I believe it won't happen again. If I am wrong, please reopen the bug. Thank you.

It happened again

SELinux is preventing /usr/libexec/gdm-session-worker from using the 'transition' accesses on a process.

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

If vous pensez que gdm-session-worker devrait être autorisé à accéder transition sur les processus étiquetés xdm_t par défaut.
Then vous devriez rapporter ceci en tant qu'anomalie.
Vous pouvez générer un module de stratégie local pour autoriser cet accès.
Do
autoriser cet accès pour le moment en exécutant :
# grep gdm-session-wor /var/log/audit/audit.log | audit2allow -M mypol
# semodule -i mypol.pp

Additional Information:
Source Context                system_u:system_r:xdm_t:s0-s0:c0.c1023
Target Context                system_u:system_r:xdm_t:s0-s0:c0.c1023
Target Objects                /usr/libexec/gdm-session-worker [ process ]
Source                        gdm-session-wor
Source Path                   /usr/libexec/gdm-session-worker
Port                          <Inconnu>
Host                          (removed)
Source RPM Packages           gdm-3.9.90-1.fc21.x86_64
Target RPM Packages           gdm-3.9.90-1.fc21.x86_64
Policy RPM                    selinux-policy-3.12.1-76.fc21.noarch
Selinux Enabled               True
Policy Type                   targeted
Enforcing Mode                Enforcing
Host Name                     (removed)
Platform                      Linux (removed) 3.11.0-3.fc21.x86_64 #1 SMP Tue
                              Sep 3 21:52:46 UTC 2013 x86_64 x86_64
Alert Count                   18
First Seen                    2013-09-06 09:53:37 CEST
Last Seen                     2013-09-06 09:55:12 CEST
Local ID                      5db17184-3113-4a88-a47f-a2cc45bd9e36

Raw Audit Messages
type=AVC msg=audit(1378454112.796:6550): avc:  denied  { transition } for  pid=32657 comm="gdm-simple-slav" path="/usr/libexec/gdm-session-worker" dev="dm-0" ino=2797788 scontext=system_u:system_r:xdm_t:s0-s0:c0.c1023 tcontext=system_u:system_r:xdm_t:s0-s0:c0.c1023 tclass=process


type=SYSCALL msg=audit(1378454112.796:6550): arch=x86_64 syscall=execve success=no exit=EACCES a0=7f9896d72e90 a1=7f9896d76318 a2=7f9896d766d0 a3=7fff35900d10 items=0 ppid=18427 pid=32657 auid=4294967295 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 ses=4294967295 tty=(none) comm=gdm-simple-slav exe=/usr/libexec/gdm-simple-slave subj=system_u:system_r:xdm_t:s0-s0:c0.c1023 key=(null)

Hash: gdm-session-wor,xdm_t,xdm_t,process,transition

86a0dd1831acf88a2e826394743d777d2b1a8fde Allows this in git.

Miroslav lets just add it, since it really does not add any access.  A process is able to transition to itself.

This bug appears to have been reported against 'rawhide' during the Fedora 20 development cycle.
Changing version to '20'.

More information and reason for this action is here:
https://fedoraproject.org/wiki/BugZappers/HouseKeeping/Fedora20

selinux-policy-3.12.1-83.fc20 has been submitted as an update for Fedora 20.
https://admin.fedoraproject.org/updates/selinux-policy-3.12.1-83.fc20

Package selinux-policy-3.12.1-83.fc20:
* should fix your issue,
* was pushed to the Fedora 20 testing repository,
* should be available at your local mirror within two days.
Update it with:
# su -c 'yum update --enablerepo=updates-testing selinux-policy-3.12.1-83.fc20'
as soon as you are able to.
Please go to the following url:
https://admin.fedoraproject.org/updates/FEDORA-2013-17722/selinux-policy-3.12.1-83.fc20
then log in and leave karma (feedback).

Package selinux-policy-3.12.1-84.fc20:
* should fix your issue,
* was pushed to the Fedora 20 testing repository,
* should be available at your local mirror within two days.
Update it with:
# su -c 'yum update --enablerepo=updates-testing selinux-policy-3.12.1-84.fc20'
as soon as you are able to.
Please go to the following url:
https://admin.fedoraproject.org/updates/FEDORA-2013-17722/selinux-policy-3.12.1-84.fc20
then log in and leave karma (feedback).

This message is a reminder that Fedora 20 is nearing its end of life.
Approximately 4 (four) weeks from now Fedora will stop maintaining
and issuing updates for Fedora 20. It is Fedora's policy to close all
bug reports from releases that are no longer maintained. At that time
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Fedora 20 changed to end-of-life (EOL) status on 2015-06-23. Fedora 20 is
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