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>
btrfs defaults to performing copy-on-write for files. This is often
undesirable for VM images, so we need to be able to control whether this
behaviour is used.
The virFileSetCOW() will allow for this. We use a tristate, since out of
the box, we want the default behaviour attempt to disable cow, but only
on btrfs, silently do nothing on non-btrfs. If someone explicitly asks
to disable/enable cow, then we want to raise a hard error on non-btrfs.
Reviewed-by: Neal Gompa <ngompa13@gmail.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
gcc 10.1.0 on Debian sid has a bug where the bounds checking gets
confused beteen two branches:
In file included from /usr/include/string.h:495,
from ../../src/internal.h:28,
from ../../src/util/virsocket.h:21,
from ../../src/util/virsocketaddr.h:21,
from ../../src/util/virnetdevip.h:21,
from ../../src/util/virnetdevip.c:21:
In function 'memcpy',
inlined from 'virNetDevGetifaddrsAddress' at ../../src/util/virnetdevip.c:914:13,
inlined from 'virNetDevIPAddrGet' at ../../src/util/virnetdevip.c:962:16:
/usr/include/arm-linux-gnueabihf/bits/string_fortified.h:34:10: error: '__builtin_memcpy' offset [16, 27] from the object at 'addr' is out of the bounds of referenced subobject 'inet4' with type 'struct sockaddr_in' at offset 0 [-Werror=array-bounds]
34 | return __builtin___memcpy_chk (__dest, __src, __len, __bos0 (__dest));
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from ../../src/util/virnetdevip.h:21,
from ../../src/util/virnetdevip.c:21:
../../src/util/virnetdevip.c: In function 'virNetDevIPAddrGet':
../../src/util/virsocketaddr.h:29:28: note: subobject 'inet4' declared here
29 | struct sockaddr_in inet4;
| ^~~~~
cc1: all warnings being treated as errors
Note the source location is pointing to the "inet6" / AF_INET6 branch of
the "if", but is complaining about bounds of the "inet4" field. Changing
the code into a switch() is sufficient to avoid triggering the bug and
is arguably better code too.
Reviewed-by: Laine Stump <laine@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
g_new() is used in only 3 places. Switching them to g_new0() will do
no harm, reduces confusion, and helps me sleep better at night knowing
that all allocated memory is initialized to 0 :-) (Yes, I *know* that
in all three cases the associated memory is immediately assigned some
other value. Today.)
Signed-off-by: Laine Stump <laine@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Historically, we've used security_context_t for variables passed
to libselinux APIs. But almost 7 years ago, libselinux developers
admitted in their API that in fact, it's just a 'char *' type
[1]. Ever since then the APIs accept 'char *' instead, but they
kept the old alias just for API stability. Well, not anymore [2].
1: 9eb9c93275
2: 7a124ca275
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Andrea Bolognani <abologna@redhat.com>
Commit <f650e86703847af544762d02f79c70131ff7fbab> added check for
openpty function from util library using AC_CHECK_LIB(). However, that
macro doesn't define OPENPTY_LIBS, it only defines WITH_LIBUTIL and
prepends -lutil into LIBS for the whole project.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
It was introduced by commit <c606671aaad10a9bc87f226bc473a091e00a9629>
as a gnulib ldexp module and later removed by commit
<09fe607b4de8eb883c966e90aaf5563299a22738>.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Fixes inconsistency with macro names for external programs.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
This was introduced together with clock-time gnulib module by commit
<d74e5a4dfc434d3a1d01856d013a7f50d910fa95> and removed from libvirt
by commit <86d223a762990c9d529065a2d3b30b6a00ea63dd>.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
virFileIsAccessible does not return true on accessible
directories. Check whether it set EISDIR and only
then assume the directory is inaccessible.
Return 0 (not found) instead of 1 (found),
since the bridge driver taints the network based on
this return value, not whether the hook actually ran.
Remove the bogus check from virHookCall, since it already
checks the virHooksFound bitmap that was filled before
by virHookCheck.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Fixes: 7fa7f7eeb6
Closes: https://gitlab.com/libvirt/libvirt/-/issues/47
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
When preparing for the removal of GNULIB commit 18dca21a32 removed the
unneeded O_DIRECTORY, but unfortunately started opening the directory for
writing which fails every time for a directory. There is also no need for that
as flock() works on O_RDONLY file descriptor as well, even for LOCK_EX.
https://bugzilla.redhat.com/1852741
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Andrea Bolognani <abologna@redhat.com>
There are several calls to virBufferFreeAndReset() when functions
encounter an error, but the caller never uses the virBuffer once an
error has been encountered (all callers detect error by looking at the
function return value, not the contents of the virBuffer being
operated on), and now that all virBuffers are auto-freed there is no
reason for the lower level functions like these to spend time freeing
a buffer that is guaranteed to be freed momentarily anyway.
Signed-off-by: Laine Stump <laine@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
The idea is to have a function that calls virHostCPUGetOnlineBitmap()
but, instead of returning NULL if the host does not have CPU
offlining capabilities, fall back to a bitmap containing all
present CPUs.
Next patch will use this helper in two other places.
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
This function reads the string in sysfspath/cpu/present and
parses it manually to retrieve the number of present CPUs.
virHostCPUGetPresentBitmap() reads and parses the same file,
using a more robust parser via virBitmapParseUnlimited(),
but returns a bitmap. Let's drop all the manual parsing done
here and simply return the size of the resulting bitmap
from virHostCPUGetPresentBitmap().
Given that no more parsing is being done manually in the function,
rename it to virHostCPUCountLinux().
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
There is nothing domain specific about the function, thus it
should not have virDomain prefix. Also, the fact that it is a
static function makes it impossible to use from other files.
Move the function to virxml.c and drop the 'Domain' infix.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
The strings allocated in virGetHostnameImpl() are all allocated via
g_strdup(), which will exit on OOM anyway, so the call to
virReportOOMError() is redundant, and removing it allows slight
modification to the code, in particular the cleanup label can be
eliminated.
Signed-off-by: Laine Stump <laine@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
AUTOPTR_CLEANUP_FUNC is set to xmlBufferFree() in util/virxml.h (This
is actually new - added accidentally (but fortunately harmlessly!) in
commit 257aba2daf. I had added it along with the hunks in this patch,
then decided to remove it and submit separately, but missed taking out
the hunk in virxml.h)
Signed-off-by: Laine Stump <laine@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Since feb83c1e71 libvirtd will abort on
startup if run as non-root
2020-07-01 16:30:30.738+0000: 1647444: error : virDirOpenInternal:2869 : cannot open directory '/etc/libvirt/hooks/daemon.d': Permission denied
The root cause flaw is that non-root libvirtd is using /etc/libvirt for
its hooks. Traditionally that has been harmless though since we checked
whether we could access the hook file and degraded gracefully. We need
the same access check for iterating over the hook directory.
Long term we should make it possible to have an unprivileged hook dir
under $HOME.
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
The ZPCI device validation is specific to qemu. So, let us move the
ZPCI uid validation out of domain xml parsing into qemu domain device
validation.
Signed-off-by: Shalini Chellathurai Saroja <shalini@linux.ibm.com>
Reviewed-by: Bjoern Walk <bwalk@linux.ibm.com>
Reviewed-by: Boris Fiuczynski <fiuczy@linux.ibm.com>
Reviewed-by: Andrea Bolognani <abologna@redhat.com>
Let us fix the issues with zPCI address validation and auto-generation
on s390.
Currently, there are two issues with handling the ZPCI address
extension. Firstly, when the uid is to be auto-generated with a
specified fid, .i.e.:
...
<address type='pci'>
<zpci fid='0x0000001f'/>
</address>
...
we expect uid='0x0001' (or the next available uid for the domain).
However, we get a parsing error:
$ virsh define zpci.xml
error: XML error: Invalid PCI address uid='0x0000', must be > 0x0000
and <= 0xffff
Secondly, when the uid is specified explicitly with the invalid
numerical value '0x0000', we actually expect the parsing error above.
However, the domain is being defined and the uid value is silently
changed to a valid value.
The first issue is a bug and the second one is undesired behaviour, and
both issues are related to how we (in-band) signal invalid values for
uid and fid. So let's fix the XML parsing to do validation based on what
is actually specified in the XML.
The first issue is also related to the current code behaviour, which
is, if either uid or fid is specified by the user, it is incorrectly
assumed that both uid and fid are specified. This bug is fixed by
identifying when the user specified ZPCI address is incomplete and
auto-generating the missing ZPCI address.
Signed-off-by: Bjoern Walk <bwalk@linux.ibm.com>
Signed-off-by: Boris Fiuczynski <fiuczy@linux.ibm.com>
Signed-off-by: Shalini Chellathurai Saroja <shalini@linux.ibm.com>
Reviewed-by: Andrea Bolognani <abologna@redhat.com>
Refer to the notion of mount propagation instead which describes
the actual behaviour more clearly.
