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Bug 1532079
| Summary: | SELinux is preventing dnsmasq from updating the nameserver list via dbus | ||
|---|---|---|---|
| Product: | [Fedora] Fedora | Reporter: | Pablo Hess <phess> |
| Component: | selinux-policy-targeted | Assignee: | Lukas Vrabec <lvrabec> |
| Status: | CLOSED ERRATA | QA Contact: | Ben Levenson <benl> |
| Severity: | low | Docs Contact: | |
| Priority: | unspecified | ||
| Version: | 27 | CC: | dwalsh |
| Target Milestone: | --- | ||
| Target Release: | --- | ||
| 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: | 2018-02-27 17:21:36 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: | |||
selinux-policy-3.13.1-283.26.fc27 has been submitted as an update to Fedora 27. https://bodhi.fedoraproject.org/updates/FEDORA-2018-a9711c96b2 selinux-policy-3.13.1-283.26.fc27 has been pushed to the Fedora 27 testing repository. If problems still persist, please make note of it in this bug report. See https://fedoraproject.org/wiki/QA:Updates_Testing for instructions on how to install test updates. You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2018-a9711c96b2 selinux-policy-3.13.1-283.26.fc27 has been pushed to the Fedora 27 stable repository. If problems still persist, please make note of it in this bug report. |
Description of problem: SELinux policy targeted as provided on Fedora 27 prevents dnsmasq from sending messages over dbus to (as far as I understand) acknowledge changes in the nameserver list. When connecting to a VPN, dnsmasq will not update the nameserver list and will keep using the old nameservers. Typical AVC under Permissive mode: type=USER_AVC msg=audit(1515355945.646:1293): pid=939 uid=81 auid=4294967295 ses=4294967295 subj=system_u:system_r:system_dbusd_t:s0-s0:c0.c1023 msg='avc: denied { send_msg } for msgtype=method_return dest=:1.333 spid=9390 tpid=16945 scontext=system_u:system_r:dnsmasq_t:s0 tcontext=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 tclass=dbus permissive=1 exe="/usr/bin/dbus-daemon" sauid=81 hostname=? addr=? terminal=?' Version-Release number of selected component (if applicable): Fedora 27 selinux-policy-targeted-3.13.1-283.17.fc27.noarch dnsmasq-2.78-1.fc27.x86_64 NetworkManager-1.8.4-7.fc27.x86_64 NetworkManager-openvpn-1.8.0-3.fc27.x86_64 openvpn-2.4.4-1.fc27.x86_64 NetworkManager-openvpn-gnome-1.8.0-3.fc27.x86_64 How reproducible: Every time. Steps to Reproduce: 1. Set NetworkManager to use dnsmasq as DNS manager (dns=dnsmasq in NetworkManager.conf) and restart NetworkManager 2. Connect to a VPN on OpenVPN 3. Try to resolve a hostname on the VPN without manually setting your nameservers to include the VPN's. Actual results: Internal VPN hostname will fail to resolve -- VPN's nameserver won't be queried at all. Expected results: Internal VPN hostname should be resolved by the VPN nameserver. Additional info: Confirmed failure to even get a version number from dnsmasq through dbus using gdbus CLI utility: $ sudo setenforce 1 $ sudo gdbus call -y -d org.freedesktop.NetworkManager.dnsmasq -o /uk/org/thekelleys/dnsmasq -m uk.org.thekelleys.dnsmasq.GetVersion (FAILURE MESSAGE) $ sudo setenforce 0 $ sudo gdbus call -y -d org.freedesktop.NetworkManager.dnsmasq -o /uk/org/thekelleys/dnsmasq -m uk.org.thekelleys.dnsmasq.GetVersion ('2.78',) In addition, "audit2allow -M dnsmasq-selinux-dbus" produced a TE module with this content: ~~~ module dnsmasq-selinux-dbus 1.0; require { type dnsmasq_t; type unconfined_t; class dbus send_msg; } #============= dnsmasq_t ============== allow dnsmasq_t unconfined_t:dbus send_msg; ~~~ Curiously enough, NetworkManager is *not* running with unconfined_t but NetworkManager_t as expected. I loaded the new module and the problem is now fixed.