DrvFs reports incorrect file block sizes

[DHowett-MSFT]

du is reporting wildly unusual file sizes on DrvFs.

# PWD = /mnt/c/Users/duhowett/Desktop
$ du --apparent-size file
8784 file
$ du --block-size=1 file
6291968 file

When du is used without --apparent-size, it should be returning the number of filesystem blocks consumed by file, converted into bytes. This reports that file is 6.2MiB where on disk it is truly 8KiB.

If we look at stat we see that the number of "512B blocks" is reported to match the number of bytes the file consumes according to Explorer.

$ stat file
  File: file
  Size: 8784            Blocks: 12289

Excerpt from man 2 stat

blkcnt_t  st_blocks;      /* Number of 512B blocks allocated */

DrvFs reports the number of bytes occupied by the file on-disk as the number of 512B blocks the file occupies on disk, which makes disk usage tools such as du report vastly incorrect file sizes.

[0xbadfca11]

Maybe same problem as #1894

[stehufntdev]

Yes this looks like the same issue as #1894 to me as well. Adding @SvenGroot to double check as he was looking into the fix.

[SvenGroot]

Yes, that's the same problem, and it has been fixed internally. It'll be in a future insider build.