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
The two sides of a PTY can be referred to as primary and secondary
TTYs.
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
This new naming matches the terminology used in the error
messages that the callers report.
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
The term "access control list" better describes the concept involved.
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
The XML format used for QEMU capabilities is not required to be
stable across releases, as we invalidate the cache whenever the
libvirt binary changes.
We none the less always try to parse te entire XML file before
we do any validity checks. Thus if we change the format of any
part of the data, or change permitted values for enums, then
libvirtd logs will be spammed with errors.
These are not in fact errors, but an expected scenario.
This change makes the loading code validate the cache timestamp
against the libvirtd timestamp immediately. If they don't match
then we stop loading the rest of the XML file.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
It is easier for management software (and subsequently
distributions) to install hook script under
/etc/libvirt/hooks/$driver.d/ and have libvirt execute them in
alphabetical order. To maintain backwards compatibility,
/etc/libvirt/hooks/$driver hook script is executed the first
followed by scripts from the $driver.d directory.
The stdio is chained between the scripts. The output of the first
script is input of the second and so on.
Signed-off-by: Dmitry Nesterenko <dmitry.nesterenko@virtuozzo.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
This refactor is needed to support support hooks placed in
several files.
Signed-off-by: Dmitry Nesterenko <dmitry.nesterenko@virtuozzo.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Using virKModConfig would not simplify any existing code.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
All callers except for the test suite pass the same value
for the second arg, so it can be removed, simplifying the
code.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Mediated devices support arbitrary vendor-specific attributes that can
be attached to a mediated device. These attributes are ordered, and are
written to sysfs in order after a device is created. This patch adds
support for these attributes to the mdev data types and XML schema.
Signed-off-by: Jonathon Jongsma <jjongsma@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Introduced by commit 72ab0b6dc8 which
added some code depending on libvirt's log format string into
qemuProcessReadLogOutput. This function was deleted by commit
932534e85f later.
Drop the comment.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Closes: https://gitlab.com/libvirt/libvirt/-/issues/35
In v6.4.0-72-g3dda889a44 I've introduced parsing and formatting
of new sysinfo type 'fwcfg'. However, I've forgot to introduce
code that would free parsed data.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Since 9ea90206, @drvpath could be overwritten if we jumped to recheck
Found by Coverity.
Signed-off-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
Since 5084091a, @authcred is filled by a g_key_file_get_string which is
now an allocated string as opposed to some hash table lookup value, so
we need to treat it as so.
Found by Coverity
Signed-off-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
Since 5084091a, @tmp is filled by a g_key_file_get_string which is
now an allocated string as opposed to some hash table lookup value,
so we need to treat it as so.
Found by Coverity
Signed-off-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
Introduce two utility functions to parse a kernel command
line string according to the kernel code parsing rules in
order to enable the caller to perform operations such as
verifying whether certain argument=value combinations are
present or retrieving an argument's value.
Signed-off-by: Paulo de Rezende Pinatti <ppinatti@linux.ibm.com>
Signed-off-by: Boris Fiuczynski <fiuczy@linux.ibm.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
This was mostly boilerplate conversion, but in one case I needed to
define several differently named char* to take the place of a single
char *tmp that was re-used multiple times, and in another place there
was a single char* that was used at the toplevel of the function, and
then later used repeatedly inside a for loop, so I defined a new
separate char* inside the loop.
Signed-off-by: Laine Stump <laine@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
IPv6 does support masquerade since Linux 3.9.0 / ip6tables 1.4.18,
which is Fedora 18 / RHEL-7 vintage, which covers all our supported
Linux versions.
Reviewed-by: Laine Stump <laine@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
In v6.4.0-rc1~143 I've introduced a check that is supposed to
return from the function early, if given path is not a dm target.
While the idea is still valid, the implementation had a flaw.
It calls stat() over given path and the uses major(sb.st_dev) to
learn the major of the device. This is then passed to
dm_is_dm_major() which returns true or false depending whether
the device is under devmapper's control or not.
The problem with this approach is in how the major of the device
is obtained - paths managed by devmapper are special files and
thus we want to be using st_rdev instead of st_dev to obtain the
major number. Well, that's what virIsDevMapperDevice() does
already so might as well us that.
Fixes: 01626c668e
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1839992
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Jiri Denemark <jdenemar@redhat.com>
