Commit c5b8d0bc authored by Christoph Hellwig's avatar Christoph Hellwig
Browse files

hfsplus: fix failed mount handling 



Currently the error handling in hfsplus_fill_super is a mess, and can
lead to accessing fields in the superblock that haven't been even set
up yet.  Fix this by making sure we do not set up sb->s_root until we
have the mount fully set up, and before that do proper step by step
unwinding instead of using hfsplus_put_super as a big hammer.

Reported-by: default avatarDan Williams <dcbw@redhat.com>
Signed-off-by: default avatarChristoph Hellwig <hch@tuxera.com>
parent ebf53826

fs/hfsplus/super.c

+61 −45
Original line number Diff line number Diff line
@@ -338,20 +338,22 @@ static int hfsplus_fill_super(struct super_block *sb, void *data, int silent) 
	struct inode *root, *inode;

	struct qstr str;

	struct nls_table *nls = NULL;

	int err = -EINVAL;

	int err;



	err = -EINVAL;

	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);

	if (!sbi)

		return -ENOMEM;

		goto out;



	sb->s_fs_info = sbi;

	mutex_init(&sbi->alloc_mutex);

	mutex_init(&sbi->vh_mutex);

	hfsplus_fill_defaults(sbi);



	err = -EINVAL;

	if (!hfsplus_parse_options(data, sbi)) {

		printk(KERN_ERR "hfs: unable to parse mount options\n");

		err = -EINVAL;

		goto cleanup;

		goto out_unload_nls;

	}



	/* temporarily use utf8 to correctly find the hidden dir below */
@@ -359,16 +361,14 @@ static int hfsplus_fill_super(struct super_block *sb, void *data, int silent) 
	sbi->nls = load_nls("utf8");

	if (!sbi->nls) {

		printk(KERN_ERR "hfs: unable to load nls for utf8\n");

		err = -EINVAL;

		goto cleanup;

		goto out_unload_nls;

	}



	/* Grab the volume header */

	if (hfsplus_read_wrapper(sb)) {

		if (!silent)

			printk(KERN_WARNING "hfs: unable to find HFS+ superblock\n");

		err = -EINVAL;

		goto cleanup;

		goto out_unload_nls;

	}

	vhdr = sbi->s_vhdr;
@@ -377,7 +377,7 @@ static int hfsplus_fill_super(struct super_block *sb, void *data, int silent) 
	if (be16_to_cpu(vhdr->version) < HFSPLUS_MIN_VERSION ||

	    be16_to_cpu(vhdr->version) > HFSPLUS_CURRENT_VERSION) {

		printk(KERN_ERR "hfs: wrong filesystem version\n");

		goto cleanup;

		goto out_free_vhdr;

	}

	sbi->total_blocks = be32_to_cpu(vhdr->total_blocks);

	sbi->free_blocks = be32_to_cpu(vhdr->free_blocks);
@@ -421,19 +421,19 @@ static int hfsplus_fill_super(struct super_block *sb, void *data, int silent) 
	sbi->ext_tree = hfs_btree_open(sb, HFSPLUS_EXT_CNID);

	if (!sbi->ext_tree) {

		printk(KERN_ERR "hfs: failed to load extents file\n");

		goto cleanup;

		goto out_free_vhdr;

	}

	sbi->cat_tree = hfs_btree_open(sb, HFSPLUS_CAT_CNID);

	if (!sbi->cat_tree) {

		printk(KERN_ERR "hfs: failed to load catalog file\n");

		goto cleanup;

		goto out_close_ext_tree;

	}



	inode = hfsplus_iget(sb, HFSPLUS_ALLOC_CNID);

	if (IS_ERR(inode)) {

		printk(KERN_ERR "hfs: failed to load allocation file\n");

		err = PTR_ERR(inode);

		goto cleanup;

		goto out_close_cat_tree;

	}

	sbi->alloc_file = inode;
@@ -442,14 +442,7 @@ static int hfsplus_fill_super(struct super_block *sb, void *data, int silent) 
	if (IS_ERR(root)) {

		printk(KERN_ERR "hfs: failed to load root directory\n");

		err = PTR_ERR(root);

		goto cleanup;

	}

	sb->s_d_op = &hfsplus_dentry_operations;

	sb->s_root = d_alloc_root(root);

	if (!sb->s_root) {

		iput(root);

		err = -ENOMEM;

		goto cleanup;

		goto out_put_alloc_file;

	}



	str.len = sizeof(HFSP_HIDDENDIR_NAME) - 1;
@@ -459,20 +452,19 @@ static int hfsplus_fill_super(struct super_block *sb, void *data, int silent) 
	if (!hfs_brec_read(&fd, &entry, sizeof(entry))) {

		hfs_find_exit(&fd);

		if (entry.type != cpu_to_be16(HFSPLUS_FOLDER))

			goto cleanup;

			goto out_put_root;

		inode = hfsplus_iget(sb, be32_to_cpu(entry.folder.id));

		if (IS_ERR(inode)) {

			err = PTR_ERR(inode);

			goto cleanup;

			goto out_put_root;

		}

		sbi->hidden_dir = inode;

	} else

		hfs_find_exit(&fd);



	if (sb->s_flags & MS_RDONLY)

		goto out;



	/* H+LX == hfsplusutils, H+Lx == this driver, H+lx is unused

	if (!(sb->s_flags & MS_RDONLY)) {

		/*

		 * H+LX == hfsplusutils, H+Lx == this driver, H+lx is unused

		 * all three are registered with Apple for our use

		 */

		vhdr->last_mount_vers = cpu_to_be32(HFSP_MOUNT_VERSION);
@@ -485,20 +477,44 @@ static int hfsplus_fill_super(struct super_block *sb, void *data, int silent) 
		if (!sbi->hidden_dir) {

			mutex_lock(&sbi->vh_mutex);

			sbi->hidden_dir = hfsplus_new_inode(sb, S_IFDIR);

		hfsplus_create_cat(sbi->hidden_dir->i_ino, sb->s_root->d_inode,

				   &str, sbi->hidden_dir);

			hfsplus_create_cat(sbi->hidden_dir->i_ino, root, &str,

					   sbi->hidden_dir);

			mutex_unlock(&sbi->vh_mutex);



		hfsplus_mark_inode_dirty(sbi->hidden_dir, HFSPLUS_I_CAT_DIRTY);

			hfsplus_mark_inode_dirty(sbi->hidden_dir,

						 HFSPLUS_I_CAT_DIRTY);

		}

out:

	}



	sb->s_d_op = &hfsplus_dentry_operations;

	sb->s_root = d_alloc_root(root);

	if (!sb->s_root) {

		err = -ENOMEM;

		goto out_put_hidden_dir;

	}



	unload_nls(sbi->nls);

	sbi->nls = nls;

	return 0;



cleanup:

	hfsplus_put_super(sb);

out_put_hidden_dir:

	iput(sbi->hidden_dir);

out_put_root:

	iput(sbi->alloc_file);

out_put_alloc_file:

	iput(sbi->alloc_file);

out_close_cat_tree:

	hfs_btree_close(sbi->cat_tree);

out_close_ext_tree:

	hfs_btree_close(sbi->ext_tree);

out_free_vhdr:

	kfree(sbi->s_vhdr);

	kfree(sbi->s_backup_vhdr);

out_unload_nls:

	unload_nls(sbi->nls);

	unload_nls(nls);

	kfree(sbi);

out:

	return err;

}

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