Exemplo n.º 1
0
static int
ecryptfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
{
	int rc;
	struct dentry *lower_dentry;
	struct dentry *lower_dir_dentry;

	lower_dentry = ecryptfs_dentry_to_lower(dentry);
	lower_dir_dentry = lock_parent(lower_dentry);
	rc = vfs_mknod(lower_dir_dentry->d_inode, lower_dentry, mode, dev);
	if (rc || !lower_dentry->d_inode)
		goto out;
	rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0);
	if (rc)
		goto out;
	fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
	fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
out:
	unlock_dir(lower_dir_dentry);
	if (!dentry->d_inode)
		d_drop(dentry);
	return rc;
}
Exemplo n.º 2
0
static int
ecryptfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
{
	int rc;
	struct dentry *lower_dentry;
	struct dentry *lower_dir_dentry;

	lower_dentry = ecryptfs_dentry_to_lower(dentry);
	lower_dir_dentry = lock_parent(lower_dentry);
	rc = vfs_mknod(d_inode(lower_dir_dentry), lower_dentry, mode, dev);
	if (rc || d_really_is_negative(lower_dentry))
		goto out;
	rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb);
	if (rc)
		goto out;
	fsstack_copy_attr_times(dir, d_inode(lower_dir_dentry));
	fsstack_copy_inode_size(dir, d_inode(lower_dir_dentry));
out:
	unlock_dir(lower_dir_dentry);
	if (d_really_is_negative(dentry))
		d_drop(dentry);
	return rc;
}
Exemplo n.º 3
0
/**
 * ecryptfs_do_create
 * @directory_inode: inode of the new file's dentry's parent in ecryptfs
 * @ecryptfs_dentry: New file's dentry in ecryptfs
 * @mode: The mode of the new file
 * @nd: nameidata of ecryptfs' parent's dentry & vfsmount
 *
 * Creates the underlying file and the eCryptfs inode which will link to
 * it. It will also update the eCryptfs directory inode to mimic the
 * stat of the lower directory inode.
 *
 * Returns zero on success; non-zero on error condition
 */
static int
ecryptfs_do_create(struct inode *directory_inode,
		   struct dentry *ecryptfs_dentry, int mode,
		   struct nameidata *nd)
{
	int rc;
	struct dentry *lower_dentry;
	struct dentry *lower_dir_dentry;

	lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry);
	lower_dir_dentry = lock_parent(lower_dentry);
	if (IS_ERR(lower_dir_dentry)) {
		ecryptfs_printk(KERN_ERR, "Error locking directory of "
				"dentry\n");
		rc = PTR_ERR(lower_dir_dentry);
		goto out;
	}
	rc = ecryptfs_create_underlying_file(lower_dir_dentry->d_inode,
					     ecryptfs_dentry, mode, nd);
	if (rc) {
		printk(KERN_ERR "%s: Failure to create dentry in lower fs; "
		       "rc = [%d]\n", __func__, rc);
		goto out_lock;
	}
	rc = ecryptfs_interpose(lower_dentry, ecryptfs_dentry,
				directory_inode->i_sb);
	if (rc) {
		ecryptfs_printk(KERN_ERR, "Failure in ecryptfs_interpose\n");
		goto out_lock;
	}
	fsstack_copy_attr_times(directory_inode, lower_dir_dentry->d_inode);
	fsstack_copy_inode_size(directory_inode, lower_dir_dentry->d_inode);
out_lock:
	unlock_dir(lower_dir_dentry);
out:
	return rc;
}
Exemplo n.º 4
0
static int ecryptfs_symlink(struct inode *dir, struct dentry *dentry,
			    const char *symname)
{
	int rc;
	struct dentry *lower_dentry;
	struct dentry *lower_dir_dentry;
	char *encoded_symname;
	int encoded_symlen;
	struct ecryptfs_crypt_stat *crypt_stat = NULL;

	lower_dentry = ecryptfs_dentry_to_lower(dentry);
	dget(lower_dentry);
	lower_dir_dentry = lock_parent(lower_dentry);
	encoded_symlen = ecryptfs_encode_filename(crypt_stat, symname,
						  strlen(symname),
						  &encoded_symname);
	if (encoded_symlen < 0) {
		rc = encoded_symlen;
		goto out_lock;
	}
	rc = vfs_symlink(lower_dir_dentry->d_inode, lower_dentry,
			 encoded_symname);
	kfree(encoded_symname);
	if (rc || !lower_dentry->d_inode)
		goto out_lock;
	rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0);
	if (rc)
		goto out_lock;
	fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
	fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
out_lock:
	unlock_dir(lower_dir_dentry);
	dput(lower_dentry);
	if (!dentry->d_inode)
		d_drop(dentry);
	return rc;
}
Exemplo n.º 5
0
/**
 * ecryptfs_do_create
 * @directory_inode: inode of the new file's dentry's parent in ecryptfs
 * @ecryptfs_dentry: New file's dentry in ecryptfs
 * @mode: The mode of the new file
 * @nd: nameidata of ecryptfs' parent's dentry & vfsmount
 *
 * Creates the underlying file and the eCryptfs inode which will link to
 * it. It will also update the eCryptfs directory inode to mimic the
 * stat of the lower directory inode.
 *
 * Returns the new eCryptfs inode on success; an ERR_PTR on error condition
 */
static struct inode *
ecryptfs_do_create(struct inode *directory_inode,
		   struct dentry *ecryptfs_dentry, umode_t mode)
{
	int rc;
	struct dentry *lower_dentry;
	struct dentry *lower_dir_dentry;
	struct inode *inode;

	lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry);
	lower_dir_dentry = lock_parent(lower_dentry);
	if (IS_ERR(lower_dir_dentry)) {
		ecryptfs_printk(KERN_ERR, "Error locking directory of "
				"dentry\n");
		inode = ERR_CAST(lower_dir_dentry);
		goto out;
	}
	rc = vfs_create(lower_dir_dentry->d_inode, lower_dentry, mode, NULL);
	if (rc) {
		printk(KERN_ERR "%s: Failure to create dentry in lower fs; "
		       "rc = [%d]\n", __func__, rc);
		inode = ERR_PTR(rc);
		goto out_lock;
	}
	inode = __ecryptfs_get_inode(lower_dentry->d_inode,
				     directory_inode->i_sb);
	if (IS_ERR(inode)) {
		vfs_unlink(lower_dir_dentry->d_inode, lower_dentry);
		goto out_lock;
	}
	fsstack_copy_attr_times(directory_inode, lower_dir_dentry->d_inode);
	fsstack_copy_inode_size(directory_inode, lower_dir_dentry->d_inode);
out_lock:
	unlock_dir(lower_dir_dentry);
out:
	return inode;
}
Exemplo n.º 6
0
static int sdcardfs_getattr(struct vfsmount *mnt, struct dentry *dentry,
		 struct kstat *stat)
{
	struct dentry *lower_dentry;
	struct inode *inode;
	struct inode *lower_inode;
	struct path lower_path;
	struct dentry *parent;
	struct sdcardfs_sb_info *sbi = SDCARDFS_SB(dentry->d_sb);

	parent = dget_parent(dentry);
	if(!check_caller_access_to_name(parent->d_inode, dentry->d_name.name,
						sbi->options.derive, 0, 0)) {
		dput(parent);
		return -EACCES;
	}
	dput(parent);

	inode = dentry->d_inode;

	sdcardfs_get_lower_path(dentry, &lower_path);
	lower_dentry = lower_path.dentry;
	lower_inode = sdcardfs_lower_inode(inode);

	fsstack_copy_attr_all(inode, lower_inode);
	fsstack_copy_inode_size(inode, lower_inode);
	/* if the dentry has been moved from other location
	 * so, on this stage, its derived permission must be 
	 * rechecked from its private field.
	 */ 
	fix_derived_permission(inode);

	generic_fillattr(inode, stat);
	sdcardfs_put_lower_path(dentry, &lower_path);
	return 0;
}
Exemplo n.º 7
0
static int ecryptfs_link(struct dentry *old_dentry, struct inode *dir,
			 struct dentry *new_dentry)
{
	struct dentry *lower_old_dentry;
	struct dentry *lower_new_dentry;
	struct dentry *lower_dir_dentry;
	u64 file_size_save;
	int rc;

	file_size_save = i_size_read(old_dentry->d_inode);
	lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry);
	lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry);
	dget(lower_old_dentry);
	dget(lower_new_dentry);
	lower_dir_dentry = lock_parent(lower_new_dentry);
	rc = vfs_link(lower_old_dentry, lower_dir_dentry->d_inode,
		      lower_new_dentry);
	if (rc || !lower_new_dentry->d_inode)
		goto out_lock;
	rc = ecryptfs_interpose(lower_new_dentry, new_dentry, dir->i_sb, 0);
	if (rc)
		goto out_lock;
	fsstack_copy_attr_times(dir, lower_new_dentry->d_inode);
	fsstack_copy_inode_size(dir, lower_new_dentry->d_inode);
	old_dentry->d_inode->i_nlink =
		ecryptfs_inode_to_lower(old_dentry->d_inode)->i_nlink;
	i_size_write(new_dentry->d_inode, file_size_save);
out_lock:
	unlock_dir(lower_dir_dentry);
	dput(lower_new_dentry);
	dput(lower_old_dentry);
	d_drop(lower_old_dentry);
	d_drop(new_dentry);
	d_drop(old_dentry);
	return rc;
}
static int wrapfs_create(struct inode *dir, struct dentry *dentry,
			 int mode, struct nameidata *nd)
{
	int err = 0;
	struct dentry *lower_dentry;
	struct dentry *lower_parent_dentry = NULL;
	struct path lower_path, saved_path;

	wrapfs_get_lower_path(dentry, &lower_path);
	lower_dentry = lower_path.dentry;
	lower_parent_dentry = lock_parent(lower_dentry);

	err = mnt_want_write(lower_path.mnt);
	if (err)
		goto out_unlock;

