(sbi);
err = acquire_orphan_inode(sbi);
if (err) {
f2fs_unlock_op(sbi);
f2fs_dentry_kunmap(dir, page);
f2fs_put_page(page, 0);
goto fail;
}
f2fs_delete_entry(de, page, dir, inode);
f2fs_unlock_op(sbi);
if (IS_DIRSYNC(dir))
f2fs_sync_fs(sbi->sb, 1);
fail:
trace_f2fs_unlink_exit(inode, err);
return err;
}
static const char *f2fs_get_link(struct dentry *dentry,
struct inode *inode,
struct delayed_call *done)
{
const char *link = page_get_link(dentry, inode, done);
if (!IS_ERR(link) && !*link) {
/* this is broken symlink case */
do_delayed_call(done);
clear_delayed_call(done);
link = ERR_PTR(-ENOENT);
}
return link;
}
static int f2fs_symlink(struct inode *dir, struct dentry *dentry,
const char *symname)
{
struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
struct inode *inode;
size_t len = strlen(symname);
struct fscrypt_str disk_link = FSTR_INIT((char *)symname, len + 1);
struct fscrypt_symlink_data *sd = NULL;
int err;
if (f2fs_encrypted_inode(dir)) {
err = fscrypt_get_encryption_info(dir);
if (err)
return err;
if (!fscrypt_has_encryption_key(dir))
return -ENOKEY;
disk_link.len = (fscrypt_fname_encrypted_size(dir, len) +
sizeof(struct fscrypt_symlink_data));
}
if (disk_link.len > dir->i_sb->s_blocksize)
return -ENAMETOOLONG;
err = dquot_initialize(dir);
if (err)
return err;
inode = f2fs_new_inode(dir, S_IFLNK | S_IRWXUGO);
if (IS_ERR(inode))
return PTR_ERR(inode);
if (f2fs_encrypted_inode(inode))
inode->i_op = &f2fs_encrypted_symlink_inode_operations;
else
inode->i_op = &f2fs_symlink_inode_operations;
inode_nohighmem(inode);
inode->i_mapping->a_ops = &f2fs_dblock_aops;
f2fs_lock_op(sbi);
err = f2fs_add_link(dentry, inode);
if (err)
goto out;
f2fs_unlock_op(sbi);
alloc_nid_done(sbi, inode->i_ino);
if (f2fs_encrypted_inode(inode)) {
struct qstr istr = QSTR_INIT(symname, len);
struct fscrypt_str ostr;
sd = kzalloc(disk_link.len, GFP_NOFS);
if (!sd) {
err = -ENOMEM;
goto err_out;
}
err = fscrypt_get_encryption_info(inode);
if (err)
goto err_out;
if (!fscrypt_has_encryption_key(inode)) {
err = -ENOKEY;
goto err_out;
}
ostr.name = sd->encrypted_path;
ostr.len = disk_link.len;
err = fscrypt_fname_usr_to_disk(inode, &istr, &ostr);
if (err)
goto err_out;
sd->len = cpu_to_le16(ostr.len);
disk_link.name = (char *)sd;
}
err = page_symlink(inode, disk_link.name, disk_link.len);
err_out:
d_instantiate_new(dentry, inode);
/*
* Let's flush symlink data in order to avoid broken symlink as much as
* possible. Nevertheless, fsyncing is the best way, but there is no
* way to get a file descriptor in order to flush that.
*
* Note that, it needs to do dir->fsync to make this recoverable.
* If the symlink path is stored into inline_data, there is no
* performance regression.
