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I get this SELinux alert even though I'm logging in as a regular user, not as root. Maybe it happens whenever a graphical app runs with elevated privileges, not sure. There don't seem to be any other problems due to this - just the alert. If I had settings in /root/.Xdefaults that matter for the apps running as root, they would probably be missing. Looks like an SELinux policy/labeling problem. Summary: SELinux is preventing /usr/libexec/gdm-simple-slave "read" access on /root/.Xdefaults. Detailed Description: SELinux denied access requested by gdm-simple-slav. It is not expected that this access is required by gdm-simple-slav 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://docs.fedoraproject.org/selinux-faq-fc5/#id2961385) Please file a bug report. Additional Information: Source Context system_u:system_r:xdm_t:s0-s0:c0.c1023 Target Context system_u:object_r:admin_home_t:s0 Target Objects /root/.Xdefaults [ file ] Source gdm-simple-slav Source Path /usr/libexec/gdm-simple-slave Port <Unknown> Host (removed) Source RPM Packages gdm-2.28.2-1.fc12 Target RPM Packages Policy RPM selinux-policy-3.6.32-73.fc12 Selinux Enabled True Policy Type targeted Enforcing Mode Enforcing Plugin Name catchall Host Name (removed) Platform Linux (removed) 2.6.31.12-174.2.3.fc12.x86_64 #1 SMP Mon Jan 18 19:52:07 UTC 2010 x86_64 x86_64 Alert Count 42 First Seen Tue 12 Jan 2010 09:33:44 PM PST Last Seen Sun 31 Jan 2010 01:24:20 PM PST Local ID c08d7e59-ab10-48ba-9cc1-b39c80e3a50d Line Numbers Raw Audit Messages node=(removed) type=AVC msg=audit(1264973060.387:12): avc: denied { read } for pid=1791 comm="gdm-simple-slav" name=".Xdefaults" dev=dm-0 ino=50712 scontext=system_u:system_r:xdm_t:s0-s0:c0.c1023 tcontext=system_u:object_r:admin_home_t:s0 tclass=file node=(removed) type=SYSCALL msg=audit(1264973060.387:12): arch=c000003e syscall=2 success=no exit=-13 a0=7fffc3ad9980 a1=0 a2=fef a3=1999999999999999 items=0 ppid=1714 pid=1791 auid=4294967295 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=(none) ses=4294967295 comm="gdm-simple-slav" exe="/usr/libexec/gdm-simple-slave" subj=system_u:system_r:xdm_t:s0-s0:c0.c1023 key=(null) Hash String generated from selinux-policy-3.6.32-73.fc12,catchall,gdm-simple-slav,xdm_t,admin_home_t,file,read audit2allow suggests: #============= xdm_t ============== allow xdm_t admin_home_t:file read;
Bug 505797 (reported against F11) seems to be related to this bug.
Remove this file from the /root directory and it will stop complaining. I think this got created when you logged in as root via X?
Well, sure, removing the file will get rid of the alert and one can make all kinds of arguments that running X as root is not advisable. However, that's a policy question that is orthogonal to the problem at hand. There may be legitimate reasons why root needs a .Xdefaults file. Also, the alert did not happen under F10 and suddenly started with F12, so something about the SELinux configuration has changed and the access denial is - I think - unintended. There have been lots of unintended SELinux access denials in the past where the solution was to revise the SELinux policy definitions - why not this time? Just to be sure: I put the .Xdefaults there deliberately. It contains my preferences for X properties such as xterm font and colors, keyboard shortcuts for window scrolling, etc. - just settings I rely on when running X (if that's as root it's only for rare troubleshooting purposes, but it has been useful before). FWIW: I noticed that every time I reboot another 7 occurrences of this alert are created but not when I start a graphical app, even when it requires entering the root password (e.g. a tool from the System->Administration menu). So, to summarize: I'm not disputing that root shouldn't run X. It just seems this access denial is not serving a useful purpose and may in fact be unintended.
Ok, we could label it xdm_home_t. # semanage fcontext -a -t xdm_home_t /root/.Xdefaults # restorecon -R -v /root And then it the AVC will go away. This would allow a corrupted xdm to write to this file. We could label it with a gnome label gnome_home_t. Like these. /root/\.config(/.*)? gen_context(system_u:object_r:gnome_home_t,s0) /root/\.gconf(d)?(/.*)? gen_context(system_u:object_r:gconf_home_t,s0) /root/\.gnome2(/.*)? gen_context(system_u:object_r:gnome_home_t,s0) /root/\.local.* gen_context(system_u:object_r:gconf_home_t,s0) /root/\.pulse(/.*)? gen_context(system_u:object_r:gnome_home_t,s0) /root/\.gstreamer-.* gen_context(system_u:object_r:gstreamer_home_t,s0) And then xdm could read it. Or we can create a new label for it. xserver_conf_t?
This sounds good. I don't know enough about SELinux or xdm to comment on the finer details of which approach is better but read access is probably sufficient. It's your call.
For now Richard, just label it xdm_home_t chcon -t xdm_home_t /root/.Xdefaults
Miroslav add /root/\.Xdefaults gen_context(system_u:object_r:gnome_home_t,s0)
Fixed in selinux-policy-3.6.32-82.fc12
selinux-policy-3.6.32-82.fc12 has been submitted as an update for Fedora 12. http://admin.fedoraproject.org/updates/selinux-policy-3.6.32-82.fc12
selinux-policy-3.6.32-84.fc12 has been pushed to the Fedora 12 testing repository. If problems still persist, please make note of it in this bug report. If you want to test the update, you can install it with su -c 'yum --enablerepo=updates-testing update selinux-policy'. You can provide feedback for this update here: http://admin.fedoraproject.org/updates/F12/FEDORA-2010-1492
selinux-policy-3.6.32-84.fc12 has been pushed to the Fedora 12 stable repository. If problems still persist, please make note of it in this bug report.