SELINUX_ERR op=security_compute_sid invalid_context while running /etc/init.d script of my app
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Doing this on a **RHEL8.10** distro.
I've created a user with *staff_u* role:
# useradd -Z staff_u testadm
And provided this user elevated permissions, for which did following steps:
1. created mysudoers file:
Did reboot. Installed my app's selinux policy module *(rpm)*. Then logged in with this *testadm* user, and ran this command to elevate to *sysadm_r:sysadm_t*: # sudo runcon -r sysadm_r -t sysadm_t -- su -
Now, on this console, with selinux **Enforcing**, I try running my application's executable (*maconfig*, which is internally running *
So naturally, I looked for denials in *
Found the explanation for the log - a process running as
So tried a couple of other things: 1. Switched selinux to **Permissive** mode (
Also got to know some more stuff from these pages: - https://wiki.gentoo.org/wiki/SELinux/Tutorials/Linux_services_and_the_system_u_SELinux_user#:~:text=warrants%20proper%20control.-,Linux%20service%20scripts,-Most%20Linux%20service - https://github.com/SELinuxProject/selinux-notebook/blob/main/src/auditing.md#general-selinux-audit-events ..but still not sure how to proceed. Pls help out if u can. Thanks in advance!
And provided this user elevated permissions, for which did following steps:
1. created mysudoers file:
/etc/sudoers.d/mysudoers
2. added this in it: %testadm ALL=(ALL) TYPE=sysadm_t ROLE=sysadm_r ALL
Did reboot. Installed my app's selinux policy module *(rpm)*. Then logged in with this *testadm* user, and ran this command to elevate to *sysadm_r:sysadm_t*: # sudo runcon -r sysadm_r -t sysadm_t -- su -
Now, on this console, with selinux **Enforcing**, I try running my application's executable (*maconfig*, which is internally running *
/etc/init.d/ma
* which is my app's script) and I'm getting this permission denied error:
[root@6H0RHEL810 ~]# /opt/McAfee/agent/bin/maconfig -stop
2025-04-25 11:43:12.768 (50811.50811) maconfig.Info: Stopping Trellix agent.
sh: /etc/init.d/ma: /bin/sh: bad interpreter: Permission denied
2025-04-25 11:43:12.770 (50811.50811) maconfig.Info: configuration finished
So naturally, I looked for denials in *
/var/log/audit/audit.log
* but got this kind of log instead:
type=SELINUX_ERR msg=audit(1745581392.769:2056): op=security_compute_sid invalid_context="staff_u:system_r:initrc_t:s0" scontext=staff_u:sysadm_r:sysadm_t:s0-s0:c0.c1023 tcontext=system_u:object_r:initrc_exec_t:s0 tclass=process
type=SYSCALL msg=audit(1745581392.769:2056): arch=c000003e syscall=59 success=no exit=-13 a0=5587d7a7b540 a1=5587d7a7c700 a2=5587d7a79e40 a3=0 items=0 ppid=50811 pid=50812 auid=1001 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=pts1 ses=8 comm="sh" exe="/usr/bin/bash" subj=staff_u:sysadm_r:sysadm_t:s0-s0:c0.c1023 key=(null)ARCH=x86_64 SYSCALL=execve AUID="testadm" UID="root" GID="root" EUID="root" SUID="root" FSUID="root" EGID="root" SGID="root" FSGID="root"
type=PROCTITLE msg=audit(1745581392.769:2056): proctitle=7368002D63002F6574632F696E69742E642F6D612073746F70
..which is not a straighforward avc
denial. So searched for ways to tackle this.
Found the explanation for the log - a process running as
sysadm_t
(maconfig) tried to run a file labeled initrc_exec_t
(*/etc/init.d/ma
*), and SELinux said "nope" because it would result in an invalid context transition to initrc_t
.
So tried a couple of other things: 1. Switched selinux to **Permissive** mode (
setenforce 0
), ran my app's command, it worked fine. Got some user_avc
denials. Added rules in policy for allowing those, *but didn't work* after setenforce 1
again
2. Added this *domain transition* rule to my policy *(didn't work)*: domain_auto_trans(sysadm_t, initrc_exec_t, initrc_t);
3. Tried adding these **role-type statements** in policy (*which I thought would work for sure but nope*):
require {
role system_r, sysadm_r;
type initrc_t;
}
role system_r types initrc_t;
#AND
role sysadm_r types initrc_t;
4. Added this rule (didn't work): allow sysadm_t initrc_exec_t:process transition;
Also got to know some more stuff from these pages: - https://wiki.gentoo.org/wiki/SELinux/Tutorials/Linux_services_and_the_system_u_SELinux_user#:~:text=warrants%20proper%20control.-,Linux%20service%20scripts,-Most%20Linux%20service - https://github.com/SELinuxProject/selinux-notebook/blob/main/src/auditing.md#general-selinux-audit-events ..but still not sure how to proceed. Pls help out if u can. Thanks in advance!
Asked by Chaitanya Singh
(31 rep)
Apr 26, 2025, 11:06 PM
Last activity: Apr 27, 2025, 06:42 AM
Last activity: Apr 27, 2025, 06:42 AM