[PATCH] e2fsprogs: fix endian handling of ext3_extent_header

[PATCH] e2fsprogs: fix endian handling of ext3_extent_header

[Eric Sandeen]

This turned up when trying to resize a filesystem containing
a file with many extents on PPC64.

Fix all locations where ext3_extent_header members aren't
handled in an endian-safe manner.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
---

I only audited ext3_extent_header's members, and found places
where they were not properly endian-handled.

Is there a reason that disk structures aren't sparse-annotated
for endianness?  I can't help but wonder if there's a lot
more than this lurking.

diff --git a/lib/ext2fs/ext3_extents.h b/lib/ext2fs/ext3_extents.h
index 4163436..a18d705 100644
--- a/lib/ext2fs/ext3_extents.h
+++ b/lib/ext2fs/ext3_extents.h
@@ -106,15 +106,20 @@ struct ext3_ext_path {
 	((struct ext3_extent_idx *) (((char *) (__hdr__)) +	\
 				     sizeof(struct ext3_extent_header)))
 #define EXT_HAS_FREE_INDEX(__path__) \
-	((__path__)->p_hdr->eh_entries < (__path__)->p_hdr->eh_max)
+	(ext2fs_le16_to_cpu((__path__)->p_hdr->eh_entries) < \
+	 ext2fs_le16_to_cpu((__path__)->p_hdr->eh_max))
 #define EXT_LAST_EXTENT(__hdr__) \
-	(EXT_FIRST_EXTENT((__hdr__)) + (__hdr__)->eh_entries - 1)
+	(EXT_FIRST_EXTENT((__hdr__)) + \
+	ext2fs_le16_to_cpu((__hdr__)->eh_entries) - 1)
 #define EXT_LAST_INDEX(__hdr__) \
-	(EXT_FIRST_INDEX((__hdr__)) + (__hdr__)->eh_entries - 1)
+	(EXT_FIRST_INDEX((__hdr__)) + \
+	ext2fs_le16_to_cpu((__hdr__)->eh_entries) - 1)
 #define EXT_MAX_EXTENT(__hdr__) \
-	(EXT_FIRST_EXTENT((__hdr__)) + (__hdr__)->eh_max - 1)
+	(EXT_FIRST_EXTENT((__hdr__)) + \
+	ext2fs_le16_to_cpu((__hdr__)->eh_max) - 1)
 #define EXT_MAX_INDEX(__hdr__) \
-	(EXT_FIRST_INDEX((__hdr__)) + (__hdr__)->eh_max - 1)
+	(EXT_FIRST_INDEX((__hdr__)) + \
+	ext2fs_le16_to_cpu((__hdr__)->eh_max) - 1)
 
 #endif /* _LINUX_EXT3_EXTENTS */
 
diff --git a/lib/ext2fs/inline_data.c b/lib/ext2fs/inline_data.c
index 7eb8b94..8167b76 100644
--- a/lib/ext2fs/inline_data.c
+++ b/lib/ext2fs/inline_data.c
@@ -420,7 +420,7 @@ ext2fs_inline_data_file_expand(ext2_filsys fs, ext2_ino_t ino,
 		eh = (struct ext3_extent_header *) &inode->i_block[0];
 		eh->eh_depth = 0;
 		eh->eh_entries = 0;
-		eh->eh_magic = EXT3_EXT_MAGIC;
+		eh->eh_magic = ext2fs_cpu_to_le16(EXT3_EXT_MAGIC);
 		i = (sizeof(inode->i_block) - sizeof(*eh)) /
 			sizeof(struct ext3_extent);
 		eh->eh_max = ext2fs_cpu_to_le16(i);