Getting a Seg Fault

[adam2016]

Hey guys,

I seem to be getting a seg fault from a short rudimentary C program, the program just contains a char buffer (500 bytes) the string passed in from args is copied to buffer

But I seem to be getting a segfault even though I only fill my buffer up with 500 bytes,

  #include <stdio.h>
  #include <string.h>

  int main(int argc,char** argv){

    char buffer[500];
    strcpy(buffer,argv[1]);
    return 0;
  }

I used gcc -g -m32 -fno-stack-protector vuln.c -o vuln

to compile the program

and ./sample $(python -c 'print "\x41" * 500')
to run the application with 500 'A's

but I receive a seg fault,

I'm using Kali Linux if that is of any importance.

thanks

[Ganado]

strcpy also copies the null terminator.
Does your code crash if you do "A" * 499?

[adam2016]

ahh good point, I didn't even think of that as a possibility,

seems to work fine with 499 :) , only crashes at 500

Thanks