Failing extents tests

Hi,

The extents support in e2fsprogs-1.41.1 doesn't pass a few of the regression tests that we had created. 4 tests out of 20 are failing, I have included some details about the failures.

e2fsprogs-tests-f_extents_ee_len.patch: Corrupt ee_len is not detected. e2fsprogs-tests-f_extents_ei_block.patch: Corrupt ei_block is not detected. In the Sun extents code, we passed the previous extent to ext2fs_extent_verify(), so additional sanity checks could be performed. Here is a snippet of that:

/* Verify that a single extent @ex is valid. If @ex_prev is passed in,
* then this was the previous logical extent in this block and we can
* do additional sanity checking (though in case of error we don't know
* which of the two extents is bad). Similarly, if @ix is passed in
* we can check that this extent is logically part of the index that
* refers to it (though again we can't know which of the two is bad). */
errcode_t ext2fs_extent_verify(ext2_filsys fs, struct ext3_extent *ex,
struct ext3_extent *ex_prev, struct ext3_extent_idx *ix, int ix_len)

Similarly we also passed previous ext3_extent_idx to ext2fs_extent_index_verify().

Maybe we can do something similar by adding ex_prev and ix_prev to ext2_extent_handle_t?

e2fsprogs-tests-f_extents_imbalanced_tree.patch, e2fsprogs-tests-f_extents_eh_depth.patch: In both these cases, e2fsck aborts with a "Corrupt extent header on inode %i" error. Instead of aborting we can clear the extent header and set i_blocks to 0?

I have uploaded these tests at
http://downloads.lustre.org/public/tools/e2fsprogs/extent_tests/

One problem with these tests is that, the high 16 bits of extent/index block are set, so these tests cannot be used as-is, but the image should be helpful to check if the problem is solved or not.

Thanks,
Kalpak