Bug 984821
Summary: | Crash of libvirtd without guest agent configuration | ||
---|---|---|---|
Product: | Red Hat Enterprise Linux 6 | Reporter: | Alex Jia <ajia> |
Component: | libvirt | Assignee: | Alex Jia <ajia> |
Status: | CLOSED ERRATA | QA Contact: | Virtualization Bugs <virt-bugs> |
Severity: | high | Docs Contact: | |
Priority: | high | ||
Version: | 6.5 | CC: | acathrow, dyuan, eblake, herrold, jdenemar, jmiao, pkrempa, weizhan |
Target Milestone: | rc | ||
Target Release: | --- | ||
Hardware: | x86_64 | ||
OS: | Linux | ||
Whiteboard: | |||
Fixed In Version: | libvirt-0.10.2-21.el6 | Doc Type: | Bug Fix |
Doc Text: | Story Points: | --- | |
Clone Of: | Environment: | ||
Last Closed: | 2013-11-21 09:07:04 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: | 986383, 986386 |
Description
Alex Jia
2013-07-16 06:28:43 UTC
Path on upstream: https://www.redhat.com/archives/libvir-list/2013-July/msg00980.html Fix upstream in v1.1.0-199-g96518d4 with: commit 96518d4316b711c72205117f8d5c967d5127bbb6 Author: Alex Jia <ajia> Date: Tue Jul 16 17:30:20 2013 +0800 qemu: Prevent crash of libvirtd without guest agent configuration If users haven't configured guest agent then qemuAgentCommand() will dereference a NULL 'mon' pointer, which causes crash of libvirtd when using agent based cpu (un)plug. With the patch, when the qemu-ga service isn't running in the guest, a expected error "error: Guest agent is not responding: Guest agent not available for now" will be raised, and the error "error: argument unsupported: QEMU guest agent is not configured" is raised when the guest hasn't configured guest agent. GDB backtrace: (gdb) bt #0 virNetServerFatalSignal (sig=11, siginfo=<value optimized out>, context=<value optimized out>) at rpc/virnetserver.c:326 #1 <signal handler called> #2 qemuAgentCommand (mon=0x0, cmd=0x7f39300017b0, reply=0x7f394b090910, seconds=-2) at qemu/qemu_agent.c:975 #3 0x00007f39429507f6 in qemuAgentGetVCPUs (mon=0x0, info=0x7f394b0909b8) at qemu/qemu_agent.c:1475 #4 0x00007f39429d9857 in qemuDomainGetVcpusFlags (dom=<value optimized out>, flags=9) at qemu/qemu_driver.c:4849 #5 0x00007f3957dffd8d in virDomainGetVcpusFlags (domain=0x7f39300009c0, flags=8) at libvirt.c:9843 How to reproduce? # To start a guest without guest agent configuration # then run the following cmdline # virsh vcpucount foobar --guest error: End of file while reading data: Input/output error error: One or more references were leaked after disconnect from the hypervisor error: Failed to reconnect to the hypervisor RHBZ: https://bugzilla.redhat.com/show_bug.cgi?id=984821 Signed-off-by: Alex Jia <ajia> Signed-off-by: Peter Krempa <pkrempa> While testing the patch above I also found another bug in this section of code that also crashes the daemon. This issue is fixed upstream with: commit dfc692350a04a70b4ca65667c30869b3bfdaf034 Author: Peter Krempa <pkrempa> Date: Tue Jul 16 15:39:06 2013 +0200 qemu: Fix double free of returned JSON array in qemuAgentGetVCPUs() A part of the returned monitor response was freed twice and caused crashes of the daemon when using guest agent cpu count retrieval. # virsh vcpucount dom --guest Introduced in v1.0.6-48-gc6afcb0 v1.1.0-208-gdfc6923 1. # rpm -q libvirt libvirt-0.10.2-21.el6.x86_64 2. no guest-agnet configuration # virsh dumpxml r6 | grep agent 3. start # virsh start r6 Domain r6 started 4. vcpucount # virsh vcpucount r6 --guest error: argument unsupported: QEMU guest agent is not configured No crash happened, so change the status to VERIFIED. 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, and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. http://rhn.redhat.com/errata/RHBA-2013-1581.html |