In the past we had to declare @cfg and then explicitly unref it.
But now, with glib we can use g_autoptr() which will do the unref
automatically and thus is more bulletproof.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Laine Stump <laine@redhat.com>
In the qemuInterfacePrepareSlirp() function, the qemu driver
config is obtained (via virQEMUDriverGetConfig()), but it is
never unrefed leading to mangled refcounter.
Fixes: 9145b3f1cc
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Laine Stump <laine@redhat.com>
In 6.7.0 release I've changed how domain namespace is built and
populated. Previously it used to be done from a pre-exec hook
(ran in the forked off child, just before dropping all privileges
and exec()-ing QEMU), which not only meant we had to have two
different code paths for creating a node in domain's namespace
(one for this pre-exec hook, the other for hotplug ran from the
daemon), it also proved problematic because it was leaking FDs
into QEMU process.
To mitigate this problem, we've not only ditched libdevmapper
from the NS population process, I've also dropped the pre-exec
code and let the NS be populated from the daemon (using the
hotplug code). But, I was not careful when doing so, because the
pre-exec code was tolerant to files that doesn't exist, while
this new code isn't. For instance, the very first thing that is
done when the new NS is created is it's populated with
@defaultDeviceACL which contain files like /dev/null, /dev/zero,
/dev/random and /dev/kvm (and others). While the rest will
probably exist every time, /dev/kvm might not and thus the new
code I wrote has to be tolerant to that.
Of course, users can override the @defaultDeviceACL (by setting
cgroup_device_acl in qemu.conf) and remove /dev/kvm (which is
acceptable workaround), but we definitely want libvirt to work
out of the box even on hosts without KVM.
Fixes: 9048dc4e62
Reported-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
As it turned out my previous commits which switched from HAVE_ to
WITH_ and dropped stdarg.h detection were a bit too aggressive.
Because of reasons described in 9ea3424a17 we need to define
HAVE_STDARG_H before including readline otherwise macos build
fails. Honestly, I still don't fully understand the problem so I
am not going to bother you with "explanation".
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
This allows us to drop include of readline header files from
virsh.c and virt-admin.c because they needed it only because of
the add_history() function.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Currently, we are mixing: #if HAVE_BLAH with #if WITH_BLAH.
Things got way better with Pavel's work on meson, but apparently,
mixing these two lead to confusing and easy to miss bugs (see
31fb929eca for instance). While we were forced to use HAVE_
prefix with autotools, we are free to chose our own prefix with
meson and since WITH_ prefix appears to be more popular let's use
it everywhere.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
In packet-libvirt.c in wireshark dissector we include rpc/types.h
but guard the include with a condition (that is supposed to be
true if we detected during configure phase that the host system
has the header file). Thing is, it looks like we were never doing
the configure check and thus the file was never included and yet,
the NSS plugin works. Drop the include then.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
In meson.build, we check for presence of unshare() function
explicitly (even though there is the function usability check a
few hundred lines below), but never have any code depending on
HAVE_UNSHARE. The same applies to stdarg.h and sys/sysctl.h
header files - either we simply include them or guard their
include using different conditionals.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
There are couple of conditional #includes at the beginning of
virfile.c and they try to be nice and document #endifs. But they
are mostly wrong because either they have the condition in the
comment inverted or the comment refers to a different condition
than they belong to. Just remove the comments as these #includes
are single line mostly.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
There are two places where we try to check whether the host
system has net/if.h before including it. But the check is missing
'_H' suffix.
Fixes: 7f3eb533f4
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
When switching to meson, some of HAVE_* macros were renamed to
WITH_ because they did not reflect whether the build platform has
or doesn't have something, but whether we are building with some
functionality turned on or off. This is the case with
HAVE_BSD_NSS macro too. As a result, the NSS plugin built on BSD
did not expose nss_module_register() function which made the
plugin unusable:
https://www.redhat.com/archives/libvir-list/2020-September/msg00000.html
Fixes: c742687055
Reported-by: Roman Bogorodskiy <bogorodskiy@gmail.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Roman Bogorodskiy <bogorodskiy@gmail.com>
Reviewed-by: Jiri Denemark <jdenemar@redhat.com>
When editing a domain with hotplug enabled, I removed the only
NUMA node it had and got no error. I got the error later though,
when starting the domain. This is not as user friendly as it can
be. Move the validation call out from command line generator and
into domain validator (which is called prior to starting cmd line
generation anyway).
