Bug#578046: currupts archives on 64bit systems with buffers larger than 2gb

[Koen Holtman <k.holtman@chello.nl>]

[removed some general mailing lists from cc:]

Overall, I have concluded that correct support for >=2GB afio memory 
buffers on 32 bit or 64 bit systems opens up a too-large can of testing 
worms, especially as size_t and int are still 32 bits even on amd64.

So I have resolved this (in my upstream development copy) by making afio 
reject attempts to use buffers larger than 1.5GB.  See the HISTORY file in 
the upstream repository https://github.com/kholtman/afio for the full 
details.  At least this way there is low risk that afio will silently 
fail.

Cheers,

Koen.

On Mon, 27 Feb 2012, Koen Holtman wrote:

> On Fri, 16 Apr 2010, Yuri D'Elia wrote:
>
> > Package: afio
> > Severity: important
> > Tags: patch
> >
> > When the block size * block count equals to 2gb or more, afio corrupts the
> > archive by truncating all files larger than 2gb.
> [...]
>
> Thanks for the bug report and patch, I am reviewing and incorporating it in 
> the upstream.
>
> The patch upgrades some uints to size_t, but it does not upgrade the count 
> argument of readall to size_t, so I think this might lead to the achive 
> ending up corrupt because not all data is written into it if your memory 
> buffer (size * block count) is over 4GB and the file being archived is over 4 
> GB. I am not entirely sure, I have not tested it to verify, but just a 
> warning: if you upgraded to 4GB memory buffer you might have gotten corrupt 
> archives.
>
> Cheers,
>
> Koen.