HW4

part one

fuzzer

part two

part two A

gdb p2 -q
disass main
disass check_answer

break *0x08048549
run 11111111111111111
i r esp
x/72xw $esp
x/s ans_buf
x/s &ans_flag

objdump -xtrds

p1 not problem due to the call of strlen, find from GDB

p2

check 
stackoverflow vulnerability, 48*1 + {exit_code} will exit the program directly

when you compile in gdb, the ASLR is off.

p3

stackoverflow protection in compile time 
*** stack smashing detected ***: ./so terminated
Aborted (core dumped)