When doing this, I had to remove memory-hotplug-nonuma xml2xml
test case because there is no way the test case can succeed,
obviously.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
So far, the <cell/> element can have two types of children
elements: <distances/> and <cache/> (which can be repeated more
times). However, there is no reason to require specific order in
input XML. Allow elements to be interleaved.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Even if namespaces are disabled, then due to a missing check at the
beginning of qemuDomainBuildNamespace(), the domain startup code
still tries to populate (nonexistent) domain's namespace.
Fixes: 8da362fe62
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Jiri Denemark <jdenemar@redhat.com>
This function is not changing the domain definition, it's only
reading from it. The function is going to be used from another
function which already takes const virDomainDef. Make the @def
const to avoid typecasting it.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
This is similar to one of previous patches.
When receiving stream (on virStorageVolUpload() and subsequent
virStreamSparseSendAll()) we may receive a hole. If the volume we
are saving the incoming data into is a regular file we just
lseek() and ftruncate() to create the hole. But this won't work
if the file is a block device. If that is the case we must write
zeroes so that any subsequent reader reads nothing just zeroes
(just like they would from a hole in a regular file).
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1852528
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
This is very similar to previous commit.
The virshStreamInData() callback is used by virStreamSparseSendAll()
to detect whether the file the data is read from is in data or hole
section. The SendAll() will then send corresponding type of virStream
message to make server create a hole or write actual data. But the
callback uses virFileInData() even for block devices, which results in
an error. Just like in previous commit, emulate a DATA section
for block devices.
Partially resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1852528
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
When handling sparse stream, a thread is executed. This thread
runs a read() or write() loop (depending what API is called; in
this case it's virStorageVolDownload() and this the thread run
read() loop). The read() is handled in virFDStreamThreadDoRead()
which is then data/hole section aware, meaning it uses
virFileInData() to detect data and hole sections and sends
TYPE_DATA or TYPE_HOLE virStream messages accordingly.
However, virFileInData() does not work with block devices. Simply
because block devices don't have data and hole sections. What we
can do though, is to mimic being always in a DATA section.
Partially resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1852528
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
This callback is called when the server sends us STREAM_HOLE
meaning there is no real data, only zeroes. For regular files
we would just seek() beyond EOF and ftruncate() to create the
hole. But for block devices this won't work. Not only we can't
seek() beyond EOF, and ftruncate() will fail, this approach won't
fill the device with zeroes. We have to do it manually.
Partially resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1852528
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
We can't use virFileInData() with block devices, but we can
emulate being in data section all the time (vol-upload case).
Alternatively, we can't just lseek() beyond EOF with block
devices to create a hole, we will have to write zeroes
(vol-download case). But to decide we need to know if the FD we
are reading data from / writing data to is a block device. Store
this information in _virshStreamCallbackData.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
These callback will need to know more that the FD they are
working on. Pass the structure that is passed to other stream
callbacks (e.g. virshStreamSource() or virshStreamSourceSkip())
instead of inventing a new one.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
For libvirt, the volume is just a binary blob and it doesn't
interpret data on volume upload/download. But as it turns out,
this unspoken assumption is not clear to our users. Document it
explicitly.
Suggested in: https://bugzilla.redhat.com/show_bug.cgi?id=1851023#c17
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
In a very distant past, we came around machines that has not
continuous node IDs. This made us error out when constructing
capabilities XML. We resolved it by utilizing strange behaviour
of numa_node_to_cpus() in which it returned a mask with all bits
set for a non-existent node. However, this is not the only case
when it returns all ones mask - if the node exists and has enough
CPUs to fill the mask up (e.g. 128 CPUs).
The fix consists of using nodemask_isset(&numa_all_nodes, ..)
prior to calling numa_node_to_cpus() to determine if the node
exists.
