Systemd uses a named cgroup mount for tracking processes. Add
it as another type of controller, albeit one which we have to
special case in a number of places. In particular we must
never create/delete directories there, nor add tasks. Essentially
the systemd mount is to be considered read-only for libvirt.
With this change both the virCgroupDetectPlacement and
virCgroupCopyPlacement methods must be invoked. The copy
placement method will copy setup for resource controllers
only. The detect placement method will probe for any
named controllers, or resource controllers not already
setup.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
There are some interesting escaping rules to consider when dealing
with systemd slice/scope names. Thus it is helpful to have APIs
for formatting names
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
This function is needed for virt-login-shell. Also modify virGirUserDirectory
to use the new function, to simplify the code.
Signed-off-by: Eric Blake <eblake@redhat.com>
The way we were casting small (<32bit) integers was broken
on big endian hosts, causing stack smashing. This was detected
in the test suite either by test failures due to incorrect
results, or by libc/gcc abort'ing with its stack canary
triggered.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Depending on the set of mingw packages installed, it is possible
that other .c files hit the mingw header pollution from the
virdbus.h file.
In file included from ../../src/rpc/virnetserver.c:39:0:
../../src/util/virdbus.h:41:35: error: expected ';', ',' or ')' before 'struct'
const char *interface,
^
* src/util/virdbus.h (virDBusCallMethod): Match .c file change.
Signed-off-by: Eric Blake <eblake@redhat.com>
On platforms without decent group support, the build failed:
Cannot export virGetGroupList: symbol not defined
./.libs/libvirt_security_manager.a(libvirt_security_manager_la-security_dac.o): In function `virSecurityDACPreFork':
/home/eblake/libvirt-tmp/build/src/../../src/security/security_dac.c:248: undefined reference to `virGetGroupList'
collect2: error: ld returned 1 exit status
* src/util/virutil.c (virGetGroupList): Provide dummy implementation.
Signed-off-by: Eric Blake <eblake@redhat.com>
Our recent conversion to make VIR_ALLOC report oom wasn't
tested on mingw:
In file included from ../../src/util/virthread.c:29:0:
../../src/util/virthreadwin32.c: In function 'virCondWait':
../../src/util/virthreadwin32.c:166:81: error: 'VIR_FROM_THIS' undeclared (first use in this function)
if (VIR_REALLOC_N(c->waiters, c->nwaiters + 1) < 0) {
^
* src/util/virthreadwin32.c (VIR_FROM_THIS): Define.
Signed-off-by: Eric Blake <eblake@redhat.com>
The previous patch was incomplete.
CC libvirt_util_la-vircgroup.lo
../../src/util/vircgroup.c:70:12: error: 'virCgroupPartitionEscape' declared 'static' but never defined [-Werror=unused-function]
static int virCgroupPartitionEscape(char **path);
^
* src/util/vircgroup.c (virCgroupPartitionEscape): Move forward
declaration inside conditional.
Signed-off-by: Eric Blake <eblake@redhat.com>
The virCgroupValidateMachineGroup method calls some functions
which are only conditionally compiled, thus it too must be
made conditional. This fixes the build on non-Linux hosts.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
If the app has provided a whitelist of controllers to be used,
we skip detecting its mount point. We still, however, fill in
the placement info which later confuses the machine name
validation code. Skip detecting placement if the controller
mount point is not set
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
When a VM has an 'emulator' child cgroup present, we must
strip off that suffix when detecting the cgroup for a
machine
Rename the virCgroupIsValidMachineGroup method to
virCgroupValidateMachineGroup to make a bit clearer
that this isn't simply a boolean check, it will make
changes to the object.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The virCgroupIsValidMachine does not need to be called from
outside the cgroups file now, so make it static.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Instead of requiring drivers to use a combination of calls
to virCgroupNewDetect and virCgroupIsValidMachine, combine
the two into virCgroupNewDetectMachine
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Add protection such that the virCgroupRemove and
virCgroupKill* do not do anything to the root cgroup.
Killing all PIDs in the root cgroup does not end well.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Instead of requiring one API call to create a cgroup and
another to add a task to it, introduce a new API
virCgroupNewMachine which does both jobs at once. This
will facilitate the later code to talk to systemd to
achieve this job which is also atomic.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
virCgroupAvailable() implementation calls getmntent_r
without checking if HAVE_GETMNTENT_R is defined, so it fails
to build on platforms without getmntent_r support.
