Commit d701ea28 authored by Miklos Szeredi's avatar Miklos Szeredi
Browse files

efivars: convert to fileattr 



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

Signed-off-by: default avatarMiklos Szeredi <mszeredi@redhat.com>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
parent 9fefd5db

fs/efivarfs/file.c

+0 −77
Original line number Diff line number Diff line
@@ -106,86 +106,9 @@ static ssize_t efivarfs_file_read(struct file *file, char __user *userbuf, 
	return size;

}



static inline unsigned int efivarfs_getflags(struct inode *inode)

{

	unsigned int i_flags;

	unsigned int flags = 0;



	i_flags = inode->i_flags;

	if (i_flags & S_IMMUTABLE)

		flags |= FS_IMMUTABLE_FL;

	return flags;

}



static int

efivarfs_ioc_getxflags(struct file *file, void __user *arg)

{

	struct inode *inode = file->f_mapping->host;

	unsigned int flags = efivarfs_getflags(inode);



	if (copy_to_user(arg, &flags, sizeof(flags)))

		return -EFAULT;

	return 0;

}



static int

efivarfs_ioc_setxflags(struct file *file, void __user *arg)

{

	struct inode *inode = file->f_mapping->host;

	unsigned int flags;

	unsigned int i_flags = 0;

	unsigned int oldflags = efivarfs_getflags(inode);

	int error;



	if (!inode_owner_or_capable(&init_user_ns, inode))

		return -EACCES;



	if (copy_from_user(&flags, arg, sizeof(flags)))

		return -EFAULT;



	if (flags & ~FS_IMMUTABLE_FL)

		return -EOPNOTSUPP;



	if (flags & FS_IMMUTABLE_FL)

		i_flags |= S_IMMUTABLE;





	error = mnt_want_write_file(file);

	if (error)

		return error;



	inode_lock(inode);



	error = vfs_ioc_setflags_prepare(inode, oldflags, flags);

	if (error)

		goto out;



	inode_set_flags(inode, i_flags, S_IMMUTABLE);

out:

	inode_unlock(inode);

	mnt_drop_write_file(file);

	return error;

}



static long

efivarfs_file_ioctl(struct file *file, unsigned int cmd, unsigned long p)

{

	void __user *arg = (void __user *)p;



	switch (cmd) {

	case FS_IOC_GETFLAGS:

		return efivarfs_ioc_getxflags(file, arg);

	case FS_IOC_SETFLAGS:

		return efivarfs_ioc_setxflags(file, arg);

	}



	return -ENOTTY;

}



const struct file_operations efivarfs_file_operations = {

	.open	= simple_open,

	.read	= efivarfs_file_read,

	.write	= efivarfs_file_write,

	.llseek	= no_llseek,

	.unlocked_ioctl = efivarfs_file_ioctl,

};

fs/efivarfs/inode.c

+44 −0
Original line number Diff line number Diff line
@@ -10,9 +10,12 @@ 
#include <linux/kmemleak.h>

#include <linux/slab.h>

#include <linux/uuid.h>

#include <linux/fileattr.h>



#include "internal.h"



static const struct inode_operations efivarfs_file_inode_operations;



struct inode *efivarfs_get_inode(struct super_block *sb,

				const struct inode *dir, int mode,

				dev_t dev, bool is_removable)
@@ -26,6 +29,7 @@ struct inode *efivarfs_get_inode(struct super_block *sb, 
		inode->i_flags = is_removable ? 0 : S_IMMUTABLE;

		switch (mode & S_IFMT) {

		case S_IFREG:

			inode->i_op = &efivarfs_file_inode_operations;

			inode->i_fop = &efivarfs_file_operations;

			break;

		case S_IFDIR:
@@ -138,3 +142,43 @@ const struct inode_operations efivarfs_dir_inode_operations = { 
	.unlink = efivarfs_unlink,

	.create = efivarfs_create,

};



static int

efivarfs_fileattr_get(struct dentry *dentry, struct fileattr *fa)

{

	unsigned int i_flags;

	unsigned int flags = 0;



	i_flags = d_inode(dentry)->i_flags;

	if (i_flags & S_IMMUTABLE)

		flags |= FS_IMMUTABLE_FL;



	fileattr_fill_flags(fa, flags);



	return 0;

}



static int

efivarfs_fileattr_set(struct user_namespace *mnt_userns,

		      struct dentry *dentry, struct fileattr *fa)

{

	unsigned int i_flags = 0;



	if (fileattr_has_fsx(fa))

		return -EOPNOTSUPP;



	if (fa->flags & ~FS_IMMUTABLE_FL)

		return -EOPNOTSUPP;



	if (fa->flags & FS_IMMUTABLE_FL)

		i_flags |= S_IMMUTABLE;



	inode_set_flags(d_inode(dentry), i_flags, S_IMMUTABLE);



	return 0;

}



static const struct inode_operations efivarfs_file_inode_operations = {

	.fileattr_get = efivarfs_fileattr_get,

	.fileattr_set = efivarfs_fileattr_set,

};