*/
if (!err) {
filemap_write_and_wait_range(inode->i_mapping, 0,
disk_link.len - 1);
if (IS_DIRSYNC(dir))
f2fs_sync_fs(sbi->sb, 1);
} else {
f2fs_unlink(dir, dentry);
}
kfree(sd);
f2fs_balance_fs(sbi, true);
return err;
out:
handle_failed_inode(inode);
return err;
}
static int f2fs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
{
struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
struct inode *inode;
int err;
err = dquot_initialize(dir);
if (err)
return err;
inode = f2fs_new_inode(dir, S_IFDIR | mode);
if (IS_ERR(inode))
return PTR_ERR(inode);
inode->i_op = &f2fs_dir_inode_operations;
inode->i_fop = &f2fs_dir_operations;
inode->i_mapping->a_ops = &f2fs_dblock_aops;
mapping_set_gfp_mask(inode->i_mapping, GFP_F2FS_HIGH_ZERO);
set_inode_flag(inode, FI_INC_LINK);
f2fs_lock_op(sbi);
err = f2fs_add_link(dentry, inode);
if (err)
goto out_fail;
f2fs_unlock_op(sbi);
alloc_nid_done(sbi, inode->i_ino);
d_instantiate_new(dentry, inode);
if (IS_DIRSYNC(dir))
f2fs_sync_fs(sbi->sb, 1);
f2fs_balance_fs(sbi, true);
return 0;
out_fail:
clear_inode_flag(inode, FI_INC_LINK);
handle_failed_inode(inode);
return err;
}
static int f2fs_rmdir(struct inode *dir, struct dentry *dentry)
{
struct inode *inode = d_inode(dentry);
if (f2fs_empty_dir(inode))
return f2fs_unlink(dir, dentry);
return -ENOTEMPTY;
}
static int f2fs_mknod(struct inode *dir, struct dentry *dentry,
umode_t mode, dev_t rdev)
{
struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
struct inode *inode;
int err = 0;
err = dquot_initialize(dir);
if (err)
return err;
inode = f2fs_new_inode(dir, mode);
if (IS_ERR(inode))
return PTR_ERR(inode);
init_special_inode(inode, inode->i_mode, rdev);
inode->i_op = &f2fs_special_inode_operations;
f2fs_lock_op(sbi);
err = f2fs_add_link(dentry, inode);
if (err)
goto out;
f2fs_unlock_op(sbi);
alloc_nid_done(sbi, inode->i_ino);
d_instantiate_new(dentry, inode);
if (IS_DIRSYNC(dir))
f2fs_sync_fs(sbi->sb, 1);
f2fs_balance_fs(sbi, true);
return 0;
out:
handle_failed_inode(inode);
return err;
}
static int __f2fs_tmpfile(struct inode *dir, struct dentry *dentry,
umode_t mode, struct inode **whiteout)
{
struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
struct inode *inode;
int err;
err = dquot_initialize(dir);
if (err)
return err;
inode = f2fs_new_inode(dir, mode);
if (IS_ERR(inode))
return PTR_ERR(inode);
if (whiteout) {
init_special_inode(inode, inode->i_mode, WHITEOUT_DEV);
inode->i_op = &f2fs_special_inode_operations;
} else {
inode->i_op = &f2fs_file_inode_operations;
inode->i_fop = &f2fs_file_operations;
inode->i_mapping->a_ops = &f2fs_dblock_aops;
}
f2fs_lock_op(sbi);
err = acquire_orphan_inode(sbi);
if (err)
goto out;
err = f2fs_do_tmpfile(inode, dir);
if (err)
goto release_out;
/*
* add this non-linked tmpfile to orphan list, in this way we could
* remove all unused data of tmpfile after abnormal power-off.