Fixes: 628c935747
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1860231
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
After previous cleanups, some labels in some functions have
nothing but 'return' statement in them. Drop the labels and
replace 'goto'-s with respective return statements.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
Again, instead of closing FDs explicitly, we can automatically
close them when they go out of their respective scopes.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
A cleanup function can be declared for virFDStreamMsg type so
that the structure doesn't have to be freed explicitly.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
All callers of virFDStreamMsgQueuePush() have the same pattern:
they explicitly set @msg passed to NULL to avoid freeing it later
on. Well, the function can take address of the pointer and clear
it for them.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
The buffer that allocated in the virFDStreamThreadDoRead() can be
automatically freed, or if saved into the message structure it
can be stolen.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
So far, only ENOENT is ignored (to deal with kernels without
devmapper). However, as reported on the list, under certain
scenarios a different error can occur. For instance, when libvirt
is running inside a container which doesn't have permissions to
talk to the devmapper. If this is the case, then open() returns
-1 and sets errno=EPERM.
Assuming that multipath devices are fairly narrow use case and
using them in a restricted container is even more narrow the best
fix seems to be to ignore all open errors BUT produce a warning
on failure. To avoid flooding logs with warnings on kernels
without devmapper the level is reduced to a plain debug message.
Reported-by: Christian Ehrhardt <christian.ehrhardt@canonical.com>
Reviewed-by: Christian Ehrhardt <christian.ehrhardt@canonical.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
When adding support for HMAT, in f0611fe883 I've introduced a
check which aims to validate /domain/cpu/numa/interconnects. As a
part of that, there is a loop which checks whether all <latency/>
with @cache attribute refer to an existing cache level. For
instance:
<cpu mode='host-model' check='partial'>
<numa>
<cell id='0' cpus='0-5' memory='512000' unit='KiB' discard='yes'>
<cache level='1' associativity='direct' policy='writeback'>
<size value='8' unit='KiB'/>
<line value='5' unit='B'/>
</cache>
</cell>
<interconnects>
<latency initiator='0' target='0' cache='1' type='access' value='5'/>
<bandwidth initiator='0' target='0' type='access' value='204800' unit='KiB'/>
</interconnects>
</numa>
</cpu>
This XML defines that accessing L1 cache of node #0 from node #0
has latency of 5ns.
However, the loop was not written properly. Well, the check in
it, as it was always checking for the first cache in the target
node and not the rest. Therefore, the following example errors
out:
<cpu mode='host-model' check='partial'>
<numa>
<cell id='0' cpus='0-5' memory='512000' unit='KiB' discard='yes'>
<cache level='3' associativity='direct' policy='writeback'>
<size value='10' unit='KiB'/>
<line value='8' unit='B'/>
</cache>
<cache level='1' associativity='direct' policy='writeback'>
<size value='8' unit='KiB'/>
<line value='5' unit='B'/>
</cache>
</cell>
<interconnects>
<latency initiator='0' target='0' cache='1' type='access' value='5'/>
<bandwidth initiator='0' target='0' type='access' value='204800' unit='KiB'/>
</interconnects>
</numa>
</cpu>
This errors out even though it is a valid configuration. The L1
cache under node #0 is still present.
Fixes: f0611fe883
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Laine Stump <laine@redhat.com>
In one of my latest patch (v6.6.0~30) I was trying to remove
libdevmapper use in favor of our own implementation. However, the
code did not take into account that device mapper can be not
compiled into the kernel (e.g. be a separate module that's not
loaded) in which case /proc/devices won't have the device-mapper
major number and thus virDevMapperGetTargets() and/or
virIsDevMapperDevice() fails.
However, such failure is safe to ignore, because if device mapper
is missing then there can't be any multipath devices and thus we
don't need to allow the deps in CGroups, nor create them in the
domain private namespace, etc.
Fixes: 2249455654
Reported-by: Andrea Bolognani <abologna@redhat.com>
Reported-by: Christian Ehrhardt <christian.ehrhardt@canonical.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Christian Ehrhardt <christian.ehrhardt@canonical.com>
Tested-by: Christian Ehrhardt <christian.ehrhardt@canonical.com>
The device mapper major is needed in virIsDevMapperDevice() which
determines whether given device is managed by device-mapper. This
number is obtained by parsing /proc/devices and then stored in a
global variable so that the file doesn't have to be parsed again.
