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.

---
 fs/ext4/ext4_common.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

index 37b6c46..e543478 100644
@@ -1430,7 +1430,7 @@ static struct ext4_extent_header *ext4fs_get_extent_block
 			i++;
 			if (i >= le16_to_cpu(ext_block->eh_entries))
 				break;
-		} while (fileblock > le32_to_cpu(index[i].ei_block));
+		} while (fileblock >= le32_to_cpu(index[i].ei_block));
 
 		if (--i < 0)
 			return 0;

1.7.1

Applied to u-boot/master, thanks!

Tom
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