linux-stable/fs/hpfs/inode.c
Christian Brauner c1632a0f11
fs: port ->setattr() to pass mnt_idmap
Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2023-01-19 09:24:02 +01:00

318 lines
8.9 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* linux/fs/hpfs/inode.c
*
* Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
*
* inode VFS functions
*/
#include <linux/slab.h>
#include <linux/user_namespace.h>
#include "hpfs_fn.h"
void hpfs_init_inode(struct inode *i)
{
struct super_block *sb = i->i_sb;
struct hpfs_inode_info *hpfs_inode = hpfs_i(i);
i->i_uid = hpfs_sb(sb)->sb_uid;
i->i_gid = hpfs_sb(sb)->sb_gid;
i->i_mode = hpfs_sb(sb)->sb_mode;
i->i_size = -1;
i->i_blocks = -1;
hpfs_inode->i_dno = 0;
hpfs_inode->i_n_secs = 0;
hpfs_inode->i_file_sec = 0;
hpfs_inode->i_disk_sec = 0;
hpfs_inode->i_dpos = 0;
hpfs_inode->i_dsubdno = 0;
hpfs_inode->i_ea_mode = 0;
hpfs_inode->i_ea_uid = 0;
hpfs_inode->i_ea_gid = 0;
hpfs_inode->i_ea_size = 0;
hpfs_inode->i_rddir_off = NULL;
hpfs_inode->i_dirty = 0;
i->i_ctime.tv_sec = i->i_ctime.tv_nsec = 0;
i->i_mtime.tv_sec = i->i_mtime.tv_nsec = 0;
i->i_atime.tv_sec = i->i_atime.tv_nsec = 0;
}
void hpfs_read_inode(struct inode *i)
{
struct buffer_head *bh;
struct fnode *fnode;
struct super_block *sb = i->i_sb;
struct hpfs_inode_info *hpfs_inode = hpfs_i(i);
void *ea;
int ea_size;
if (!(fnode = hpfs_map_fnode(sb, i->i_ino, &bh))) {
/*i->i_mode |= S_IFREG;
i->i_mode &= ~0111;
i->i_op = &hpfs_file_iops;
i->i_fop = &hpfs_file_ops;
clear_nlink(i);*/
make_bad_inode(i);
return;
}
if (hpfs_sb(i->i_sb)->sb_eas) {
if ((ea = hpfs_get_ea(i->i_sb, fnode, "UID", &ea_size))) {
if (ea_size == 2) {
i_uid_write(i, le16_to_cpu(*(__le16*)ea));
hpfs_inode->i_ea_uid = 1;
}
kfree(ea);
}
if ((ea = hpfs_get_ea(i->i_sb, fnode, "GID", &ea_size))) {
if (ea_size == 2) {
i_gid_write(i, le16_to_cpu(*(__le16*)ea));
hpfs_inode->i_ea_gid = 1;
}
kfree(ea);
}
if ((ea = hpfs_get_ea(i->i_sb, fnode, "SYMLINK", &ea_size))) {
kfree(ea);
i->i_mode = S_IFLNK | 0777;
i->i_op = &page_symlink_inode_operations;
inode_nohighmem(i);
i->i_data.a_ops = &hpfs_symlink_aops;
set_nlink(i, 1);
i->i_size = ea_size;
i->i_blocks = 1;
brelse(bh);
return;
}
if ((ea = hpfs_get_ea(i->i_sb, fnode, "MODE", &ea_size))) {
int rdev = 0;
umode_t mode = hpfs_sb(sb)->sb_mode;
if (ea_size == 2) {
mode = le16_to_cpu(*(__le16*)ea);
hpfs_inode->i_ea_mode = 1;
}
kfree(ea);
i->i_mode = mode;
if (S_ISBLK(mode) || S_ISCHR(mode)) {
if ((ea = hpfs_get_ea(i->i_sb, fnode, "DEV", &ea_size))) {
if (ea_size == 4)
rdev = le32_to_cpu(*(__le32*)ea);
kfree(ea);
}
}
if (S_ISBLK(mode) || S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
brelse(bh);
set_nlink(i, 1);
i->i_size = 0;
i->i_blocks = 1;
init_special_inode(i, mode,
new_decode_dev(rdev));
return;
}
}
}
if (fnode_is_dir(fnode)) {
int n_dnodes, n_subdirs;
i->i_mode |= S_IFDIR;
i->i_op = &hpfs_dir_iops;
i->i_fop = &hpfs_dir_ops;
