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Background: I have two CentOS7 servers. Test & Prod.
There is a script myfilename.sh in my website, which is executed in php by shell_exec.
Script and all parent folders in both servers have identical selinux context. httpd_sys_rw_content_t

Problem statement: Script runs fine in Test server but doesn't work on Prod.
Audit log on Prod says SELinux is preventing /usr/bin/bash from execute access on the file myfilename.sh., but nothing shows up in Test box.

Any idea what could have possibly gone wrong and why the script is working on Test box. I need to reproduce the issue on Test server before fixing it on prod.

Here is the audit log:

SELinux is preventing /usr/bin/bash from execute access on the file myfilename.sh.

*****  Plugin catchall (100. confidence) suggests   **************************

If you believe that bash should be allowed execute access on the myfilename.sh file by default.
Then you should report this as a bug.
You can generate a local policy module to allow this access.
Do
allow this access for now by executing:
# ausearch -c 'sh' --raw | audit2allow -M my-sh
# semodule -i my-sh.pp


Additional Information:
Source Context                system_u:system_r:httpd_sys_script_t:s0
Target Context                unconfined_u:object_r:httpd_sys_rw_content_t:s0
Target Objects                myfilename.sh [ file ]
Source                        sh
Source Path                   /usr/bin/bash
Port                          <Unknown>
Host                          <Unknown>
Source RPM Packages           bash-4.2.46-21.el7_3.x86_64
Target RPM Packages           
Policy RPM                    selinux-policy-3.13.1-102.el7_3.16.noarch
Selinux Enabled               True
Policy Type                   targeted
Enforcing Mode                Enforcing
Host Name                     ip-X-X-X-X
Platform                      Linux ip-X-X-X-X 3.10.0-327.10.1.el7.x86_64
                              #1 SMP Tue Feb 16 17:03:50 UTC 2016 x86_64 x86_64
Alert Count                   23
First Seen                    2017-06-17 06:33:36 CDT
Last Seen                     2017-06-18 02:18:01 CDT
Local ID                      340158ca-61f6-4472-aadb-18a3bbc34a22

Raw Audit Messages
type=AVC msg=audit(1497770281.465:12508): avc:  denied  { execute } for  pid=10042 comm="sh" name="myfilename.sh" dev="xvdc" ino=3416830 scontext=system_u:system_r:httpd_sys_script_t:s0 tcontext=unconfined_u:object_r:httpd_sys_rw_content_t:s0 tclass=file


type=SYSCALL msg=audit(1497770281.465:12508): arch=x86_64 syscall=execve success=no exit=EACCES a0=20d5650 a1=20d5730 a2=20d3c20 a3=7ffe9f4d7de0 items=0 ppid=10041 pid=10042 auid=4294967295 uid=995 gid=992 euid=995 suid=995 fsuid=995 egid=992 sgid=992 fsgid=992 tty=(none) ses=4294967295 comm=sh exe=/usr/bin/bash subj=system_u:system_r:httpd_sys_script_t:s0 key=(null)

Hash: sh,httpd_sys_script_t,httpd_sys_rw_content_t,file,execute
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httpd_sys_rw_content_t context will not work for executables. We need to set httpd_sys_script_exec_t context for that

sudo semanage fcontext -a -t httpd_sys_script_exec_t  "/PATH_TO_FILE/myfilename.sh"

And then don't forget to run restorecon.

sudo restorecon -Rv /PATH_TO_FILE/

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