Description of problem:
SELinux is preventing /usr/sbin/useradd from 'write' accesses on the file /dev/null.

*****  Plugin leaks (86.2 confidence) suggests   *****************************

If you want to ignore useradd trying to write access the null file, because you believe it should not need this access.
Then you should report this as a bug.  
You can generate a local policy module to dontaudit this access.
Do
# grep /usr/sbin/useradd /var/log/audit/audit.log | audit2allow -D -M mypol
# semodule -i mypol.pp

*****  Plugin catchall (14.7 confidence) suggests   **************************

If you believe that useradd should be allowed write access on the null 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:
# grep useradd /var/log/audit/audit.log | audit2allow -M mypol
# semodule -i mypol.pp

Additional Information:
Source Context                unconfined_u:unconfined_r:useradd_t:s0-s0:c0.c1023
Target Context                unconfined_u:object_r:device_t:s0
Target Objects                /dev/null [ file ]
Source                        useradd
Source Path                   /usr/sbin/useradd
Port                          <Unknown>
Host                          (removed)
Source RPM Packages           shadow-utils-4.1.5.1-8.fc20.x86_64
Target RPM Packages           
Policy RPM                    selinux-policy-3.12.1-75.fc20.noarch
Selinux Enabled               True
Policy Type                   targeted
Enforcing Mode                Permissive
Host Name                     (removed)
Platform                      Linux (removed) 3.11.0-3.fc20.x86_64 #1 SMP Tue
                              Sep 3 21:52:28 UTC 2013 x86_64 x86_64
Alert Count                   4
First Seen                    2013-09-05 13:50:53 MSK
Last Seen                     2013-09-05 13:51:23 MSK
Local ID                      37be374f-05af-42d0-850b-84af99029b5d

Raw Audit Messages
type=AVC msg=audit(1378374683.421:907): avc:  denied  { write } for  pid=13760 comm="useradd" path="/dev/null" dev="sda2" ino=3943313 scontext=unconfined_u:unconfined_r:useradd_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:device_t:s0 tclass=file


type=SYSCALL msg=audit(1378374683.421:907): arch=x86_64 syscall=execve success=yes exit=0 a0=16c3d00 a1=16c2a60 a2=16c0340 a3=7ffffb925020 items=0 ppid=13753 pid=13760 auid=1000 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 ses=5 tty=pts0 comm=useradd exe=/usr/sbin/useradd subj=unconfined_u:unconfined_r:useradd_t:s0-s0:c0.c1023 key=(null)

Hash: useradd,useradd_t,device_t,file,write

Additional info:
reporter:       libreport-2.1.6
hashmarkername: setroubleshoot
kernel:         3.11.0-3.fc20.x86_64
type:           libreport

Potential duplicate: bug 861281