Make virCgroupAvailable() just return false without
HAVE_GETMNTENT_R.
Parsing 'user:group' is useful even outside the DAC security driver,
so expose the most abstract function which has no DAC security driver
bits in itself.
Thanks to a lack of coordination between kernel and glibc folks,
it has been impossible to mix code using <linux/in.h> and
<net/in.h> for some time now (see for example commit c308a9a).
On at least RHEL 6, <linux/if_bridge.h> tries to use the kernel
side, and fails due to our desire to use the glibc side elsewhere:
In file included from /usr/include/linux/if_bridge.h:17,
from util/virnetdevbridge.c:42:
/usr/include/linux/in6.h:31: error: redefinition of ‘struct in6_addr’
/usr/include/linux/in6.h:48: error: redefinition of ‘struct sockaddr_in6’
/usr/include/linux/in6.h:56: error: redefinition of ‘struct ipv6_mreq’
Thankfully, the kernel layout of these structs is ABI-compatible,
they only differ in the type system presented to the C compiler.
While there are other versions of kernel headers that avoid the
problem, it is easier to just work around the issue than to expect
all developers to upgrade to working kernel headers.
* src/util/virnetdevbridge.c (includes): Coerce the kernel version
of in.h to not collide with the normal version.
Signed-off-by: Eric Blake <eblake@redhat.com>
dbus 1.2.24 (on RHEL 6) lacks DBUS_TYPE_UNIX_FD; but as we aren't
trying to pass one of those anyways, we can just drop support for
it in our wrapper. Solves this build error introduced in commit
834c9c94:
CC libvirt_util_la-virdbus.lo
util/virdbus.c:242: error: 'DBUS_TYPE_UNIX_FD' undeclared here (not in a function)
* src/util/virdbus.c (virDBusBasicTypes): Drop support for unix fds.
Signed-off-by: Eric Blake <eblake@redhat.com>
The virCgroupNewDomainDriver and virCgroupNewDriver methods
are obsolete now that we can auto-detect existing cgroup
placement. Delete them to reduce code bloat.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Add virCgroupIsValidMachine API to check whether an auto
detected cgroup is valid for a machine. This lets us
check if a VM has just been placed into some generic
shared cgroup, or worse, the root cgroup
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Add a virCgroupNewDetect API which is used to initialize a
cgroup object with the placement of an arbitrary process.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
If systemd machine does not exist, return -2 instead of -1,
so that applications don't need to repeat the tedious error
checking code
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Current code for handling dbus errors only works for errors
received from the remote application itself. We must also
handle errors emitted by the bus itself, for example, when
it fails to spawn the target service.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Commit 834c9c94 introduced virDBusMessageEncode and
virDBusMessageDecode functions, however corresponding stubs
were not added to !WITH_DBUS section, therefore 'make check'
started to fail when compiled w/out dbus support like that:
Expected symbol virDBusMessageDecode is not in ELF library
Convert the remaining methods in vircgroup.c to report errors
instead of returning errno values.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Add virErrorSetErrnoFromLastError and virLastErrorIsSystemErrno
to simplify code which wants to handle system errors in a more
graceful fashion.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
To register virtual machines and containers with systemd-machined,
and thus have cgroups auto-created, we need to talk over DBus.
This is somewhat tedious code, so introduce a dedicated function
to isolate the DBus call in one place.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Doing DBus method calls using libdbus.so is tedious in the
extreme. systemd developers came up with a nice high level
API for DBus method calls (sd_bus_call_method). While
systemd doesn't use libdbus.so, their API design can easily
be ported to libdbus.so.
This patch thus introduces methods virDBusCallMethod &
virDBusMessageRead, which are based on the code used for
sd_bus_call_method and sd_bus_message_read. This code in
systemd is under the LGPLv2+, so we're license compatible.
This code is probably pretty unintelligible unless you are
familiar with the DBus type system. So I added some API
docs trying to explain how to use them, as well as test
cases to validate that I didn't screw up the adaptation
from the original systemd code.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
When virAsprintf was changed from a function to a macro
reporting OOM error in dc6f2da, it was documented as returning
0 on success. This is incorrect, it returns the number of bytes
written as asprintf does.
