Bug 903828

Summary: SELinux is preventing /usr/sbin/lightdm from using the 'sigchld' accesses on a process.
Product: [Fedora] Fedora Reporter: Garrett Holmstrom <gholms>
Component: selinux-policyAssignee: Miroslav Grepl <mgrepl>
Status: CLOSED CURRENTRELEASE QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: unspecified Docs Contact:
Priority: unspecified    
Version: 18CC: bucketofsnow, dominick.grift, dwalsh, mgrepl, rdieter
Target Milestone: ---   
Target Release: ---   
Hardware: x86_64   
OS: Unspecified   
Whiteboard: abrt_hash:f57bb44e079a0478731453d87798e249e234280512ea183439a6443fc30baa4f
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2013-02-08 02:23:45 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:

Description Garrett Holmstrom 2013-01-24 21:48:53 UTC
Description of problem:
On a fresh F18 install with XFCE, I tried to log in as an account with a staff_u login.
SELinux is preventing /usr/sbin/lightdm from using the 'sigchld' accesses on a process.

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

If you believe that lightdm should be allowed sigchld access on processes labeled xdm_t 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 lightdm /var/log/audit/audit.log | audit2allow -M mypol
# semodule -i mypol.pp

Additional Information:
Source Context                staff_u:staff_r:staff_ssh_agent_t:s0-s0:c0.c1023
Target Context                system_u:system_r:xdm_t:s0-s0:c0.c1023
Target Objects                 [ process ]
Source                        lightdm
Source Path                   /usr/sbin/lightdm
Port                          <Unknown>
Host                          (removed)
Source RPM Packages           
Target RPM Packages           
Policy RPM                    selinux-policy-3.11.1-71.fc18.noarch
Selinux Enabled               True
Policy Type                   targeted
Enforcing Mode                Permissive
Host Name                     (removed)
Platform                      Linux (removed) 3.7.2-204.fc18.x86_64 #1 SMP Wed
                              Jan 16 16:22:52 UTC 2013 x86_64 x86_64
Alert Count                   2
First Seen                    2013-01-24 13:36:10 PST
Last Seen                     2013-01-24 13:40:45 PST
Local ID                      b8212126-df1c-4368-b4d0-06a75f1e2bb5

Raw Audit Messages
type=AVC msg=audit(1359063645.610:354): avc:  denied  { sigchld } for  pid=1362 comm="lightdm" scontext=staff_u:staff_r:staff_ssh_agent_t:s0-s0:c0.c1023 tcontext=system_u:system_r:xdm_t:s0-s0:c0.c1023 tclass=process


Hash: lightdm,staff_ssh_agent_t,xdm_t,process,sigchld

audit2allow

#============= staff_ssh_agent_t ==============
allow staff_ssh_agent_t xdm_t:process sigchld;

audit2allow -R

#============= staff_ssh_agent_t ==============
allow staff_ssh_agent_t xdm_t:process sigchld;


Additional info:
hashmarkername: setroubleshoot
kernel:         3.7.2-204.fc18.x86_64
type:           libreport

Comment 1 Miroslav Grepl 2013-01-25 10:05:33 UTC
Garrett,
did it happen if you started to use staff_r SELinux role? Or does it repeat?

Comment 2 Garrett Holmstrom 2013-01-25 17:44:46 UTC
I logged in as root immediately after installing and added an selinux login for this user, so I haven't logged in as anything other than staff_u:staff_r:staff_t so far.  If it matters, I have used sudo to get a staff_u:unconfined_r:unconfined_t root shell a few times.  Does that answer your question?

I will see if I can get it to show up again today just to be sure.  That way I try it on a freshly-booted system, too.

Comment 3 Daniel Walsh 2013-01-28 20:13:59 UTC
4d299de59999a1e4c5254fac92d11b8d8402d872 checked into git to allow this.

We should allow all user programs to sigchld login programs.

Comment 4 Miroslav Grepl 2013-01-30 09:52:23 UTC
Fixed in selinux-policy-3.11.1-74.fc18.noarch

Comment 5 Fedora Update System 2013-01-31 13:18:32 UTC
selinux-policy-3.11.1-74.fc18 has been submitted as an update for Fedora 18.
https://admin.fedoraproject.org/updates/selinux-policy-3.11.1-74.fc18

Comment 6 Fedora Update System 2013-02-01 16:39:05 UTC
Package selinux-policy-3.11.1-74.fc18:
* should fix your issue,
* was pushed to the Fedora 18 testing repository,
* should be available at your local mirror within two days.
Update it with:
# su -c 'yum update --enablerepo=updates-testing selinux-policy-3.11.1-74.fc18'
as soon as you are able to.
Please go to the following url:
https://admin.fedoraproject.org/updates/FEDORA-2013-1693/selinux-policy-3.11.1-74.fc18
then log in and leave karma (feedback).

Comment 7 Kevin Fenzi 2013-02-03 02:21:46 UTC
*** Bug 906164 has been marked as a duplicate of this bug. ***

Comment 8 Garrett Holmstrom 2013-02-05 00:42:23 UTC
Works for me.  Thanks!

Comment 9 Fedora Update System 2013-02-08 02:23:47 UTC
selinux-policy-3.11.1-74.fc18 has been pushed to the Fedora 18 stable repository.  If problems still persist, please make note of it in this bug report.