*/
add_orphan_inode(inode);
alloc_nid_done(sbi, inode->i_ino);
if (whiteout) {
f2fs_i_links_write(inode, false);
*whiteout = inode;
} else {
d_tmpfile(dentry, inode);
}
/* link_count was changed by d_tmpfile as well. */
f2fs_unlock_op(sbi);
unlock_new_inode(inode);
f2fs_balance_fs(sbi, true);
return 0;
release_out:
release_orphan_inode(sbi);
out:
handle_failed_inode(inode);
return err;
}
static int f2fs_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
{
if (f2fs_encrypted_inode(dir)) {
int err = fscrypt_get_encryption_info(dir);
if (err)
return err;
}
return __f2fs_tmpfile(dir, dentry, mode, NULL);
}
static int f2fs_create_whiteout(struct inode *dir, struct inode **whiteout)
{
return __f2fs_tmpfile(dir, NULL, S_IFCHR | WHITEOUT_MODE, whiteout);
}
static int f2fs_rename(struct inode *old_dir, struct dentry *old_dentry,
struct inode *new_dir, struct dentry *new_dentry,
unsigned int flags)
{
struct f2fs_sb_info *sbi = F2FS_I_SB(old_dir);
struct inode *old_inode = d_inode(old_dentry);
struct inode *new_inode = d_inode(new_dentry);
struct inode *whiteout = NULL;
struct page *old_dir_page;
struct page *old_page, *new_page = NULL;
struct f2fs_dir_entry *old_dir_entry = NULL;
struct f2fs_dir_entry *old_entry;
struct f2fs_dir_entry *new_entry;
bool is_old_inline = f2fs_has_inline_dentry(old_dir);
int err = -ENOENT;
if ((f2fs_encrypted_inode(old_dir) &&
!fscrypt_has_encryption_key(old_dir)) ||
(f2fs_encrypted_inode(new_dir) &&
!fscrypt_has_encryption_key(new_dir)))
return -ENOKEY;
if ((old_dir != new_dir) && f2fs_encrypted_inode(new_dir) &&
!fscrypt_has_permitted_context(new_dir, old_inode)) {
err = -EXDEV;
goto out;
}
if (is_inode_flag_set(new_dir, FI_PROJ_INHERIT) &&
(!projid_eq(F2FS_I(new_dir)->i_projid,
F2FS_I(old_dentry->d_inode)->i_projid)))
return -EXDEV;
err = dquot_initialize(old_dir);
if (err)
goto out;
err = dquot_initialize(new_dir);
if (err)
goto out;
old_entry = f2fs_find_entry(old_dir, &old_dentry->d_name, &old_page);
if (!old_entry) {
if (IS_ERR(old_page))
err = PTR_ERR(old_page);
goto out;
}
if (S_ISDIR(old_inode->i_mode)) {
old_dir_entry = f2fs_parent_dir(old_inode, &old_dir_page);
if (!old_dir_entry) {
if (IS_ERR(old_dir_page))
err = PTR_ERR(old_dir_page);
goto out_old;
}
}
if (flags & RENAME_WHITEOUT) {
err = f2fs_create_whiteout(old_dir, &whiteout);
if (err)
goto out_dir;
}
if (new_inode) {
err = -ENOTEMPTY;
if (old_dir_entry && !f2fs_empty_dir(new_inode))
goto out_whiteout;
err = -ENOENT;
new_entry = f2fs_find_entry(new_dir, &new_dentry->d_name,
&new_page);
if (!new_entry) {
if (IS_ERR(new_page))
err = PTR_ERR(new_page);
goto out_whiteout;
}
f2fs_balance_fs(sbi, true);
f2fs_lock_op(sbi);
err = acquire_orphan_inode(sbi);
if (err)
goto put_out_dir;
f2fs_set_link(new_dir, new_entry, new_page, old_inode);
new_inode->i_ctime = current_time(new_inode);
down_write(&F2FS_I(new_inode)->i_sem);
if (old_dir_entry)
f2fs_i_links_write(new_inode, false);
f2fs_i_links_write(new_inode, false);
up_write(&F2FS_I(new_inode)->i_sem);
if (!new_inode->i_nlink)
add_orphan_inode(new_inode);
else
release_orphan_inode(sbi);
} else {
f2fs_balance_fs(sbi, true);
f2fs_lock_op(sbi);
err = f2fs_add_link(new_dentry, old_inode);
if (err) {
f2fs_unlock_op(sbi);
goto out_whiteout;
}
if (old_dir_entry)
f2fs_i_links_write(new_dir, true);
/*
* old entry and new entry can locate in the same inline
* dentry in inode, when attaching new entry in inline dentry,
* it could force inline dentry conversion, after that,
* old_entry and old_page will point to wrong address, in
* order to avoid this, let's do the check and update here.
