在Linux系统下执行这段代码 :（）{ :|:& }；： 就会引起死机，一旦执行起来后，唯一的方法就是重启系统。实际上这段代码是一段无限递归代码，将系统资源耗尽。本文下面有这段代码的详细解释，为了防止fork炸弹，方法就是限制用户能够启动的进程数。具体做法，编辑/etc/security/limits.conf文件，在末尾加入 ： * hard nproc 200 将用户的进程数限制为200，经过测试，root账户不受这个限制。Q. Can you explain following bash code or bash fork（） bomb？ :（）{ :|:& };:A. This is a bash function. It gets called recursively （recursive function）. This is most horrible code for any Unix / Linux box. It is often used by sys admin to test user processes limitations （Linux process limits can be configured via /etc/security/limits.conf and PAM）.Once a successful fork bomb has been activated in a system it may not be possible to resume normal operation without rebooting, as the only solution to a fork bomb is to destroy all instances of it.WARNING！ These examples may crash your computer if executed.
Understanding :（）{ :|:& };: fork（） bomb code
:（） - It is a function name. It accepts no arguments at all. Generally, bash function is defined as follows:foo（）{ arg1=$1 echo "" #do_something on $arg argument}fork（） bomb is defined as follows::（）{ :|:&};::|: - Next it call itself using programming technique called recursion and pipes the output to another call of the function ":". The worst part is function get called two times to bomb your system.& - Puts the function call in the background so child cannot die at all and start eating system resources.; - Terminate the function definition: - Call （run） the function aka set the fork（） bomb.Here is more human readable code:bomb（） { bomb | bomb &}; bombProperly configured Linux / UNIX box should not go down when fork（） bomb sets off. Linux Kernel “fs/partitions/ldm.c”缓冲区溢出和拒绝服务漏洞Cisco TelePresence多个产品缓冲区溢出漏洞相关资讯 Linux安全
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