When QEMU uid/gid is set to non-root this is pointless as if we just
used a regular setuid/setgid call, the process will have all its
capabilities cleared anyway by the kernel.
When QEMU uid/gid is set to root, this is almost (always?) never
what people actually want. People make QEMU run as root in order
to access some privileged resource that libvirt doesn't support
yet and this often requires capabilities. As a result they have
to go find the qemu.conf param to turn this off. This is not
viable for libguestfs - they want to control everything via the
XML security label to request running as root regardless of the
qemu.conf settings for user/group.
Clearing capabilities was implemented originally because there
was a proposal in Fedora to change permissions such that root,
with no capabilities would not be able to compromise the system.
ie a locked down root account. This never went anywhere though,
and as a result clearing capabilities when running as root does
not really get us any security benefit AFAICT. The root user
can easily do something like create a cronjob, which will then
faithfully be run with full capabilities, trivially bypassing
the restriction we place.
IOW, our clearing of capabilities is both useless from a security
POV, and breaks valid use cases when people need to run as root.
This removes the clear_emulator_capabilities configuration
option from qemu.conf, and always runs QEMU with capabilities
when root. The behaviour when non-root is unchanged.
Reviewed-by: Cole Robinson <crobinso@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
A slirp helper is a process that provides user-mode networking through
a unix domain socket. It is expected to follow the following
specification:
https://gitlab.freedesktop.org/slirp/libslirp-rs/blob/master/src/bin/README.rst
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Some VM configurations may result in a large number of threads created by
the associated qemu process which can exceed the system default limit. The
maximum number of threads allowed per process is controlled by the pids
cgroup controller and is set to 16k when creating VMs with systemd's
machined service. The maximum number of threads per process is recorded
in the pids.max file under the machine's pids controller cgroup hierarchy,
e.g.
$cgrp-mnt/pids/machine.slice/machine-qemu\\x2d1\\x2dtest.scope/pids.max
Maximum threads per process is controlled with the TasksMax property of
the systemd scope for the machine. This patch adds an option to qemu.conf
which can be used to override the maximum number of threads allowed per
qemu process. If the value of option is greater than zero, it will be set
in the TasksMax property of the machine's scope after creating the machine.
Signed-off-by: Jim Fehlig <jfehlig@suse.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
This reverts commit fc3990c7e6.
Now that all the reported bugs are fixed let's turn the feature
back on.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Cole Robinson <crobinso@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
In cases when e.g. a new feature breaks upstream behaviour it's useful
to allow users to disable the new feature to verify the regression and
possibly use it as a workaround until a fix is available.
The new qemu.conf option named "capability_filters" allows to remove
qemu capabilities from the detected bitmap.
This patch introduces the configuration infrastructure to parse the
option and pass it around.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Add an option that lets the user specify the secret
that unlocks the server TLS key.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Turns out, that there are few bugs that are not that trivial to
fix (e.g. around block jobs). Instead of rushing in not
thoroughly tested fixes disable the feature temporarily for the
release.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
ACKed-by: Peter Krempa <pkrempa@redhat.com>
Turns out, there are couple of bugs that prevent this feature
from being operational. Given how close to the release we are
disable the feature temporarily. Hopefully, it can be enabled
back after all the bugs are fixed.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Jiri Denemark <jdenemar@redhat.com>
This config option allows users to set and enable lock manager
for domain metadata. The lock manager is going to be used by
security drivers to serialize each other when changing a file
ownership or changing the SELinux label. The only supported lock
manager is 'lockd' for now.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Extend qemu_conf with user and group for running the tpm-emulator
and add directories to the configuration for the locations of the
log, state, and socket of the tpm-emulator.
Also add these new directories to the QEMU Makefile.inc.am and
the RPM spec file libvirt.spec.in.
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Just like we allow users overriding path to bridge-helper
detected at compile time we can allow them to override path to
qemu-pr-helper.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
This reverts commit 038eb472a0.
On reflection adding defaults for arbitrary guest XML device config
settings to the qemu.conf is not a sustainable path. Removing the
support for rx/tx queue size so that it doesn't set a bad precedent.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
In 2074ef6cd4 and c56cdf259 (and friends) we've added two
attributes to virtio NICs: rx_queue_size and tx_queue_size.
However, sysadmins might want to set these on per-host basis but
don't necessarily have an access to domain XML (e.g. because they
are generated by some other app). So let's expose them under
qemu.conf (the settings from domain XML still take precedence as
they are more specific ones).
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Add a new TLS X.509 certificate type - "vxhs". This will handle the
creation of a TLS certificate capability for properly configured
VxHS network block device clients.
The following describes the behavior of TLS for VxHS block device:
(1) Two new options have been added in /etc/libvirt/qemu.conf
to control TLS behavior with VxHS block devices
"vxhs_tls" and "vxhs_tls_x509_cert_dir".
(2) Setting "vxhs_tls=1" in /etc/libvirt/qemu.conf will enable
TLS for VxHS block devices.
(3) "vxhs_tls_x509_cert_dir" can be set to the full path where the
TLS CA certificate and the client certificate and keys are saved.
If this value is missing, the "default_tls_x509_cert_dir" will be
used instead. If the environment is not configured properly the
authentication to the VxHS server will fail.
Signed-off-by: Ashish Mittal <Ashish.Mittal@veritas.com>
Signed-off-by: John Ferlan <jferlan@redhat.com>
Add a new TLS X.509 certificate type - "migrate". This will handle the
creation of a TLS certificate capability (and possibly repository) to
be used for migrations. Similar to chardev's, credentials will be handled
via a libvirt secrets; however, unlike chardev's enablement and usage
will be via a CLI flag instead of a conf flag and a domain XML attribute.
The migrations using the *x509_verify flag require the client-cert.pem
and client-key.pem files to be present in the TLS directory - so let's
also be sure to note that in the qemu.conf file.
Signed-off-by: John Ferlan <jferlan@redhat.com>
Add new parameter memory_backing_dir where files will be stored when memoryBacking
source is selected as file.
Value is stored inside char* memoryBackingDir
Given how intrusive previous patches are, it might happen that
there's a bug or imperfection. Lets give users a way out: if they
set 'namespaces' to an empty array in qemu.conf the feature is
suppressed.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
This helps in selecting log level of the gluster gfapi, output to stderr.
The option is 'gluster_debug_level', can be tuned by editing
'/etc/libvirt/qemu.conf'
Debug levels ranges 0-9, with 9 being the most verbose, and 0
representing no debugging output. The default is the same as it was
before, which is a level of 4. The current logging levels defined in
the gluster gfapi are:
0 - None
1 - Emergency
2 - Alert
3 - Critical
4 - Error
5 - Warning
6 - Notice
7 - Info
8 - Debug
9 - Trace
Signed-off-by: Prasanna Kumar Kalever <prasanna.kalever@redhat.com>
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Add a new qemu.conf variables to store the UUID for the secret that could
be used to present credentials to access the TLS chardev. Since this will
be a server level and it's possible to use some sort of default, introduce
both the default and chardev logic at the same time making the setting of
the chardev check for it's own value, then if not present checking whether
the default value had been set.
Signed-off-by: John Ferlan <jferlan@redhat.com>
Add a new TLS X.509 certificate type - "chardev". This will handle the
creation of a TLS certificate capability (and possibly repository) for
properly configured character device TCP backends.
Unlike the vnc and spice there is no "listen" or "passwd" associated. The
credentials eventually will be handled via a libvirt secret provided to
a specific backend.
Make use of the default verify option as well.
Signed-off-by: John Ferlan <jferlan@redhat.com>
Rather than specify perhaps multiple TLS X.509 certificate directories,
let's create a "default" directory which can then be used if the service
(e.g. for now vnc and spice) does not supply a default directory.
Since the default for vnc and spice may have existed before without being
supplied, the default check will first check if the service specific path
exists and if so, set the cfg entry to that; otherwise, the default will
be set to the (now) new defaultTLSx509certdir.
Additionally add a "default_tls_x509_verify" entry which can also be used
to force the peer verification option (for vnc it's a x509verify option).
Add/alter the macro for the option being found in the config file to accept
the default value.
Signed-off-by: John Ferlan <jferlan@redhat.com>
We already have the ability to turn off dumping of guest
RAM via the domain XML. This is not particularly useful
though, as it is under control of the management application.
What is needed is a way for the sysadmin to turn off guest
RAM defaults globally, regardless of whether the mgmt app
provides its own way to set this in the domain XML.
So this adds a 'dump_guest_core' option in /etc/libvirt/qemu.conf
which defaults to false. ie guest RAM will never be included in
the QEMU core dumps by default. This default is different from
historical practice, but is considered to be more suitable as
a default because
a) guest RAM can be huge and so inflicts a DOS on the host
I/O subsystem when dumping core for QEMU crashes
b) guest RAM can contain alot of sensitive data belonging
to the VM owner. This should not generally be copied
around inside QEMU core dumps submitted to vendors for
debugging
c) guest RAM contents are rarely useful in diagnosing
QEMU crashes
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Currently the QEMU processes inherit their core dump rlimit
from libvirtd, which is really suboptimal. This change allows
their limit to be directly controlled from qemu.conf instead.
Currently the QEMU stdout/stderr streams are written directly to
a regular file (eg /var/log/libvirt/qemu/$GUEST.log). While those
can be rotated by logrotate (using copytruncate option) this is
not very efficient. It also leaves open a window of opportunity
for a compromised/broken QEMU to DOS the host filesystem by
writing lots of text to stdout/stderr.
This makes it possible to connect the stdout/stderr file handles
to a pipe that is provided by virtlogd. The virtlogd daemon will
read from this pipe and write data to the log file, performing
file rotation whenever a pre-determined size limit is reached.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
When using split UEFI image, it may come handy if libvirt manages per
domain _VARS file automatically. While the _CODE file is RO and can be
shared among multiple domains, you certainly don't want to do that on
the _VARS file. This latter one needs to be per domain. So at the
domain startup process, if it's determined that domain needs _VARS
file it's copied from this master _VARS file. The location of the
master file is configurable in qemu.conf.
Temporary, on per domain basis the location of master NVRAM file can
be overridden by this @template attribute I'm inventing to the
<nvram/> element. All it does is holding path to the master NVRAM file
from which local copy is created. If that's the case, the map in
qemu.conf is not consulted.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Acked-by: Laszlo Ersek <lersek@redhat.com>
For now, we set the migration URI via command line '--migrate_uri' or
construct the URI by looking up the dest host's hostname which could be
solved by DNS automatically.
But in cases the dest host have two or more NICs to reach, we may need to
send the migration data over a specific NIC which is different from the
automatically resolved one for some reason like performance, security, etc.
Thus we must explicitly specify the migrateuri in command line everytime,
but it is too troublesome if there are many such hosts (and don't forget
virt-manager).
This patch adds a configuration file option on dest host to save the
default value set which can be specified to a migration hostname or
one of this host's addresses used for transferring data, thus user doesn't
have to specify it in command line everytime.
Signed-off-by: Chen Fan <chen.fan.fnst@cn.fujitsu.com>
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
QEMU commit 5e2ac51 added a boolean '-msg timestamp=[on|off]'
option, which can enable timestamps on errors:
$ qemu-system-x86_64 -msg timestamp=on zghhdorf
2014-04-09T13:25:46.779484Z qemu-system-x86_64: -msg timestamp=on: could
not open disk image zghhdorf: Could not open 'zghhdorf': No such file or
directory
Enable this timestamp if the QEMU binary supports it.
Add a 'log_timestamp' option to qemu.conf for disabling this behavior.
Commit e3ef20d7 allows user to configure migration ports range via
qemu.conf. However, it forgot to update augeas definition file and
even the test data was malicious.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
QEMU has support for SASL auth for SPICE guests, but libvirt
has no way to enable it. Following the example from VNC where
it is globally enabled via qemu.conf
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The regular save image code has the support to compress images using a
specified algorithm. This was not implemented for external checkpoints
although it shares most of the backend code.