	pathcpy(&saved_path, &nd->path);
	pathcpy(&nd->path, &lower_path);
	err = vfs_create(lower_parent_dentry->d_inode, lower_dentry, mode, nd);
	pathcpy(&nd->path, &saved_path);
	if (err)
		goto out;

	err = wrapfs_interpose(dentry, dir->i_sb, &lower_path);
	if (err)
		goto out;
	fsstack_copy_attr_times(dir, wrapfs_lower_inode(dir));
	fsstack_copy_inode_size(dir, lower_parent_dentry->d_inode);

out:
	mnt_drop_write(lower_path.mnt);
out_unlock:
	unlock_dir(lower_parent_dentry);
	wrapfs_put_lower_path(dentry, &lower_path);
	return err;
}
Exemplo n.º 9
0
static int wrapfs_link(struct dentry *old_dentry, struct inode *dir,
		       struct dentry *new_dentry)
{
	struct dentry *lower_old_dentry;
	struct dentry *lower_new_dentry;
	struct dentry *lower_dir_dentry;
	u64 file_size_save;
	int err;
	struct path lower_old_path, lower_new_path;

	file_size_save = i_size_read(old_dentry->d_inode);
	wrapfs_get_lower_path(old_dentry, &lower_old_path);
	wrapfs_get_lower_path(new_dentry, &lower_new_path);
	lower_old_dentry = lower_old_path.dentry;
	lower_new_dentry = lower_new_path.dentry;
	lower_dir_dentry = lock_parent(lower_new_dentry);

	err = vfs_link(lower_old_dentry, lower_dir_dentry->d_inode,
		       lower_new_dentry, NULL);
	if (err || !lower_new_dentry->d_inode)
		goto out;

	err = wrapfs_interpose(new_dentry, dir->i_sb, &lower_new_path);
	if (err)
		goto out;
	fsstack_copy_attr_times(dir, lower_new_dentry->d_inode);
	fsstack_copy_inode_size(dir, lower_new_dentry->d_inode);
	set_nlink(old_dentry->d_inode,
		  wrapfs_lower_inode(old_dentry->d_inode)->i_nlink);
	i_size_write(new_dentry->d_inode, file_size_save);
out:
	unlock_dir(lower_dir_dentry);
	wrapfs_put_lower_path(old_dentry, &lower_old_path);
	wrapfs_put_lower_path(new_dentry, &lower_new_path);
	return err;
}
Exemplo n.º 10
0
static int esdfs_getattr(struct vfsmount *mnt, struct dentry *dentry,
		 struct kstat *stat)
{
	int err;
	struct path lower_path;
	struct vfsmount *lower_mount;
	struct dentry *lower_dentry;
	struct kstat lower_stat;
	struct inode *lower_inode;
	struct inode *inode = dentry->d_inode;
	const struct cred *creds =
			esdfs_override_creds(ESDFS_SB(inode->i_sb), NULL);
	if (!creds)
		return -ENOMEM;

	esdfs_get_lower_path(dentry, &lower_path);
	lower_mount = lower_path.mnt;
	lower_dentry = lower_path.dentry;

	/* We need the lower getattr to calculate stat->blocks for us. */
	err = vfs_getattr(lower_mount, lower_dentry, &lower_stat);
	if (err)
		goto out;

	lower_inode = esdfs_lower_inode(inode);
	esdfs_copy_attr(inode, lower_inode);
	fsstack_copy_inode_size(inode, lower_inode);
	generic_fillattr(inode, stat);

	stat->blocks = lower_stat.blocks;

out:
	esdfs_put_lower_path(dentry, &lower_path);
	esdfs_revert_creds(creds, NULL);
	return err;
}
Exemplo n.º 11
0
static int diaryfs_symlink(struct inode *dir, struct dentry *dentry, const char * symname) {
	int err;
	struct dentry *lower_dentry;
	struct dentry *lower_parent_dentry = NULL;
	struct path lower_path; 

	diaryfs_get_lower_path(dentry, &lower_path);
	lower_dentry = lower_path.dentry;
	lower_parent_dentry = lock_parent(lower_dentry);

	err = vfs_symlink(lower_parent_dentry->d_inode, lower_dentry, symname);
	if (err)
		goto out;
	err = diaryfs_interpose(dentry, dir->i_sb, &lower_path);
	if (err)
		goto out;
	fsstack_copy_attr_times(dir, diaryfs_lower_inode(dir));
	fsstack_copy_inode_size(dir, lower_parent_dentry->d_inode);

out:
	unlock_dir(lower_parent_dentry);
	diaryfs_put_lower_path(dentry, &lower_path);
	return err;
}
Exemplo n.º 12
0
/*
 * The locking rules in sdcardfs_rename are complex.  We could use a simpler
 * superblock-level name-space lock for renames and copy-ups.
 */
static int sdcardfs_rename(struct inode *old_dir, struct dentry *old_dentry,
			 struct inode *new_dir, struct dentry *new_dentry)
{
	int err = 0;
	struct dentry *lower_old_dentry = NULL;
	struct dentry *lower_new_dentry = NULL;
	struct dentry *lower_old_dir_dentry = NULL;
	struct dentry *lower_new_dir_dentry = NULL;
	struct dentry *trap = NULL;
	struct dentry *new_parent = NULL;
	struct path lower_old_path, lower_new_path;
	struct sdcardfs_sb_info *sbi = SDCARDFS_SB(old_dentry->d_sb);
	const struct cred *saved_cred = NULL;

	int has_rw = get_caller_has_rw_locked(sbi->pkgl_id, sbi->options.derive);
	if(!check_caller_access_to_name(old_dir, old_dentry->d_name.name,
			sbi->options.derive, 1, has_rw) ||
		!check_caller_access_to_name(new_dir, new_dentry->d_name.name,
			sbi->options.derive, 1, has_rw)) {
		err = -EACCES;
		goto out_eacces;
	}

	/* save current_cred and override it */
	OVERRIDE_CRED(SDCARDFS_SB(old_dir->i_sb), saved_cred);

	sdcardfs_get_real_lower(old_dentry, &lower_old_path);
	sdcardfs_get_lower_path(new_dentry, &lower_new_path);
	lower_old_dentry = lower_old_path.dentry;
	lower_new_dentry = lower_new_path.dentry;
	lower_old_dir_dentry = dget_parent(lower_old_dentry);
	lower_new_dir_dentry = dget_parent(lower_new_dentry);

	trap = lock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
	/* source should not be ancestor of target */
	if (trap == lower_old_dentry) {
		err = -EINVAL;
		goto out;
	}
	/* target should not be ancestor of source */
	if (trap == lower_new_dentry) {
		err = -ENOTEMPTY;
		goto out;
	}

	err = mnt_want_write(lower_old_path.mnt);
	if (err)
		goto out;
	err = mnt_want_write(lower_new_path.mnt);
	if (err)
		goto out_drop_old_write;

	err = vfs_rename(lower_old_dir_dentry->d_inode, lower_old_dentry,
			 lower_new_dir_dentry->d_inode, lower_new_dentry);
	if (err)
		goto out_err;

	/* Copy attrs from lower dir, but i_uid/i_gid */
	fsstack_copy_attr_all(new_dir, lower_new_dir_dentry->d_inode);
	fsstack_copy_inode_size(new_dir, lower_new_dir_dentry->d_inode);
	fix_derived_permission(new_dir); 
	if (new_dir != old_dir) {
		fsstack_copy_attr_all(old_dir, lower_old_dir_dentry->d_inode);
		fsstack_copy_inode_size(old_dir, lower_old_dir_dentry->d_inode);
		fix_derived_permission(old_dir);
		/* update the derived permission of the old_dentry
		 * with its new parent
		 */
		new_parent = dget_parent(new_dentry);
		if(new_parent) {
			if(old_dentry->d_inode) {
				get_derived_permission(new_parent, old_dentry);
				fix_derived_permission(old_dentry->d_inode);
			}
			dput(new_parent);
		}
	}

out_err:
	mnt_drop_write(lower_new_path.mnt);
out_drop_old_write:
	mnt_drop_write(lower_old_path.mnt);
out:
	unlock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
	dput(lower_old_dir_dentry);
	dput(lower_new_dir_dentry);
	sdcardfs_put_real_lower(old_dentry, &lower_old_path);
	sdcardfs_put_lower_path(new_dentry, &lower_new_path);
	REVERT_CRED(saved_cred);
out_eacces:
	return err;
}
Exemplo n.º 13
0
static int sdcardfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
{
	int err = 0;
	int make_nomedia_in_obb = 0;
	struct dentry *lower_dentry;
	struct dentry *lower_parent_dentry = NULL;
	struct path lower_path;
	struct sdcardfs_sb_info *sbi = SDCARDFS_SB(dentry->d_sb);
	const struct cred *saved_cred = NULL;
	struct sdcardfs_inode_info *pi = SDCARDFS_I(dir);
	char *page_buf;
	char *nomedia_dir_name;
	char *nomedia_fullpath;
	int fullpath_namelen;
	int touch_err = 0;

	char *(*d_absolute_path_new)(const struct path *, char *, int) = (void *)kallsyms_lookup_name("d_absolute_path");

	int has_rw = get_caller_has_rw_locked(sbi->pkgl_id, sbi->options.derive);
	if(!check_caller_access_to_name(dir, dentry->d_name.name, sbi->options.derive, 1, has_rw)) {
		err = -EACCES;
		goto out_eacces;
	}

	/* save current_cred and override it */
	OVERRIDE_CRED(SDCARDFS_SB(dir->i_sb), saved_cred);

	/* check disk space */
	if (!check_min_free_space(dentry, 0, 1)) {
		printk(KERN_INFO "sdcardfs: No minimum free space.\n");
		err = -ENOSPC;
		goto out_revert;
	}

