[PATCH 12/13] dlfcn,elf: implement dlmem() [BZ #11767]

[Adhemerval Zanella Netto]

On 29/03/23 11:20, stsp via Libc-alpha wrote:
> 
> 29.03.2023 19:10, Jonathon Anderson пишет:
>> Stas,
>>
>> Please do some research into the ELF file format. Neither your fdlopen implementation in the test cases nor your dlopen_with_offset implementation in the email chain implement it correctly.
>>
>> AFAICT, the first glaring issue with both of your implementations is that you have neglected the case where p_offset != p_vaddr, i.e. a segment is mmapped to a different location than its layout in the file. There are a LOT of binaries out in the wild where this is the case. Here's a quick one-liner to help you find some on your own box, I have 11712 such binaries on my Debian system:
> 
> Sure as hell p_offset != p_vaddr.
> I never ever assumed it does!
> OK, if it goes that badly, then I offer you
> a deal.
> If you present the solib with p_offset!=p_vaddr
> and demonstrate that its broken with dlmem(),
> and not because some random bug of mine but
> exactly because p_offset!=p_vaddr, then I go
> away from that dlmem() proposal forever.
> If you can't, then you go away.
> Do you accept that challenge?
> Sorry for offering the silly stuff, but I simply
> don't see how to proceed if we are wasting
> the time on a things like that.
> 

This should be other way around since you are the one proposing a new
interface and thus should make sure that potential raised concerns 
indeed does not affect it. 

Also, I would like to ask to tune down your tone. This kind of aggressive
way to present technical topics, in a manner of adding 'challengers' to
put pressure on person that raised concerns is not best way and usually
make other developers to avoid engage further in the topic.