fs/ntfs3: Check reserved size for maximum allowed

Also don't mask EFBIG
Fixes xfstest generic/485
Fixes: 4342306f ("fs/ntfs3: Add file operations and implementation")
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>

fs/ntfs3/attrib.c

@@ -2114,9 +2114,11 @@ int attr_insert_range(struct ntfs_inode *ni, u64 vbo, u64 bytes)
 
 	if (!attr_b->non_res) {
 		data_size = le32_to_cpu(attr_b->res.data_size);
+		alloc_size = data_size;
 		mask = sbi->cluster_mask; /* cluster_size - 1 */
 	} else {
 		data_size = le64_to_cpu(attr_b->nres.data_size);
+		alloc_size = le64_to_cpu(attr_b->nres.alloc_size);
 		mask = (sbi->cluster_size << attr_b->nres.c_unit) - 1;
 	}
 
@@ -2130,6 +2132,13 @@ int attr_insert_range(struct ntfs_inode *ni, u64 vbo, u64 bytes)
 		return -EINVAL;
 	}
 
+	/*
+	 * valid_size <= data_size <= alloc_size
+	 * Check alloc_size for maximum possible.
+	 */
+	if (bytes > sbi->maxbytes_sparse - alloc_size)
+		return -EFBIG;
+
 	vcn = vbo >> sbi->cluster_bits;
 	len = bytes >> sbi->cluster_bits;
 

fs/ntfs3/file.c

@@ -733,9 +733,6 @@ static long ntfs_fallocate(struct file *file, int mode, loff_t vbo, loff_t len)
 	if (map_locked)
 		filemap_invalidate_unlock(mapping);
 
-	if (err == -EFBIG)
-		err = -ENOSPC;
-
 	if (!err) {
 		inode->i_ctime = inode->i_mtime = current_time(inode);
 		mark_inode_dirty(inode);