Bug 1739081

Summary: [Regression] DHCPv4 does not work on dnsmasq-2.80-8.fc31
Product: [Fedora] Fedora Reporter: Gris Ge <fge>
Component: dnsmasqAssignee: Petr Menšík <pemensik>
Status: CLOSED ERRATA QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: urgent Docs Contact:
Priority: urgent    
Version: 31CC: bugzilla, code, dougsland, itamar, jima, laine, p, pemensik, thozza, vbenes, veillard
Target Milestone: ---Keywords: Regression
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard:
Fixed In Version: dnsmasq-2.80-9.fc30 Doc Type: If docs needed, set a value
Doc Text:
Story Points: ---
Clone Of:
: 1739797 (view as bug list) Environment:
Last Closed: 2019-08-22 01:17:20 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: 1739797    

Description Gris Ge 2019-08-08 12:57:40 UTC
Description of problem:

With dnsmasq-2.80-8.fc31, the DHCPv4 does not any more.

And it also generates a flood of RA advertisement.

After downgrade to dnsmasq-2.79-7.fc29, all goes well.


Version-Release number of selected component (if applicable):
dnsmasq-2.80-8.fc31.x86_64

How reproducible:
100%

Steps to Reproduce:

sudo ip link add dhcpcli type veth peer name dhcpsrv
sudo ip link set up dhcpcli
sudo ip netns add nmstate_test
sudo ip link set dhcpsrv netns nmstate_test
sudo ip netns exec nmstate_test ip link set up dhcpsrv
sudo ip netns exec nmstate_test ip addr add 192.0.2.251/24 dev dhcpsrv
sudo ip netns exec nmstate_test \
    dnsmasq --dhcp-range=192.0.2.100,192.0.2.200,255.255.255.0 \
    --interface=dhcpsrv
sudo dhclient -d dhcpcli



Actual results:
DHCPv4 not work

Expected results:
DHCPv4 works

Additional info:

Comment 1 Petr Menšík 2019-08-09 13:08:02 UTC
Ok, confirm it is broken. Not sure yet for right reason. I tried to fix failing build on rawhide by quick support for SO_TIMESTAMP. I think that broken it completely. Would disable it and just skip SIOCGSTAMP if not defined.

Comment 2 Petr Menšík 2019-08-09 13:35:26 UTC
Fixed in commit [1]. But removing SO_TIMESTAMP seems to fixed issue. It seems there is another issue with high CPU usage in all 2.80 versions.

1. https://src.fedoraproject.org/rpms/dnsmasq/c/bde34f977c037ecb05757b5feea0a05ba6c856ae

Comment 3 Chris Murphy 2019-08-10 01:31:51 UTC
I've run into this as well. Rawhide host has no apparent problem; but any qemu-kvm guest has no network connection, because ipv4 isn't being assigned to the guest.

In the working case, I see these lines in the host's journal, when the VM is starting up:
[   99.883685] fmac.local dnsmasq-dhcp[1112]: DHCPDISCOVER(virbr0) 52:54:00:7c:25:f9
[   99.884350] fmac.local dnsmasq-dhcp[1112]: DHCPOFFER(virbr0) 192.168.122.175 52:54:00:7c:25:f9
[   99.884663] fmac.local dnsmasq-dhcp[1112]: DHCPREQUEST(virbr0) 192.168.122.175 52:54:00:7c:25:f9
[   99.884785] fmac.local dnsmasq-dhcp[1112]: DHCPACK(virbr0) 192.168.122.175 52:54:00:7c:25:f9 localhost-live

Those lines don't exist in the non-working case.

Updating to -9 or downgrading to -4 fixes the problem.
https://kojipkgs.fedoraproject.org//packages/dnsmasq/2.80/9.fc31/x86_64/dnsmasq-2.80-9.fc31.x86_64.rpm

Comment 4 Vladimir Benes 2019-08-10 15:00:09 UTC
high cpu usage is filed here: https://bugzilla.redhat.com/show_bug.cgi?id=1739797

Comment 5 Vladimir Benes 2019-08-10 15:00:36 UTC
this bug is fixed by the -9 release

Comment 6 Ben Cotton 2019-08-13 17:10:20 UTC
This bug appears to have been reported against 'rawhide' during the Fedora 31 development cycle.
Changing version to 31.

Comment 7 Ben Cotton 2019-08-13 17:11:48 UTC
This bug appears to have been reported against 'rawhide' during the Fedora 31 development cycle.
Changing version to '31'.

Comment 8 Fedora Update System 2019-08-13 19:49:08 UTC
FEDORA-2019-c8270fe288 has been submitted as an update to Fedora 30. https://bodhi.fedoraproject.org/updates/FEDORA-2019-c8270fe288

Comment 9 Fedora Update System 2019-08-14 01:36:35 UTC
dnsmasq-2.80-9.fc30 has been pushed to the Fedora 30 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-2019-c8270fe288

Comment 10 Fedora Update System 2019-08-22 01:17:20 UTC
dnsmasq-2.80-9.fc30 has been pushed to the Fedora 30 stable repository. If problems still persist, please make note of it in this bug report.