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Re: Stackoverflow, and how C uses stack to remember function calls

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On Sat, 4 Mar 2017 14:40:48 +0300, Alla <vitale.alla@gmail.com> wrote:

>Below is an example a completely incorrect code that doesn't perform any 
>error checking, and used for illustration purpose. This program will 
>"blindly" copy one string into another. If the length of bar exceeds the 
>length of c, then something longer than allocated memory on stack will 
>creep into c's return address space (almost quoting), and worse yet
>(here starts the part I would like your help on) as C language secretly 
>uses stack also to remember when the function is called and what is the 
>address of the previous function called, a "bad guy" can "jump back" to 

Be aware that while this may be a common approach, it is still very
system specific, both hardware and software.  My system does not have
a hardware stack though it does store local variables in a similar
manner.  Return addresses are passed to the called function in a
register, not in memory, and therefore cannot be corrupted this way.
Furthermore, the "stacks" used to store the local variables of
different functions need not be contiguous; it looks more like a
linked list than a typical hardware stack.

Unless you intend to write a compiler (or a piece of malware)  or need
to debug the memory dump produced when a large program fails, the
exact details of how this is done are clutter that serves only to
obscure the important details most new programmers need to absorb.
Curiosity is a virtue but not when it kills the cat.

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Stackoverflow, and how C uses stack to remember function calls Alla <vitale.alla@gmail.com> - 2017-03-04 14:40 +0300
  Re: Stackoverflow, and how C uses stack to remember function calls Malcolm McLean <malcolm.mclean5@btinternet.com> - 2017-03-04 03:53 -0800
    Re: Stackoverflow, and how C uses stack to remember function calls Alla <vitale.alla@gmail.com> - 2017-03-04 14:58 +0300
      Re: Stackoverflow, and how C uses stack to remember function calls Malcolm McLean <malcolm.mclean5@btinternet.com> - 2017-03-04 04:04 -0800
        Re: Stackoverflow, and how C uses stack to remember function calls Alla <vitale.alla@gmail.com> - 2017-03-04 15:12 +0300
    Re: Stackoverflow, and how C uses stack to remember function calls mark.bluemel@gmail.com - 2017-03-06 00:41 -0800
  Re: Stackoverflow, and how C uses stack to remember function calls David Brown <david.brown@hesbynett.no> - 2017-03-04 13:30 +0100
    Re: Stackoverflow, and how C uses stack to remember function calls Alla <vitale.alla@gmail.com> - 2017-03-04 15:34 +0300
      Re: Stackoverflow, and how C uses stack to remember function calls David Brown <david.brown@hesbynett.no> - 2017-03-04 15:23 +0100
        Re: Stackoverflow, and how C uses stack to remember function calls Alla <vitale.alla@gmail.com> - 2017-03-04 18:22 +0300
          Re: Stackoverflow, and how C uses stack to remember function calls Chad <cdalten@gmail.com> - 2017-03-04 07:53 -0800
        Re: Stackoverflow, and how C uses stack to remember function calls Alla <vitale.alla@gmail.com> - 2017-03-04 19:29 +0300
  Re: Stackoverflow, and how C uses stack to remember function calls "James R. Kuyper" <jameskuyper@verizon.net> - 2017-03-04 11:18 -0500
    Re: Stackoverflow, and how C uses stack to remember function calls Alla <vitale.alla@gmail.com> - 2017-03-04 20:10 +0300
      Re: Stackoverflow, and how C uses stack to remember function calls "James R. Kuyper" <jameskuyper@verizon.net> - 2017-03-04 13:18 -0500
        Re: Stackoverflow, and how C uses stack to remember function calls Alla <vitale.alla@gmail.com> - 2017-03-04 22:43 +0300
    Re: Stackoverflow, and how C uses stack to remember function calls supercat@casperkitty.com - 2017-03-04 14:33 -0800
      Re: Stackoverflow, and how C uses stack to remember function calls Ian Collins <ian-news@hotmail.com> - 2017-03-05 11:50 +1300
        Re: Stackoverflow, and how C uses stack to remember function calls supercat@casperkitty.com - 2017-03-05 11:12 -0800
          Re: Stackoverflow, and how C uses stack to remember function calls Ian Collins <ian-news@hotmail.com> - 2017-03-06 17:11 +1300
            Re: Stackoverflow, and how C uses stack to remember function calls supercat@casperkitty.com - 2017-03-06 07:23 -0800
              Re: Stackoverflow, and how C uses stack to remember function calls David Brown <david.brown@hesbynett.no> - 2017-03-06 17:22 +0100
                Re: Stackoverflow, and how C uses stack to remember function calls scott@slp53.sl.home (Scott Lurndal) - 2017-03-06 16:40 +0000
                Re: Stackoverflow, and how C uses stack to remember function calls jm.bourguet@gmail.com - 2017-03-06 09:04 -0800
                Re: Stackoverflow, and how C uses stack to remember function calls scott@slp53.sl.home (Scott Lurndal) - 2017-03-06 17:18 +0000
                Re: Stackoverflow, and how C uses stack to remember function calls Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2017-03-06 11:22 -0700
                Re: Stackoverflow, and how C uses stack to remember function calls luser droog <luser.droog@gmail.com> - 2017-03-06 09:58 -0800
                Re: Stackoverflow, and how C uses stack to remember function calls luser droog <luser.droog@gmail.com> - 2017-03-06 10:04 -0800
  Re: Stackoverflow, and how C uses stack to remember function calls Barry Schwarz <schwarzb@dqel.com> - 2017-03-04 09:33 -0800
    Re: Stackoverflow, and how C uses stack to remember function calls Alla <vitale.alla@gmail.com> - 2017-03-04 22:46 +0300
  Re: Stackoverflow, and how C uses stack to remember function calls Keith Thompson <kst-u@mib.org> - 2017-03-04 12:25 -0800

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