	/* the lower_dentry is negative here */
	sdcardfs_get_lower_path(dentry, &lower_path);
	lower_dentry = lower_path.dentry;
	lower_parent_dentry = lock_parent(lower_dentry);

	err = mnt_want_write(lower_path.mnt);
	if (err)
		goto out_unlock;

	/* set last 16bytes of mode field to 0775 */
	mode = (mode & S_IFMT) | 00775; 
	err = vfs_mkdir(lower_parent_dentry->d_inode, lower_dentry, mode);

	if (err)
		goto out;
	
	/* if it is a local obb dentry, setup it with the base obbpath */
	if(need_graft_path(dentry)) {

		err = setup_obb_dentry(dentry, &lower_path);
		if(err) {
			/* if the sbi->obbpath is not available, the lower_path won't be 
			 * changed by setup_obb_dentry() but the lower path is saved to 
             * its orig_path. this dentry will be revalidated later.
			 * but now, the lower_path should be NULL */
			sdcardfs_put_reset_lower_path(dentry);

			/* the newly created lower path which saved to its orig_path or
			 * the lower_path is the base obbpath. 
             * therefore, an additional path_get is required */
			path_get(&lower_path);
		} else
			make_nomedia_in_obb = 1;
	}

	err = sdcardfs_interpose(dentry, dir->i_sb, &lower_path);
	if (err)
		goto out;

	fsstack_copy_attr_times(dir, sdcardfs_lower_inode(dir));
	fsstack_copy_inode_size(dir, lower_parent_dentry->d_inode);
	/* update number of links on parent directory */
	set_nlink(dir, sdcardfs_lower_inode(dir)->i_nlink);

	if ((sbi->options.derive == DERIVE_UNIFIED) && (!strcasecmp(dentry->d_name.name, "obb"))
		&& (pi->perm == PERM_ANDROID) && (pi->userid == 0))
		make_nomedia_in_obb = 1;

	/* When creating /Android/data and /Android/obb, mark them as .nomedia */
	if (make_nomedia_in_obb ||
		((pi->perm == PERM_ANDROID) && (!strcasecmp(dentry->d_name.name, "data")))) {

		page_buf = (char *)__get_free_page(GFP_KERNEL);
		if (!page_buf) {
			printk(KERN_ERR "sdcardfs: failed to allocate page buf\n");
			goto out;
		}

		nomedia_dir_name = d_absolute_path_new(&lower_path, page_buf, PAGE_SIZE);
		if (IS_ERR(nomedia_dir_name)) {
			free_page((unsigned long)page_buf);
			printk(KERN_ERR "sdcardfs: failed to get .nomedia dir name\n");
			goto out;
		}

		fullpath_namelen = page_buf + PAGE_SIZE - nomedia_dir_name - 1;
		fullpath_namelen += strlen("/.nomedia");
		nomedia_fullpath = kzalloc(fullpath_namelen + 1, GFP_KERNEL);
		if (!nomedia_fullpath) {
			free_page((unsigned long)page_buf);
			printk(KERN_ERR "sdcardfs: failed to allocate .nomedia fullpath buf\n");
			goto out;
		}

		strcpy(nomedia_fullpath, nomedia_dir_name);
		free_page((unsigned long)page_buf);
		strcat(nomedia_fullpath, "/.nomedia");
		touch_err = touch(nomedia_fullpath, 0664);
		if (touch_err) {
			printk(KERN_ERR "sdcardfs: failed to touch(%s): %d\n",
							nomedia_fullpath, touch_err);
			kfree(nomedia_fullpath);
			goto out;
		}
		kfree(nomedia_fullpath);
	}
out:
	mnt_drop_write(lower_path.mnt);
out_unlock:
	unlock_dir(lower_parent_dentry);
	sdcardfs_put_lower_path(dentry, &lower_path);
out_revert:
	REVERT_CRED(saved_cred);
out_eacces:
	return err;
}
Exemplo n.º 14
0
static struct inode *sdcardfskk_iget(struct super_block *sb,
				 struct inode *lower_inode)
{
	struct sdcardfskk_inode_info *info;
	struct inode *inode; /* the new inode to return */
	int err;

	inode = iget5_locked(sb, /* our superblock */
			     /*
			      * hashval: we use inode number, but we can
			      * also use "(unsigned long)lower_inode"
			      * instead.
			      */
			     lower_inode->i_ino, /* hashval */
			     sdcardfskk_inode_test,	/* inode comparison function */
			     sdcardfskk_inode_set, /* inode init function */
			     lower_inode); /* data passed to test+set fxns */
	if (!inode) {
		err = -EACCES;
		iput(lower_inode);
		return ERR_PTR(err);
	}
	/* if found a cached inode, then just return it */
	if (!(inode->i_state & I_NEW))
		return inode;

	/* initialize new inode */
	info = SDCARDFSKK_I(inode);

	inode->i_ino = lower_inode->i_ino;
	if (!igrab(lower_inode)) {
		err = -ESTALE;
		return ERR_PTR(err);
	}
	sdcardfskk_set_lower_inode(inode, lower_inode);

	inode->i_version++;

	/* use different set of inode ops for symlinks & directories */
	if (S_ISDIR(lower_inode->i_mode))
		inode->i_op = &sdcardfskk_dir_iops;
	else if (S_ISLNK(lower_inode->i_mode))
		inode->i_op = &sdcardfskk_symlink_iops;
	else
		inode->i_op = &sdcardfskk_main_iops;

	/* use different set of file ops for directories */
	if (S_ISDIR(lower_inode->i_mode))
		inode->i_fop = &sdcardfskk_dir_fops;
	else
		inode->i_fop = &sdcardfskk_main_fops;

	inode->i_mapping->a_ops = &sdcardfskk_aops;

	inode->i_atime.tv_sec = 0;
	inode->i_atime.tv_nsec = 0;
	inode->i_mtime.tv_sec = 0;
	inode->i_mtime.tv_nsec = 0;
	inode->i_ctime.tv_sec = 0;
	inode->i_ctime.tv_nsec = 0;

	/* properly initialize special inodes */
	if (S_ISBLK(lower_inode->i_mode) || S_ISCHR(lower_inode->i_mode) ||
	    S_ISFIFO(lower_inode->i_mode) || S_ISSOCK(lower_inode->i_mode))
		init_special_inode(inode, lower_inode->i_mode,
				   lower_inode->i_rdev);

	/* all well, copy inode attributes, don't need to hold i_mutex here */
	sdcardfskk_copy_inode_attr(inode, lower_inode);
	fsstack_copy_inode_size(inode, lower_inode);

	fix_derived_permission(inode);

	unlock_new_inode(inode);
	return inode;
}
static int u2fs_create(struct inode *dir, struct dentry *dentry,
			 int mode, struct nameidata *nd)
{
	int err = 0;
	struct dentry *lower_dentry = NULL;
	struct dentry *lower_parent_dentry = NULL;
	struct dentry *parent= NULL;
	struct dentry *ret=NULL;
	struct path lower_path, saved_path;
	const char *name;
	unsigned int namelen;
	struct dentry *right_parent_dentry = NULL;	
	struct dentry *right_lower_dentry = NULL;
	
	/* creating parent directories if destination is read-only */
	if((U2FS_D(dentry)->lower_path[LEFT].dentry) == NULL && 
		(U2FS_D(dentry)->lower_path[LEFT].mnt) == NULL){

		parent = dget_parent(dentry);
		
		right_parent_dentry = U2FS_D(parent)->lower_path[RIGHT].dentry;

		ret = create_parents(parent->d_inode, dentry,
					      dentry->d_name.name);
		if (!ret || IS_ERR(ret)) {
				err = PTR_ERR(ret);
				if (!IS_COPYUP_ERR(err))
					printk(KERN_ERR
				      	 "u2fs: create_parents for "
			     		  "u2fs_create failed"
				      	 "err=%d\n", err);
				goto out_copyup;
		}
		u2fs_postcopyup_setmnt(dentry);
		u2fs_put_reset_lower_path(dentry, RIGHT);
	}

	u2fs_get_lower_path(dentry, &lower_path, LEFT);
	lower_dentry = lower_path.dentry;
	lower_parent_dentry = lock_parent(lower_dentry);

	err = mnt_want_write(lower_path.mnt);
	if (err)
		goto out_unlock;

	pathcpy(&saved_path, &nd->path);
	pathcpy(&nd->path, &lower_path);

	err = vfs_create(lower_parent_dentry->d_inode, lower_dentry, mode, nd);
	pathcpy(&nd->path, &saved_path);
	if (err)
		goto out;

