Hi David,
On 17/07/23 20:00, David Laight wrote:
From: Michael Schmitz
Sent: 16 July 2023 00:27
The Amiga partition parser module uses signed int for partition sector
address and count, which will overflow for disks larger than 1 TB.
Use u64 as type for sector address and size to allow using disks up to
2 TB without LBD support, and disks larger than 2 TB with LBD. The RBD
format allows to specify disk sizes up to 2^128 bytes (though native
OS limitations reduce this somewhat, to max 2^68 bytes),
Pretty much everything (including the mass of an proton) stops
you having a disk with anywhere near 2^64 bytes in it.
I put my hopes on all that dark matter we still seem to be missing then.
Seriously though - RDB allows for this size, no matter how unlikely.
2^32 heads or 2^32 sectors per track would have been seen as impossible
when RDB was designed. On the other hand, the '16 bit address space
ought to be enough for everybody' was probably still fresh in the mind
of the Amiga developers at that time.
All that matters is that we get the size calculations right (and then
let the partition core enforce the known disk size limit).
Cheers,
Michael
David
so check for
u64 overflow carefully to protect against overflowing sector_t.
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