hpfs_inode->i_parent_dir = le32_to_cpu(fnode->up);
hpfs_inode->i_dno = le32_to_cpu(fnode->u.external[0].disk_secno);
if (hpfs_sb(sb)->sb_chk >= 2) {
struct buffer_head *bh0;
if (hpfs_map_fnode(sb, hpfs_inode->i_parent_dir, &bh0)) brelse(bh0);
}
n_dnodes = 0; n_subdirs = 0;
hpfs_count_dnodes(i->i_sb, hpfs_inode->i_dno, &n_dnodes, &n_subdirs, NULL);
i->i_blocks = 4 * n_dnodes;
i->i_size = 2048 * n_dnodes;
set_nlink(i, 2 + n_subdirs);
} else {
i->i_mode |= S_IFREG;
if (!hpfs_inode->i_ea_mode) i->i_mode &= ~0111;
i->i_op = &hpfs_file_iops;
i->i_fop = &hpfs_file_ops;
set_nlink(i, 1);
i->i_size = le32_to_cpu(fnode->file_size);
i->i_blocks = ((i->i_size + 511) >> 9) + 1;
i->i_data.a_ops = &hpfs_aops;
hpfs_i(i)->mmu_private = i->i_size;
}
brelse(bh);
}
static void hpfs_write_inode_ea(struct inode *i, struct fnode *fnode)
{
struct hpfs_inode_info *hpfs_inode = hpfs_i(i);
/*if (le32_to_cpu(fnode->acl_size_l) || le16_to_cpu(fnode->acl_size_s)) {
Some unknown structures like ACL may be in fnode,
we'd better not overwrite them
hpfs_error(i->i_sb, "fnode %08x has some unknown HPFS386 structures", i->i_ino);
} else*/ if (hpfs_sb(i->i_sb)->sb_eas >= 2) {
__le32 ea;
if (!uid_eq(i->i_uid, hpfs_sb(i->i_sb)->sb_uid) || hpfs_inode->i_ea_uid) {
ea = cpu_to_le32(i_uid_read(i));
hpfs_set_ea(i, fnode, "UID", (char*)&ea, 2);
hpfs_inode->i_ea_uid = 1;
}
if (!gid_eq(i->i_gid, hpfs_sb(i->i_sb)->sb_gid) || hpfs_inode->i_ea_gid) {
ea = cpu_to_le32(i_gid_read(i));
hpfs_set_ea(i, fnode, "GID", (char *)&ea, 2);
hpfs_inode->i_ea_gid = 1;
}
if (!S_ISLNK(i->i_mode))
if ((i->i_mode != ((hpfs_sb(i->i_sb)->sb_mode & ~(S_ISDIR(i->i_mode) ? 0 : 0111))
| (S_ISDIR(i->i_mode) ? S_IFDIR : S_IFREG))
&& i->i_mode != ((hpfs_sb(i->i_sb)->sb_mode & ~(S_ISDIR(i->i_mode) ? 0222 : 0333))
| (S_ISDIR(i->i_mode) ? S_IFDIR : S_IFREG))) || hpfs_inode->i_ea_mode) {
ea = cpu_to_le32(i->i_mode);
/* sick, but legal */
hpfs_set_ea(i, fnode, "MODE", (char *)&ea, 2);
hpfs_inode->i_ea_mode = 1;
}
if (S_ISBLK(i->i_mode) || S_ISCHR(i->i_mode)) {
ea = cpu_to_le32(new_encode_dev(i->i_rdev));
hpfs_set_ea(i, fnode, "DEV", (char *)&ea, 4);
}
}
}
void hpfs_write_inode(struct inode *i)
{
struct hpfs_inode_info *hpfs_inode = hpfs_i(i);
struct inode *parent;
if (i->i_ino == hpfs_sb(i->i_sb)->sb_root) return;
if (hpfs_inode->i_rddir_off && !atomic_read(&i->i_count)) {
if (*hpfs_inode->i_rddir_off)
pr_err("write_inode: some position still there\n");
kfree(hpfs_inode->i_rddir_off);
hpfs_inode->i_rddir_off = NULL;
}
if (!i->i_nlink) {
return;
}
parent = iget_locked(i->i_sb, hpfs_inode->i_parent_dir);
if (parent) {
hpfs_inode->i_dirty = 0;
if (parent->i_state & I_NEW) {
hpfs_init_inode(parent);
hpfs_read_inode(parent);
unlock_new_inode(parent);
}
hpfs_write_inode_nolock(i);
iput(parent);
}
}
void hpfs_write_inode_nolock(struct inode *i)
{
struct hpfs_inode_info *hpfs_inode = hpfs_i(i);
struct buffer_head *bh;
struct fnode *fnode;
struct quad_buffer_head qbh;
