Commit Graph

274 Commits

Author SHA1 Message Date
Daniel P. Berrange
93a18bbafa Treat failure to relabel stdin_path as non-fatal on NFS
NFS does not support file labelling, so ignore this error
for stdin_path when on NFS.

* src/security/security_selinux.c: Ignore failures on labelling
  stdin_path on NFS
* src/util/storage_file.c, src/util/storage_file.h: Refine
  virStorageFileIsSharedFS() to allow it to check for a
  specific FS type.
2010-11-02 14:38:19 +00:00
Jiri Denemark
53618145ee Fix several warnings about a non-literal format string
They only popped up during --disable-nls build. Without this configure
option, gcc wasn't able to detect them.
2010-11-02 09:47:22 +01:00
Osier Yang
af3ba2cd50 util: Add helper function to build timestamp string
* src/util/util.h
* src/util/util.c
* src/libvirt_private.syms
2010-11-01 17:05:11 -06:00
Lai Jiangshan
41b2cee2a8 qemu_driver: add virCgroupMounted
When we mount any cgroup without "-o devices", we will fail to start vms:

error: Failed to start domain vm1
error: Unable to deny all devices for vm1: No such file or directory

When we mount any cgroup without "-o cpu", we will fail to get schedinfo:
Scheduler      : posix
error: unable to get cpu shares tunable: No such file or directory

We should only use the cgroup controllers which are mounted on host.
So I add virCgroupMounted() for qemuCgroupControllerActive()

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
2010-10-29 09:46:25 -06:00
KAMEZAWA Hiroyuki
5546034210 audit: printf warning fix
fix warning
  CC     libvirt_util_la-virtaudit.lo
cc1: warnings being treated as errors
util/virtaudit.c: In function 'virAuditEncode':
util/virtaudit.c:146: error: implicit declaration of function 'virAsprintf' [-Wimplicit-function-declaration]
util/virtaudit.c:146: error: nested extern declaration of 'virAsprintf' [-Wnested-externs]
2010-10-28 11:23:42 -06:00
Matthias Bolte
8578df6a49 mingw: Add body for virFork and remove double virDriverLoadModule export
Commit 9bd3cce0d2 added virFork and
virDriverLoadModule to libvirt_private.syms, but virFork didn't have
a body on Win32 and virDriverLoadModule was already correctly
exported conditional via libvirt_driver_modules.syms.
2010-10-27 21:27:19 +02:00
Daniel P. Berrange
55a9938333 Add printf format attribute annotation to virAuditSend method
* src/util/virtaudit.h: Add printf format attribute annotation
2010-10-27 17:03:21 +01:00
Daniel P. Berrange
6a75a3fa3d Add audit helper for escaping log message strings
Add a helper API for ecscaping the value in audit log
messages

* src/util/virtaudit.h, src/util/virtaudit.c,
  src/libvirt_private.syms: Add virAuditEncode
2010-10-27 17:03:21 +01:00
Daniel P. Berrange
eff1735e42 Fix formatting of network address in iptables helpers
The network address was being set to 192.168.122.0 instead
of 192.168.122.0/24. Fix this by removing the unneccessary
'network' field from virNetworkDef and just pass the
network address and netmask into the iptables APIs directly.

* src/conf/network_conf.h, src/conf/network_conf.c: Remove
  the 'network' field from virNEtworkDef.
* src/network/bridge_driver.c: Update for iptables API changes
* src/util/iptables.c, src/util/iptables.h: Require the
  network address + netmask pair to be passed in
2010-10-26 11:19:13 +01:00
Philipp Hahn
f3f7a87d03 Fix documentation for virEventAddTimeout()
* src/util/event.h: Fix copy&paste error from virEventAddHandle()
2010-10-26 10:23:03 +02:00
Eric Blake
24a2663f70 dnsmasq: avoid potential crash
* src/util/dnsmasq.c (hostsfileAdd): Don't free uninitialized
memory on allocation failure.
2010-10-22 10:22:20 -06:00
Daniel P. Berrange
090404acfe Convert virNetwork to use virSocketAddr everywhere
Instead of storing the IP address string in virNetwork related
structs, store the parsed virSocketAddr. This will make it
easier to add IPv6 support in the future, by letting driver
code directly check what address family is present

* src/conf/network_conf.c, src/conf/network_conf.h,
  src/network/bridge_driver.c: Convert to use virSocketAddr
  in virNetwork, instead of char *.
* src/util/bridge.c, src/util/bridge.h,
  src/util/dnsmasq.c, src/util/dnsmasq.h,
  src/util/iptables.c, src/util/iptables.h: Convert to
  take a virSocketAddr instead of char * for any IP
  address parameters
* src/util/network.h: Add macros to determine if an address
  is set, and what address family is set.
2010-10-22 12:07:02 +01:00
Daniel P. Berrange
4b16b9c77f Include socket address in client probe data
It is useful to know where the client is connecting from,
so include the socket address in probe data.

* daemon/libvirtd.h: Use virSocketAddr for storing client
  address and keep printable address handy for logging
* daemon/libvirtd.c: Include socket address in client
  connect/disconnect probes
* daemon/probes.d: Add socket address to probes
* examples/systemtap/client.stp: Print socket address
* src/util/network.h: Add sockaddr_un to virSocketAddr union
2010-10-22 12:00:45 +01:00
Daniel P. Berrange
a8ae7d19f4 Remove all use of inet_pton and inet_ntop
The  inet_pton and inet_ntop functions are obsolete, replaced
by getaddrinfo+getnameinfo with the AI_NUMERICHOST flag set.
These can be accessed via the virSocket APIs.

The bridge.c code had methods for fetching the IP address of
a bridge which used inet_ntop. Aside from the use of inet_ntop
these methods are broken, because a NIC can have multiple
addresses and this only returns one address. Since the methods
are never used, just remove them.

* src/conf/network_conf.c, src/nwfilter/nwfilter_learnipaddr.c:
  Replace inet_pton and inet_ntop with virSocket APIs
* src/util/bridge.c, src/util/bridge.h: Remove unused methods
  which called inet_ntop.
2010-10-22 11:59:18 +01:00
Daniel P. Berrange
179c4be0e1 Fix error reporting for virSocketParse
The virSocketParse method was not doing any error reporting
which meant the true cause of the problem was lost. Remove
all error reporting from callers, and push it into virSocketParse

* src/util/network.c: Add error reporting to virSocketParse
* src/conf/domain_conf.c, src/conf/network_conf.c,
  src/network/bridge_driver.c: Remove error reporting in
  callers of virSocketParse
2010-10-22 11:26:29 +01:00
Daniel P. Berrange
497adba2d4 Expand virSocketFormat to be more flexible
The getnameinfo() function is more flexible than inet_ntop()
avoiding the need to if/else the code based on socket family.
Also make it support UNIX socket addrs and allow inclusion
of a port (service) address. Finally do proper error reporting
via normal APIs.

* src/conf/domain_conf.c, src/nwfilter/nwfilter_ebiptables_driver.c,
  src/qemu/qemu_conf.c: Fix error handling with virSocketFormat
* src/util/network.c: Rewrite virSocketFormat to use getnameinfo
  and cope with UNIX socket addrs.
2010-10-22 11:24:12 +01:00
Daniel P. Berrange
f4b54aa027 Fix netmask checks for IPv6 in virSocketCheckNetmask
There was a typo in the IPv6 path of virSocketCheckNetmask which
caused it to never execute.

* src/util/network.c: s/AF_INET/AF_INET6/ in virSocketCheckNetmask
2010-10-22 11:16:42 +01:00
Daniel P. Berrange
746c336495 Fix passing of address family to virSocketParseAddr
The virSocketParseAddr function was accepting any AF_* constant
and using that to set the ai_flags field in struct addrinfo.
This is invalid, since address families must go in the ai_family
field of the struct.

* src/util/network.c: Fix handling of address family
* src/conf/network_conf.c, src/network/bridge_driver.c: Pass
  AF_UNSPEC instead of relying on it being 0.
2010-10-22 11:16:37 +01:00
Daniel P. Berrange
af3d4eec0d Include length with virSocketAddr data
Some operations on socket addresses need to know the length of
the sockaddr struct for the particular address family. This
info was being discarded when passing around virSocketAddr
instances. Turn it from a union into a struct containing
union+socklen_t fields, so length is always kept around.

