SELinux Is Preventing /usr/libexec/postfix/pickup From module_request

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Getting module_request errors from SELinux. Errors being thrown by

metacity
sendmail.postfix
cleanup
trivial-rewarite
local
postdrop
pickup

 

All errors are essentially the same

System was working well until I began to apply some basic security hardening configuration.

Postfix started complaining when I made /tmp noexec, nodev, nosuid, and then did a

mount --bind

of /var/tmp under /tmp.

Backed that out the remount of /var/tmp and those errors went away. But then these errors started showing up.

Here is an example of a postfix pickup error. What is going on? I could allow the module to load, but I want to understand what is going on and the dangers of making the mod before I do it.

SELinux is preventing /usr/libexec/postfix/pickup from module_request access on the system Unknown.

***** Plugin catchall_boolean (89.3 confidence) suggests *******************

If you want to allow all domains to have the kernel load modules Then you must tell SELinux about this by enabling the 'domain_kernel_load_modules' boolean. Do setsebool -P domain_kernel_load_modules 1

***** Plugin catchall (11.6 confidence) suggests ***************************

If you believe that pickup should be allowed module_request access on the Unknown system 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 pickup /var/log/audit/audit.log | audit2allow -M mypol
# semodule -i mypol.pp

Additional Information:
Source Context system_u:system_r:postfix_pickup_t:s0
Target Context system_u:system_r:kernel_t:s0
Target Objects Unknown [ system ]
Source pickup
Source Path /usr/libexec/postfix/pickup
Port
Host desk.localdomain
Source RPM Packages postfix-2.6.6-2.2.el6_1
Target RPM Packages
Policy RPM selinux-policy-3.7.19-126.el6_2.10
Selinux Enabled True
Policy Type targeted
Enforcing Mode Enforcing
Host Name desk.localdomain
Platform Linux desk.localdomain
2.6.32-220.13.1.el6.x86_64
#1 SMP Tue Apr 17 23:56:34 BST 2012 x86_64
x86_64
Alert Count 24
First Seen Fri 27 Apr 2012 02:46:55 PM MDT
Last Seen Sun 29 Apr 2012 05:10:32 AM MDT
Local ID 4b8e5292-93f1-4e69-8bb4-4ea70bc5232e

Raw Audit Messages
type=AVC msg=audit(1335697832.612:34911): avc: denied
{ module_request } for pid=24226 comm="pickup" kmod="net-pf-10"
scontext=system_u:system_r:postfix_pickup_t:s0
tcontext=system_u:system_r:kernel_t:s0 tclass=system

type=SYSCALL msg=audit(1335697832.612:34911): arch=x86_64 syscall=socket
success=no exit=EAFNOSUPPORT a0=a a1=1 a2=0 a3=7fff3ca82190 items=0
ppid=1925 pid=24226 auid=4294967295 uid=0 gid=0 euid=0 suid=0 fsuid=0
egid=0 sgid=0 fsgid=0 tty=(none) ses=4294967295 comm=pickup
exe=/usr/libexec/postfix/pickup
subj=system_u:system_r:postfix_pickup_t:s0 key=(null)

Hash: pickup,postfix_pickup_t,kernel_t,system,module_request

audit2allow

#============= postfix_pickup_t ==============
#!!!! This avc can be allowed using the boolean 'domain_kernel_load_modules'

allow postfix_pickup_t kernel_t:system module_request;

audit2allow -R

#============= postfix_pickup_t ==============
#!!!! This avc can be allowed using the boolean 'domain_kernel_load_modules'

allow postfix_pickup_t kernel_t:system module_request;

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