P J P [Mon, 25 Jul 2016 12:07:18 +0000 (17:37 +0530)]
virtio: error out if guest exceeds virtqueue size
A broken or malicious guest can submit more requests than the virtqueue
size permits.
The guest can submit requests without bothering to wait for completion
and is therefore not bound by virtqueue size. This requires reusing
vring descriptors in more than one request, which is incorrect but
possible. Processing a request allocates a VirtQueueElement and
therefore causes unbounded memory allocation controlled by the guest.
Exit with an error if the guest provides more requests than the
virtqueue size permits. This bounds memory allocation and makes the
buggy guest visible to the user.
upstream-commit-id: afd9096eb1882f23929f5b5c177898ed231bac66 Reported-by: Zhenhao Hong <zhenhaohong@gmail.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Ian Jackson [Thu, 26 May 2016 15:21:56 +0000 (16:21 +0100)]
main loop: Big hammer to fix logfile disk DoS in Xen setups
Each time round the main loop, we now fstat stderr. If it is too big,
we dup2 /dev/null onto it. This is not a very pretty patch but it is
very simple, easy to see that it's correct, and has a low risk of
collateral damage.
There is no limit by default but can be adjusted by setting a new
environment variable.
This fixes CVE-2014-3672.
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com> Tested-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Set the default to 0 so that it won't affect non-xen installation. The
limit will be set by Xen toolstack.
Signed-off-by: Wei Liu <wei.liu2@citrix.com> Acked-by: Ian Jackson <ian.jackson@eu.citrix.com> Acked-by: Anthony PERARD <anthony.perard@citrix.com>
(cherry picked from commit 44a072f0de0d57c95c2212bbce02888832b7b74f)
Gerd Hoffmann [Tue, 17 May 2016 08:54:54 +0000 (10:54 +0200)]
vga: add sr_vbe register set
Commit "fd3c136 vga: make sure vga register setup for vbe stays intact
(CVE-2016-3712)." causes a regression. The win7 installer is unhappy
because it can't freely modify vga registers any more while in vbe mode.
This patch introduces a new sr_vbe register set. The vbe_update_vgaregs
will fill sr_vbe[] instead of sr[]. Normal vga register reads and
writes go to sr[]. Any sr register read access happens through a new
sr() helper function which will read from sr_vbe[] with vbe active and
from sr[] otherwise.
This way we can allow guests update sr[] registers as they want, without
allowing them disrupt vbe video modes that way.
Gerd Hoffmann [Wed, 4 May 2016 16:43:36 +0000 (17:43 +0100)]
vga: make sure vga register setup for vbe stays intact (CVE-2016-3712).
Call vbe_update_vgaregs() when the guest touches GFX, SEQ or CRT
registers, to make sure the vga registers will always have the
values needed by vbe mode. This makes sure the sanity checks
applied by vbe_fixup_regs() are effective.
Without this guests can muck with shift_control, can turn on planar
vga modes or text mode emulation while VBE is active, making qemu
take code paths meant for CGA compatibility, but with the very
large display widths and heigts settable using VBE registers.
Which is good for one or another buffer overflow. Not that
critical as they typically read overflows happening somewhere
in the display code. So guests can DoS by crashing qemu with a
segfault, but it is probably not possible to break out of the VM.
Gerd Hoffmann [Wed, 4 May 2016 16:42:24 +0000 (17:42 +0100)]
vga: factor out vga register setup
When enabling vbe mode qemu will setup a bunch of vga registers to make
sure the vga emulation operates in correct mode for a linear
framebuffer. Move that code to a separate function so we can call it
from other places too.
vga allows banked access to video memory using the window at 0xa00000
and it supports a different access modes with different address
calculations.
The VBE bochs extentions support banked access too, using the
VBE_DISPI_INDEX_BANK register. The code tries to take the different
address calculations into account and applies different limits to
VBE_DISPI_INDEX_BANK depending on the current access mode.