Some of the functions were converted to use virAsprintf's return
value directly, changing the return value on success from 0 to >= 0.
For most of these, this is not a problem, but the change in
virPCIDriverDir breaks PCI passthrough.
The return value check in virhashtest pre-dates virAsprintf OOM
conversion.
vmwareMakePath seems to be unused.
Merge the virCommandPreserveFD / virCommandTransferFD methods
into a single virCommandPasFD method, and use a new
VIR_COMMAND_PASS_FD_CLOSE_PARENT to indicate their difference
in behaviour
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reuse the buffer for getline and track buffer allocation
separately from the string length to prevent unlikely
out-of-bounds memory access.
This fixes the following leak that happened when zero bytes were read:
==404== 120 bytes in 1 blocks are definitely lost in loss record 1,344 of 1,671
==404== at 0x4C2C71B: malloc (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
==404== by 0x906F862: getdelim (iogetdelim.c:68)
==404== by 0x52A48FB: virCgroupPartitionNeedsEscaping (vircgroup.c:1136)
==404== by 0x52A0FB4: virCgroupPartitionEscape (vircgroup.c:1171)
==404== by 0x52A0EA4: virCgroupNewDomainPartition (vircgroup.c:1450)
I recently patches the callers to virPCIDeviceReset() to not call it
if the current driver for a device was vfio-pci (since that driver
will always reset the device itself when appropriate. At the time, Dan
Berrange suggested that I could instead modify virPCIDeviceReset
to check the currently bound driver for the device, and decide
for itself whether or not to go ahead with the reset.
This patch removes the previously added checks, and replaces them with
a check down in virPCIDeviceReset(), as suggested.
The functional difference here is that previously we were deciding
based on either the hostdev configuration or the value of
stubDriverName in the virPCIDevice object, but now we are actually
comparing to the "driver" link in the device's sysfs entry
directly. In practice, both should be the same.
virPCIDeviceGetDriverPathAndName is a static function that will need
to be called by another function that occurs above it in the
file. This patch reorders the static functions so that a forward
declaration isn't needed.
Previously a connection object was required to retrieve the auth
credentials. This patch adds the option to call the retrieval functions
only using the connection URI or path to the configuration file. This
will allow to use this toolkit to request passwords for ssh
authentication in the libssh2 connection driver.
Changes:
*virAuthGetConfigFilePathURI(): use URI to retrieve the config file path
*virAuthGetCredential(): Remove the need to propagate conn object
virAuthGetPasswordPath():
*virAuthGetUsernamePath(): New functions, that use config file path
instead of conn object
https://bugzilla.redhat.com/show_bug.cgi?id=964358
POSIX states that multi-threaded apps should not use functions
that are not async-signal-safe between fork and exec, yet we
were using getpwuid_r and initgroups. Although rare, it is
possible to hit deadlock in the child, when it tries to grab
a mutex that was already held by another thread in the parent.
I actually hit this deadlock when testing multiple domains
being started in parallel with a command hook, with the following
backtrace in the child:
Thread 1 (Thread 0x7fd56bbf2700 (LWP 3212)):
#0 __lll_lock_wait ()
at ../nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:136
#1 0x00007fd5761e7388 in _L_lock_854 () from /lib64/libpthread.so.0
#2 0x00007fd5761e7257 in __pthread_mutex_lock (mutex=0x7fd56be00360)
at pthread_mutex_lock.c:61
#3 0x00007fd56bbf9fc5 in _nss_files_getpwuid_r (uid=0, result=0x7fd56bbf0c70,
buffer=0x7fd55c2a65f0 "", buflen=1024, errnop=0x7fd56bbf25b8)
at nss_files/files-pwd.c:40
#4 0x00007fd575aeff1d in __getpwuid_r (uid=0, resbuf=0x7fd56bbf0c70,
buffer=0x7fd55c2a65f0 "", buflen=1024, result=0x7fd56bbf0cb0)
at ../nss/getXXbyYY_r.c:253
#5 0x00007fd578aebafc in virSetUIDGID (uid=0, gid=0) at util/virutil.c:1031
#6 0x00007fd578aebf43 in virSetUIDGIDWithCaps (uid=0, gid=0, capBits=0,
clearExistingCaps=true) at util/virutil.c:1388
#7 0x00007fd578a9a20b in virExec (cmd=0x7fd55c231f10) at util/vircommand.c:654
#8 0x00007fd578a9dfa2 in virCommandRunAsync (cmd=0x7fd55c231f10, pid=0x0)
at util/vircommand.c:2247
#9 0x00007fd578a9d74e in virCommandRun (cmd=0x7fd55c231f10, exitstatus=0x0)
at util/vircommand.c:2100
#10 0x00007fd56326fde5 in qemuProcessStart (conn=0x7fd53c000df0,
driver=0x7fd55c0dc4f0, vm=0x7fd54800b100, migrateFrom=0x0, stdin_fd=-1,
stdin_path=0x0, snapshot=0x0, vmop=VIR_NETDEV_VPORT_PROFILE_OP_CREATE,
flags=1) at qemu/qemu_process.c:3694
...