*/
if (is_old_inline && !f2fs_has_inline_dentry(old_dir)) {
f2fs_put_page(old_page, 0);
old_page = NULL;
old_entry = f2fs_find_entry(old_dir,
&old_dentry->d_name, &old_page);
if (!old_entry) {
err = -ENOENT;
if (IS_ERR(old_page))
err = PTR_ERR(old_page);
f2fs_unlock_op(sbi);
goto out_whiteout;
}
}
}
down_write(&F2FS_I(old_inode)->i_sem);
if (!old_dir_entry || whiteout)
file_lost_pino(old_inode);
else
/* adjust dir's i_pino to pass fsck check */
f2fs_i_pino_write(old_inode, new_dir->i_ino);
up_write(&F2FS_I(old_inode)->i_sem);
old_inode->i_ctime = current_time(old_inode);
f2fs_mark_inode_dirty_sync(old_inode, false);
f2fs_delete_entry(old_entry, old_page, old_dir, NULL);
if (whiteout) {
whiteout->i_state |= I_LINKABLE;
set_inode_flag(whiteout, FI_INC_LINK);
err = f2fs_add_link(old_dentry, whiteout);
if (err)
goto put_out_dir;
whiteout->i_state &= ~I_LINKABLE;
iput(whiteout);
}
if (old_dir_entry) {
if (old_dir != new_dir && !whiteout) {
f2fs_set_link(old_inode, old_dir_entry,
old_dir_page, new_dir);
} else {
f2fs_dentry_kunmap(old_inode, old_dir_page);
f2fs_put_page(old_dir_page, 0);
}
f2fs_i_links_write(old_dir, false);
}
f2fs_unlock_op(sbi);
if (IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir))
f2fs_sync_fs(sbi->sb, 1);
return 0;
put_out_dir:
f2fs_unlock_op(sbi);
if (new_page) {
f2fs_dentry_kunmap(new_dir, new_page);
f2fs_put_page(new_page, 0);
}
out_whiteout:
if (whiteout)
iput(whiteout);
out_dir:
if (old_dir_entry) {
f2fs_dentry_kunmap(old_inode, old_dir_page);
f2fs_put_page(old_dir_page, 0);
}
out_old:
f2fs_dentry_kunmap(old_dir, old_page);
f2fs_put_page(old_page, 0);
out:
return err;
}
static int f2fs_cross_rename(struct inode *old_dir, struct dentry *old_dentry,
struct inode *new_dir, struct dentry *new_dentry)
{
struct f2fs_sb_info *sbi = F2FS_I_SB(old_dir);
struct inode *old_inode = d_inode(old_dentry);
struct inode *new_inode = d_inode(new_dentry);
struct page *old_dir_page, *new_dir_page;
struct page *old_page, *new_page;
struct f2fs_dir_entry *old_dir_entry = NULL, *new_dir_entry = NULL;
struct f2fs_dir_entry *old_entry, *new_entry;
int old_nlink = 0, new_nlink = 0;
int err = -ENOENT;
if ((f2fs_encrypted_inode(old_dir) &&
!fscrypt_has_encryption_key(old_dir)) ||
(f2fs_encrypted_inode(new_dir) &&
!fscrypt_has_encryption_key(new_dir)))
return -ENOKEY;
if ((f2fs_encrypted_inode(old_dir) || f2fs_encrypted_inode(new_dir)) &&
(old_dir != new_dir) &&
(!fscrypt_has_permitted_context(new_dir, old_inode) ||
!fscrypt_has_permitted_context(old_dir, new_inode)))
return -EXDEV;
if ((is_inode_flag_set(new_dir, FI_PROJ_INHERIT) &&
!projid_eq(F2FS_I(new_dir)->i_projid,
F2FS_I(old_dentry->d_inode)->i_projid)) ||
(is_inode_flag_set(new_dir, FI_PROJ_INHERIT) &&
!projid_eq(F2FS_I(old_dir)->i_projid,
F2FS_I(new_dentry->d_inode)->i_projid)))
return -EXDEV;
err = dquot_initialize(old_dir);
if (err)
goto out;
err = dquot_initialize(new_dir);
if (err)
goto out;
old_entry = f2fs_find_entry(old_dir, &old_dentry->d_name, &old_page);
if (!old_entry) {
if (IS_ERR(old_page))
err = PTR_ERR(old_page);
goto out;
}
new_entry = f2fs_find_entry(new_dir, &new_dentry->d_name, &new_page);
if (!new_entry) {
if (IS_ERR(new_page))
err = PTR_ERR(new_page);
goto out_old;
}
/* prepare for updating ".." directory entry info later */
if (old_dir != new_dir) {
if (S_ISDIR(old_inode->i_mode)) {
old_dir_entry = f2fs_parent_dir(old_inode,
&old_dir_page);
if (!old_dir_entry) {
if (IS_ERR(old_dir_page))
err = PTR_ERR(old_dir_page);
goto out_new;
}
}
if (S_ISDIR(new_inode->i_mode)) {
new_dir_entry = f2fs_parent_dir(new_inode,
&new_dir_page);
if (!new_dir_entry) {
if (IS_ERR(new_dir_page))
err = PTR_ERR(new_dir_page);
goto out_old_dir;
}
}
}
/*
* If cross rename between file and directory those are not
* in the same directory, we will inc nlink of file's parent
* later, so we should check upper boundary of its nlink.