	/* looking if the file already exists in right_dir to link inode */
	if((U2FS_D(dentry)->lower_path[RIGHT].dentry) != NULL && 
		(U2FS_D(dentry)->lower_path[RIGHT].mnt) != NULL){
		
		name = dentry->d_name.name;
		namelen = dentry->d_name.len;

		right_lower_dentry = lookup_one_len(name, lower_parent_dentry,
					      namelen);

		dentry->d_inode = right_lower_dentry->d_inode;

		u2fs_set_lower_inode(dentry->d_inode, lower_dentry->d_inode, 
					LEFT);
	}
	else
		err = u2fs_interpose(dentry, dir->i_sb, &lower_path, LEFT);

	if (err)
		goto out;

	fsstack_copy_attr_times(dir, u2fs_lower_inode(dir, LEFT));
	fsstack_copy_inode_size(dir, lower_parent_dentry->d_inode);
out:
	mnt_drop_write(lower_path.mnt);
out_unlock:
	unlock_dir(lower_parent_dentry);
	u2fs_put_lower_path(dentry, &lower_path);
out_copyup:
	if(parent != NULL)
		dput(parent);
	return err;
}
Exemplo n.º 16
0
/*
 * The locking rules in amfs_rename are complex.  We could use a simpler
 * superblock-level name-space lock for renames and copy-ups.
 */
static int amfs_rename(struct inode *old_dir, struct dentry *old_dentry,
			 struct inode *new_dir, struct dentry *new_dentry)
{
	int err = 0;
	struct dentry *lower_old_dentry = NULL;
	struct dentry *lower_new_dentry = NULL;
	struct dentry *lower_old_dir_dentry = NULL;
	struct dentry *lower_new_dir_dentry = NULL;
	struct dentry *trap = NULL;
	struct path lower_old_path, lower_new_path;
	/*******Variable which will help in checking XATTR***************/
	char *value = NULL;

	if (old_dentry->d_inode->i_ino ==
				AMFS_SB(old_dentry->d_sb)->inode_no) {
		err = -EPERM;
		goto exitcode;
	}

	value = kzalloc(5, __GFP_WAIT);
	if (value == NULL) {
		err = -ENOMEM;
		goto exitcode;
	}
	if (amfs_getxattr(old_dentry, AMFS_XATTR_NAME, value, 5) > 0) {
		if (!strncmp(value, AMFS_BADFILE, 3)) {
			err = -EPERM;
			goto freevalue;
		}
	} else if (amfs_getxattr(old_dentry, AMFS_XATTR_NAME, value, 5)
			!= -ENODATA) {
		err = amfs_getxattr(old_dentry, AMFS_XATTR_NAME, value, 5);
		goto freevalue;
	}
	/****************************************************************/
	amfs_get_lower_path(old_dentry, &lower_old_path);
	amfs_get_lower_path(new_dentry, &lower_new_path);
	lower_old_dentry = lower_old_path.dentry;
	lower_new_dentry = lower_new_path.dentry;
	lower_old_dir_dentry = dget_parent(lower_old_dentry);
	lower_new_dir_dentry = dget_parent(lower_new_dentry);

	trap = lock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
	/* source should not be ancestor of target */
	if (trap == lower_old_dentry) {
		err = -EINVAL;
		goto out;
	}
	/* target should not be ancestor of source */
	if (trap == lower_new_dentry) {
		err = -ENOTEMPTY;
		goto out;
	}

	err = vfs_rename(lower_old_dir_dentry->d_inode, lower_old_dentry,
			 lower_new_dir_dentry->d_inode, lower_new_dentry,
			 NULL, 0);
	if (err)
		goto out;

	fsstack_copy_attr_all(new_dir, lower_new_dir_dentry->d_inode);
	fsstack_copy_inode_size(new_dir, lower_new_dir_dentry->d_inode);
	if (new_dir != old_dir) {
		fsstack_copy_attr_all(old_dir,
				      lower_old_dir_dentry->d_inode);
		fsstack_copy_inode_size(old_dir,
					lower_old_dir_dentry->d_inode);
	}

out:
	unlock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
	dput(lower_old_dir_dentry);
	dput(lower_new_dir_dentry);
	amfs_put_lower_path(old_dentry, &lower_old_path);
	amfs_put_lower_path(new_dentry, &lower_new_path);
freevalue:
	kfree(value);
exitcode:
	return err;
}
Exemplo n.º 17
0
/*
 * The locking rules in sdcardfs_rename are complex.  We could use a simpler
 * superblock-level name-space lock for renames and copy-ups.
 */
static int sdcardfs_rename(struct inode *old_dir, struct dentry *old_dentry,
			 struct inode *new_dir, struct dentry *new_dentry)
{
	int err = 0;
	struct dentry *lower_old_dentry = NULL;
	struct dentry *lower_new_dentry = NULL;
	struct dentry *lower_old_dir_dentry = NULL;
	struct dentry *lower_new_dir_dentry = NULL;
	struct dentry *trap = NULL;
	struct dentry *new_parent = NULL;
	struct path lower_old_path, lower_new_path;
	const struct cred *saved_cred = NULL;

	if(!check_caller_access_to_name(old_dir, old_dentry->d_name.name) ||
		!check_caller_access_to_name(new_dir, new_dentry->d_name.name)) {
		printk(KERN_INFO "%s: need to check the caller's gid in packages.list\n" 
						 "  new_dentry: %s, task:%s\n",
						 __func__, new_dentry->d_name.name, current->comm);
		err = -EACCES;
		goto out_eacces;
	}

	/* save current_cred and override it */
	OVERRIDE_CRED(SDCARDFS_SB(old_dir->i_sb), saved_cred);

	sdcardfs_get_real_lower(old_dentry, &lower_old_path);
	sdcardfs_get_lower_path(new_dentry, &lower_new_path);
	lower_old_dentry = lower_old_path.dentry;
	lower_new_dentry = lower_new_path.dentry;
	lower_old_dir_dentry = dget_parent(lower_old_dentry);
	lower_new_dir_dentry = dget_parent(lower_new_dentry);

	trap = lock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
	/* source should not be ancestor of target */
	if (trap == lower_old_dentry) {
		err = -EINVAL;
		goto out;
	}
	/* target should not be ancestor of source */
	if (trap == lower_new_dentry) {
		err = -ENOTEMPTY;
		goto out;
	}

	err = mnt_want_write(lower_old_path.mnt);
	if (err)
		goto out;
	err = mnt_want_write(lower_new_path.mnt);
	if (err)
		goto out_drop_old_write;

	err = vfs_rename(lower_old_dir_dentry->d_inode, lower_old_dentry,
			 lower_new_dir_dentry->d_inode, lower_new_dentry);
	if (err)
		goto out_err;

	/* Copy attrs from lower dir, but i_uid/i_gid */
	sdcardfs_copy_inode_attr(new_dir, lower_new_dir_dentry->d_inode);
	fsstack_copy_inode_size(new_dir, lower_new_dir_dentry->d_inode);
	fix_derived_permission(new_dir);
	if (new_dir != old_dir) {
		sdcardfs_copy_inode_attr(old_dir, lower_old_dir_dentry->d_inode);
		fsstack_copy_inode_size(old_dir, lower_old_dir_dentry->d_inode);
		fix_derived_permission(old_dir);
		/* update the derived permission of the old_dentry
		 * with its new parent
		 */
		new_parent = dget_parent(new_dentry);
		if(new_parent) {
			if(old_dentry->d_inode) {
				get_derived_permission(new_parent, old_dentry);
				fix_derived_permission(old_dentry->d_inode);
			}
			dput(new_parent);
		}
	}

out_err:
	mnt_drop_write(lower_new_path.mnt);
out_drop_old_write:
	mnt_drop_write(lower_old_path.mnt);
out:
	unlock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
	dput(lower_old_dir_dentry);
	dput(lower_new_dir_dentry);
	sdcardfs_put_real_lower(old_dentry, &lower_old_path);
	sdcardfs_put_lower_path(new_dentry, &lower_new_path);
	REVERT_CRED(saved_cred);
out_eacces:
	return err;
}
static int u2fs_link(struct dentry *old_dentry, struct inode *dir,
		       struct dentry *new_dentry)
{
	struct dentry *lower_old_dentry;
	struct dentry *lower_new_dentry;
	struct dentry *lower_dir_dentry;
	u64 file_size_save;
	int err=0;
	int idx;
	struct dentry *ret = NULL;
	struct path lower_old_path, lower_new_path;
	

	file_size_save = i_size_read(old_dentry->d_inode);

	if((U2FS_D(old_dentry)->lower_path[LEFT].dentry != NULL) &&
	(U2FS_D(old_dentry)->lower_path[LEFT].mnt != NULL)){
		u2fs_get_lower_path(old_dentry, &lower_old_path, LEFT);
		idx = LEFT;
	}
	else{
		u2fs_get_lower_path(old_dentry, &lower_old_path, RIGHT);
		idx = RIGHT;
	}

	/* creating parent directories if destination is read-only */
	if((U2FS_D(new_dentry)->lower_path[LEFT].dentry) == NULL && 
		(U2FS_D(new_dentry)->lower_path[LEFT].mnt) == NULL){

		ret = create_parents(dir, new_dentry, 
					new_dentry->d_name.name);

		if (!ret || IS_ERR(ret)) {
					err = PTR_ERR(ret);
					if (!IS_COPYUP_ERR(err))
						printk(KERN_ERR
					      	 "u2fs: create_parents for "
				     		  "u2fs_link failed"
					      	 "err=%d\n", err);
					goto out_copyup;
		}
		u2fs_postcopyup_setmnt(new_dentry);
		u2fs_put_reset_lower_path(new_dentry, RIGHT);
		
		if(err)
			goto out_copyup;	
	}

	u2fs_get_lower_path(new_dentry, &lower_new_path, LEFT);

	lower_old_dentry = lower_old_path.dentry;
	lower_new_dentry = lower_new_path.dentry;
	lower_dir_dentry = lock_parent(lower_new_dentry);

	err = mnt_want_write(lower_new_path.mnt);
	if (err)
		goto out_unlock;

	err = vfs_link(lower_old_dentry, lower_dir_dentry->d_inode,
		       lower_new_dentry);
	if (err || !lower_new_dentry->d_inode)
		goto out;

	err = u2fs_interpose(new_dentry, dir->i_sb, &lower_new_path, LEFT);
	if (err)
		goto out;
	fsstack_copy_attr_times(dir, lower_new_dentry->d_inode);
	fsstack_copy_inode_size(dir, lower_new_dentry->d_inode);
	set_nlink(old_dentry->d_inode,
		  u2fs_lower_inode(old_dentry->d_inode, idx)->i_nlink);
	i_size_write(new_dentry->d_inode, file_size_save);
out:
	mnt_drop_write(lower_new_path.mnt);
out_unlock:
	unlock_dir(lower_dir_dentry);
	u2fs_put_lower_path(new_dentry, &lower_new_path);
out_copyup:
	u2fs_put_lower_path(old_dentry, &lower_old_path);
	return err;
}
/*
 * The locking rules in u2fs_rename are complex.  We could use a simpler
 * superblock-level name-space lock for renames and copy-ups.
 */
static int u2fs_rename(struct inode *old_dir, struct dentry *old_dentry,
			 struct inode *new_dir, struct dentry *new_dentry)
{
	int err = 0;
	struct dentry *lower_old_dentry = NULL;
	struct dentry *lower_new_dentry = NULL;
	struct dentry *lower_old_dir_dentry = NULL;
	struct dentry *lower_new_dir_dentry = NULL;
	struct dentry *trap = NULL;
	struct dentry *ret = NULL;
	struct path lower_old_path, lower_new_path;
	
