[v5,0/2] Amiga RDB partition support fixes

Message

Michael Schmitz Oct. 12, 2018, 12:26 a.m. UTC

yet another new version of the Amiga RDB partition table patch. 
I've split off the part fixing the incorrect use of signed int    
for partition start address and size as separate patch. This change
should be incontroversial (I hope). It does fix the bug that Martin   
Steigerwald reported six years ago for a 2 TB disk. I have tested this
patch with the identical RDB partition data that Martin saw the bug with.
I have incorporated Andreas' feedback on proper use of casts to avoid
integer overflow in this version.

The simple fix still leaves ample room for overflows in calculating start
address and size of a RDB partition, though such overflows should only be
seen in rather unusual cases. To address these potential overflows, checks
are added in the second patch of this series.

The use of u64 instead of sector_t in the second patch is required to catch
overflows even in cases where sector_t is 32 bit wide (i.e. no LBD support).

Cheers,

	Michael

Comments

Martin Steigerwald Oct. 12, 2018, 8:17 a.m. UTC | #1

Michael Schmitz - 12.10.18, 02:26:
> yet another new version of the Amiga RDB partition table patch.
> I've split off the part fixing the incorrect use of signed int
> for partition start address and size as separate patch. This change
> should be incontroversial (I hope). It does fix the bug that Martin
> Steigerwald reported six years ago for a 2 TB disk. I have tested this
> patch with the identical RDB partition data that Martin saw the bug
> with. I have incorporated Andreas' feedback on proper use of casts to
> avoid integer overflow in this version.

Just as a note for all the AmigaOS users out there: Hyperion 
Entertainment released AmigaOS 3.1.4 for various Amiga models. This 
should fix all (known) issues with large disks for good directly in the 
Kickstart ROM instead of via SetPatch updating the ROM by replacing 
modules or by using NSDPatch approach. Olaf Barthel was one of the 
developers involved with the update. Digital downloads only so far, 
physical releases with floppy disks and ROM chips are announced.

This would be another reason to support large disks in Linux as well.

Thank you, Michael.

(Omitting link as to not too directly advertise proprietary products 
here, it is easy enough to find.)

Thanks,

John Paul Adrian Glaubitz Oct. 12, 2018, 8:41 a.m. UTC | #2

On 10/12/18 10:17 AM, Martin Steigerwald wrote:
> Just as a note for all the AmigaOS users out there: Hyperion
> Entertainment released AmigaOS 3.1.4 for various Amiga models. This
> should fix all (known) issues with large disks for good directly in the
> Kickstart ROM instead of via SetPatch updating the ROM by replacing
> modules or by using NSDPatch approach. Olaf Barthel was one of the
> developers involved with the update. Digital downloads only so far,
> physical releases with floppy disks and ROM chips are announced.


Thanks for the heads-up. It's 29,95 Euro per copy. I would actually buy
this, but since I would rather want to update all of my Amigas, this
would be pretty expensive.

I'm going to contact them and ask whether they have a discount.

Adrian