* src/util/network.h: Add socklen_t field to virSocketAddr
* src/util/network.c, src/network/bridge_driver.c,
  src/conf/domain_conf.c: Update to take account of new
  struct definition.
2010-10-22 11:15:36 +01:00
Eric Blake
f1eb9ed954 audit: simplify declaration
* src/util/virtaudit.c (virAuditSend): one less ifdef, since gcc
does not care if an ATTRIBUTE_UNUSED var gets used in some paths.
2010-10-20 12:21:52 -06:00
Matthias Bolte
83e5711418 Fix compile errors in remote.c and newly added audit code 2010-10-19 19:01:26 +02:00
Daniel P. Berrange
8f680ad3b8 Basic framework for auditing integration
Integrate with libaudit.so for auditing of important operations.
libvirtd gains a couple of config entries for auditing. By
default it will enable auditing, if its enabled on the host.
It can be configured to force exit if auditing is disabled
on the host. It will can also send audit messages via libvirt
internal logging API

Places requiring audit reporting can use the VIR_AUDIT
macro to report data. This is a no-op unless auditing is
enabled

* autobuild.sh, mingw32-libvirt.spec.in: Disable audit
  on mingw
* configure.ac: Add check for libaudit
* daemon/libvirtd.aug, daemon/libvirtd.conf,
  daemon/test_libvirtd.aug, daemon/libvirtd.c: Add config
  options to enable auditing
* include/libvirt/virterror.h, src/util/virterror.c: Add
  VIR_FROM_AUDIT source
* libvirt.spec.in: Enable audit
* src/util/virtaudit.h, src/util/virtaudit.c: Simple internal
  API for auditing messages
2010-10-19 17:31:31 +01:00
Stefan Berger
f04de501bc Introduce VIR_CLOSE to be used rather than close()
Since bugs due to double-closed file descriptors are difficult to track down in a multi-threaded system, I am introducing the VIR_CLOSE(fd) macro to help avoid mistakes here.

There are lots of places where close() is being used. In this patch I am only cleaning up usage of close() in src/conf where the problems were.

I also dare to declare close() as being deprecated in libvirt code base (HACKING).
2010-10-19 10:23:51 -04:00
Daniel Veillard
0df671513d Fixes for documentation extraction
* include/libvirt/libvirt.h.in: some of the function type description
  were broken so they could not be automatically documented
* src/util/event.c docs/apibuild.py: event.c exports one public API
  so it needs to be scanned too, avoid a few warnings
2010-10-13 13:50:07 +02:00
Nikunj A. Dadhania
5f481e4df1 Implement cgroup memory controller tunables
Provides interfaces for setting/getting memory tunables like hard_limit,
soft_limit and swap_hard_limit
2010-10-12 19:26:09 +02:00
Eric Blake
76d87a5959 maint: update to latest gnulib
* .gnulib: Update to latest.
* bootstrap.conf (gnulib_modules): Add new termios module.
(gnulib_tool_option_extras): Make libtool usage explicit.
* src/util/util.c (includes): Gnulib now guarantees termios.h.
* bootstrap: Resync from gnulib.
2010-09-23 08:15:16 -06:00
Matthias Bolte
0f9c246028 esx: Allow '-' in VMX entry names
Add a test for this.

Reported by Frank Dirks.
2010-09-23 10:37:10 +02:00
Chris Wright
12172d18ce pciFindStubDriver should return NULL on error
pciFindStubDriver currently returns 0 in one of the error cases.
While it's correct...NULL is more readable.

Signed-off-by: Chris Wright <chrisw@redhat.com>
2010-09-22 17:22:09 -06:00
Eric Blake
8ae354f41b build: avoid non-portable IPv6 struct member, for MacOS X
* src/util/network.c (getIPv6Addr): Manually join s6_addr bytes,
instead of assuming s6_addr16 shorts.
Reported by Justin Clifton; solution suggested by Bruno Haible.
2010-09-15 14:50:51 -06:00
Cole Robinson
18af6f4e64 buf: Fix possible infinite loop in EscapeString, VSnprintf
The current code will go into an infinite loop if the printf generated
string is >= 1000, AND exactly 1 character smaller than the amount of free
space in the buffer. When this happens, we are dropped into the loop body,
but nothing will actually change, because count == (buf->size - buf->use - 1),
and virBufferGrow returns unchanged if count < (buf->size - buf->use)

Fix this by removing the '- 1' bit from 'size'. The *nprintf functions handle
the NULL byte for us anyways, so we shouldn't need to manually accommodate
for it.

Here's a bug where we are actually hitting this issue:
https://bugzilla.redhat.com/show_bug.cgi?id=602772

v2: Eric's improvements: while -> if (), remove extra va_list variable,
    make sure we report buffer error if snprintf fails

v3: Add tests/virbuftest which reproduces the infinite loop before this
    patch, works correctly after
2010-09-10 10:05:43 -04:00
Matthias Bolte
1fe2927a34 Move hextobin as virHexToBin to util.c
virHexToBin will be used in the .vmx handling code.
2010-08-30 22:21:54 +02:00
Soren Hansen
4358f76aa4 Close fd's of persistent tap devices
When passing a NULL tapfd argument to brAddTap, we need to close the fd
of the tap device. If we don't, libvirt will keep the fd open
indefinitely and renders the the guest unable to configure its side of
the tap device.

Signed-off-by: Soren Hansen <soren@linux2go.dk>
2010-08-14 10:48:16 -06:00
Stefan Berger
18b6323ab9 Fix valgrind complaints when using kill -SIGHUP on libvirtd
This patch fixes a couple of complaints from valgrind when tickling libvirtd with SIGHUP.

The first two files contain fixes for memory leaks. The 3rd one initializes an uninitialized variable. The 4th one is another memory leak.
2010-08-12 16:30:11 -04:00
Soren Hansen
92e43e6d02 Add "ubd" to the list of disk prefixes
virDiskNameToIndex has a list of disk name prefixes that it uses in the
process of finding the disk's index. This list is missing "ubd" which
is the disk prefix used for UML domains.

Signed-off-by: Soren Hansen <soren@linux2go.dk>
2010-08-10 07:16:44 -06:00
Daniel Veillard
e9a8f3c644 Extend virSocketParseAddr() to allow a NULL result pointer
That way it can be used to verify a numeric address without storing
the details
* src/util/network.c: change virSocketParseAddr to allow a null @addr
  parameter
2010-08-10 15:00:15 +02:00
Laine Stump
fd5b15ff1a Add iptables rule to fixup DHCP response checksum.
This patch attempts to take advantage of a newly added netfilter
module to correct for a problem with some guest DHCP client
implementations when used in conjunction with a DHCP server run on the
host systems with packet checksum offloading enabled.

The problem is that, when the guest uses a RAW socket to read the DHCP
response packets, the checksum hasn't yet been fixed by the IP stack,
so it is incorrect.

The fix implemented here is to add a rule to the POSTROUTING chain of
the mangle table in iptables that fixes up the checksum for packets on
the virtual network's bridge that are destined for the bootpc port (ie
"dhcpc", ie port 68) port on the guest.

Only very new versions of iptables will have this support (it will be
in the next upstream release), so a failure to add this rule only
results in a warning message. The iptables patch is here:

  http://patchwork.ozlabs.org/patch/58525/

A corresponding kernel module patch is also required (the backend of
the iptables patch) and that will be in the next release of the
kernel.
2010-08-02 11:34:14 -04:00
Chris Lalancette
86b043ad3e Fix the ACS checking in the PCI code.
When trying to assign a PCI device to a guest, we have
to check that all bridges upstream of that device support
ACS.  That means that we have to find the parent bridge of
the current device, check for ACS, then find the parent bridge
of that device, check for ACS, etc.  As it currently stands,
the code to do this iterates through all PCI devices on the
system, looking for a device that has a range of busses that
included the current device's bus.

That check is not restrictive enough, though.  Depending on
how we iterated through the list of PCI devices, we could first
find the *topmost* bridge in the system; since it necessarily had
a range of busses including the current device's bus, we
would only ever check the topmost bridge, and not check
any of the intermediate bridges.

Note that this also caused a fairly serious bug in the
secondary bus reset code, where we could erroneously
find and reset the topmost bus instead of the inner bus.

This patch changes pciGetParentDevice() so that it first
checks if a bridge device's secondary bus exactly matches
the bus of the device we are looking for.  If it does, we've
found the correct parent bridge and we are done.  If it does not,
then we check to see if this bridge device's busses *include* the
bus of the device we care about.  If so, we mark this bridge device
as best, and go on.  If we later find another bridge device whose
busses include this device, but is more restrictive, then we
free up the previous best and mark the new one as best.  This
algorithm ensures that in the normal case we find the direct
parent, but in the case that the parent bridge secondary bus
is not exactly the same as the device, we still find the
correct bridge.

