udf: Fix bitmap overflow on large filesystems with small block size
For large UDF filesystems with 512-byte blocks the number of necessary
bitmap blocks is larger than 2^16 so s_nr_groups in udf_bitmap overflows
(the number will overflow for filesystems larger than 128 GB with
512-byte blocks). That results in ENOSPC errors despite the filesystem
has plenty of free space.
Fix the problem by changing s_nr_groups' type to 'int'. That is enough
even for filesystems 2^32 blocks (UDF maximum) and 512-byte blocksize.
Reported-and-tested-by: v10lator@myway.de
Signed-off-by: Jan Kara <jack@suse.cz>
diff --git a/fs/udf/udf_sb.h b/fs/udf/udf_sb.h
index 5f02722..8d1c9d4 100644
--- a/fs/udf/udf_sb.h
+++ b/fs/udf/udf_sb.h
@@ -82,7 +82,7 @@
struct udf_bitmap {
__u32 s_extLength;
__u32 s_extPosition;
- __u16 s_nr_groups;
+ int s_nr_groups;
struct buffer_head **s_block_bitmap;
};