Bug 1898694
| Summary: | Add setgid capability into policy for tcsd | ||
|---|---|---|---|
| Product: | Red Hat Enterprise Linux 8 | Reporter: | Jerry Snitselaar <jsnitsel> |
| Component: | selinux-policy | Assignee: | Zdenek Pytela <zpytela> |
| Status: | CLOSED ERRATA | QA Contact: | Milos Malik <mmalik> |
| Severity: | medium | Docs Contact: | |
| Priority: | medium | ||
| Version: | 8.4 | CC: | ksrot, lvrabec, mmalik, plautrba, ssekidde |
| Target Milestone: | rc | Keywords: | Triaged |
| Target Release: | 8.4 | ||
| Hardware: | Unspecified | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | No Doc Update | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2021-05-18 14:58:17 UTC | Type: | Bug |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
| Bug Depends On: | |||
| Bug Blocks: | 1882414 | ||
Something is wrong on my RHEL-8.3 VM. The tcsd service won't start: # ls -l /dev/tpm* crw-rw----. 1 tss root 10, 224 Nov 20 17:07 /dev/tpm0 crw-rw----. 1 tss tss 253, 65536 Nov 20 17:07 /dev/tpmrm0 # ls -1Z /dev/tpm* system_u:object_r:tpm_device_t:s0 /dev/tpm0 system_u:object_r:tpm_device_t:s0 /dev/tpmrm0 # service tcsd start Redirecting to /bin/systemctl start tcsd.service Job for tcsd.service failed because the control process exited with error code. See "systemctl status tcsd.service" and "journalctl -xe" for details. # service tcsd status Redirecting to /bin/systemctl status tcsd.service ● tcsd.service - TCG Core Services Daemon Loaded: loaded (/usr/lib/systemd/system/tcsd.service; enabled; vendor preset: disabled) Active: failed (Result: exit-code) since Fri 2020-11-20 17:09:39 CET; 2s ago Process: 3656 ExecStart=/sbin/tcsd (code=exited, status=30) Nov 20 17:09:39 localhost.localdomain systemd[1]: Starting TCG Core Services Daemon... Nov 20 17:09:39 localhost.localdomain tcsd[3656]: TCSD TDDL[3656]: TrouSerS ioctl: (25) Inappropriate ioctl for device Nov 20 17:09:39 localhost.localdomain tcsd[3656]: TCSD TDDL[3656]: TrouSerS Falling back to Read/Write device support. Nov 20 17:09:39 localhost.localdomain tcsd[3656]: TCSD TCS[3656]: TrouSerS ERROR: TCS GetCapability failed with result = 0x1e Nov 20 17:09:39 localhost.localdomain systemd[1]: tcsd.service: Control process exited, code=exited status=30 Nov 20 17:09:39 localhost.localdomain systemd[1]: tcsd.service: Failed with result 'exit-code'. Nov 20 17:09:39 localhost.localdomain systemd[1]: Failed to start TCG Core Services Daemon. # No matter if SELinux is enforcing or permissive. Hi Milos, Can you verify that the VM has a TPM1.2 device and not a TPM2.0? It should also be TIS and not CRB, which is only TPM2.0. *** Bug 1901984 has been marked as a duplicate of this bug. *** I've submitted a Fedora PR to address the issue: https://github.com/fedora-selinux/selinux-policy/pull/498 This is the rawhide commit to backport:
commit 81c95e0d84bc442879302d905ac198f69732725a
Author: Zdenek Pytela <zpytela>
Date: Mon Dec 7 23:15:06 2020 +0100
Allow tcsd the setgid capability
Resolves: rhbz#1898694
diff --git a/policy/modules/contrib/tcsd.te b/policy/modules/contrib/tcsd.te
index 285ef0874..d541406dc 100644
--- a/policy/modules/contrib/tcsd.te
+++ b/policy/modules/contrib/tcsd.te
@@ -20,7 +20,7 @@ files_type(tcsd_var_lib_t)
# Local policy
#
-allow tcsd_t self:capability { dac_read_search dac_override setuid };
+allow tcsd_t self:capability { dac_read_search dac_override setgid setuid };
allow tcsd_t self:process { signal sigkill };
allow tcsd_t self:tcp_socket { accept listen };
The test fails as the service cannot start: Jan 7 02:33:12 prereserve-1mt-rhel-8 systemd[1]: Starting TCG Core Services Daemon... Jan 7 02:33:12 prereserve-1mt-rhel-8 journal[33623]: TCSD TDDL[33623]: TrouSerS ERROR: Could not find a device to open! Jan 7 02:33:12 prereserve-1mt-rhel-8 systemd[1]: tcsd.service: Control process exited, code=exited status=137 Jan 7 02:33:12 prereserve-1mt-rhel-8 systemd[1]: tcsd.service: Failed with result 'exit-code'. Jan 7 02:33:12 prereserve-1mt-rhel-8 systemd[1]: Failed to start TCG Core Services Daemon. # rpm -q trousers selinux-policy trousers-0.3.15-1.el8.x86_64 selinux-policy-3.14.3-59.el8.noarch The tcsd service requires a special piece of HW, which was not available on the Beaker machines. 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-2021:1639 |
Description of problem: A fix for the tcsd daemon in the trousers package makes use of setgid. While fixing a coverity scan complaint about checking the return value of setgid, I noticed that selinux didn't like tcsd trying to setgid. Zdenek Pytela suggests that a setgid capability should be added after: allow tcsd_t self:capability { dac_read_search dac_override setuid }; in contrib/tcsd.te Version-Release number of selected component (if applicable): How reproducible: Steps to Reproduce: 1. 2. 3. Actual results: Expected results: Additional info: