819c141...
by
Jiri Denemark <email address hidden>
qemu: Let empty default VNC password work as documented
CVE-2016-5008
Setting an empty graphics password is documented as a way to disable
VNC/SPICE access, but QEMU does not always behaves like that. VNC would
happily accept the empty password. Let's enforce the behavior by setting
password expiration to "now".
CVE-2015-5313: storage: don't allow '/' in filesystem volume names
The libvirt file system storage driver determines what file to
act on by concatenating the pool location with the volume name.
If a user is able to pick names like "../../../etc/passwd", then
they can escape the bounds of the pool. For that matter,
virStoragePoolListVolumes() doesn't descend into subdirectories,
so a user really shouldn't use a name with a slash.
Normally, only privileged users can coerce libvirt into creating
or opening existing files using the virStorageVol APIs; and such
users already have full privilege to create any domain XML (so it
is not an escalation of privilege). But in the case of
fine-grained ACLs, it is feasible that a user can be granted
storage_vol:create but not domain:write, and it violates
assumptions if such a user can abuse libvirt to access files
outside of the storage pool.
Therefore, prevent all use of volume names that contain "/",
whether or not such a name is actually attempting to escape the
pool.
Well, in 8ad126e6 we tried to fix a memory corruption problem.
However, the fix was not as good as it could be. I mean, the
commit has one line more than it should. I've noticed this output
just recently:
# ./run valgrind --leak-check=full --show-reachable=yes ./tools/virsh domblklist gentoo
==17019== Memcheck, a memory error detector
==17019== Copyright (C) 2002-2013, and GNU GPL'd, by Julian Seward et al.
==17019== Using Valgrind-3.10.1 and LibVEX; rerun with -h for copyright info
==17019== Command: /home/zippy/work/libvirt/libvirt.git/tools/.libs/virsh domblklist gentoo
==17019==
Target Source
------------------------------------------------
fda /var/lib/libvirt/images/fd.img
vda /var/lib/libvirt/images/gentoo.qcow2
hdc /home/zippy/tmp/install-amd64-minimal-20150402.iso
==17019== Thread 2:
==17019== Invalid read of size 4
==17019== at 0x4EFF5B4: virObjectUnref (virobject.c:258)
==17019== by 0x5038CFF: remoteClientCloseFunc (remote_driver.c:552)
==17019== by 0x5069D57: virNetClientCloseLocked (virnetclient.c:685)
==17019== by 0x506C848: virNetClientIncomingEvent (virnetclient.c:1852)
==17019== by 0x5082136: virNetSocketEventHandle (virnetsocket.c:1913)
==17019== by 0x4ECD64E: virEventPollDispatchHandles (vireventpoll.c:509)
==17019== by 0x4ECDE02: virEventPollRunOnce (vireventpoll.c:658)
==17019== by 0x4ECBF00: virEventRunDefaultImpl (virevent.c:308)
==17019== by 0x130386: vshEventLoop (vsh.c:1864)
==17019== by 0x4F1EB07: virThreadHelper (virthread.c:206)
==17019== by 0xA8462D3: start_thread (in /lib64/libpthread-2.20.so)
==17019== by 0xAB441FC: clone (in /lib64/libc-2.20.so)
==17019== Address 0x139023f4 is 4 bytes inside a block of size 240 free'd
==17019== at 0x4C2B1F0: free (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
==17019== by 0x4EA8949: virFree (viralloc.c:582)
==17019== by 0x4EFF6D0: virObjectUnref (virobject.c:273)
==17019== by 0x4FE74D6: virConnectClose (libvirt.c:1390)
==17019== by 0x13342A: virshDeinit (virsh.c:406)
==17019== by 0x134A37: main (virsh.c:950)
The problem is, when registering remoteClientCloseFunc(), it's
conn->closeCallback which is ref'd. But in the function itself
it's conn->closeCallback->conn what is unref'd. This is causing
imbalance in reference counting. Moreover, there's no need for
the remote driver to increase/decrease conn refcount since it's
not used anywhere. It's just merely passed to client registered
callback. And for that purpose it's correctly ref'd in
virConnectRegisterCloseCallback() and then unref'd in
virConnectUnregisterCloseCallback().