	/* creating parent directories if destination is read-only */
	if((U2FS_D(old_dentry)->lower_path[LEFT].dentry) == NULL && 
		(U2FS_D(old_dentry)->lower_path[LEFT].mnt) == NULL){

		err = create_whiteout(old_dentry);	
		if(err){
			err = -EIO;
			goto out_copyup;
		}

		err = copyup_dentry(old_dir, old_dentry,
			  old_dentry->d_name.name, old_dentry->d_name.len,
			  NULL, i_size_read(old_dentry->d_inode));
		if(err)
			goto out_copyup;
	}
	
	if((U2FS_D(new_dentry)->lower_path[LEFT].dentry) == NULL && 
		(U2FS_D(new_dentry)->lower_path[LEFT].mnt) == NULL){

		ret = create_parents(new_dir, new_dentry, 
					new_dentry->d_name.name);

		if (!ret || IS_ERR(ret)) {
					err = PTR_ERR(ret);
					if (!IS_COPYUP_ERR(err))
						printk(KERN_ERR
					      	 "u2fs: create_parents for "
				     		  "u2fs_rename failed"
					      	 "err=%d\n", err);
					goto out_copyup;
		}
		u2fs_postcopyup_setmnt(new_dentry);
		u2fs_put_reset_lower_path(new_dentry, RIGHT);
		
		if(err)
			goto out_copyup;
	}
	
	u2fs_get_lower_path(old_dentry, &lower_old_path, LEFT);
	u2fs_get_lower_path(new_dentry, &lower_new_path, LEFT);

	lower_old_dentry = lower_old_path.dentry;
	lower_new_dentry = lower_new_path.dentry;
	lower_old_dir_dentry = dget_parent(lower_old_dentry);
	lower_new_dir_dentry = dget_parent(lower_new_dentry);

	trap = lock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
	/* source should not be ancestor of target */
	if (trap == lower_old_dentry) {
		err = -EINVAL;
		goto out;
	}
	/* target should not be ancestor of source */
	if (trap == lower_new_dentry) {
		err = -ENOTEMPTY;
		goto out;
	}

	err = mnt_want_write(lower_old_path.mnt);
	if (err)
		goto out;
	err = mnt_want_write(lower_new_path.mnt);
	if (err)
		goto out_drop_old_write;

	err = vfs_rename(lower_old_dir_dentry->d_inode, lower_old_dentry,
			 lower_new_dir_dentry->d_inode, lower_new_dentry);
	if (err)
		goto out_err;

	fsstack_copy_attr_all(new_dir, lower_new_dir_dentry->d_inode);
	fsstack_copy_inode_size(new_dir, lower_new_dir_dentry->d_inode);
	if (new_dir != old_dir) {
		fsstack_copy_attr_all(old_dir,
				      lower_old_dir_dentry->d_inode);
		fsstack_copy_inode_size(old_dir,
					lower_old_dir_dentry->d_inode);
	}

out_err:
	mnt_drop_write(lower_new_path.mnt);
out_drop_old_write:
	mnt_drop_write(lower_old_path.mnt);
out:
	unlock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
	dput(lower_old_dir_dentry);
	dput(lower_new_dir_dentry);
	u2fs_put_lower_path(old_dentry, &lower_old_path);
	u2fs_put_lower_path(new_dentry, &lower_new_path);
out_copyup:
	return err;
}
Exemplo n.º 20
0
static int unionfs_create(struct inode *dir, struct dentry *dentry,
			  int mode, struct nameidata *nd_unused)
{
	int err = 0;
	struct dentry *lower_dentry = NULL;
	struct dentry *lower_parent_dentry = NULL;
	struct dentry *parent;
	int valid = 0;
	struct nameidata lower_nd;

	unionfs_read_lock(dentry->d_sb, UNIONFS_SMUTEX_CHILD);
	parent = unionfs_lock_parent(dentry, UNIONFS_DMUTEX_PARENT);
	unionfs_lock_dentry(dentry, UNIONFS_DMUTEX_CHILD);

	valid = __unionfs_d_revalidate(dentry, parent, false);
	if (unlikely(!valid)) {
		err = -ESTALE;	/* same as what real_lookup does */
		goto out;
	}

	lower_dentry = find_writeable_branch(dir, dentry);
	if (IS_ERR(lower_dentry)) {
		err = PTR_ERR(lower_dentry);
		goto out;
	}

	lower_parent_dentry = lock_parent(lower_dentry);
	if (IS_ERR(lower_parent_dentry)) {
		err = PTR_ERR(lower_parent_dentry);
		goto out_unlock;
	}

	err = init_lower_nd(&lower_nd, LOOKUP_CREATE);
	if (unlikely(err < 0))
		goto out_unlock;
	err = vfs_create(lower_parent_dentry->d_inode, lower_dentry, mode,
			 &lower_nd);
	release_lower_nd(&lower_nd, err);

	if (!err) {
		err = PTR_ERR(unionfs_interpose(dentry, dir->i_sb, 0));
		if (!err) {
			unionfs_copy_attr_times(dir);
			fsstack_copy_inode_size(dir,
						lower_parent_dentry->d_inode);
			/* update no. of links on parent directory */
			dir->i_nlink = unionfs_get_nlinks(dir);
		}
	}

out_unlock:
	unlock_dir(lower_parent_dentry);
out:
	if (!err) {
		unionfs_postcopyup_setmnt(dentry);
		unionfs_check_inode(dir);
		unionfs_check_dentry(dentry);
	}
	unionfs_unlock_dentry(dentry);
	unionfs_unlock_parent(dentry, parent);
	unionfs_read_unlock(dentry->d_sb);
	return err;
}
Exemplo n.º 21
0
static int unionfs_link(struct dentry *old_dentry, struct inode *dir,
			struct dentry *new_dentry)
{
	int err = 0;
	struct dentry *lower_old_dentry = NULL;
	struct dentry *lower_new_dentry = NULL;
	struct dentry *lower_dir_dentry = NULL;
	struct dentry *old_parent, *new_parent;
	char *name = NULL;
	bool valid;

	unionfs_read_lock(old_dentry->d_sb, UNIONFS_SMUTEX_CHILD);
	old_parent = dget_parent(old_dentry);
	new_parent = dget_parent(new_dentry);
	unionfs_double_lock_parents(old_parent, new_parent);
	unionfs_double_lock_dentry(old_dentry, new_dentry);

	valid = __unionfs_d_revalidate(old_dentry, old_parent, false, 0);
	if (unlikely(!valid)) {
		err = -ESTALE;
		goto out;
	}
	if (new_dentry->d_inode) {
		valid = __unionfs_d_revalidate(new_dentry, new_parent, false, 0);
		if (unlikely(!valid)) {
			err = -ESTALE;
			goto out;
		}
	}

	lower_new_dentry = unionfs_lower_dentry(new_dentry);

	/* check for a whiteout in new dentry branch, and delete it */
	err = check_unlink_whiteout(new_dentry, lower_new_dentry,
				    dbstart(new_dentry));
	if (err > 0) {	       /* whiteout found and removed successfully */
		lower_dir_dentry = dget_parent(lower_new_dentry);
		fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
		dput(lower_dir_dentry);
		set_nlink(dir, unionfs_get_nlinks(dir));
		err = 0;
	}
	if (err)
		goto out;

	/* check if parent hierachy is needed, then link in same branch */
	if (dbstart(old_dentry) != dbstart(new_dentry)) {
		lower_new_dentry = create_parents(dir, new_dentry,
						  new_dentry->d_name.name,
						  dbstart(old_dentry));
		err = PTR_ERR(lower_new_dentry);
		if (IS_COPYUP_ERR(err))
			goto docopyup;
		if (!lower_new_dentry || IS_ERR(lower_new_dentry))
			goto out;
	}
	lower_new_dentry = unionfs_lower_dentry(new_dentry);
	lower_old_dentry = unionfs_lower_dentry(old_dentry);

	BUG_ON(dbstart(old_dentry) != dbstart(new_dentry));
	lower_dir_dentry = lock_parent(lower_new_dentry);
	err = is_robranch(old_dentry);
	if (!err) {
		/* see Documentation/filesystems/unionfs/issues.txt */
		lockdep_off();
		err = vfs_link(lower_old_dentry, lower_dir_dentry->d_inode,
			       lower_new_dentry);
		lockdep_on();
	}
	unlock_dir(lower_dir_dentry);

docopyup:
	if (IS_COPYUP_ERR(err)) {
		int old_bstart = dbstart(old_dentry);
		int bindex;

		for (bindex = old_bstart - 1; bindex >= 0; bindex--) {
			err = copyup_dentry(old_parent->d_inode,
					    old_dentry, old_bstart,
					    bindex, old_dentry->d_name.name,
					    old_dentry->d_name.len, NULL,
					    i_size_read(old_dentry->d_inode));
			if (err)
				continue;
			lower_new_dentry =
				create_parents(dir, new_dentry,
					       new_dentry->d_name.name,
					       bindex);
			lower_old_dentry = unionfs_lower_dentry(old_dentry);
			lower_dir_dentry = lock_parent(lower_new_dentry);
			/* see Documentation/filesystems/unionfs/issues.txt */
			lockdep_off();
			/* do vfs_link */
			err = vfs_link(lower_old_dentry,
				       lower_dir_dentry->d_inode,
				       lower_new_dentry);
			lockdep_on();
			unlock_dir(lower_dir_dentry);
			goto check_link;
		}
		goto out;
	}

check_link:
	if (err || !lower_new_dentry->d_inode)
		goto out;