*/
if ((!old_dir_entry || !new_dir_entry) &&
old_dir_entry != new_dir_entry) {
old_nlink = old_dir_entry ? -1 : 1;
new_nlink = -old_nlink;
err = -EMLINK;
if ((old_nlink > 0 && old_dir->i_nlink >= F2FS_LINK_MAX) ||
(new_nlink > 0 && new_dir->i_nlink >= F2FS_LINK_MAX))
goto out_new_dir;
}
f2fs_balance_fs(sbi, true);
f2fs_lock_op(sbi);
/* update ".." directory entry info of old dentry */
if (old_dir_entry)
f2fs_set_link(old_inode, old_dir_entry, old_dir_page, new_dir);
/* update ".." directory entry info of new dentry */
if (new_dir_entry)
f2fs_set_link(new_inode, new_dir_entry, new_dir_page, old_dir);
/* update directory entry info of old dir inode */
f2fs_set_link(old_dir, old_entry, old_page, new_inode);
down_write(&F2FS_I(old_inode)->i_sem);
if (!old_dir_entry)
file_lost_pino(old_inode);
else
/* adjust dir's i_pino to pass fsck check */
f2fs_i_pino_write(old_inode, new_dir->i_ino);
up_write(&F2FS_I(old_inode)->i_sem);
old_dir->i_ctime = current_time(old_dir);
if (old_nlink) {
down_write(&F2FS_I(old_dir)->i_sem);
f2fs_i_links_write(old_dir, old_nlink > 0);
up_write(&F2FS_I(old_dir)->i_sem);
}
f2fs_mark_inode_dirty_sync(old_dir, false);
/* update directory entry info of new dir inode */
f2fs_set_link(new_dir, new_entry, new_page, old_inode);
down_write(&F2FS_I(new_inode)->i_sem);
if (!new_dir_entry)
file_lost_pino(new_inode);
else
/* adjust dir's i_pino to pass fsck check */
f2fs_i_pino_write(new_inode, old_dir->i_ino);
up_write(&F2FS_I(new_inode)->i_sem);
new_dir->i_ctime = current_time(new_dir);
if (new_nlink) {
down_write(&F2FS_I(new_dir)->i_sem);
f2fs_i_links_write(new_dir, new_nlink > 0);
up_write(&F2FS_I(new_dir)->i_sem);
}
f2fs_mark_inode_dirty_sync(new_dir, false);
f2fs_unlock_op(sbi);
if (IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir))
f2fs_sync_fs(sbi->sb, 1);
return 0;
out_new_dir:
if (new_dir_entry) {
f2fs_dentry_kunmap(new_inode, new_dir_page);
f2fs_put_page(new_dir_page, 0);
}
out_old_dir:
if (old_dir_entry) {
f2fs_dentry_kunmap(old_inode, old_dir_page);
f2fs_put_page(old_dir_page, 0);
}
out_new:
f2fs_dentry_kunmap(new_dir, new_page);
f2fs_put_page(new_page, 0);
out_old:
f2fs_dentry_kunmap(old_dir, old_page);
f2fs_put_page(old_page, 0);
out:
return err;
}
static int f2fs_rename2(struct inode *old_dir, struct dentry *old_dentry,
struct inode *new_dir, struct dentry *new_dentry,
unsigned int flags)
{
if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT))
return -EINVAL;
if (flags & RENAME_EXCHANGE) {
return f2fs_cross_rename(old_dir, old_dentry,
new_dir, new_dentry);
}
/*
* VFS has already handled the new dentry existence case,
* here, we just deal with "RENAME_NOREPLACE" as regular rename.