However, as it turns out this logic is flawed - the major number
is not static and can change as it can be specified as a
parameter when loading the dm-mod module.
Unfortunately, I was not able to come up with a good solution and
thus the /proc/devices file is being parsed every time we need
the device mapper major.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Christian Ehrhardt <christian.ehrhardt@canonical.com>
Tested-by: Christian Ehrhardt <christian.ehrhardt@canonical.com>
We can use qemuDomainSetupInput() to obtain the path that we
need to unlink() from within domain's namespace.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
We can use qemuDomainSetupRNG() to obtain the path that we
need to unlink() from within domain's namespace.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
We can use qemuDomainSetupChardev() to obtain the path that we
need to unlink() from within domain's namespace. Note, while
previously we unlinked only VIR_DOMAIN_CHR_TYPE_DEV chardevs,
with this change we unlink some other types too - exactly those
types we created when plugging the device in.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
We can use qemuDomainSetupMemory() to obtain the path that we
need to unlink() from within domain's namespace.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
In my attempt to deduplicate the code, we can use
qemuDomainSetupHostdev() to obtain the list of paths to unlink
and then pass it to qemuDomainNamespaceUnlinkPaths() to unlink
them in a single fork.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
So far, the only caller qemuDomainNamespaceUnlinkPath() will
always pass a single path to unlink, but similarly to
qemuDomainNamespaceMknodPaths() - there are a few callers that
would like to pass two or more files to unlink at once (held in a
string list). Make the @paths argument a string list then.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Simirarly to qemuDomainAttachDeviceMknodHelper() which was
modified just a couple of commits ago, modify the unlink helper
which is called on device detach so that it can unlink multiple
files in one go instead of forking off for every single one of
them.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
After previous cleanup, creating /dev nodes from pre-exec hook is
no longer needed and thus can be removed.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
As mentioned in one of previous commits, populating domain's
namespace from pre-exec() hook is dangerous. This commit moves
population of the namespace with domain SEV into daemon's
namespace.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
As mentioned in one of previous commits, populating domain's
namespace from pre-exec() hook is dangerous. This commit moves
population of the namespace with domain loader into daemon's
namespace.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
As mentioned in one of previous commits, populating domain's
namespace from pre-exec() hook is dangerous. This commit moves
population of the namespace with domain RNGs into daemon's
namespace.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
As mentioned in one of previous commits, populating domain's
namespace from pre-exec() hook is dangerous. This commit moves
population of the namespace with domain inputs into daemon's
namespace.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
As mentioned in one of previous commits, populating domain's
namespace from pre-exec() hook is dangerous. This commit moves
population of the namespace with domain graphics (render node)
into daemon's namespace.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
As mentioned in one of previous commits, populating domain's
namespace from pre-exec() hook is dangerous. This commit moves
population of the namespace with domain TPM into daemon's
namespace.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
As mentioned in one of previous commits, populating domain's
namespace from pre-exec() hook is dangerous. This commit moves
population of the namespace with domain chardevs into daemon's
namespace.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
As mentioned in one of previous commits, populating domain's
namespace from pre-exec() hook is dangerous. This commit moves
population of the namespace with domain memory (nvdimms) into
daemon's namespace.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
As mentioned in one of previous commits, populating domain's
namespace from pre-exec() hook is dangerous. This commit moves
population of the namespace with domain hostdevs into daemon's
namespace.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
As mentioned in one of previous commits, populating domain's
namespace from pre-exec() hook is dangerous. This commit moves
population of the namespace with domain disks into daemon's
namespace.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
As mentioned in previous commit, populating domain's namespace
from pre-exec() hook is dangerous. This commit moves population
of the namespace with basic /dev nodes (e.g. /dev/null, /dev/kvm,
etc.) into daemon's namespace.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Okay, here is the deal. Currently, the way we build namespace is
very fragile. It is done from pre-exec hook when starting a
domain, after we mass closed all FDs and before we drop
privileges and exec() QEMU. This fact poses some limitations onto
the namespace build code, e.g. it has to make sure not to keep
any FD opened (not even through a library call), because it would
be leaked to QEMU. Also, it has to call only async signal safe
functions. These requirements are hard to meet - in fact as of my
commit v6.2.0-rc1~235 we are leaking a FD into QEMU by calling
libdevmapper functions.