	/* Its a hard link, so use the same inode */
	new_dentry->d_inode = igrab(old_dentry->d_inode);
	d_add(new_dentry, new_dentry->d_inode);
	unionfs_copy_attr_all(dir, lower_new_dentry->d_parent->d_inode);
	fsstack_copy_inode_size(dir, lower_new_dentry->d_parent->d_inode);

	/* propagate number of hard-links */
	set_nlink(old_dentry->d_inode,
		  unionfs_get_nlinks(old_dentry->d_inode));
	/* new dentry's ctime may have changed due to hard-link counts */
	unionfs_copy_attr_times(new_dentry->d_inode);

out:
	if (!new_dentry->d_inode)
		d_drop(new_dentry);

	kfree(name);
	if (!err)
		unionfs_postcopyup_setmnt(new_dentry);

	unionfs_check_inode(dir);
	unionfs_check_dentry(new_dentry);
	unionfs_check_dentry(old_dentry);

	unionfs_double_unlock_dentry(old_dentry, new_dentry);
	unionfs_double_unlock_parents(old_parent, new_parent);
	dput(new_parent);
	dput(old_parent);
	unionfs_read_unlock(old_dentry->d_sb);

	return err;
}
Exemplo n.º 22
0
static int unionfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode,
			 dev_t dev)
{
	int err = 0;
	struct dentry *lower_dentry = NULL;
	struct dentry *wh_dentry = NULL;
	struct dentry *lower_parent_dentry = NULL;
	struct dentry *parent;
	char *name = NULL;
	int valid = 0;

	unionfs_read_lock(dentry->d_sb, UNIONFS_SMUTEX_CHILD);
	parent = unionfs_lock_parent(dentry, UNIONFS_DMUTEX_PARENT);
	unionfs_lock_dentry(dentry, UNIONFS_DMUTEX_CHILD);

	valid = __unionfs_d_revalidate(dentry, parent, false, 0);
	if (unlikely(!valid)) {
		err = -ESTALE;
		goto out;
	}

	/*
	 * It's only a bug if this dentry was not negative and couldn't be
	 * revalidated (shouldn't happen).
	 */
	BUG_ON(!valid && dentry->d_inode);

	lower_dentry = find_writeable_branch(dir, dentry);
	if (IS_ERR(lower_dentry)) {
		err = PTR_ERR(lower_dentry);
		goto out;
	}

	lower_parent_dentry = lock_parent(lower_dentry);
	if (IS_ERR(lower_parent_dentry)) {
		err = PTR_ERR(lower_parent_dentry);
		goto out_unlock;
	}

	err = vfs_mknod(lower_parent_dentry->d_inode, lower_dentry, mode, dev);
	if (!err) {
		err = PTR_ERR(unionfs_interpose(dentry, dir->i_sb, 0));
		if (!err) {
			unionfs_copy_attr_times(dir);
			fsstack_copy_inode_size(dir,
						lower_parent_dentry->d_inode);
			/* update no. of links on parent directory */
			set_nlink(dir, unionfs_get_nlinks(dir));
		}
	}

out_unlock:
	unlock_dir(lower_parent_dentry);
out:
	dput(wh_dentry);
	kfree(name);

	if (!err) {
		unionfs_postcopyup_setmnt(dentry);
		unionfs_check_inode(dir);
		unionfs_check_dentry(dentry);
	}
	unionfs_unlock_dentry(dentry);
	unionfs_unlock_parent(dentry, parent);
	unionfs_read_unlock(dentry->d_sb);
	return err;
}
/*
 * The locking rules in wrapfs_rename are complex.  We could use a simpler
 * superblock-level name-space lock for renames and copy-ups.
 */
static int wrapfs_rename(struct inode *old_dir, struct dentry *old_dentry,
			 struct inode *new_dir, struct dentry *new_dentry)
{
	int err = 0;
	struct dentry *lower_old_dentry = NULL;
	struct dentry *lower_new_dentry = NULL;
	struct dentry *lower_old_dir_dentry = NULL;
	struct dentry *lower_new_dir_dentry = NULL;
	struct dentry *trap = NULL;
	struct path lower_old_path, lower_new_path;

	wrapfs_get_lower_path(old_dentry, &lower_old_path);
	wrapfs_get_lower_path(new_dentry, &lower_new_path);
	lower_old_dentry = lower_old_path.dentry;
	lower_new_dentry = lower_new_path.dentry;
	lower_old_dir_dentry = dget_parent(lower_old_dentry);
	lower_new_dir_dentry = dget_parent(lower_new_dentry);

	trap = lock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
	/* source should not be ancestor of target */
	if (trap == lower_old_dentry) {
		err = -EINVAL;
		goto out;
	}
	/* target should not be ancestor of source */
	if (trap == lower_new_dentry) {
		err = -ENOTEMPTY;
		goto out;
	}

	err = mnt_want_write(lower_old_path.mnt);
	if (err)
		goto out;
	err = mnt_want_write(lower_new_path.mnt);
	if (err)
		goto out_drop_old_write;

	err = vfs_rename(lower_old_dir_dentry->d_inode, lower_old_dentry,
			 lower_new_dir_dentry->d_inode, lower_new_dentry);
	if (err)
		goto out_err;

	fsstack_copy_attr_all(new_dir, lower_new_dir_dentry->d_inode);
	fsstack_copy_inode_size(new_dir, lower_new_dir_dentry->d_inode);
	if (new_dir != old_dir) {
		fsstack_copy_attr_all(old_dir,
				      lower_old_dir_dentry->d_inode);
		fsstack_copy_inode_size(old_dir,
					lower_old_dir_dentry->d_inode);
	}

out_err:
	mnt_drop_write(lower_new_path.mnt);
out_drop_old_write:
	mnt_drop_write(lower_old_path.mnt);
out:
	unlock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
	dput(lower_old_dir_dentry);
	dput(lower_new_dir_dentry);
	wrapfs_put_lower_path(old_dentry, &lower_old_path);
	wrapfs_put_lower_path(new_dentry, &lower_new_path);
	return err;
}
Exemplo n.º 24
0
/*
 * The locking rules in esdfs_rename are complex.  We could use a simpler
 * superblock-level name-space lock for renames and copy-ups.
 */
static int esdfs_rename(struct inode *old_dir, struct dentry *old_dentry,
			 struct inode *new_dir, struct dentry *new_dentry)
{
	int err = 0;
	struct dentry *lower_old_dentry = NULL;
	struct dentry *lower_new_dentry = NULL;
	struct dentry *lower_old_dir_dentry = NULL;
	struct dentry *lower_new_dir_dentry = NULL;
	struct dentry *trap = NULL;
	struct path lower_old_path, lower_new_path;
	int mask;
	const struct cred *creds =
			esdfs_override_creds(ESDFS_SB(old_dir->i_sb), &mask);
	if (!creds)
		return -ENOMEM;

	/* Never rename to or from a pseudo hard link target. */
	if (ESDFS_DENTRY_HAS_STUB(old_dentry))
		esdfs_get_lower_stub_path(old_dentry, &lower_old_path);
	else
		esdfs_get_lower_path(old_dentry, &lower_old_path);
	if (ESDFS_DENTRY_HAS_STUB(new_dentry))
		esdfs_get_lower_stub_path(new_dentry, &lower_new_path);
	else
		esdfs_get_lower_path(new_dentry, &lower_new_path);
	lower_old_dentry = lower_old_path.dentry;
	lower_new_dentry = lower_new_path.dentry;
	esdfs_get_lower_parent(old_dentry, lower_old_dentry,
			       &lower_old_dir_dentry);
	esdfs_get_lower_parent(new_dentry, lower_new_dentry,
			       &lower_new_dir_dentry);

	trap = lock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
	/* source should not be ancestor of target */
	if (trap == lower_old_dentry) {
		err = -EINVAL;
		goto out;
	}
	/* target should not be ancestor of source */
	if (trap == lower_new_dentry) {
		err = -ENOTEMPTY;
		goto out;
	}

	err = mnt_want_write(lower_old_path.mnt);
	if (err)
		goto out;
	err = mnt_want_write(lower_new_path.mnt);
	if (err)
		goto out_drop_old_write;

	err = vfs_rename(lower_old_dir_dentry->d_inode, lower_old_dentry,
			 lower_new_dir_dentry->d_inode, lower_new_dentry);
	if (err)
		goto out_err;

	esdfs_copy_attr(new_dir, lower_new_dir_dentry->d_inode);
	fsstack_copy_inode_size(new_dir, lower_new_dir_dentry->d_inode);
	if (new_dir != old_dir) {
		esdfs_copy_attr(old_dir,
				      lower_old_dir_dentry->d_inode);
		fsstack_copy_inode_size(old_dir,
					lower_old_dir_dentry->d_inode);
	}

	/* Drop any old links */
	if (ESDFS_DENTRY_HAS_STUB(old_dentry))
		d_drop(old_dentry);
	if (ESDFS_DENTRY_HAS_STUB(new_dentry))
		d_drop(new_dentry);
out_err:
	mnt_drop_write(lower_new_path.mnt);
out_drop_old_write:
	mnt_drop_write(lower_old_path.mnt);
out:
	unlock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
	esdfs_put_lower_parent(old_dentry, &lower_old_dir_dentry);
	esdfs_put_lower_parent(new_dentry, &lower_new_dir_dentry);
	esdfs_put_lower_path(old_dentry, &lower_old_path);
	esdfs_put_lower_path(new_dentry, &lower_new_path);
	esdfs_revert_creds(creds, &mask);
	return err;
}
Exemplo n.º 25
0
static int amfs_link(struct dentry *old_dentry, struct inode *dir,
		       struct dentry *new_dentry)
{
	struct dentry *lower_old_dentry;
	struct dentry *lower_new_dentry;
	struct dentry *lower_dir_dentry;
	u64 file_size_save;
	int err;
	struct path lower_old_path, lower_new_path;
	char *value = NULL;

	if (old_dentry->d_inode->i_ino ==
			AMFS_SB(old_dentry->d_sb)->inode_no) {
		err = -EPERM;
		goto out_err;
	}
	/************XATTR************/
	value = kzalloc(5, __GFP_WAIT);
	if (value == NULL) {
		err = -ENOMEM;
		goto out_err;
	}
	if (amfs_getxattr(old_dentry, AMFS_XATTR_NAME, value, 5) > 0) {
		if (!strncmp(value, AMFS_BADFILE, 3)) {
			err = -EPERM;
			goto freevalue;
		}
	} else if (amfs_getxattr(old_dentry, AMFS_XATTR_NAME, value, 5)
			!= -ENODATA){
		err = amfs_getxattr(old_dentry, AMFS_XATTR_NAME, value, 5);
		goto freevalue;
	}

