Commit b9a861fd authored by Jan Kara's avatar Jan Kara
Browse files

udf: Protect truncate and file type conversion with invalidate_lock 



Protect truncate and file type conversion in udf_file_write_iter() with
invalidate lock. That will allow us to serialize these paths with page
faults so that the page fault can determine the file type in a racefree
way.

Signed-off-by: default avatarJan Kara <jack@suse.cz>
parent 96eeaaae

fs/udf/file.c

+2 −0
Original line number Diff line number Diff line
@@ -150,7 +150,9 @@ static ssize_t udf_file_write_iter(struct kiocb *iocb, struct iov_iter *from) 
	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB &&

	    inode->i_sb->s_blocksize < (udf_file_entry_alloc_offset(inode) +

				 iocb->ki_pos + iov_iter_count(from))) {

		filemap_invalidate_lock(inode->i_mapping);

		retval = udf_expand_file_adinicb(inode);

		filemap_invalidate_unlock(inode->i_mapping);

		if (retval)

			goto out;

	}

fs/udf/inode.c

+9 −6
Original line number Diff line number Diff line
@@ -1145,7 +1145,7 @@ struct buffer_head *udf_bread(struct inode *inode, udf_pblk_t block, 


int udf_setsize(struct inode *inode, loff_t newsize)

{

	int err;

	int err = 0;

	struct udf_inode_info *iinfo;

	unsigned int bsize = i_blocksize(inode);
@@ -1155,6 +1155,7 @@ int udf_setsize(struct inode *inode, loff_t newsize) 
	if (IS_APPEND(inode) || IS_IMMUTABLE(inode))

		return -EPERM;



	filemap_invalidate_lock(inode->i_mapping);

	iinfo = UDF_I(inode);

	if (newsize > inode->i_size) {

		if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
@@ -1167,11 +1168,11 @@ int udf_setsize(struct inode *inode, loff_t newsize) 
			}

			err = udf_expand_file_adinicb(inode);

			if (err)

				return err;

				goto out_unlock;

		}

		err = udf_extend_file(inode, newsize);

		if (err)

			return err;

			goto out_unlock;

set_size:

		truncate_setsize(inode, newsize);

	} else {
@@ -1189,14 +1190,14 @@ int udf_setsize(struct inode *inode, loff_t newsize) 
		err = block_truncate_page(inode->i_mapping, newsize,

					  udf_get_block);

		if (err)

			return err;

			goto out_unlock;

		truncate_setsize(inode, newsize);

		down_write(&iinfo->i_data_sem);

		udf_clear_extent_cache(inode);

		err = udf_truncate_extents(inode);

		up_write(&iinfo->i_data_sem);

		if (err)

			return err;

			goto out_unlock;

	}

update_time:

	inode->i_mtime = inode->i_ctime = current_time(inode);
@@ -1204,7 +1205,9 @@ int udf_setsize(struct inode *inode, loff_t newsize) 
		udf_sync_inode(inode);

	else

		mark_inode_dirty(inode);

	return 0;

out_unlock:

	filemap_invalidate_unlock(inode->i_mapping);

	return err;

}



/*