*/
return f2fs_rename(old_dir, old_dentry, new_dir, new_dentry, flags);
}
static const char *f2fs_encrypted_get_link(struct dentry *dentry,
struct inode *inode,
struct delayed_call *done)
{
struct page *cpage = NULL;
char *caddr, *paddr = NULL;
struct fscrypt_str cstr = FSTR_INIT(NULL, 0);
struct fscrypt_str pstr = FSTR_INIT(NULL, 0);
struct fscrypt_symlink_data *sd;
u32 max_size = inode->i_sb->s_blocksize;
int res;
if (!dentry)
return ERR_PTR(-ECHILD);
res = fscrypt_get_encryption_info(inode);
if (res)
return ERR_PTR(res);
cpage = read_mapping_page(inode->i_mapping, 0, NULL);
if (IS_ERR(cpage))
return ERR_CAST(cpage);
caddr = page_address(cpage);
/* Symlink is encrypted */
sd = (struct fscrypt_symlink_data *)caddr;
cstr.name = sd->encrypted_path;
cstr.len = le16_to_cpu(sd->len);
/* this is broken symlink case */
if (unlikely(cstr.len == 0)) {
res = -ENOENT;
goto errout;
}
if ((cstr.len + sizeof(struct fscrypt_symlink_data) - 1) > max_size) {
/* Symlink data on the disk is corrupted */
res = -EIO;
goto errout;
}
res = fscrypt_fname_alloc_buffer(inode, cstr.len, &pstr);
if (res)
goto errout;
res = fscrypt_fname_disk_to_usr(inode, 0, 0, &cstr, &pstr);
if (res)
goto errout;
/* this is broken symlink case */
if (unlikely(pstr.name[0] == 0)) {
res = -ENOENT;
goto errout;
}
paddr = pstr.name;
/* Null-terminate the name */
paddr[pstr.len] = '\0';
put_page(cpage);
set_delayed_call(done, kfree_link, paddr);
return paddr;
errout:
fscrypt_fname_free_buffer(&pstr);
put_page(cpage);
return ERR_PTR(res);
}
const struct inode_operations f2fs_encrypted_symlink_inode_operations = {
.get_link = f2fs_encrypted_get_link,
.getattr = f2fs_getattr,
.setattr = f2fs_setattr,
#ifdef CONFIG_F2FS_FS_XATTR
.listxattr = f2fs_listxattr,
#endif
};
const struct inode_operations f2fs_dir_inode_operations = {
.create = f2fs_create,
.lookup = f2fs_lookup,
.link = f2fs_link,
.unlink = f2fs_unlink,
.symlink = f2fs_symlink,
.mkdir = f2fs_mkdir,
.rmdir = f2fs_rmdir,
.mknod = f2fs_mknod,
.rename = f2fs_rename2,
.tmpfile = f2fs_tmpfile,
.getattr = f2fs_getattr,
.setattr = f2fs_setattr,
.get_acl = f2fs_get_acl,
.set_acl = f2fs_set_acl,
#ifdef CONFIG_F2FS_FS_XATTR
.listxattr = f2fs_listxattr,
#endif
};
const struct inode_operations f2fs_symlink_inode_operations = {
.get_link = f2fs_get_link,
.getattr = f2fs_getattr,
.setattr = f2fs_setattr,
#ifdef CONFIG_F2FS_FS_XATTR
.listxattr = f2fs_listxattr,
#endif
};
const struct inode_operations f2fs_special_inode_operations = {
.getattr = f2fs_getattr,
.setattr = f2fs_setattr,
.get_acl = f2fs_get_acl,
.set_acl = f2fs_set_acl,
#ifdef CONFIG_F2FS_FS_XATTR
.listxattr = f2fs_listxattr,
#endif
};