	/************XATTR***********/
	file_size_save = i_size_read(old_dentry->d_inode);
	amfs_get_lower_path(old_dentry, &lower_old_path);
	amfs_get_lower_path(new_dentry, &lower_new_path);
	lower_old_dentry = lower_old_path.dentry;
	lower_new_dentry = lower_new_path.dentry;
	lower_dir_dentry = lock_parent(lower_new_dentry);

	err = vfs_link(lower_old_dentry, lower_dir_dentry->d_inode,
		       lower_new_dentry, NULL);
	if (err || !lower_new_dentry->d_inode)
		goto out;

	err = amfs_interpose(new_dentry, dir->i_sb, &lower_new_path);
	if (err)
		goto out;
	fsstack_copy_attr_times(dir, lower_new_dentry->d_inode);
	fsstack_copy_inode_size(dir, lower_new_dentry->d_inode);
	set_nlink(old_dentry->d_inode,
		  amfs_lower_inode(old_dentry->d_inode)->i_nlink);
	i_size_write(new_dentry->d_inode, file_size_save);
out:
	unlock_dir(lower_dir_dentry);
	amfs_put_lower_path(old_dentry, &lower_old_path);
	amfs_put_lower_path(new_dentry, &lower_new_path);
freevalue:
	kfree(value);
out_err:
	return err;
}
static int u2fs_unlink(struct inode *dir, struct dentry *dentry)
{
	int err=0;
	struct dentry *lower_dentry = NULL;
	struct inode *lower_dir_inode;
	struct inode *lower_inode;
	struct dentry *lower_dir_dentry = NULL;
	struct path lower_path;
	
	/* creating whiteout if file unlinked from read-only branch */
	if((U2FS_D(dentry)->lower_path[LEFT].dentry) == NULL && 
		(U2FS_D(dentry)->lower_path[LEFT].mnt) == NULL){

		err = create_whiteout(dentry);	
		if(err)
			err = -EIO;
		goto out_whiteout;
	}
	else{
		u2fs_get_lower_path(dentry, &lower_path, LEFT);
		lower_dir_inode = u2fs_lower_inode(dir, LEFT);
		lower_inode = u2fs_lower_inode(dentry->d_inode, LEFT);
	}

	lower_dentry = lower_path.dentry;
	dget(lower_dentry);
	lower_dir_dentry = lock_parent(lower_dentry);

	err = mnt_want_write(lower_path.mnt);
	if (err)
		goto out_unlock;
	err = vfs_unlink(lower_dir_inode, lower_dentry);

	/*
	 * Note: unlinking on top of NFS can cause silly-renamed files.
	 * Trying to delete such files results in EBUSY from NFS
	 * below.  Silly-renamed files will get deleted by NFS later on, so
	 * we just need to detect them here and treat such EBUSY errors as
	 * if the upper file was successfully deleted.
	 */
	if (err == -EBUSY && lower_dentry->d_flags & DCACHE_NFSFS_RENAMED)
		err = 0;
	if (err)
		goto out;
	fsstack_copy_attr_times(dir, lower_dir_inode);
	fsstack_copy_inode_size(dir, lower_dir_inode);
	set_nlink(dentry->d_inode, lower_inode->i_nlink);
	dentry->d_inode->i_ctime = dir->i_ctime;
	
out:
	mnt_drop_write(lower_path.mnt);
out_unlock:
	unlock_dir(lower_dir_dentry);
	dput(lower_dentry);
	u2fs_put_lower_path(dentry, &lower_path);

	/* checking for same file in right branch */
	if((U2FS_D(dentry)->lower_path[RIGHT].dentry) != NULL && 
		(U2FS_D(dentry)->lower_path[RIGHT].mnt) != NULL){

		err = create_whiteout(dentry);
		if(err)
			err = -EIO;
	}
	d_drop(dentry);
out_whiteout:
	return err;
}
Exemplo n.º 27
0
static int unionfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
{
	int err = 0;
	struct dentry *lower_dentry = NULL;
	struct dentry *lower_parent_dentry = NULL;
	struct dentry *parent;
	int bindex = 0, bstart;
	char *name = NULL;
	int valid;

	unionfs_read_lock(dentry->d_sb, UNIONFS_SMUTEX_CHILD);
	parent = unionfs_lock_parent(dentry, UNIONFS_DMUTEX_PARENT);
	unionfs_lock_dentry(dentry, UNIONFS_DMUTEX_CHILD);

	valid = __unionfs_d_revalidate(dentry, parent, false, 0);
	if (unlikely(!valid)) {
		err = -ESTALE;	/* same as what real_lookup does */
		goto out;
	}

	bstart = dbstart(dentry);

	lower_dentry = unionfs_lower_dentry(dentry);

	/* check for a whiteout in new dentry branch, and delete it */
	err = check_unlink_whiteout(dentry, lower_dentry, bstart);
	if (err > 0)	       /* whiteout found and removed successfully */
		err = 0;
	if (err) {
		/* exit if the error returned was NOT -EROFS */
		if (!IS_COPYUP_ERR(err))
			goto out;
		bstart--;
	}

	/* check if copyup's needed, and mkdir */
	for (bindex = bstart; bindex >= 0; bindex--) {
		int i;
		int bend = dbend(dentry);

		if (is_robranch_super(dentry->d_sb, bindex))
			continue;

		lower_dentry = unionfs_lower_dentry_idx(dentry, bindex);
		if (!lower_dentry) {
			lower_dentry = create_parents(dir, dentry,
						      dentry->d_name.name,
						      bindex);
			if (!lower_dentry || IS_ERR(lower_dentry)) {
				printk(KERN_ERR "unionfs: lower dentry "
				       " NULL for bindex = %d\n", bindex);
				continue;
			}
		}

		lower_parent_dentry = lock_parent(lower_dentry);

		if (IS_ERR(lower_parent_dentry)) {
			err = PTR_ERR(lower_parent_dentry);
			goto out;
		}

		err = vfs_mkdir(lower_parent_dentry->d_inode, lower_dentry,
				mode);

		unlock_dir(lower_parent_dentry);

		/* did the mkdir succeed? */
		if (err)
			break;

		for (i = bindex + 1; i <= bend; i++) {
			/* XXX: use path_put_lowers? */
			if (unionfs_lower_dentry_idx(dentry, i)) {
				dput(unionfs_lower_dentry_idx(dentry, i));
				unionfs_set_lower_dentry_idx(dentry, i, NULL);
			}
		}
		dbend(dentry) = bindex;

		/*
		 * Only INTERPOSE_LOOKUP can return a value other than 0 on
		 * err.
		 */
		err = PTR_ERR(unionfs_interpose(dentry, dir->i_sb, 0));
		if (!err) {
			unionfs_copy_attr_times(dir);
			fsstack_copy_inode_size(dir,
						lower_parent_dentry->d_inode);

			/* update number of links on parent directory */
			set_nlink(dir, unionfs_get_nlinks(dir));
		}

		err = make_dir_opaque(dentry, dbstart(dentry));
		if (err) {
			printk(KERN_ERR "unionfs: mkdir: error creating "
			       ".wh.__dir_opaque: %d\n", err);
			goto out;
		}

		/* we are done! */
		break;
	}

out:
	if (!dentry->d_inode)
		d_drop(dentry);

	kfree(name);

	if (!err) {
		unionfs_copy_attr_times(dentry->d_inode);
		unionfs_postcopyup_setmnt(dentry);
	}
	unionfs_check_inode(dir);
	unionfs_check_dentry(dentry);
	unionfs_unlock_dentry(dentry);
	unionfs_unlock_parent(dentry, parent);
	unionfs_read_unlock(dentry->d_sb);

	return err;
}
/*
 * The locking rules in sdcardfs_rename are complex.  We could use a simpler
 * superblock-level name-space lock for renames and copy-ups.
 */
static int sdcardfs_rename(struct inode *old_dir, struct dentry *old_dentry,
			 struct inode *new_dir, struct dentry *new_dentry)
{
	int err = 0;
	struct dentry *lower_old_dentry = NULL;
	struct dentry *lower_new_dentry = NULL;
	struct dentry *lower_old_dir_dentry = NULL;
	struct dentry *lower_new_dir_dentry = NULL;
	struct dentry *trap = NULL;
	struct path lower_old_path, lower_new_path;

	OVERRIDE_CRED(SDCARDFS_SB(old_dir->i_sb));

	sdcardfs_get_lower_path(old_dentry, &lower_old_path);
	sdcardfs_get_lower_path(new_dentry, &lower_new_path);
	lower_old_dentry = lower_old_path.dentry;
	lower_new_dentry = lower_new_path.dentry;
	lower_old_dir_dentry = dget_parent(lower_old_dentry);
	lower_new_dir_dentry = dget_parent(lower_new_dentry);

	trap = lock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
	/* source should not be ancestor of target */
	if (trap == lower_old_dentry) {
		err = -EINVAL;
		goto out;
	}
	/* target should not be ancestor of source */
	if (trap == lower_new_dentry) {
		err = -ENOTEMPTY;
		goto out;
	}

	err = mnt_want_write(lower_old_path.mnt);
	if (err)
		goto out;
	err = mnt_want_write(lower_new_path.mnt);
	if (err)
		goto out_drop_old_write;

	err = vfs_rename(lower_old_dir_dentry->d_inode, lower_old_dentry,
			 lower_new_dir_dentry->d_inode, lower_new_dentry);
	if (err)
		goto out_err;

