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the product is no longer active in Red Hat Bugzilla.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.
Description of problem:
We isolated problem [1] in customer's RHOSP 16.1 (based on RHEL 8.2) deployment when we tried to analyze SELinux status.
I was able to find Fedora bug https://bugzilla.redhat.com/show_bug.cgi?id=1713898, but it looks like fix wasn't backported to RHEL 8 yet, with RHEL 8.6 policy, the rule is not there either:
# sesearch -A -s snmpd_t -c cap_userns -p sys_ptrace
Commit that seem to address this problem:
commit adc572faae590e87ef91f8ba3ee8e99f92a531ea
Author: Lukas Vrabec <lvrabec>
Date: Tue Nov 26 14:50:46 2019 +0100
Allow snmpd_t domain to trace processes in user namespace
Resolves: rhbz#1713898
I understand that it is hard to justify backport to RHEL 8.2, but would be great to have this fix in RHEL 8.4 (many RHOSP users will rely on RHEL 8.4 for a while).
[1]
SELinux is preventing snmpd from sys_ptrace access on the cap_userns labeled snmpd_t.
***** Plugin catchall (100. confidence) suggests **************************
If you believe that snmpd should be allowed sys_ptrace access on cap_userns labeled snmpd_t by default.
Then you should report this as a bug.
You can generate a local policy module to allow this access.
Do
allow this access for now by executing:
# ausearch -c 'snmpd' --raw | audit2allow -M my-snmpd
# semodule -X 300 -i my-snmpd.pp
Additional Information:
Source Context system_u:system_r:snmpd_t:s0
Target Context system_u:system_r:snmpd_t:s0
Target Objects Unknown [ cap_userns ]
Source snmpd
Source Path snmpd
Port <Unknown>
Host hostname
Source RPM Packages
Target RPM Packages
Policy RPM selinux-policy-3.14.3-41.el8_2.9.noarch
Selinux Enabled True
Policy Type targeted
Enforcing Mode Permissive
Host Name hostname
Platform Linux hostname
4.18.0-193.65.2.el8_2.x86_64 #1 SMP Mon Aug 30
04:52:32 EDT 2021 x86_64 x86_64
Alert Count 32
First Seen 2022-03-21 19:25:06 UTC
Last Seen 2022-08-21 13:45:31 UTC
Local ID e12d319f-0335-4a96-8d64-33bd0e2d7a2d
Raw Audit Messages
type=AVC msg=audit(1661089531.866:11152269): avc: denied { sys_ptrace } for pid=4356 comm="snmpd" capability=19 scontext=system_u:system_r:snmpd_t:s0 tcontext=system_u:system_r:snmpd_t:s0 tclass=cap_userns permissive=1
Hash: snmpd,snmpd_t,snmpd_t,cap_userns,sys_ptrace
Version-Release number of selected component (if applicable):
RHEL 8.2
Alex,
This bz currently targets RHEL 8.8. If you need a backport to older releases, please follow you organization workflow to request it and add justification.
The following module can be use to check if the fix is sufficient:
# cat local_snmpd_userns_ptrace.cil
(allow snmpd_t snmpd_t (cap_userns (sys_ptrace)))
# semodule -i local_snmpd_userns_ptrace.cil
and then
# semodule -r local_snmpd_userns_ptrace
to remove it.
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.
For information on the advisory (selinux-policy bug fix and enhancement update), and where to find the updated
files, follow the link below.
If the solution does not work for you, open a new bug report.
https://access.redhat.com/errata/RHBA-2023:2965