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I'm trying to overwrite a return address by using buffer overflow.

  1 #include <stdio.h>
  2 #include <string.h>
  3 
  4 void jumphere(){
  5     printf("SUCCESS!!");
  6 }
  7 
  8 int main(int argc, char** argv){
  9     char buffer [8];
 10     strcpy(buffer, argv[1]);
 11 
 12     printf("%s\n", buffer);
 13 
 14     return 0;
 15 }

I found that the return address is 0x00007ffff7a05b97

(When the main function ends, the last address that $rip points is 0x00007ffff7a05b97)

and the address of a function that I want to jump to is 0x0000000000400577.

So, I filled the buffer with As and gave an additional input of +"\x77\x05\x40\x00\x00\x00".

The return address is overwritten, but it became 0x00007fff00400577.

It seems that additional "\x00"s are ignored because \x00 is a NUL byte.

But that return address doesn't jump to the function that I want.

How can I overwrite the return address that has "\x00"s?

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