Which is probably effective in stopping misprogramming by accident.
But from a security point of view completely useless as an attacker
can easily change access modes after setting the bank register.
Drop the bogus check, add range checks to vga_mem_{readb,writeb}
instead.
net: pcnet: add check to validate receive data size(CVE-2015-7504)
In loopback mode, pcnet_receive routine appends CRC code to the
receive buffer. If the data size given is same as the buffer size,
the appended CRC code overwrites 4 bytes after s->buffer. Added a
check to avoid that.
Reported by: Qinghao Tang <luodalongde@gmail.com> Cc: qemu-stable@nongnu.org Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org> Signed-off-by: Jason Wang <jasowang@redhat.com>
Jason Wang [Mon, 30 Nov 2015 07:00:06 +0000 (15:00 +0800)]
pcnet: fix rx buffer overflow(CVE-2015-7512)
Backends could provide a packet whose length is greater than buffer
size. Check for this and truncate the packet to avoid rx buffer
overflow in this case.
Cc: Prasad J Pandit <pjp@fedoraproject.org> Cc: qemu-stable@nongnu.org Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com>
Gerd Hoffmann [Mon, 14 Dec 2015 08:21:23 +0000 (09:21 +0100)]
ehci: make idt processing more robust
Make ehci_process_itd return an error in case we didn't do any actual
iso transfer because we've found no active transaction. That'll avoid
ehci happily run in circles forever if the guest builds a loop out of
idts.
This is CVE-2015-8558.
Cc: qemu-stable@nongnu.org Reported-by: Qinghao Tang <luodalongde@gmail.com> Tested-by: P J P <ppandit@redhat.com> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
net: cadence_gem: check packet size in gem_recieve
While receiving packets in 'gem_receive' routine, if Frame Check
Sequence(FCS) is enabled, it copies the packet into a local
buffer without checking its size. Add check to validate packet
length against the buffer size to avoid buffer overflow.
Reported-by: Ling Liu <liuling-it@360.cn> Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org> Signed-off-by: Jason Wang <jasowang@redhat.com>
When processing NCQ commands, AHCI device emulation prepares a
NCQ transfer object; To which an aio control block(aiocb) object
is assigned in 'execute_ncq_command'. In case, when the NCQ
command is invalid, the 'aiocb' object is not assigned, and NCQ
transfer object is left as 'used'. This leads to a use after
free kind of error in 'bdrv_aio_cancel_async' via 'ahci_reset_port'.
Reset NCQ transfer object to 'unused' to avoid it.
[Maintainer edit: s/ACHI/AHCI/ in the commit message. --js]
net: ne2000: fix bounds check in ioport operations
While doing ioport r/w operations, ne2000 device emulation suffers
from OOB r/w errors. Update respective array bounds check to avoid
OOB access.
Reported-by: Ling Liu <liuling-it@360.cn> Cc: qemu-stable@nongnu.org Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org> Signed-off-by: Jason Wang <jasowang@redhat.com>
P J P [Mon, 21 Dec 2015 09:43:13 +0000 (15:13 +0530)]
scsi: initialise info object with appropriate size
While processing controller 'CTRL_GET_INFO' command, the routine
'megasas_ctrl_get_info' overflows the '&info' object size. Use its
appropriate size to null initialise it.
Reported-by: Qinghao Tang <luodalongde@gmail.com> Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org>
Message-Id: <alpine.LFD.2.20.1512211501420.22471@wniryva> Cc: qemu-stable@nongnu.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: P J P <ppandit@redhat.com>
While sending 'SetPixelFormat' messages to a VNC server,
the client could set the 'red-max', 'green-max' and 'blue-max'
values to be zero. This leads to a floating point exception in
write_png_palette while doing frame buffer updates.
