[libvirt] [PATCH] conf: Fix crash when src->hosts = NULL in virStorageFileBackendGlusterInit

https://bugzilla.redhat.com/show_bug.cgi?id=1162974 When do external snapshot for a gluster disk with no host name(ip) in snapshot xml, libvirtd will crash. Because when node do not have a children in virDomainStorageHostParse, libvirt will return 0, but donnot get hosts for virStorageFileBackendGlusterInit. snpahost.xml: <domainsnapshot> <name>snapshot_test</name> <description>Snapshot Test</description> <disks> <disk name='vda' snapshot='external' type='network'> <source protocol='gluster' name='gluster-vol1/gluster.img.snap'/> </disk> </disks> </domainsnapshot> Back trace: virsh snapshot-create r6 snapshot.xml --disk-only 0 virStorageFileBackendGlusterInit (src=0x7fc760007ca0) at storage/storage_backend_gluster.c:577 1 0x00007fc76d678e22 in virStorageFileInitAs (src=0x7fc760007ca0, uid=uid@entry=4294967295, gid=gid@entry=4294967295) at storage/storage_driver.c:2547 2 0x00007fc76d678e9c in virStorageFileInit (src=<optimized out>) at storage/storage_driver.c:2567 3 0x00007fc76bc13f9c in qemuDomainSnapshotPrepareDiskExternal (reuse=false, active=true, snapdisk=0x7fc7600019b8, disk=0x7fc7641e4880, conn=0x7fc76426cc10) at qemu/qemu_driver.c:12995 4 qemuDomainSnapshotPrepare (flags=<synthetic pointer>, def=0x7fc760002570, vm=0x7fc76422b530, conn=0x7fc76426cc10) at qemu/qemu_driver.c:13156 5 qemuDomainSnapshotCreateXML (domain=0x7fc760001f30, xmlDesc=<optimized out>, flags=16) at qemu/qemu_driver.c:13896 6 0x00007fc782d4de4d in virDomainSnapshotCreateXML (domain=domain@entry=0x7fc760001f30, xmlDesc=0x7fc760001b80 "<domainsnapshot>\n<name>snapshot_test</name>\n<description>Snapshot Test</description>\n<disks>\n<disk name='vda' snapshot='external' type='network'>\n<source protocol='gluster' name='gluster-vol1/gluster."..., flags=16) at libvirt.c:18488 7 0x00007fc7837cb44c in remoteDispatchDomainSnapshotCreateXML (server=<optimized out>, msg=<optimized out>, ret=0x7fc760000a60, args=0x7fc760001f90, rerr=0x7fc77344dc80, client=<optimized out>) at remote_dispatch.h:8605 Signed-off-by: Luyao Huang <lhuang(a)redhat.com&gt; --- src/conf/domain_conf.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c index 2c65276..34c1c12 100644 --- a/src/conf/domain_conf.c +++ b/src/conf/domain_conf.c @@ -4150,7 +4150,12 @@ virDomainStorageHostParse(xmlNodePtr node, memset(&host, 0, sizeof(host)); - child = node->children; + if ((child = node->children) == NULL) { + virReportError(VIR_ERR_XML_ERROR, "%s", + _("Can not find a host in xml")); + goto cleanup; + } + while (child != NULL) { if (child->type == XML_ELEMENT_NODE && xmlStrEqual(child->name, BAD_CAST "host")) { -- 1.8.3.1