解决cannot enable executable stack as shared object requires: Permission denied问题

朱雀 2021-04-12 15:11 737阅读 1赞

启动错误问题排查

1、启动apache服务错误提示。

Starting httpd: httpd: Syntax error on line 211 of /etc/httpd/conf/httpd.conf: Syntax error on line 6 of /etc/httpd/conf.d/php.conf: Cannot 
    load /etc/httpd/modules/libphp5.so into server: libcrypto.so.6: cannot enable executable stack as shared object requires: Permission denied
    
    
    Starting httpd: httpd: Syntax error on line 211 of /etc/httpd/conf/httpd.conf: Syntax error on line 6 of /etc/httpd/conf.d/php.conf: Cannot 
    load /etc/httpd/modules/libphp5.so into server: libcrypto.so.6: cannot enable executable stack as shared object requires: Permission denied

通过以上错误判断应为selinux问题。

2、尝试关闭selinux，启动apache。

/usr/sbin/setenforce 0
    /etc/init.d/httpd start
    Starting httpd: [Wed Apr 24 12:37:39 2019]     [  OK  ]

启动成功了。确定是selinux问题。为系统安全，不想关闭selinux改如何解决呢？

解决selinux问题：

1、查看audit.log日志。

/usr/sbin/setenforce 1
    less /var/logs/audit/audit.log
    
    type=AVC msg=audit(1556086804.050:571845): avc:  denied  { execstack } for  pid=17397 comm="httpd" scontext=root:system_r:httpd_t:s0 tcontex
    t=root:system_r:httpd_t:s0 tclass=processtype=SYSCALL msg=audit(1556086804.050:571845): arch=c000003e syscall=10 success=no exit=-13 a0=7fff31feb000 a1=1000 a2=1000007 a3=4 items=0 
    ppid=17394 pid=17397 auid=0 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=pts1 ses=187 comm="httpd" exe="/usr/sbin/httpd" subj=root:system_r:httpd_t:s0 key=(null)

2、执行execstack处理。

最简单的解决办法就是执行execstack:
    execstack --clear-execstack /lib/libcrypto.so.6
    execstack --clear-execstack /lib/libcrypto.so.6
    
    execstack 部分参数如下：
    -s --set-execstack
                  Mark binary or shared library as requiring executable stack.
    -c --clear-execstack
                  Mark binary or shared library as not requiring executable stack.
    -q --query
                  Query executable stack marking of binaries and shared libraries.  For each file it prints either - when executable stack
                  is  not  required,  X  when executable stack is required or ?  when it is unknown whether the object requires or doesn’t
                  require executable stack (the marking is missing).
    
    通过-q参数查看指定文件是否需要executable stack，如果输出的开头是"-"，表示executable stack is  not  required，如果是“X”，表示executable stack is required，如果是“？”，表示未知。
    :/root> execstack -q /lib/libcrypto.so.6
    ? /lib/libcrypto.so.6
    :/root> execstack -c /lib/libcrypto.so.6
    :/root> execstack -q /lib/libcrypto.so.6
    - /lib/libcrypto.so.6
    :/root>

3、根据日志生成PP文件。

grep httpd /var/log/audit/audit.log | audit2allow -M httpdfixlocal
    
    ******************** IMPORTANT ***********************
    To make this policy package active, execute:
    
    semodule -i httpdfixlocal.pp

4、执行PP文件。

/usr/sbin/semodule -i httpdfixlocal.pp

5、启动httpd，可正常启动。

注意：setsebool，semodule等命令需安装如下工具包。
````
yum install policycoreutils
````