Reported-by: Lian Yihan <lianyihan@360.cn> Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org> Reviewed-by: Gerd Hoffmann <kraxel@redhat.com> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Laszlo Ersek [Tue, 19 Jan 2016 13:17:20 +0000 (14:17 +0100)]
e1000: eliminate infinite loops on out-of-bounds transfer start
The start_xmit() and e1000_receive_iov() functions implement DMA transfers
iterating over a set of descriptors that the guest's e1000 driver
prepares:
- the TDLEN and RDLEN registers store the total size of the descriptor
area,
- while the TDH and RDH registers store the offset (in whole tx / rx
descriptors) into the area where the transfer is supposed to start.
Each time a descriptor is processed, the TDH and RDH register is bumped
(as appropriate for the transfer direction).
QEMU already contains logic to deal with bogus transfers submitted by the
guest:
- Normally, the transmit case wants to increase TDH from its initial value
to TDT. (TDT is allowed to be numerically smaller than the initial TDH
value; wrapping at or above TDLEN bytes to zero is normal.) The failsafe
that QEMU currently has here is a check against reaching the original
TDH value again -- a complete wraparound, which should never happen.
- In the receive case RDH is increased from its initial value until
"total_size" bytes have been received; preferably in a single step, or
in "s->rxbuf_size" byte steps, if the latter is smaller. However, null
RX descriptors are skipped without receiving data, while RDH is
incremented just the same. QEMU tries to prevent an infinite loop
(processing only null RX descriptors) by detecting whether RDH assumes
its original value during the loop. (Again, wrapping from RDLEN to 0 is
normal.)
What both directions miss is that the guest could program TDLEN and RDLEN
so low, and the initial TDH and RDH so high, that these registers will
immediately be truncated to zero, and then never reassume their initial
values in the loop -- a full wraparound will never occur.
The condition that expresses this is:
xdh_start >= s->mac_reg[XDLEN] / sizeof(desc)
i.e., TDH or RDH start out after the last whole rx or tx descriptor that
fits into the TDLEN or RDLEN sized area.
This condition could be checked before we enter the loops, but
pci_dma_read() / pci_dma_write() knows how to fill in buffers safely for
bogus DMA addresses, so we just extend the existing failsafes with the
above condition.
Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Petr Matousek <pmatouse@redhat.com> Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Cc: Prasad Pandit <ppandit@redhat.com> Cc: Michael Roth <mdroth@linux.vnet.ibm.com> Cc: Jason Wang <jasowang@redhat.com> Cc: qemu-stable@nongnu.org
RHBZ: https://bugzilla.redhat.com/show_bug.cgi?id=1296044 Signed-off-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Roger Pau Monne [Fri, 13 Nov 2015 17:38:06 +0000 (17:38 +0000)]
xen: fix usage of xc_domain_create in domain builder
Due to the addition of HVMlite and the requirement to always provide a
valid xc_domain_configuration_t, xc_domain_create now always takes an arch
domain config, which can be NULL in order to mimic previous behaviour.
Add a small stub called xen_domain_create that encapsulates the correct
call to xc_domain_create depending on the libxc version detected.
xenfb: avoid reading twice the same fields from the shared page
Reading twice the same field could give the guest an attack of
opportunity. In the case of event->type, gcc could compile the switch
statement into a jump table, effectively ending up reading the type
field multiple times.
xen/blkif: Avoid double access to src->nr_segments
src is stored in shared memory and src->nr_segments is dereferenced
twice at the end of the function. If a compiler decides to compile this
into two separate memory accesses then the size limitation could be
bypassed.
Fix it by removing the double access to src->nr_segments.
P J P [Tue, 15 Sep 2015 14:29:21 +0000 (14:29 +0000)]
net: avoid infinite loop when receiving packets(CVE-2015-5278)
Ne2000 NIC uses ring buffer of NE2000_MEM_SIZE(49152)
bytes to process network packets. While receiving packets
via ne2000_receive() routine, a local 'index' variable
could exceed the ring buffer size, leading to an infinite
loop situation.