The solution is to split the work of getpwuid_r/initgroups into the
unsafe portions (getgrouplist, called pre-fork) and safe portions
(setgroups, called post-fork).
* src/util/virutil.h (virSetUIDGID, virSetUIDGIDWithCaps): Adjust
signature.
* src/util/virutil.c (virSetUIDGID): Add parameters.
(virSetUIDGIDWithCaps): Adjust clients.
* src/util/vircommand.c (virExec): Likewise.
* src/util/virfile.c (virFileAccessibleAs, virFileOpenForked)
(virDirCreate): Likewise.
* src/security/security_dac.c (virSecurityDACSetProcessLabel):
Likewise.
* src/lxc/lxc_container.c (lxcContainerSetID): Likewise.
* configure.ac (AC_CHECK_FUNCS_ONCE): Check for setgroups, not
initgroups.
Signed-off-by: Eric Blake <eblake@redhat.com>
Since neither getpwuid_r() nor initgroups() are safe to call in
between fork and exec (they obtain a mutex, but if some other
thread in the parent also held the mutex at the time of the fork,
the child will deadlock), we have to split out the functionality
that is unsafe. At least glibc's initgroups() uses getgrouplist
under the hood, so the ideal split is to expose getgrouplist for
use before a fork. Gnulib already gives us a nice wrapper via
mgetgroups; we wrap it once more to look up by uid instead of name.
* bootstrap.conf (gnulib_modules): Add mgetgroups.
* src/util/virutil.h (virGetGroupList): New declaration.
* src/util/virutil.c (virGetGroupList): New function.
* src/libvirt_private.syms (virutil.h): Export it.
Signed-off-by: Eric Blake <eblake@redhat.com>
A future patch needs to look up pw_gid; but it is wasteful
to crawl through getpwuid_r twice for two separate pieces
of information, and annoying to copy that much boilerplate
code for doing the crawl. The current internal-only
virGetUserEnt is also a rather awkward interface; it's easier
to just design it to let callers request multiple pieces of
data as needed from one traversal.
And while at it, I noticed that virGetXDGDirectory could deref
NULL if the getpwuid_r lookup fails.
* src/util/virutil.c (virGetUserEnt): Alter signature.
(virGetUserDirectory, virGetXDGDirectory, virGetUserName): Adjust
callers.
Signed-off-by: Eric Blake <eblake@redhat.com>
Recent changes uncovered a NEGATIVE_RETURNS in the return from sysconf()
when processing a for loop in virtTestCaptureProgramExecChild() in
testutils.c
Code review uncovered 3 other code paths with the same condition that
weren't found by Covirity, so fixed those as well.
I had made the change locally, so make check and make syntax-check
were successful, but forgot to add/commit. Unfortunately, git allows a
push when the local directory is dirty, so it didn't catch my mistake.
Eliminate memmove() by using VIR_*_ELEMENT API instead.
In both pci and usb cases, the count that held the size of the list
was unsigned int so it had to be changed to size_t.
Convert the type of loop iterators named 'i', 'j', k',
'ii', 'jj', 'kk', to be 'size_t' instead of 'int' or
'unsigned int', also santizing 'ii', 'jj', 'kk' to use
the normal 'i', 'j', 'k' naming
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
