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On 11/25/2011 08:32 PM, Stan Sander wrote: |
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> One of the more important things that is currently broken on my system |
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> when I switch on enforcing mode for SELinux is the su command. Mostly |
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> likely I've overlooked something so am asking here first before filing a |
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> bug on it. |
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After doing some more searching, reading, and educating of myself I have |
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been able to achieve the behavior I was wanting from the su command, |
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namely change my regular Linux uid to 0 and be able to launch graphical |
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programs if necessary when logged in to a desktop session. What I |
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discovered leaves my SELinux user id set to the user I originally logged |
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in as, which from a security and accountability standpoint is not a bad |
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thing, but the role and type are updated so all the transitions needed |
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for the policy to function as intended can occur. However, my Linux uid |
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is 0 so things that need that work. Probably a simple concept for all |
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you seasoned SELinux folk, but wanted to document it here for the |
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benefit of others who may find this in the archives. |
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My answer -- removing the calls to pam_selinux.so from the su file in |
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pam.d and also removing the calls to pam_xauth.so from the su and |
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newrole files. These (xauth) generated avc denials when they couldn't |
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access root's home area at /root due to (I think) ubac constraints. |
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The last step a very simple script I called sesu |
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#!/bin/bash |
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echo -n "X server: " |
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xhost local:localhost |
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echo -n "Enter root " |
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su -c "echo -n \"Enter current user \" && newrole -r sysadm_r" |
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If your PAM config doesn't allow the current user to su, then they get |
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permission denied. |
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If SELinux doesn't allow the current user to transition to a sysadm_r |
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then you get a root shell, but with limited capability. |
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-- |
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Stan & HD Tashi Grad 10/08 Edgewood, NM SWR |
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PR - Cindy and Jenny - Sammamish, WA NWR |
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http://www.cci.org |
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