P J P [Tue, 15 Sep 2015 14:29:00 +0000 (14:29 +0000)]
net: add checks to validate ring buffer pointers(CVE-2015-5279)
Ne2000 NIC uses ring buffer of NE2000_MEM_SIZE(49152)
bytes to process network packets. While receiving packets
via ne2000_receive() routine, a local 'index' variable
could exceed the ring buffer size, which could lead to a
memory buffer overflow. Added other checks at initialisation.
Signed-off-by: P J P <pjp@fedoraproject.org> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-id: 1441383666-6590-1-git-send-email-stefanha@redhat.com Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Peter Lieven [Mon, 30 Jun 2014 08:07:54 +0000 (10:07 +0200)]
ui/vnc: limit client_cut_text msg payload size
currently a malicious client could define a payload
size of 2^32 - 1 bytes and send up to that size of
data to the vnc server. The server would allocated
that amount of memory which could easily create an
out of memory condition.
This patch limits the payload size to 1MB max.
Please note that client_cut_text messages are currently
silently ignored.
Signed-off-by: Peter Lieven <pl@kamp.de> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Fix release_drive on unplugged devices (pci_piix3_xen_ide_unplug)
pci_piix3_xen_ide_unplug should completely unhook the unplugged
IDEDevice from the corresponding BlockBackend, otherwise the next call
to release_drive will try to detach the drive again.
Suggested-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Stefan Hajnoczi [Wed, 15 Jul 2015 17:16:59 +0000 (18:16 +0100)]
rtl8139: drop tautologous if (ip) {...} statement
The previous patch stopped using the ip pointer as an indicator that the
IP header is present. When we reach the if (ip) {...} statement we know
ip is always non-NULL.
Remove the if statement to reduce nesting.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Stefan Hajnoczi [Wed, 15 Jul 2015 17:16:58 +0000 (18:16 +0100)]
rtl8139: avoid nested ifs in IP header parsing
Transmit offload needs to parse packet headers. If header fields have
unexpected values the offload processing is skipped.
The code currently uses nested ifs because there is relatively little
input validation. The next patches will add missing input validation
and a goto label is more appropriate to avoid deep if statement nesting.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
James Harper [Thu, 30 Oct 2014 10:08:28 +0000 (10:08 +0000)]
fix off-by-one error in pci_piix3_xen_ide_unplug
Fix off-by-one error when unplugging disks, which would otherwise leave the last ATA disk plugged, with obvious consequences. Also rewrite loop to be more readable.
Kevin Wolf [Mon, 27 Jul 2015 03:42:53 +0000 (23:42 -0400)]
ide: Clear DRQ after handling all expected accesses (CVE-2015-5154)
This is additional hardening against an end_transfer_func that fails to
clear the DRQ status bit. The bit must be unset as soon as the PIO
transfer has completed, so it's better to do this in a central place
instead of duplicating the code in all commands (and forgetting it in
some).
Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Kevin Wolf [Mon, 27 Jul 2015 03:42:53 +0000 (23:42 -0400)]
ide: Check array bounds before writing to io_buffer (CVE-2015-5154)
If the end_transfer_func of a command is called because enough data has
been read or written for the current PIO transfer, and it fails to
correctly call the command completion functions, the DRQ bit in the
status register and s->end_transfer_func may remain set. This allows the
guest to access further bytes in s->io_buffer beyond s->data_end, and
eventually overflowing the io_buffer.
One case where this currently happens is emulation of the ATAPI command
START STOP UNIT.
This patch fixes the problem by adding explicit array bounds checks
before accessing the buffer instead of relying on end_transfer_func to
function correctly.
Cc: qemu-stable@nongnu.org Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Petr Matousek [Sun, 24 May 2015 08:53:44 +0000 (10:53 +0200)]
pcnet: force the buffer access to be in bounds during tx
4096 is the maximum length per TMD and it is also currently the size of
the relay buffer pcnet driver uses for sending the packet data to QEMU
for further processing. With packet spanning multiple TMDs it can
happen that the overall packet size will be bigger than sizeof(buffer),
which results in memory corruption.
