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    SubjectRe: [Q] FAT driver enhancement

    > A while ago I initiated a thread about mounting a NTFS partition as FAT
    > partition. The problem is that FAT partitions do not have a real
    > fingerprint, so the FAT driver mounts almost anything.
    > The current 2.5 driver only tests if some values in the bootsector are
    > non-zero. IMHO, this is not strict enough. For example, the number of FATs
    > is always 1 or 2 (anyone ever seen more ?). Besides, when there are two
    > FATs, all entries in those FATs should be equal. If they are not, we deal
    > with a non-FAT or broken FAT partition, and we should not mount.
    > It's not a real fingerprint, but what are the chances all sectors of what
    > we think is the FAT are equal on non-FAT filesystems ? Yes, when you just
    > did a
    > dd if=/dev/zero of=/dev/partition; mkfs.somefs /dev/partition
    > there is a chance, but that's an empty filesystem. Data corruption isn't
    > that bad on an empty disk. We know that a FAT is at the beginning of a
    > partition and I assume that any other filesystem will fill up those first
    > sectors very soon.
    > Questions:
    > 1) How do you think about the checking of the FAT tables ? It definitely
    > will slow down the mount.

    Reading FATs is very fast, and they are probably going to be needed,
    anyway. I guess its okay.

    > 2) If I implement it, where shoud it go ? At the moment, I hacked
    > fat_read_super, for there the FAT fs is validated, but I got the
    > feeling this is not the place to be.
    > 3) Anyone seen more than two FATs on a filesystem ? Can I assume there is
    > a limit ?

    No. I think you can only have two.

    (about SSSCA) "I don't say this lightly. However, I really think that the U.S.
    no longer is classifiable as a democracy, but rather as a plutocracy." --hpa
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