今天是来到陌生城市的第66天,隔离起来的第52天,距离原定的复工日期已经18天。
总算等到重回正轨的好消息了。
国外的情况还是很严峻啊,祝福国外的朋友平安顺利。
This time is a challenge from last week’s CTF game organized by XCTF with many Chinese universities. This chanllenge is a linux kernel exploitation designed by SixStar Team. I didn’t finished it during the game, most of the time I spent on searching for objects to refill the size 0x20-0x70
, only at very last moment I realize there was a freelist harderned in the kernel. Many teams solved it by unexpected solution because of the deployment mistake, which is unpleasant, but it is still a good challenge.
I learned the solution from Kernoob: kmalloc without SMAP, thanks Kirin! Based on his writeup, I will make some notes about the debugging and details of the bypass.