Fix this by only allowing to queue maximum sizeof(buffer) bytes.
This is CVE-2015-3209.
Signed-off-by: Petr Matousek <pmatouse@redhat.com> Reported-by: Matt Tait <matttait@google.com> Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Gonglei [Wed, 10 Jun 2015 11:49:18 +0000 (11:49 +0000)]
pcnet: fix Negative array index read
s->xmit_pos maybe assigned to a negative value (-1),
but in this branch variable s->xmit_pos as an index to
array s->buffer. Let's add a check for s->xmit_pos.
Signed-off-by: Gonglei <arei.gonglei@huawei.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Jason Wang <jasowang@redhat.com> Reviewed-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Jan Beulich [Tue, 2 Jun 2015 16:08:08 +0000 (16:08 +0000)]
xen/pt: unknown PCI config space fields should be read-only
... by default. Add a per-device "permissive" mode similar to pciback's
to allow restoring previous behavior (and hence break security again,
i.e. should be used only for trusted guests).
This is part of XSA-131.
Signed-off-by: Jan Beulich <jbeulich@suse.com> Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>)
Jan Beulich [Tue, 2 Jun 2015 16:08:07 +0000 (16:08 +0000)]
xen/pt: add a few PCI config space field descriptions
Since the next patch will turn all not explicitly described fields
read-only by default, those fields that have guest writable bits need
to be given explicit descriptors.
Jan Beulich [Tue, 2 Jun 2015 16:08:07 +0000 (16:08 +0000)]
xen/pt: mark reserved bits in PCI config space fields
The adjustments are solely to make the subsequent patches work right
(and hence make the patch set consistent), namely if permissive mode
(introduced by the last patch) gets used (as both reserved registers
and reserved fields must be similarly protected from guest access in
default mode, but the guest should be allowed access to them in
permissive mode).
Jan Beulich [Tue, 2 Jun 2015 16:08:07 +0000 (16:08 +0000)]
xen/pt: mark all PCIe capability bits read-only
xen_pt_emu_reg_pcie[]'s PCI_EXP_DEVCAP needs to cover all bits as read-
only to avoid unintended write-back (just a precaution, the field ought
to be read-only in hardware).
This is a preparatory patch for XSA-131.
Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Jan Beulich [Tue, 2 Jun 2015 16:08:07 +0000 (16:08 +0000)]
xen/pt: split out calculation of throughable mask in PCI config space handling
This is just to avoid having to adjust that calculation later in
multiple places.
Note that including ->ro_mask in get_throughable_mask()'s calculation
is only an apparent (i.e. benign) behavioral change: For r/o fields it
doesn't matter > whether they get passed through - either the same flag
is also set in emu_mask (then there's no change at all) or the field is
r/o in hardware (and hence a write won't change it anyway).
This is a preparatory patch for XSA-131.
Signed-off-by: Jan Beulich <jbeulich@suse.com> Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
Jan Beulich [Tue, 2 Jun 2015 16:08:07 +0000 (16:08 +0000)]
xen/pt: consolidate PM capability emu_mask
There's no point in xen_pt_pmcsr_reg_{read,write}() each ORing
PCI_PM_CTRL_STATE_MASK and PCI_PM_CTRL_NO_SOFT_RESET into a local
emu_mask variable - we can have the same effect by setting the field
descriptor's emu_mask member suitably right away. Note that
xen_pt_pmcsr_reg_write() is being retained in order to allow later
patches to be less intrusive.
This is a preparatory patch for XSA-131.
Signed-off-by: Jan Beulich <jbeulich@suse.com> Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Acked-by: Ian Campbell <ian.campbell@citrix.com>
Jan Beulich [Tue, 2 Jun 2015 16:08:06 +0000 (16:08 +0000)]
xen/MSI: don't open-code pass-through of enable bit modifications
Without this the actual XSA-131 fix would cause the enable bit to not
get set anymore (due to the write back getting suppressed there based
on the OR of emu_mask, ro_mask, and res_mask).