To solve this issue and avoid similar problems in the future, we
should change our paradigm. We already have functions which can
populate domain's namespace with nodes from the daemon context.
If we use them to populate the namespace and keep only the bare
minimum in the pre-exec hook, we've mitigated the risk.
Therefore, the old qemuDomainBuildNamespace() is renamed to
qemuDomainUnshareNamespace() and new qemuDomainBuildNamespace()
function is introduced. So far, the new function is basically a
NOP and domain's namespace is still populated from the pre-exec
hook - next patches will fix it.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
The aim to make it look as close to
qemuDomainNamespaceSetupDisk() as possible. The latter will call
the former and this change makes that diff easier to read.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Every caller does the same - counts the number of items in a
string list they have, only to pass the number to
qemuDomainNamespaceMknodPaths(). This is needless - the function
can accept the string list and count the items itself.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
While the previous commit prepared the helper function run in a
forked off helper (with corresponding struct), this commit
modifies the caller, which now create all files requested in a
single process and does not fork off for every single path.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
So far, when attaching a device needs two or more /dev nodes
created into a domain, we fork off and run the helper for every
node separately. For majority of devices this is okay, because
they need no or one node created anyway. But the idea is to use
this attach code to build the namespace when starting a domain,
in which case there will be way more nodes than one.
To achieve this, the recursive approach for handling symlinks has
to be turned into an iterative one.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
When attaching a device into a domain, the corresponding /dev
node might need to be created in the domain's namespace. For some
types of files we call mknod(), for symlinks we call symlink(),
but for others - which exist in the host namespace - we need to
so called 'bind mount' them (which is a way of passing a
file/directory between mount namespaces). There is this condition
in qemuDomainAttachDeviceMknodRecursive() which decides whether a
bind mount will be used, move it into a separate function so that
it can be reused later.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
This structure is going to be used from not only device attach
code, but also when building the namespace. Moreover, the code
lives in a separate file so the chances of clashing with another
name are minimal.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
It's not really a problem since this is a helper process that
dies as soon as the helper function returns, but the cleanup code
will be replaced with a function soon and this change prepares
the code for that.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
While qemuDomainNamespaceMknodPaths() doesn't actually create
files in the namespace in one go (it forks for each path), it a
few commits time it will.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Functions that create a device node after domain startup (used
from hotplug) will get a list of paths they want to create and
eventually call qemuDomainNamespaceMknodPaths() which then checks
whether domain mount namespace is enabled in the first place.
Alternatively, on device hotunplug, we might want to delete a
path inside domain namespace in which case
qemuDomainNamespaceUnlinkPaths() checks whether the namespace is
enabled. While this is not dangerous, it certainly burns a couple
of CPU cycles needlessly.
Check whether mount namespace is enabled upfront.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
There is a lot of functions called from
qemuDomainBuildNamespace() that accept @cfg
(virQEMUDriverConfigPtr) as an argument and don't use it.
Historically, it was done so that all qemuDomainSetupAll*()
functions look the same.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
The name of this function is not very helpful, because it doesn't
create anything, it just flips a bit in a bitmask when domain is
starting up. Move the function internals into qemu_process.c and
forget the function ever existed.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
The qemu_domain.c file is big as is and we should split it into
separate semantic blocks. Start with code that handles domain
namespaces.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
In contrast with other releases, this time NEWS is pretty much
updated. I've identified only a couple of features/bug fixes
worth mentioning that were not mentioned yet.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Andrea Bolognani <abologna@redhat.com>
Document the fix of leaking /dev/mapper/control to QEMU (fixed in
v6.6.0-rc1-3-g2249455654).
