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Date: Tue, 22 Jan 2013 17:11:42 +0100
From: Szabolcs Nagy <nsz@...t70.net>
To: musl@...ts.openwall.com, pierre@...entlife.com
Subject: Re: dladdr()

* pierre <pierre@...entlife.com> [2013-01-22 15:59:46 +0100]:
> > in the event the stack has been smashed,
> > following the stack frames is likely 
> > (almost certain) to lead you to [bad] 
> > destinations [...] that might not even 
> > be valid
> 
> That's precisely what I wrote in that email
> that nobody seems to have read.
> 

i can assure you that at least i read your mail

we know that you think that the stack is smashed
but you found it important to mention that in debug
mode it works while it crashes in release mode
(whatever those modes mean)

what you do is suspicious because if you get the
backtrace in a running program then it's most
likely invalid
(and i thought we could help you before you spend
too much time on inherently invalid design and
even give an explanation why it worked in debug
mode)

i dont think anyone tried to argue with you
or offend you in any way

> And I added, just in case it could help, that 
> dladdr should not crash when trying to lookup
> invalid addresses.

addr is never dereferenced in musl's code
so invalid addr is not an issue

> > there won't be frame pointers to help you 
> > follow the stack frames out of libc functions
> 
> For mere mortals, knowing that it's in libc
> is enough, as they then will check what junk
> was given to libc (and then will write a 
> workaround if they feel that libc is buggy).
> 
> For those with a stronger motivation, helping
> to strengthen a decent libc makes a lot more
> sense.
> 
> I have no other motivation when I invest some 
> of my time here.

i honestly dont understand what you are trying
to say

but i'm glad that you found musl useful whatever
you are doing

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