This patch was tested by me on a 4-port NIC with a
bridge without ACS (where assignment failed), a 4-port
NIC with a bridge with ACS (where assignment succeeded),
and a 2-port NIC with no bridges (where assignment
succeeded).

Signed-off-by: Chris Lalancette <clalance@redhat.com>
2010-08-02 09:54:38 -04:00
Chris Lalancette
435fa6d709 Fix DMI uuid parsing.
valgrind was complaining that virUUIDParse was depending on
an uninitialized value.  Indeed it was; virSetHostUUIDStr()
didn't initialize the dmiuuid buffer to 0's, meaning that
anything after the string read from /sys was uninitialized.
Clear out the dmiuuid buffer before use, and make sure to
always leave a \0 at the end.

Signed-off-by: Chris Lalancette <clalance@redhat.com>
2010-07-30 11:04:07 -04:00
Chris Lalancette
56b408231a Fix a potential race in pciInitDevice.
If detecting the FLR flag of a pci device fails, then we
could run into the situation of trying to close a file
descriptor twice, once in pciInitDevice() and once in pciFreeDevice().
Fix that by removing the pciCloseConfig() in pciInitDevice() and
just letting pciFreeDevice() handle it.

Thanks to Chris Wright for pointing out this problem.

While we are at it, fix an error check.  While it would actually
work as-is (since success returns 0), it's still more clear to
check for < 0 (as the rest of the code does).

Signed-off-by: Chris Lalancette <clalance@redhat.com>
2010-07-29 10:18:23 -04:00
Gerhard Stenzel
e4fb6a3c7d fix handling of PORT_PROFILE_RESPONSE_INPROGRESS netlink message
During function test of the 802.1Qbg implementation in lldpad we came
across a small problem in the handling of the netlink message
corresponding to PORT_PROFILE_RESPONSE_INPROGRESS. This should not
result in returning the default rc=1.

- src/util/macvtap.c: fix getPortProfileStatus() to return 0 in that
  case and also fix an indentation problem
2010-07-28 16:17:21 +02:00
Chris Lalancette
71e92a1575 Force FLR on for buggy SR-IOV devices.
Some buggy PCI devices actually support FLR, but
forget to advertise that fact in their PCI config space.
However, Virtual Functions on SR-IOV devices are
*required* to support FLR by the spec, so force has_flr
on if this is a virtual function.

Signed-off-by: Chris Lalancette <clalance@redhat.com>
2010-07-26 16:30:28 -04:00
Chris Wright
46bcdb960d pciResetDevice: use inactive devices to determine safe reset
When doing a PCI secondary bus reset, we must be sure that there are no
active devices on the same bus segment.  The active device tracking is
designed to only track host devices that are active in use by guests.
This ignores host devices that are actively in use by the host.  So the
current logic will reset host devices.

Switch this logic around and allow sbus reset when we are assigning all
devices behind a bridge to the same guest at guest startup or as a result
of a single attach-device command.

* src/util/pci.h: change signature of pciResetDevice to add an
  inactive devices list
* src/qemu/qemu_driver.c src/xen/xen_driver.c: use (or not) the new
  functionality of pciResetDevice() depending on the place of use
* src/util/pci.c: implement the interface and logic changes
2010-07-26 18:43:04 +02:00
Chris Wright
f4828ca353 pciSharesBusWithActive fails to find multiple devices on bus
The first conditional is always true which means the iterator will
never find another device on the same bus.

    if (dev->domain != check->domain ||
        dev->bus != check->bus ||
  ----> (check->slot == check->slot &&
         check->function == check->function)) <-----

The goal of that check is to verify that the device is either:

  in a different pci domain
  on a different bus
  is the same identical device

This means libvirt may issue a secondary bus reset when there are
devices
on that bus that actively in use by the host or another guest.

* src/util/pci.c: fix a bogus test in pciSharesBusWithActive()
2010-07-23 11:25:24 +02:00
Daniel P. Berrange
6ea90b843e Set a stable & high MAC addr for guest TAP devices on host
A Linux software bridge will assume the MAC address of the enslaved
interface with the numerically lowest MAC addr. When the bridge
changes MAC address there is a period of network blackout, so a
change should be avoided. The kernel gives TAP devices a completely
random MAC address. Occassionally the random TAP device MAC is lower
than that of the physical interface (eth0, eth1etc) that is enslaved,
causing the bridge to change its MAC.