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1017227
This configuration knob is there to override default listen address for
-incoming for all qemu domains.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
On my machine, a guest fails to boot if it has a sound card, but not
graphical device/display is configured, because pulseaudio fails to
initialize since it can't access $HOME.
A workaround is removing the audio device, however on ARM boards there
isn't any option to do that, so -nographic always fails.
Set QEMU_AUDIO_DRV=none if no <graphics> are configured. Unfortunately
this has massive test suite fallout.
Add a qemu.conf parameter nographics_allow_host_audio, that if enabled
will pass through QEMU_AUDIO_DRV from sysconfig (similar to
vnc_allow_host_audio)
Adding a VNC WebSocket support for QEMU driver. This functionality is
in upstream qemu from commit described as v1.3.0-982-g7536ee4, so the
capability is being recognized based on QEMU version for now.
The defines QEMU_REMOTE_PORT_MIN and QEMU_REMOTE_PORT_MAX were used to
find free port when starting domains. As this was hard-coded to the
same ports as default VNC servers, there were races with these other
programs. This patch includes the possibility to change the default
starting port as well as the maximum port (mostly for completeness) in
qemu config file.
Support for two new config options in qemu.conf is added:
- remote_port_min (defaults to QEMU_REMOTE_PORT_MIN and
must be >= than this value)
- remote_port_max (defaults to QEMU_REMOTE_PORT_MAX and
must be <= than this value)
Currently all the config options are listed under a 'vnc_entry'
group. Create a bunch of new groups & move options to the
right place
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Add nmissing 'host_uuid' entry to libvirtd.conf lens and
rename spice_passwd to spice_password in qemu.conf lens
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
If vdsm is installed and configured in Fedora 17, we add the following
items into qemu.conf:
spice_tls=1
spice_tls_x509_cert_dir="/etc/pki/vdsm/libvirt-spice"
However, after this changes, augtool cannot identify qemu.conf anymore.
Curently security labels can be of type 'dynamic' or 'static'.
If no security label is given, then 'dynamic' is assumed. The
current code takes advantage of this default, and avoids even
saving <seclabel> elements with type='dynamic' to disk. This
means if you temporarily change security driver, the guests
can all still start.
With the introduction of sVirt to LXC though, there needs to be
a new default of 'none' to allow unconfined LXC containers.
This patch introduces two new security label types
- default: the host configuration decides whether to run the
guest with type 'none' or 'dynamic' at guest start
- none: the guest will run unconfined by security policy
The 'none' label type will obviously be undesirable for some
deployments, so a new qemu.conf option allows a host admin to
mandate confined guests. It is also possible to turn off default
confinement
security_default_confined = 1|0 (default == 1)
security_require_confined = 1|0 (default == 0)
* src/conf/domain_conf.c, src/conf/domain_conf.h: Add new
seclabel types
* src/security/security_manager.c, src/security/security_manager.h:
Set default sec label types
* src/security/security_selinux.c: Handle 'none' seclabel type
* src/qemu/qemu.conf, src/qemu/qemu_conf.c, src/qemu/qemu_conf.h,
src/qemu/libvirtd_qemu.aug: New security config options
* src/qemu/qemu_driver.c: Tell security driver about default
config
This patch adds max_files option to qemu.conf which can be used to
override system default limit on number of opened files that are
allowed for qemu user.
This patch creates an optional BeginJob queue size limit. When
active, all other attempts above level will fail. To set this
feature assign desired value to max_queued variable in qemu.conf.
Setting it to 0 turns it off.
When auto-dumping a domain on crash events, or autostarting a domain
with managed save state, let the user configure whether to imply
the bypass cache flag.
* src/qemu/qemu.conf (auto_dump_bypass_cache, auto_start_bypass_cache):
Document new variables.
* src/qemu/libvirtd_qemu.aug (vnc_entry): Let augeas parse them.
* src/qemu/qemu_conf.h (qemud_driver): Store new preferences.
* src/qemu/qemu_conf.c (qemudLoadDriverConfig): Parse them.
* src/qemu/qemu_driver.c (processWatchdogEvent, qemuAutostartDomain):
Honor them.