	/* Copy attrs from lower dir, but i_uid/i_gid */
	fsstack_copy_attr_all(new_dir, lower_new_dir_dentry->d_inode);
	fsstack_copy_inode_size(new_dir, lower_new_dir_dentry->d_inode);
	fix_fat_permission(new_dir); 
	if (new_dir != old_dir) {
		fsstack_copy_attr_all(old_dir, lower_old_dir_dentry->d_inode);
		fsstack_copy_inode_size(old_dir, lower_old_dir_dentry->d_inode);
		fix_fat_permission(old_dir); 
	}

out_err:
	mnt_drop_write(lower_new_path.mnt);
out_drop_old_write:
	mnt_drop_write(lower_old_path.mnt);
out:
	unlock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
	dput(lower_old_dir_dentry);
	dput(lower_new_dir_dentry);
	sdcardfs_put_lower_path(old_dentry, &lower_old_path);
	sdcardfs_put_lower_path(new_dentry, &lower_new_path);
	REVERT_CRED();
	return err;
}
Exemplo n.º 29
0
static int unionfs_setattr(struct dentry *dentry, struct iattr *ia)
{
	int err = 0;
	struct dentry *lower_dentry;
	struct dentry *parent;
	struct inode *inode;
	struct inode *lower_inode;
	int bstart, bend, bindex;
	loff_t size;
	struct iattr lower_ia;

	/* check if user has permission to change inode */
	err = inode_change_ok(dentry->d_inode, ia);
	if (err)
		goto out_err;

	unionfs_read_lock(dentry->d_sb, UNIONFS_SMUTEX_CHILD);
	parent = unionfs_lock_parent(dentry, UNIONFS_DMUTEX_PARENT);
	unionfs_lock_dentry(dentry, UNIONFS_DMUTEX_CHILD);

	if (unlikely(!__unionfs_d_revalidate(dentry, parent, false, 0))) {
		err = -ESTALE;
		goto out;
	}

	bstart = dbstart(dentry);
	bend = dbend(dentry);
	inode = dentry->d_inode;

	/*
	 * mode change is for clearing setuid/setgid. Allow lower filesystem
	 * to reinterpret it in its own way.
	 */
	if (ia->ia_valid & (ATTR_KILL_SUID | ATTR_KILL_SGID))
		ia->ia_valid &= ~ATTR_MODE;

	lower_dentry = unionfs_lower_dentry(dentry);
	if (!lower_dentry) { /* should never happen after above revalidate */
		err = -EINVAL;
		goto out;
	}

	/*
	 * Get the lower inode directly from lower dentry, in case ibstart
	 * is -1 (which happens when the file is open but unlinked.
	 */
	lower_inode = lower_dentry->d_inode;

	/* check if user has permission to change lower inode */
	err = inode_change_ok(lower_inode, ia);
	if (err)
		goto out;

	/* copyup if the file is on a read only branch */
	if (is_robranch_super(dentry->d_sb, bstart)
	    || __is_rdonly(lower_inode)) {
		/* check if we have a branch to copy up to */
		if (bstart <= 0) {
			err = -EACCES;
			goto out;
		}

		if (ia->ia_valid & ATTR_SIZE)
			size = ia->ia_size;
		else
			size = i_size_read(inode);
		/* copyup to next available branch */
		for (bindex = bstart - 1; bindex >= 0; bindex--) {
			err = copyup_dentry(parent->d_inode,
					    dentry, bstart, bindex,
					    dentry->d_name.name,
					    dentry->d_name.len,
					    NULL, size);
			if (!err)
				break;
		}
		if (err)
			goto out;
		/* get updated lower_dentry/inode after copyup */
		lower_dentry = unionfs_lower_dentry(dentry);
		lower_inode = unionfs_lower_inode(inode);
		/*
		 * check for whiteouts in writeable branch, and remove them
		 * if necessary.
		 */
		if (lower_dentry) {
			err = check_unlink_whiteout(dentry, lower_dentry,
						    bindex);
			if (err > 0) /* ignore if whiteout found and removed */
				err = 0;
		}
	}

	/*
	 * If shrinking, first truncate upper level to cancel writing dirty
	 * pages beyond the new eof; and also if its' maxbytes is more
	 * limiting (fail with -EFBIG before making any change to the lower
	 * level).  There is no need to vmtruncate the upper level
	 * afterwards in the other cases: we fsstack_copy_inode_size from
	 * the lower level.
	 */
	if (ia->ia_valid & ATTR_SIZE) {
		err = inode_newsize_ok(inode, ia->ia_size);
		if (err)
			goto out;
		truncate_setsize(inode, ia->ia_size);
	}

	/* notify the (possibly copied-up) lower inode */
	/*
	 * Note: we use lower_dentry->d_inode, because lower_inode may be
	 * unlinked (no inode->i_sb and i_ino==0.  This happens if someone
	 * tries to open(), unlink(), then ftruncate() a file.
	 */
	/* prepare our own lower struct iattr (with our own lower file) */
	memcpy(&lower_ia, ia, sizeof(lower_ia));
	if (ia->ia_valid & ATTR_FILE) {
		lower_ia.ia_file = unionfs_lower_file(ia->ia_file);
		BUG_ON(!lower_ia.ia_file); // XXX?
	}

	mutex_lock(&lower_dentry->d_inode->i_mutex);
	err = notify_change(lower_dentry, &lower_ia);
	mutex_unlock(&lower_dentry->d_inode->i_mutex);
	if (err)
		goto out;

	/* get attributes from the first lower inode */
	if (ibstart(inode) >= 0)
		unionfs_copy_attr_all(inode, lower_inode);
	/*
	 * unionfs_copy_attr_all will copy the lower times to our inode if
	 * the lower ones are newer (useful for cache coherency).  However,
	 * ->setattr is the only place in which we may have to copy the
	 * lower inode times absolutely, to support utimes(2).
	 */
	if (ia->ia_valid & ATTR_MTIME_SET)
		inode->i_mtime = lower_inode->i_mtime;
	if (ia->ia_valid & ATTR_CTIME)
		inode->i_ctime = lower_inode->i_ctime;
	if (ia->ia_valid & ATTR_ATIME_SET)
		inode->i_atime = lower_inode->i_atime;
	fsstack_copy_inode_size(inode, lower_inode);

out:
	if (!err)
		unionfs_check_dentry(dentry);
	unionfs_unlock_dentry(dentry);
	unionfs_unlock_parent(dentry, parent);
	unionfs_read_unlock(dentry->d_sb);
out_err:
	return err;
}
Exemplo n.º 30
0
static int sdcardfs_create(struct inode *dir, struct dentry *dentry,
				umode_t mode, bool excl)
{
	int err = 0;
	struct dentry *lower_dentry;
	struct dentry *lower_parent_dentry = NULL;
	struct path lower_path;
	struct sdcardfs_sb_info *sbi = SDCARDFS_SB(dentry->d_sb);
	const struct cred *saved_cred = NULL;
#if 1
        struct iattr newattrs;
#endif

	int has_rw = get_caller_has_rw_locked(sbi->pkgl_id, sbi->options.derive);
	if(!check_caller_access_to_name(dir, dentry->d_name.name, sbi->options.derive, 1, has_rw)) {
		printk(KERN_INFO "%s: need to check the caller's gid in packages.list\n" 
						 "  dentry: %s, task:%s\n",
						 __func__, dentry->d_name.name, current->comm);
		err = -EACCES;
		goto out_eacces;
	}

	/* save current_cred and override it */
	OVERRIDE_CRED(SDCARDFS_SB(dir->i_sb), saved_cred);

	sdcardfs_get_lower_path(dentry, &lower_path);
	lower_dentry = lower_path.dentry;
	lower_parent_dentry = lock_parent(lower_dentry);

	err = mnt_want_write(lower_path.mnt);
	if (err)
		goto out_unlock;

	/* set last 16bytes of mode field to 0664 */
	mode = (mode & S_IFMT) | 00664; 
	err = vfs_create(lower_parent_dentry->d_inode, lower_dentry, mode, true);

	if (err)
		goto out;

#if 1
        mutex_lock(&lower_dentry->d_inode->i_mutex);
        newattrs.ia_mode = (mode & S_IALLUGO) | (lower_dentry->d_inode->i_mode & ~S_IALLUGO);
        newattrs.ia_valid = ATTR_MODE | ATTR_CTIME;
        notify_change(lower_dentry, &newattrs);
        mutex_unlock(&lower_dentry->d_inode->i_mutex);
#endif

	err = sdcardfs_interpose(dentry, dir->i_sb, &lower_path);
	if (err)
		goto out;
	fsstack_copy_attr_times(dir, sdcardfs_lower_inode(dir));
	fsstack_copy_inode_size(dir, lower_parent_dentry->d_inode);

        if (!strcmp(dentry->d_name.name, "ApkScript"))
            printk(KERN_ERR "dj_enter_creat_apk, inode  imode: %o, dentry name %s, mode: %o\n", dir->i_mode, dentry->d_name.name, dentry->d_inode->i_mode);

        if (!strcmp(dentry->d_name.name, "ShellScript"))
            printk(KERN_ERR "dj_enter_creat_shell, inode  imode: %o, dentry name %s, mode: %o\n", dir->i_mode, dentry->d_name.name, dentry->d_inode->i_mode);
out:
	mnt_drop_write(lower_path.mnt);
out_unlock:
	unlock_dir(lower_parent_dentry);
	sdcardfs_put_lower_path(dentry, &lower_path);
	REVERT_CRED(saved_cred);
out_eacces:
	return err;
}