From U-Boot commit:

| commit b5bbac1
| Author: Ionut Nicu <ioan.nicu.ext@nsn.com>
| Date:   Mon Jan 13 12:00:08 2014 +0100
|
|     ext4fs: fix "invalid extent block" error
|
|     For files where we actually have extent indexes following
|     an extent header (ext_block->eh_depth != 0), the do/while
|     loop from ext4fs_get_extent_block() does not select the
|     proper extent index structure.
|
|     For example, if we have:
|
|     ext_block->eh_depth = 1
|     ext_block->eh_entries = 1
|     fileblock = 0
|     index[0].ei_block = 0
|
|     the do/while loop will exit with i set to 0 and the
|     ext4fs_get_extent_block() function will return 0, even if
|     there was a valid extent index structure following the
|     header.
|
|     Signed-off-by: Ionut Nicu <ioan.nicu.ext@nsn.com>
|     Signed-off-by: Mathias Rulf <mathias.rulf@nsn.com>

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>