在coursera上有个csapp有关的公开课 The Hardware/Software Interface
上面的lib2和csapp上的二进制炸弹实验一样,但是是64位的=.=,于是我还是去 http://csapp.cs.cmu.edu/public/labs.html上下载了一个32位的文件来练习.
下面是第一关的反汇编 

Dump of assembler code for function phase_1:
   0x08048b20 <+0>:   push   %ebp
   0x08048b21 <+1>:   mov    %esp,%ebp
   0x08048b23 <+3>:   sub    $0x8,%esp
   0x08048b26 <+6>:   mov    0x8(%ebp),%eax
   0x08048b29 <+9>:   add    $0xfffffff8,%esp
   0x08048b2c <+12>:  push   $0x80497c0   #从下面的strings_not_equal看出,这里是将正确字符串压栈
   0x08048b31 <+17>:  push   %eax
   0x08048b32 <+18>:  call   0x8049030 <strings_not_equal>
   0x08048b37 <+23>:  add    $0x10,%esp
   0x08048b3a <+26>:  test   %eax,%eax
   0x08048b3c <+28>:  je     0x8048b43 <phase_1+35>
   0x08048b3e <+30>:  call   0x80494fc <explode_bomb>
   0x08048b43 <+35>:  mov    %ebp,%esp
   0x08048b45 <+37>:  pop    %ebp
   0x08048b46 <+38>:  ret    
End of assembler dump.
 

所以 x/s 0x80497c0 即可以得到正确的答案

0x80497c0:"Public speaking is very easy."