This change sets an explicit MAC address for all TAP devices created
using the configured MAC from the XML, but with the high byte set
to 0xFE. This should ensure TAP device MACs are higher than any
physical interface MAC.

* src/qemu/qemu_conf.c, src/uml/uml_conf.c: Pass in a MAC addr
  for the TAP device with high byte set to 0xFE
* src/util/bridge.c, src/util/bridge.h: Set a MAC when creating
  the TAP device to override random MAC
2010-07-23 10:15:04 +01:00
Laine Stump
3e0f05fc4c Change virDirCreate to return -errno on failure.
virDirCreate also previously returned 0 on success and errno on
failure. This makes it fit the recommended convention of returning 0
on success, -errno (ie a negative number) on failure.
2010-07-21 14:32:59 -04:00
Laine Stump
2ad04f7853 Change virFileOperation to return -errno (ie < 0) on error.
virFileOperation previously returned 0 on success, or the value of
errno on failure. Although there are other functions in libvirt that
use this convention, the preferred (and more common) convention is to
return 0 on success and -errno (or simply -1 in some cases) on
failure. This way the check for failure is always (ret < 0).

* src/util/util.c - change virFileOperation and virFileOperationNoFork to
                    return -errno on failure.

* src/storage/storage_backend.c, src/qemu/qemu_driver.c
  - change the hook functions passed to virFileOperation to return
    -errno on failure.
2010-07-21 14:32:35 -04:00
Daniel P. Berrange
bf80fc68ca Require format to be passed into virStorageFileGetMetadata
Require the disk image to be passed into virStorageFileGetMetadata.
If this is set to VIR_STORAGE_FILE_AUTO, then the format will be
resolved using probing. This makes it easier to control when
probing will be used

* src/qemu/qemu_driver.c, src/qemu/qemu_security_dac.c,
  src/security/security_selinux.c, src/security/virt-aa-helper.c:
  Set VIR_STORAGE_FILE_AUTO when calling virStorageFileGetMetadata.
* src/storage/storage_backend_fs.c: Probe for disk format before
  calling virStorageFileGetMetadata.
* src/util/storage_file.h, src/util/storage_file.c: Remove format
  from virStorageFileMeta struct & require it to be passed into
  method.
2010-07-19 18:25:04 +01:00
Daniel P. Berrange
c70cb0f49b Refactor virStorageFileGetMetadataFromFD to separate functionality
The virStorageFileGetMetadataFromFD did two jobs in one. First
it probed for storage type, then it extracted metadata for the
type. It is desirable to be able to separate these jobs, allowing
probing without querying metadata, and querying metadata without
probing.

To prepare for this, split out probing code into a new pair of
methods

  virStorageFileProbeFormatFromFD
  virStorageFileProbeFormat

* src/util/storage_file.c, src/util/storage_file.h,
  src/libvirt_private.syms: Introduce virStorageFileProbeFormat
  and virStorageFileProbeFormatFromFD
2010-07-19 16:29:07 +01:00
Daniel P. Berrange
779b6ea7c4 Remove 'type' field from FileTypeInfo struct
Instead of including a field in FileTypeInfo struct for the
disk format, rely on the array index matching the format.
Use verify() to assert the correct number of elements in the
array.

* src/util/storage_file.c: remove type field from FileTypeInfo
2010-07-19 15:51:02 +01:00
Daniel P. Berrange
a93402d48b Extract the backing store format as well as name, if available
When QEMU opens a backing store for a QCow2 file, it will
normally auto-probe for the format of the backing store,
rather than assuming it has the same format as the referencing
file. There is a QCow2 extension that allows an explicit format
for the backing store to be embedded in the referencing file.
This closes the auto-probing security hole in QEMU.

This backing store format can be useful for libvirt users
of virStorageFileGetMetadata, so extract this data and report
it.

QEMU does not require disk image backing store files to be in
the same format the file linkee. It will auto-probe the disk
format for the backing store when opening it. If the backing
store was intended to be a raw file this could be a security
hole, because a guest may have written data into its disk that
then makes the backing store look like a qcow2 file. If it can
trick QEMU into thinking the raw file is a qcow2 file, it can
access arbitrary files on the host by adding further backing
store links.

To address this, callers of virStorageFileGetMeta need to be
told of the backing store format. If no format is declared,
they can make a decision whether to allow format probing or
not.
2010-07-19 15:51:02 +01:00