struct hpfs_dirent *de;
if (i->i_ino == hpfs_sb(i->i_sb)->sb_root) return;
if (!(fnode = hpfs_map_fnode(i->i_sb, i->i_ino, &bh))) return;
if (i->i_ino != hpfs_sb(i->i_sb)->sb_root && i->i_nlink) {
if (!(de = map_fnode_dirent(i->i_sb, i->i_ino, fnode, &qbh))) {
brelse(bh);
return;
}
} else de = NULL;
if (S_ISREG(i->i_mode)) {
fnode->file_size = cpu_to_le32(i->i_size);
if (de) de->file_size = cpu_to_le32(i->i_size);
} else if (S_ISDIR(i->i_mode)) {
fnode->file_size = cpu_to_le32(0);
if (de) de->file_size = cpu_to_le32(0);
}
hpfs_write_inode_ea(i, fnode);
if (de) {
de->write_date = cpu_to_le32(gmt_to_local(i->i_sb, i->i_mtime.tv_sec));
de->read_date = cpu_to_le32(gmt_to_local(i->i_sb, i->i_atime.tv_sec));
de->creation_date = cpu_to_le32(gmt_to_local(i->i_sb, i->i_ctime.tv_sec));
de->read_only = !(i->i_mode & 0222);
de->ea_size = cpu_to_le32(hpfs_inode->i_ea_size);
hpfs_mark_4buffers_dirty(&qbh);
hpfs_brelse4(&qbh);
}
if (S_ISDIR(i->i_mode)) {
if ((de = map_dirent(i, hpfs_inode->i_dno, "\001\001", 2, NULL, &qbh))) {
de->write_date = cpu_to_le32(gmt_to_local(i->i_sb, i->i_mtime.tv_sec));
de->read_date = cpu_to_le32(gmt_to_local(i->i_sb, i->i_atime.tv_sec));
de->creation_date = cpu_to_le32(gmt_to_local(i->i_sb, i->i_ctime.tv_sec));
de->read_only = !(i->i_mode & 0222);
de->ea_size = cpu_to_le32(/*hpfs_inode->i_ea_size*/0);
de->file_size = cpu_to_le32(0);
hpfs_mark_4buffers_dirty(&qbh);
hpfs_brelse4(&qbh);
} else
hpfs_error(i->i_sb,
"directory %08lx doesn't have '.' entry",
(unsigned long)i->i_ino);
}
mark_buffer_dirty(bh);
brelse(bh);
}
int hpfs_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
struct iattr *attr)
{
struct inode *inode = d_inode(dentry);
int error = -EINVAL;
hpfs_lock(inode->i_sb);
if (inode->i_ino == hpfs_sb(inode->i_sb)->sb_root)
goto out_unlock;
if ((attr->ia_valid & ATTR_UID) &&
from_kuid(&init_user_ns, attr->ia_uid) >= 0x10000)
goto out_unlock;
if ((attr->ia_valid & ATTR_GID) &&
from_kgid(&init_user_ns, attr->ia_gid) >= 0x10000)
goto out_unlock;
if ((attr->ia_valid & ATTR_SIZE) && attr->ia_size > inode->i_size)
goto out_unlock;
error = setattr_prepare(&nop_mnt_idmap, dentry, attr);
if (error)
goto out_unlock;
if ((attr->ia_valid & ATTR_SIZE) &&
attr->ia_size != i_size_read(inode)) {
error = inode_newsize_ok(inode, attr->ia_size);
if (error)
goto out_unlock;
truncate_setsize(inode, attr->ia_size);
hpfs_truncate(inode);
}
setattr_copy(&nop_mnt_idmap, inode, attr);
hpfs_write_inode(inode);
out_unlock:
hpfs_unlock(inode->i_sb);
return error;
}
void hpfs_write_if_changed(struct inode *inode)
{
struct hpfs_inode_info *hpfs_inode = hpfs_i(inode);
if (hpfs_inode->i_dirty)
hpfs_write_inode(inode);
}
void hpfs_evict_inode(struct inode *inode)
{
truncate_inode_pages_final(&inode->i_data);
clear_inode(inode);
if (!inode->i_nlink) {
hpfs_lock(inode->i_sb);
hpfs_remove_fnode(inode->i_sb, inode->i_ino);
hpfs_unlock(inode->i_sb);
}
}