[PATCH v3 17/18] ubifs: convert to fileattr

From: Miklos Szeredi
Date: Thu Mar 25 2021 - 15:39:17 EST


Use the fileattr API to let the VFS handle locking, permission checking and
conversion.

Signed-off-by: Miklos Szeredi <mszeredi@xxxxxxxxxx>
Cc: Richard Weinberger <richard@xxxxxx>
---
fs/ubifs/dir.c | 2 ++
fs/ubifs/file.c | 2 ++
fs/ubifs/ioctl.c | 74 ++++++++++++++++++++----------------------------
fs/ubifs/ubifs.h | 3 ++
4 files changed, 38 insertions(+), 43 deletions(-)

diff --git a/fs/ubifs/dir.c b/fs/ubifs/dir.c
index d9d8d7794eff..5bd8482e660a 100644
--- a/fs/ubifs/dir.c
+++ b/fs/ubifs/dir.c
@@ -1637,6 +1637,8 @@ const struct inode_operations ubifs_dir_inode_operations = {
.listxattr = ubifs_listxattr,
.update_time = ubifs_update_time,
.tmpfile = ubifs_tmpfile,
+ .fileattr_get = ubifs_fileattr_get,
+ .fileattr_set = ubifs_fileattr_set,
};

const struct file_operations ubifs_dir_operations = {
diff --git a/fs/ubifs/file.c b/fs/ubifs/file.c
index 0e4b4be3aa26..2e4e1d159969 100644
--- a/fs/ubifs/file.c
+++ b/fs/ubifs/file.c
@@ -1648,6 +1648,8 @@ const struct inode_operations ubifs_file_inode_operations = {
.getattr = ubifs_getattr,
.listxattr = ubifs_listxattr,
.update_time = ubifs_update_time,
+ .fileattr_get = ubifs_fileattr_get,
+ .fileattr_set = ubifs_fileattr_set,
};

const struct inode_operations ubifs_symlink_inode_operations = {
diff --git a/fs/ubifs/ioctl.c b/fs/ubifs/ioctl.c
index 2326d5122beb..073855b56c82 100644
--- a/fs/ubifs/ioctl.c
+++ b/fs/ubifs/ioctl.c
@@ -14,6 +14,7 @@

#include <linux/compat.h>
#include <linux/mount.h>
+#include <linux/fileattr.h>
#include "ubifs.h"

/* Need to be kept consistent with checked flags in ioctl2ubifs() */
@@ -103,7 +104,7 @@ static int ubifs2ioctl(int ubifs_flags)

static int setflags(struct inode *inode, int flags)
{
- int oldflags, err, release;
+ int err, release;
struct ubifs_inode *ui = ubifs_inode(inode);
struct ubifs_info *c = inode->i_sb->s_fs_info;
struct ubifs_budget_req req = { .dirtied_ino = 1,
@@ -114,11 +115,6 @@ static int setflags(struct inode *inode, int flags)
return err;

mutex_lock(&ui->ui_mutex);
- oldflags = ubifs2ioctl(ui->flags);
- err = vfs_ioc_setflags_prepare(inode, oldflags, flags);
- if (err)
- goto out_unlock;
-
ui->flags &= ~ioctl2ubifs(UBIFS_SETTABLE_IOCTL_FLAGS);
ui->flags |= ioctl2ubifs(flags);
ubifs_set_inode_flags(inode);
@@ -132,54 +128,46 @@ static int setflags(struct inode *inode, int flags)
if (IS_SYNC(inode))
err = write_inode_now(inode, 1);
return err;
-
-out_unlock:
- mutex_unlock(&ui->ui_mutex);
- ubifs_release_budget(c, &req);
- return err;
}

-long ubifs_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+int ubifs_fileattr_get(struct dentry *dentry, struct fileattr *fa)
{
- int flags, err;
- struct inode *inode = file_inode(file);
+ struct inode *inode = d_inode(dentry);
+ int flags = ubifs2ioctl(ubifs_inode(inode)->flags);

- switch (cmd) {
- case FS_IOC_GETFLAGS:
- flags = ubifs2ioctl(ubifs_inode(inode)->flags);
+ dbg_gen("get flags: %#x, i_flags %#x", flags, inode->i_flags);
+ fileattr_fill_flags(fa, flags);

- dbg_gen("get flags: %#x, i_flags %#x", flags, inode->i_flags);
- return put_user(flags, (int __user *) arg);
+ return 0;
+}

- case FS_IOC_SETFLAGS: {
- if (IS_RDONLY(inode))
- return -EROFS;
+int ubifs_fileattr_set(struct user_namespace *mnt_userns,
+ struct dentry *dentry, struct fileattr *fa)
+{
+ struct inode *inode = d_inode(dentry);
+ int flags = fa->flags;

- if (!inode_owner_or_capable(&init_user_ns, inode))
- return -EACCES;
+ if (fileattr_has_fsx(fa))
+ return -EOPNOTSUPP;

- if (get_user(flags, (int __user *) arg))
- return -EFAULT;
+ if (flags & ~UBIFS_GETTABLE_IOCTL_FLAGS)
+ return -EOPNOTSUPP;

- if (flags & ~UBIFS_GETTABLE_IOCTL_FLAGS)
- return -EOPNOTSUPP;
- flags &= UBIFS_SETTABLE_IOCTL_FLAGS;
+ flags &= UBIFS_SETTABLE_IOCTL_FLAGS;

- if (!S_ISDIR(inode->i_mode))
- flags &= ~FS_DIRSYNC_FL;
+ if (!S_ISDIR(inode->i_mode))
+ flags &= ~FS_DIRSYNC_FL;

- /*
- * Make sure the file-system is read-write and make sure it
- * will not become read-only while we are changing the flags.
- */
- err = mnt_want_write_file(file);
- if (err)
- return err;
- dbg_gen("set flags: %#x, i_flags %#x", flags, inode->i_flags);
- err = setflags(inode, flags);
- mnt_drop_write_file(file);
- return err;
- }
+ dbg_gen("set flags: %#x, i_flags %#x", flags, inode->i_flags);
+ return setflags(inode, flags);
+}
+
+long ubifs_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ int err;
+ struct inode *inode = file_inode(file);
+
+ switch (cmd) {
case FS_IOC_SET_ENCRYPTION_POLICY: {
struct ubifs_info *c = inode->i_sb->s_fs_info;

diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h
index 7fdfdbda4b8a..b65c599a386a 100644
--- a/fs/ubifs/ubifs.h
+++ b/fs/ubifs/ubifs.h
@@ -2053,6 +2053,9 @@ int ubifs_recover_size(struct ubifs_info *c, bool in_place);
void ubifs_destroy_size_tree(struct ubifs_info *c);

/* ioctl.c */
+int ubifs_fileattr_get(struct dentry *dentry, struct fileattr *fa);
+int ubifs_fileattr_set(struct user_namespace *mnt_userns,
+ struct dentry *dentry, struct fileattr *fa);
long ubifs_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
void ubifs_set_inode_flags(struct inode *inode);
#ifdef CONFIG_COMPAT
--
2.30.2