Note: This bug is displayed in read-only format because the product is no longer active in Red Hat Bugzilla.
RHEL Engineering is moving the tracking of its product development work on RHEL 6 through RHEL 9 to Red Hat Jira (issues.redhat.com). If you're a Red Hat customer, please continue to file support cases via the Red Hat customer portal. If you're not, please head to the "RHEL project" in Red Hat Jira and file new tickets here. Individual Bugzilla bugs in the statuses "NEW", "ASSIGNED", and "POST" are being migrated throughout September 2023. Bugs of Red Hat partners with an assigned Engineering Partner Manager (EPM) are migrated in late September as per pre-agreed dates. Bugs against components "kernel", "kernel-rt", and "kpatch" are only migrated if still in "NEW" or "ASSIGNED". If you cannot log in to RH Jira, please consult article #7032570. That failing, please send an e-mail to the RH Jira admins at rh-issues@redhat.com to troubleshoot your issue as a user management inquiry. The email creates a ServiceNow ticket with Red Hat. Individual Bugzilla bugs that are migrated will be moved to status "CLOSED", resolution "MIGRATED", and set with "MigratedToJIRA" in "Keywords". The link to the successor Jira issue will be found under "Links", have a little "two-footprint" icon next to it, and direct you to the "RHEL project" in Red Hat Jira (issue links are of type "https://issues.redhat.com/browse/RHEL-XXXX", where "X" is a digit). This same link will be available in a blue banner at the top of the page informing you that that bug has been migrated.

Bug 700713

Summary: w command executed as staff_u under sudo produce AVC
Product: Red Hat Enterprise Linux 6 Reporter: Karel Srot <ksrot>
Component: selinux-policyAssignee: Daniel Walsh <dwalsh>
Status: CLOSED NOTABUG QA Contact: BaseOS QE Security Team <qe-baseos-security>
Severity: medium Docs Contact:
Priority: medium    
Version: 6.1CC: dwalsh, mmalik
Target Milestone: rc   
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2011-04-29 14:00:33 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 Karel Srot 2011-04-29 07:09:42 UTC
Description of problem:

[root@dhcp-30-102 ~]# rpm -q sudo selinux-policy 
sudo-1.7.4p5-5.el6.x86_64
selinux-policy-3.7.19-87.el6.noarch

1. useradd -Z staff_u -m testuser
2. passwd testuser
3. echo 'testuser	ALL = (root) ALL' >> /etc/sudoers
4. ssh testuser@localhost
5. sudo w
6. exit

AVCs below appears in audit.log. 'w' executed without sudo doesn't produce AVC.

time->Fri Apr 29 09:05:09 2011
type=SYSCALL msg=audit(1304060709.931:869): arch=c000003e syscall=0 success=yes exit=198 a0=4 a1=3192e118a0 a2=3ff a3=fffffffc items=0 ppid=8009 pid=8016 auid=502 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=pts9 ses=21 comm="w" exe="/usr/bin/w" subj=staff_u:staff_r:staff_t:s0 key=(null)
type=AVC msg=audit(1304060709.931:869): avc:  denied  { sys_ptrace } for  pid=8016 comm="w" capability=19  scontext=staff_u:staff_r:staff_t:s0 tcontext=staff_u:staff_r:staff_t:s0 tclass=capability
----
time->Fri Apr 29 09:05:09 2011
type=SYSCALL msg=audit(1304060709.931:870): arch=c000003e syscall=0 success=yes exit=189 a0=4 a1=3192e118a0 a2=3ff a3=fffffffc items=0 ppid=8009 pid=8016 auid=502 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=pts9 ses=21 comm="w" exe="/usr/bin/w" subj=staff_u:staff_r:staff_t:s0 key=(null)
type=AVC msg=audit(1304060709.931:870): avc:  denied  { sys_ptrace } for  pid=8016 comm="w" capability=19  scontext=staff_u:staff_r:staff_t:s0 tcontext=staff_u:staff_r:staff_t:s0 tclass=capability
----
time->Fri Apr 29 09:05:09 2011
type=SYSCALL msg=audit(1304060709.932:871): arch=c000003e syscall=62 success=no exit=-13 a0=a12 a1=0 a2=7b2d50 a3=fffffffc items=0 ppid=8009 pid=8016 auid=502 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=pts9 ses=21 comm="w" exe="/usr/bin/w" subj=staff_u:staff_r:staff_t:s0 key=(null)
type=AVC msg=audit(1304060709.932:871): avc:  denied  { signull } for  pid=8016 comm="w" scontext=staff_u:staff_r:staff_t:s0 tcontext=system_u:system_r:xdm_t:s0-s0:c0.c1023 tclass=process
----
time->Fri Apr 29 09:05:09 2011
type=SYSCALL msg=audit(1304060709.933:872): arch=c000003e syscall=62 success=no exit=-1 a0=cfd a1=0 a2=7bde60 a3=fffffffb items=0 ppid=8009 pid=8016 auid=502 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=pts9 ses=21 comm="w" exe="/usr/bin/w" subj=staff_u:staff_r:staff_t:s0 key=(null)
type=AVC msg=audit(1304060709.933:872): avc:  denied  { kill } for  pid=8016 comm="w" capability=5  scontext=staff_u:staff_r:staff_t:s0 tcontext=staff_u:staff_r:staff_t:s0 tclass=capability
----
time->Fri Apr 29 09:05:09 2011
type=SYSCALL msg=audit(1304060709.933:873): arch=c000003e syscall=62 success=no exit=-13 a0=1f29 a1=0 a2=7c0ce0 a3=fffffffb items=0 ppid=8009 pid=8016 auid=502 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=pts9 ses=21 comm="w" exe="/usr/bin/w" subj=staff_u:staff_r:staff_t:s0 key=(null)
type=AVC msg=audit(1304060709.933:873): avc:  denied  { signull } for  pid=8016 comm="w" scontext=staff_u:staff_r:staff_t:s0 tcontext=system_u:system_r:sshd_t:s0-s0:c0.c1023 tclass=process
----
time->Fri Apr 29 09:05:09 2011
type=SYSCALL msg=audit(1304060709.933:874): arch=c000003e syscall=62 success=no exit=-1 a0=cfd a1=0 a2=7bef50 a3=fffffffa items=0 ppid=8009 pid=8016 auid=502 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=pts9 ses=21 comm="w" exe="/usr/bin/w" subj=staff_u:staff_r:staff_t:s0 key=(null)
type=AVC msg=audit(1304060709.933:874): avc:  denied  { kill } for  pid=8016 comm="w" capability=5  scontext=staff_u:staff_r:staff_t:s0 tcontext=staff_u:staff_r:staff_t:s0 tclass=capability

Comment 1 Karel Srot 2011-04-29 07:10:27 UTC
I forgot to mention that { sys_ptrace } appears even if allow_ptrace is on.

Comment 2 Daniel Walsh 2011-04-29 14:00:33 UTC
staff_t is not a domain that can run as root.  If you want to run as root you need to transition to a confined root role, like sysadm_t or unconfined_t.  Or you can develop new ones like webadm_t.

Comment 3 Daniel Walsh 2011-04-29 14:01:33 UTC
echo 'testuser ALL = (root) ROLE=sysadm_r TYPE=sysadm_t ALL' >> /etc/sudoers

Will cause your staff_r:staff_t to transition to sysadm_r:sysadm_t when it runs through sudo.