Signed-off-by: Michal Privoznik <email address hidden>
(cherry picked from commit e68930077034f786e219bdb015f8880dbc5a246f)
Signed-off-by: Michal Privoznik <email address hidden>
Revert "LXC: show used memory as 0 when domain is not active"
This reverts commit 1ce7c1d20cfd5afb26d2dbc88201085d52415d0e,
which introduced a significant semantic change to the
virDomainGetInfo() API. Additionally, the change was only
made to 2 of the 15 virt drivers.
Conflicts:
src/qemu/qemu_driver.c
Signed-off-by: Jim Fehlig <email address hidden>
(cherry picked from commit 60acb38abbee1636a9cddf8d296f700d115c8f77)
lxc: set nosuid+nodev+noexec flags on /proc/sys mount
Future kernels will mandate the use of nosuid+nodev+noexec
flags when mounting the /proc/sys filesystem. Unconditionally
add them now since they don't harm things regardless and could
mitigate future security attacks.
(cherry picked from commit 24710414d403f1040794299f5304fee160d0fc23)
The cpu xml copy is incorrect: the memAccess field is not copied.
The lack of copy of this memAccess field can cause unexpected behaviour for live
migration when vhost user is used.
For example if guest has the following configuration:
....
<cpu>
<model>Westmere</model>
<topology sockets="1" cores="4" threads="1"/>
<numa>
<cell id='0' cpus='0-3' memory='2097152' memAccess='shared'/>
</numa>
</cpu>
....
The used configuration on the remote host in case of live migration is:
....
<cpu mode='custom' match='exact'>
<model fallback='allow'>Westmere</model>
<topology sockets='1' cores='4' threads='1'/>
<numa>
<cell id='0' cpus='0-3' memory='2097152' unit='KiB'/>
</numa>
</cpu>
....
On the remote host the lack of memAccess info can cause unexpected error on the
qemu backend vhost user driver.
Fixes: def6b3598 ("docs, conf, schema: add support for shared memory mapping")
This issue is present only for libvirt1.2.9 to libvirt1.2.12
With patch 181742d43 ("conf: Move all NUMA configuration to virDomainNuma")
present since libvirt1.2.13 the problem does not exist anymore as NUMA
information are no more in the CPU configuration.
daemon: avoid memleak when ListAll returns nothing
Commit 4f25146 (v1.2.8) managed to silence Coverity, but at the
cost of a memory leak detected by valgrind:
==24129== 40 bytes in 5 blocks are definitely lost in loss record 355 of 637
==24129== at 0x4A08B1C: realloc (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
==24129== by 0x5084B8E: virReallocN (viralloc.c:245)
==24129== by 0x514D5AA: virDomainObjListExport (domain_conf.c:22200)
==24129== by 0x201227DB: qemuConnectListAllDomains (qemu_driver.c:18042)
==24129== by 0x51CC1B6: virConnectListAllDomains (libvirt-domain.c:6797)
==24129== by 0x14173D: remoteDispatchConnectListAllDomains (remote.c:1580)
==24129== by 0x121BE1: remoteDispatchConnectListAllDomainsHelper (remote_dispatch.h:1072)
In short, every time a client calls a ListAll variant and asks
for the resulting list, but there are 0 elements to return, we
end up leaking the 1-entry array that holds the NULL terminator.
What's worse, a read-only client can access these functions in a
tight loop to cause libvirtd to eventually run out of memory; and
this can be considered a denial of service attack against more
privileged clients. Thankfully, the leak is so small (8 bytes per
call) that you would already have some other denial of service with
any guest calling the API that frequently, so an out-of-memory
crash is unlikely enough that this did not warrant a CVE.
