Bug 1774233
| Summary: | Upgrading from 8.0 to 8.1 temporarily breaks sshd due to CASignatureAlgorithms | ||
|---|---|---|---|
| Product: | Red Hat Enterprise Linux 8 | Reporter: | Ravindra Patil <ravpatil> |
| Component: | crypto-policies | Assignee: | Tomas Mraz <tmraz> |
| Status: | CLOSED DUPLICATE | QA Contact: | BaseOS QE Security Team <qe-baseos-security> |
| Severity: | high | Docs Contact: | |
| Priority: | medium | ||
| Version: | 8.1 | CC: | nmavrogi |
| Target Milestone: | rc | ||
| Target Release: | 8.0 | ||
| Hardware: | Unspecified | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | If docs needed, set a value | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2019-11-20 08:15:17 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: | |||
Description of problem: We've started upgrading our 8.0 test systems to 8.1, and have hit the same issue on all of them with sshd crashing out with the error command-line: line 0: Bad configuration option: CASignatureAlgorithms In most cases, that's left systems which are being upgraded without ability to ssh for ~20 minutes while the number of packages being updated in 8.1. While tried to ssh its reporting following error for 'casignaturealgorithms' option [root@rhel8 ~]# ssh rhel8 /etc/crypto-policies/back-ends/openssh.config: line 6: Bad configuration option: casignaturealgorithms /etc/crypto-policies/back-ends/openssh.config: terminating, 1 bad configuration options Service was running but was not able to perform ssh. [root@rhel8 ~]# systemctl status sshd ● sshd.service - OpenSSH server daemon Loaded: loaded (/usr/lib/systemd/system/sshd.service; enabled; vendor preset: enabled) Active: active (running) since Wed 2019-11-20 01:53:46 IST; 1min 48s ago Docs: man:sshd(8) man:sshd_config(5) Main PID: 2909 (sshd) This is critical issue, as users should be allowed to perform ssh while the upgrade is in progress. That keeps happening until both libssh and crypto-policies have been updated (libssh presumably removed a CASignatureAlgorithm that crypto-policies is specifying in /etc/crypto-policies/back-ends/opensshserver.config). Version-Release number of selected component (if applicable): 20181217-6.git9a35207.el8.noarch How reproducible: Start upgrade from RHEL 8.0 to 8.1 # yum update -y Then try doing ssh from the same system to any other machine # ssh <server-ip> Steps to Reproduce: 1. Login to RHEL 8.0 2. Upgrade from RHEL 8.0 to 8.1 3. Try to perform ssh Actual results: sshd crashes with below output /etc/crypto-policies/back-ends/openssh.config: line 6: Bad configuration option: casignaturealgorithms /etc/crypto-policies/back-ends/openssh.config: terminating, 1 bad configuration options Expected results: SSHD should work fine. Additional info: Service was running but failed due to bad configuration option error for ' CASignatureAlgorithms' After sometime was able to ssh again when both packages libssh and crypto-policies were updated.