/usr/bin/qemu-system-x86_64 -S -no-user-config -nodefaults -nographic -machine none,accel=kvm:tcg -qmp unix:/var/lib/libvirt/qemu/capabilities.monitor.sock,server,nowait -pidfile /var/lib/libvirt/qemu/capabilities.pidfile -daemonize
libvirtd needs to be allowed to kill these processes, otherwise they
remain running.
On live migration with --p2p like:
$ virsh migrate --live --p2p kvmguest-bionic-normal \
qemu+ssh://10.6.221.80/system
We hit an apparmor deny like:
apparmor="DENIED" operation="file_inherit"
profile="/usr/sbin/libvirtd" pid=23477 comm="ssh" family="unix"
sock_type="stream" protocol=0 requested_mask="send receive"
denied_mask="send" addr=none peer_addr=none peer="unconfined"
The rule is not perfect, but can't be restricted further at the moment
(new upstream kernel features needed). For now the lack of a profile on the
peer as well as comm not being a conditional on rules do not allow to filter
further.
Signed-off-by: Christian Ehrhardt <christian.ehrhardt@canonical.com>
Commit b482925c added ptrace rule for the apparmor profiles,
but one was missed in the libvirtd profile for dnsmasq. It was
overlooked since the test machine did not have an active libvirt
network requiring dnsmasq that was also set to autostart. With
one active and set to autostart, the following denial is observed
in audit.log when restarting libvirtd
type=AVC msg=audit(1507320136.306:298): apparmor="DENIED" \
operation="ptrace" profile="/usr/sbin/libvirtd" pid=5472 \
comm="libvirtd" requested_mask="trace" denied_mask="trace" \
peer="/usr/sbin/dnsmasq"
With an active network, I suspect a libvirtd restart causes access
to /proc/<dnsmasq-pid>/*, hence the resulting denial. As a nasty
side affect of the denial, libvirtd thinks it needs to spawn a
dnsmasq process even though one is already running for the network.
E.g. after two libvirtd restarts
dnsmasq 1683 0.0 0.0 51188 2612 ? S 12:03 0:00 \
/usr/sbin/dnsmasq --conf-file=/var/lib/libvirt/dnsmasq/default.conf \
--leasefile-ro --dhcp-script=/usr/lib64/libvirt/libvirt_leaseshelper
root 1684 0.0 0.0 51160 576 ? S 12:03 0:00 \
/usr/sbin/dnsmasq --conf-file=/var/lib/libvirt/dnsmasq/default.conf \
--leasefile-ro --dhcp-script=/usr/lib64/libvirt/libvirt_leaseshelper
dnsmasq 4706 0.0 0.0 51188 2572 ? S 13:54 0:00 \
/usr/sbin/dnsmasq --conf-file=/var/lib/libvirt/dnsmasq/default.conf \
--leasefile-ro --dhcp-script=/usr/lib64/libvirt/libvirt_leaseshelper
root 4707 0.0 0.0 51160 572 ? S 13:54 0:00 \
/usr/sbin/dnsmasq --conf-file=/var/lib/libvirt/dnsmasq/default.conf \
--leasefile-ro --dhcp-script=/usr/lib64/libvirt/libvirt_leaseshelper
dnsmasq 4791 0.0 0.0 51188 2580 ? S 13:56 0:00 \
/usr/sbin/dnsmasq --conf-file=/var/lib/libvirt/dnsmasq/default.conf \
--leasefile-ro --dhcp-script=/usr/lib64/libvirt/libvirt_leaseshelper
root 4792 0.0 0.0 51160 572 ? S 13:56 0:00 \
/usr/sbin/dnsmasq --conf-file=/var/lib/libvirt/dnsmasq/default.conf \
--leasefile-ro --dhcp-script=/usr/lib64/libvirt/libvirt_leaseshelper
A simple fix is to add a ptrace rule for dnsmasq.
Signed-off-by: Jim Fehlig <jfehlig@suse.com>
Reviewed-By: Guido Günther <agx@sigxcpu.org>
On Debian/Ubuntu the libxl-save-helper (used when saving/restoring
a domain through libxl) is located under /usr/lib/xen-<version>/bin.
Bug-Ubuntu: https://bugs.launchpad.net/bugs/1334195
Signed-off-by: Christian Ehrhardt <christian.ehrhardt@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Apparmor must not prevent access to required helper programs. The following
helpers should be allowed to run in unconfined execution mode:
- libvirt_parthelper
- libvirt_iohelper
The network and nwfilter tests contained in the libvirt-TCK testkit can fail
unless access to raw network packets is granted. Without this access, the
following apparmor error can be seen while running the tests:
apparmor="DENIED" operation="create" parent=1 profile="/usr/sbin/libvirtd"
pid=94731 comm="libvirtd" family="packet" sock_type="raw" protocol=768
In order for apparmor to work properly in Xen environments, the following
access rights need to be allowed:
- Allow CAP_SYS_PACCT, which is required when resetting some multi-port
Broadcom cards by writting to the PCI config space
- Allow CAP_IPC_LOCK, which is required to lock/unlock memory. Without
this setting, an error 'Resource temporarily unavailable' can be seen
while attempting to mmap memory. At the same time, the following
apparmor message is seen:
apparmor="DENIED" operation="capable" parent=1 profile="/usr/sbin/libvirtd"
pid=2097 comm="libvirtd" pid=2097 comm="libvirtd" capability=14
capname="ipc_lock"
- Allow access to distribution specific directories:
/usr/{lib,lib64}/xen/bin
See lp#1276719 for the bug description. As virt-aa-helper doesn't know
the VFIO groups to use for the guest, allow access to all
/dev/vfio/[0-9]* and /dev/vfio/vfio files if there is a potential need
for vfio
Signed-off-by: Eric Blake <eblake@redhat.com>
* examples/apparmor/libvirt-qemu: adds pulseaudio, alsa and preliminary
save/restore to the example apparmor abstraction
* examples/apparmor/usr.sbin.libvirtd: allows libvirtd access to inet
dgram, inet6 dgram, inet6 stream and /usr/lib/libvirt/*
* docs/drvqemu.html.in: include documentation for AppArmor sVirt
confinement
* examples/apparmor/TEMPLATE examples/apparmor/libvirt-qemu
examples/apparmor/usr.lib.libvirt.virt-aa-helper
examples/apparmor/usr.sbin.libvirtd: example templates and
configuration files for SVirt Apparmor when using KVM/QEmu