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Andrea Bolognani <abologna@redhat.com>
CVE-2020-14339
When building domain's private /dev in a namespace, libdevmapper
is consulted for getting full dependency tree of domain's disks.
The reason is that for a multipath devices all dependent devices
must be created in the namespace and allowed in CGroups.
However, this approach is very fragile as building of namespace
happens in the forked off child process, after mass close of FDs
and just before dropping privileges and execing QEMU. And it so
happens that when calling libdevmapper APIs, one of them opens
/dev/mapper/control and saves the FD into a global variable. The
FD is kept open until the lib is unlinked or dm_lib_release() is
called explicitly. We are doing neither.
However, the virDevMapperGetTargets() function is called also
from libvirtd (when setting up CGroups) and thus has to be thread
safe. Unfortunately, libdevmapper APIs are not thread safe (nor
async signal safe) and thus we can't use them. Reimplement what
libdevmapper would do using plain C (ioctl()-s, /proc/devices
parsing, /dev/mapper dirwalking, and so on).
Fixes: a30078cb83
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1858260
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Since we have VIR_AUTOSTRINGLIST we can use it to free string
lists used in the function automatically.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
There are two distinct WITH_DEVMAPPER sections in the file, for
different functions each. Rearrange the code to make some of
future commits smaller.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
In 9536379da4 and 8b0cb0e666 I've tried to call
virNetSocketCheckProtocolByLookup() only if we are suspecting the
host is IPv4 or IPv6 capable (because we've found an interface
with such address). However, the code was missing dereference of
the boolean variables and thus was comparing pointers against
NULL.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Historically, if we found an interface with an IPv6 address we
did not blindly trust that host is IPv6 capable (as in we can
successfully translate IPv4 addresses) but used getaddrinfo() to
confirm it. Turns out, we have use the same argument for IPv4.
For instance, in an namespace created by the following steps,
getaddrinfo("127.0.0.1", ...) fails (demonstrating by "Socket
TCP/IPv4 Accept" test case failing in virnetsockettest):
unshare -n
ip link set lo up
ip link add dummy0 type dummy
ip link set dummy0 up
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
There is not much sense trying to disprove host is IPv6 capable
if we know after first round (getifaddrs()) that is is not.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
The virNetSocketCheckProtocols() function is supposed to tell
caller whether IPv4 and/or IPv6 is supported on the system. In
the initial round, it uses getifaddrs() to see if an interface
has IPv4/IPv6 address assigned and then to double check IPv6 it
uses getaddrinfo() to lookup IPv6 loopback address. Separate out
this latter code because it is going to be reused.
Since the original code lived under an #ifdef and the new
function doesn't it is marked as unused - because on some systems
it may be so.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Just like in the previous commit, the stdin_path argument of
virSecurityManagerSetAllLabel() is renamed to incomingPath.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
The argument (if not NULL) points to the file the domain is
restoring from. On QEMU command line this used to be '-incoming
$path', but we've switched to passing FD ages ago and thus this
argument is used only in AppArmor (which loads the profile on
domain start). Anyway, the argument does not refer to stdin,
rename it to 'incomingPath' then.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
Currently, when restoring from a domain the path that the domain
restores from is labelled under qemuSecuritySetAllLabel() (and after
v6.3.0-rc1~108 even outside transactions). While this grants QEMU
the access, it has a flaw, because once the domain is restored, up
and running then qemuSecurityDomainRestorePathLabel() is called,
which is not real counterpart. In case of DAC driver the
SetAllLabel() does nothing with the restore path but
RestorePathLabel() does - it chown()-s the file back and since there
is no original label remembered, the file is chown()-ed to
root:root. While the apparent solution is to have DAC driver set the
label (and thus remember the original one) in SetAllLabel(), we can
do better.
Turns out, we are opening the file ourselves (because it may live on
a root squashed NFS) and then are just passing the FD to QEMU. But
this means, that we don't have to chown() the file at all, we need
to set SELinux labels and/or add the path to AppArmor profile.
And since we want to restore labels right after QEMU is done loading
the migration stream (we don't want to wait until
qemuSecurityRestoreAllLabel()), the best way to approach this is to
have separate APIs for labelling and restoring label on the restore
file.
