Re: [Lit.] Buffer overruns

From: Brian Inglis (Brian.Inglis_at_SystematicSW.Invalid)
Date: 02/01/05 

Date: Tue, 01 Feb 2005 15:02:10 GMT

On Tue, 1 Feb 2005 11:00:55 +0000 in alt.folklore.computers, Steve
O'Hara-Smith <steveo@eircom.net> wrote:

>On Tue, 1 Feb 2005 06:37:13 +0000 (UTC)
>infobahn <infobahn@btinternet.com> wrote:
>
>> David Wagner wrote:
>> >
>> > infobahn wrote:
>> > >I take overruns far /more/ seriously than many
>> > >of the security people who've discussed the matter here.
>> >
>> > I would have thought someone who really took buffer overruns seriously
>> > would strive to use both the most careful development methodology they
>> > could
>> > afford *and* ABC.
>>
>> Oh, be nice. :-)
>>
>> I've tried hard to understand how you could possibly need ABC in
>> production, and I have begun to realise that it /is/ necessary if
>> your programmers don't actually understand the C language in
>
> Adding ABC to C is *really* difficult. Any function that takes
>a pointer as an argument has no access to information on the bounds for
>manipulating that pointer, to make matters worse those bounds may be
>determined at run time (eg. in a malloc call) or at compile time and
>the function may live in a shared library. I won't say it's impossible
>to do ABC for C, but it's certainly not easy. To make ABC easy to implement
>you have to use a base and offset paradigm instead of a pointer paradigm.

base == pointer, offset == 0; any easier? 

-- 
Thanks. Take care, Brian Inglis 	Calgary, Alberta, Canada
Brian.Inglis@CSi.com 	(Brian[dot]Inglis{at}SystematicSW[dot]ab[dot]ca)
    fake address		use address above to reply

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