F18, selinux & sensors

[Cristian Sava]

Hi all,

I want to monitor hardware temperatures using sensors.
sensors is working ok lunched in a terminal but i want to display the
output on the web.
So i have this simple php:

<?php
echo exec('/var/www/cgi-bin/my_sensors.sh');
?>

and my_sensors.sh in cgi-bin:

#!/usr/bin/bash
/usr/bin/sensors
exit

Why the problem showed in /var/log/messages (and blank web page)?
sensors is supposed to run ok, is it?
my_sensors lunch sensors = OK
sensors try i2c-adapter = deny
Do i miss something?

setroubleshoot: SELinux is preventing /usr/bin/sensors from read access
on the directory i2c-adapter. For complete SELinux messages. run sealert
-l 94ef69e6-5109-4c22-b464-ef220948dd6a

[root at s194 cgi-bin]# sealert -l 94ef69e6-5109-4c22-b464-ef220948dd6a
SELinux is preventing /usr/bin/sensors from read access on the directory
i2c-adapter.

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

If you believe that sensors should be allowed read access on the
i2c-adapter directory 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:
# grep sensors /var/log/audit/audit.log | audit2allow -M mypol
# semodule -i mypol.pp


Additional Information:
Source Context                system_u:system_r:httpd_sys_script_t:s0
Target Context                system_u:object_r:sysfs_t:s0
Target Objects                i2c-adapter [ dir ]
Source                        sensors
Source Path                   /usr/bin/sensors
Port                          <Unknown>
Host                          s194.central.ucv.ro
Source RPM Packages           lm_sensors-3.3.2-5.fc18.x86_64
Target RPM Packages           
Policy RPM                    selinux-policy-3.11.1-87.fc18.noarch
Selinux Enabled               True
Policy Type                   targeted
Enforcing Mode                Enforcing
Host Name                     s194.central.ucv.ro
Platform                      Linux s194.central.ucv.ro
3.8.6-203.fc18.x86_64 #1
                              SMP Tue Apr 9 19:33:01 UTC 2013 x86_64
x86_64
Alert Count                   2
First Seen                    2013-04-12 15:59:12 EEST
Last Seen                     2013-04-12 15:59:13 EEST
Local ID                      94ef69e6-5109-4c22-b464-ef220948dd6a

Raw Audit Messages
type=AVC msg=audit(1365771553.642:434): avc:  denied  { read } for
pid=5314 comm="sensors" name="i2c-adapter" dev="sysfs" ino=15234
scontext=system_u:system_r:httpd_sys_script_t:s0
tcontext=system_u:object_r:sysfs_t:s0 tclass=dir


type=SYSCALL msg=audit(1365771553.642:434): arch=x86_64 syscall=openat
success=no exit=EACCES a0=ffffffffffffff9c a1=7fff2e427650 a2=90800 a3=0
items=0 ppid=5313 pid=5314 auid=4294967295 uid=48 gid=48 euid=48 suid=48
fsuid=48 egid=48 sgid=48 fsgid=48 ses=4294967295 tty=(none) comm=sensors
exe=/usr/bin/sensors subj=system_u:system_r:httpd_sys_script_t:s0
key=(null)

Hash: sensors,httpd_sys_script_t,sysfs_t,dir,read

audit2allow

#============= httpd_sys_script_t ==============
allow httpd_sys_script_t sysfs_t:dir read;

audit2allow -R
require {
	type httpd_sys_script_t;
}

#============= httpd_sys_script_t ==============
dev_list_sysfs(httpd_sys_script_t)


[root at s194 cgi-bin]#

C. Sava