I will investigate whether AppArmor can use the SavedStateLabel()
API instead of passing the restore path to SetAllLabel().
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1851016
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
These APIs are are basically
virSecuritySELinuxDomainSetPathLabelRO() and
virSecuritySELinuxDomainRestorePathLabel().
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
These APIs don't use namespaces because the
virSecurityManagerSetSavedStateLabel() runs
when the namespace doesn't exist yet and thus
the virSecurityManagerRestoreSavedStateLabel()
has to run without namespace too.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
These APIs were removed/renamed in v6.5.0-rc1~142 and v6.5.0-rc1~141
because they deemed unused. And if it wasn't for the RFE [1] things
would stay that way.
The RFE asks for us to not change DAC ownership on the file a domain is
restoring from. We have been doing that for ages (if not forever),
nevertheless it's annoying because if the restore file is on an NFS
remembering owner won't help - NFS doesn't support XATTRs yet. But more
importantly, there is no need for us to chown() the file because when
restoring the domain the file is opened and the FD is then passed to
QEMU. Therefore, we really need only to set SELinux and AppArmor.
This reverts bd22eec903.
This partially reverts 4ccbd207f2.
The difference to the original code is that secdrivers are now
not required to provide dummy implementation to avoid
virReportUnsupportedError(). The callback is run if it exists, if
it doesn't zero is returned without any error.
1: https://bugzilla.redhat.com/show_bug.cgi?id=1851016
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
When locking files for metadata change, we open() them for R/W
access. The write access is needed because we want to acquire
exclusive (write) lock (to mutually exclude with other daemons
trying to modify XATTRs on the same file). Anyway, the open()
might fail if the file lives on a RO filesystem. Well, if that's
the case, ignore the error and continue with the next file on the
list. We won't change any seclabel on the file anyway - there is
nothing to remember then.
Reported-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
In the light of recent commit of 9d83281382 fix the comment that
says directories can't be locked. Well, in general they can, but
not in our case.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
A few commits ago, in aeecbc87b7, I've implemented command line
generation for ACPI HMAT. For this, we need to know if at least
one guest NUMA node has vCPUs. This is tracked in
@masterInitiator variable, which is initialized to -1, then we
iterate through guest NUMA nodes and break the loop if we find a
node with a vCPU. After the loop, if masterInitiator is still
negative then no NUMA node has a vCPU and we error out. But this
exact check was missing comparison for negativeness.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
This capability tracks whether QEMU is capable of defining HMAT
ACPI table for the guest.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
These APIs will be used by QEMU driver when building the command
line.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
There are several restrictions, for instance @initiator and
@target have to refer to existing NUMA nodes (daa), @cache has to
refer to a defined cache level and so on.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
To cite ACPI specification:
Heterogeneous Memory Attribute Table describes the memory
attributes, such as memory side cache attributes and bandwidth
and latency details, related to the System Physical Address
(SPA) Memory Ranges. The software is expected to use this
information as hint for optimization.
According to our upstream discussion [1] this is exposed under
<numa/> as <cache/> under NUMA <cell/> and <latency> or
<bandwidth/> under numa/latencies.
1: https://www.redhat.com/archives/libvir-list/2020-January/msg00422.html
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
QEMU allows creating NUMA nodes that have memory only.
These are somehow important for HMAT.
With check done in qemuValidateDomainDef() for QEMU 2.7 or newer
(checked via QEMU_CAPS_NUMA), we can be sure that the vCPUs are
fully assigned to NUMA nodes in domain XML.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
There is only one caller of virDomainNumaSetNodeCpumask() which
checks for the return value but because the function will return
NULL iff the @cpumask was NULL in the first place. But in that
place @cpumask can't be NULL because it was just allocated by
virBitmapParse().
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
The machine can not be NULL at this point -
qemuDomainDefPostParse() makes sure it isn't.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
The function doesn't just build the argument for -numa. Since the
-numa can be repeated multiple times, it also puts -numa onto the
cmd line. Also, the rest of the functions has 'Command' infix.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Michal Privoznik