Description of problem:
As of today (which is the first time I logged off since last week, so it could be caused by any update in the last week or so) I can no longer login graphically using any user (both local and winbind). Login through text terminal or SSH still works well as well as sudo (I haven't tried anything else).

I haven't found anything interesting in the logs, except this from /var/log/secure:
---8<---
Apr 19 16:34:49 chen pam: gdm-password[2626]: pam_unix(gdm-password:auth): authentication failure; logname= uid=0 euid=0 tty=:0 ruser= rhost=  user=oded.a
---8<---
(Which interestingly enough reports failures for any user except root - failing to log in as root does not generate a failure line in /var/log/secure).

And this from /var/log/messages:
---8<---
Apr 19 16:34:38 chen setroubleshoot: SELinux prevented kde4-config from writing .kde. For complete SELinux messages. run sealert -l a08e9abb-f598-4ebb-b47a-d9c6557ab07d
Apr 19 16:34:46 chen setroubleshoot: SELinux is preventing gdm-session-wor (xdm_t) "read" home_root_t. For complete SELinux messages. run sealert -l 763f61fe-92b2-4add-ab04-a98dbd91d2d3
Apr 19 16:35:51 chen setroubleshoot: SELinux is preventing gdm-simple-gree (xdm_t) "read" to oded.a (home_root_t). For complete SELinux messages. run sealert -l a5f3b4e5-46de-4f37-a088-ecc07b152a53
---8<---

I get similar errors about sshd trying to "read" from home_root_t but logins through ssh work, so I'm not sure that is related.

Here is the complete sealert report anyway, for completion:

Summary:

SELinux is preventing gdm-session-wor (xdm_t) "read" home_root_t.

Detailed Description:

SELinux denied access requested by gdm-session-wor. It is not expected that this
access is required by gdm-session-wor and this access may signal an intrusion
attempt. It is also possible that the specific version or configuration of the
application is causing it to require additional access.

Allowing Access:

You can generate a local policy module to allow this access - see FAQ
(http://fedora.redhat.com/docs/selinux-faq-fc5/#id2961385) Or you can disable
SELinux protection altogether. Disabling SELinux protection is not recommended.
Please file a bug report (http://bugzilla.redhat.com/bugzilla/enter_bug.cgi)
against this package.

Additional Information:

Source Context                system_u:system_r:xdm_t:s0-s0:c0.c1023
Target Context                unconfined_u:object_r:home_root_t:s0
Target Objects                .dmrc [ file ]
Source                        gdm-session-wor
Source Path                   /usr/libexec/gdm-session-worker
Port                          <Unknown>
Host                          chen.office.taboola.com
Source RPM Packages           gdm-2.26.1-1.fc11
Target RPM Packages           
Policy RPM                    selinux-policy-3.6.12-4.fc11
Selinux Enabled               True
Policy Type                   targeted
MLS Enabled                   True
Enforcing Mode                Enforcing
Plugin Name                   catchall
Host Name                     chen.office.taboola.com
Platform                      Linux chen.office.taboola.com
                              2.6.29.1-68.fc11.x86_64 #1 SMP Sat Apr 11 02:20:46
                              EDT 2009 x86_64 x86_64
Alert Count                   7
First Seen                    Mon Apr 13 14:29:14 2009
Last Seen                     Sun Apr 19 16:30:27 2009
Local ID                      763f61fe-92b2-4add-ab04-a98dbd91d2d3
Line Numbers                  

Raw Audit Messages            

node=chen.office.taboola.com type=AVC msg=audit(1240147827.179:1012): avc:  denied  { read } for  pid=23167 comm="gdm-session-wor" name=".dmrc" dev=dm-1 ino=4882 scontext=system_u:system_r:xdm_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:home_root_t:s0 tclass=file

node=chen.office.taboola.com type=SYSCALL msg=audit(1240147827.179:1012): arch=c000003e syscall=2 success=no exit=-13 a0=18d61e0 a1=0 a2=0 a3=2 items=0 ppid=22344 pid=23167 auid=4294967295 uid=0 gid=0 euid=16777216 suid=0 fsuid=16777216 egid=16777216 sgid=0 fsgid=16777216 tty=(none) ses=4294967295 comm="gdm-session-wor" exe="/usr/libexec/gdm-session-worker" subj=system_u:system_r:xdm_t:s0-s0:c0.c1023 key=(null)


Version-Release number of selected component (if applicable):
2.26.1

How reproducible:
Always

Steps to Reproduce:
1. Log off
2. try to log in by choosing "other", typing the user name and password
  
Actual results:
GDM reports "Unable to authenticate the user"

Expected results:
GDM should start the desktop session properly.

Additional info:
I'm using winbind to authenticate against an active directory domain, which normally works great.