Note that the fiddling with the enable bit shouldn't really be done by
qemu, but making this work right (via libxc and the hypervisor) will
require more extensive changes, which can be postponed until after the
security issue got addressed.
This is a preparatory patch for XSA-131.
Signed-off-by: Jan Beulich <jbeulich@suse.com> Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Jan Beulich [Tue, 2 Jun 2015 16:08:06 +0000 (16:08 +0000)]
xen/MSI-X: limit error messages
Limit error messages resulting from bad guest behavior to avoid allowing
the guest to cause the control domain's disk to fill.
The first message in pci_msix_write() can simply be deleted, as this
is indeed bad guest behavior, but such out of bounds writes don't
really need to be logged.
The second one is more problematic, as there guest behavior may only
appear to be wrong: For one, the old logic didn't take the mask-all bit
into account. And then this shouldn't depend on host device state (i.e.
the host may have masked the entry without the guest having done so).
Plus these writes shouldn't be dropped even when an entry is unmasked.
Instead, if they can't be made take effect right away, they should take
effect on the next unmasking or enabling operation - the specification
explicitly describes such caching behavior. Until we can validly drop
the message (implementing such caching/latching behavior), issue the
message just once per MSI-X table entry.
Note that the log message in pci_msix_read() similar to the one being
removed here is not an issue: "addr" being of unsigned type, and the
maximum size of the MSI-X table being 32k, entry_nr simply can't be
negative and hence the conditonal guarding issuing of the message will
never be true.
This is XSA-130.
Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Jan Beulich [Tue, 2 Jun 2015 16:08:06 +0000 (16:08 +0000)]
xen: don't allow guest to control MSI mask register
It's being used by the hypervisor. For now simply mimic a device not
capable of masking, and fully emulate any accesses a guest may issue
nevertheless as simple reads/writes without side effects.
This is XSA-129.
Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Jan Beulich [Tue, 2 Jun 2015 16:08:06 +0000 (16:08 +0000)]
xen: properly gate host writes of modified PCI CFG contents
The old logic didn't work as intended when an access spanned multiple
fields (for example a 32-bit access to the location of the MSI Message
Data field with the high 16 bits not being covered by any known field).
Remove it and derive which fields not to write to from the accessed
fields' emulation masks: When they're all ones, there's no point in
doing any host write.
This fixes a secondary issue at once: We obviously shouldn't make any
host write attempt when already the host read failed.
This is XSA-128.
Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Petr Matousek [Wed, 6 May 2015 07:48:59 +0000 (09:48 +0200)]
fdc: force the fifo access to be in bounds of the allocated buffer
During processing of certain commands such as FD_CMD_READ_ID and
FD_CMD_DRIVE_SPECIFICATION_COMMAND the fifo memory access could
get out of bounds leading to memory corruption with values coming
from the guest.
Fix this by making sure that the index is always bounded by the
allocated memory.
This is CVE-2015-3456.
Signed-off-by: Petr Matousek <pmatouse@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com>
Jan Beulich [Tue, 31 Mar 2015 14:14:36 +0000 (14:14 +0000)]
xen: limit guest control of PCI command register
Otherwise the guest can abuse that control to cause e.g. PCIe
Unsupported Request responses (by disabling memory and/or I/O decoding
and subsequently causing [CPU side] accesses to the respective address
ranges), which (depending on system configuration) may be fatal to the
host.
This is CVE-2015-2756 / XSA-126.
Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Acked-by: Ian Campbell <ian.campbell@citrix.com>
Stefan Hajnoczi [Thu, 5 Mar 2015 11:27:26 +0000 (11:27 +0000)]
dmg: sanitize chunk length and sectorcount (CVE-2014-0145)
Chunk length and sectorcount are used for decompression buffers as well
as the bdrv_pread() count argument. Ensure that they have reasonable
values so neither memory allocation nor conversion from uint64_t to int
will cause problems.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Both compressed and uncompressed I/O is buffered. dmg_open() calculates
the maximum buffer size needed from the metadata in the image file.
There is currently a buffer overflow since ->lengths[] is accounted
against the maximum compressed buffer size but actually uses the
uncompressed buffer:
switch (s->types[chunk]) {
case 1: /* copy */
ret = bdrv_pread(bs->file, s->offsets[chunk],
s->uncompressed_chunk, s->lengths[chunk]);
We must account against the maximum uncompressed buffer size for type=1
chunks.
This patch fixes the maximum buffer size calculation to take into
account the chunk type. It is critical that we update the correct
maximum since there are two buffers ->compressed_chunk and
->uncompressed_chunk.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Kevin Wolf [Thu, 5 Mar 2015 11:11:27 +0000 (11:11 +0000)]
bochs: Use unsigned variables for offsets and sizes (CVE-2014-0147)
Gets us rid of integer overflows resulting in negative sizes which
aren't correctly checked.
Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Kevin Wolf [Thu, 5 Mar 2015 11:02:39 +0000 (11:02 +0000)]
qcow1: Validate image size (CVE-2014-0223)
A huge image size could cause s->l1_size to overflow. Make sure that
images never require a L1 table larger than what fits in s->l1_size.
This cannot only cause unbounded allocations, but also the allocation of
a too small L1 table, resulting in out-of-bounds array accesses (both
reads and writes).
Cc: qemu-stable@nongnu.org Signed-off-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Kevin Wolf [Thu, 5 Mar 2015 10:59:35 +0000 (10:59 +0000)]
qcow1: Validate L2 table size (CVE-2014-0222)
Too large L2 table sizes cause unbounded allocations. Images actually
created by qemu-img only have 512 byte or 4k L2 tables.
To keep things consistent with cluster sizes, allow ranges between 512
bytes and 64k (in fact, down to 1 entry = 8 bytes is technically
working, but L2 table sizes smaller than a cluster don't make a lot of
sense).
This also means that the number of bytes on the virtual disk that are
described by the same L2 table is limited to at most 8k * 64k or 2^29,
preventively avoiding any integer overflows.
Cc: qemu-stable@nongnu.org Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Benoit Canet <benoit@irqsave.net> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Kevin Wolf [Thu, 5 Mar 2015 10:52:50 +0000 (10:52 +0000)]
qcow2: Don't rely on free_cluster_index in alloc_refcount_block() (CVE-2014-0147)
free_cluster_index is only correct if update_refcount() was called from
an allocation function, and even there it's brittle because it's used to
protect unfinished allocations which still have a refcount of 0 - if it
moves in the wrong place, the unfinished allocation can be corrupted.
So not using it any more seems to be a good idea. Instead, use the
first requested cluster to do the calculations. Return -EAGAIN if
unfinished allocations could become invalid and let the caller restart
its search for some free clusters.
The context of creating a snapsnot is one situation where
update_refcount() is called outside of a cluster allocation. For this
case, the change fixes a buffer overflow if a cluster is referenced in
an L2 table that cannot be represented by an existing refcount block.
(new_table[refcount_table_index] was out of bounds)
[Bump the qemu-iotests 026 refblock_alloc.write leak count from 10 to
11.
--Stefan]
Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Kevin Wolf [Thu, 5 Mar 2015 10:42:00 +0000 (10:42 +0000)]
qcow2: Fix NULL dereference in qcow2_open() error path (CVE-2014-0146)
The qcow2 code assumes that s->snapshots is non-NULL if s->nb_snapshots
!= 0. By having the initialisation of both fields separated in
qcow2_open(), any error occuring in between would cause the error path
to dereference NULL in qcow2_free_snapshots() if the image had any
snapshots.
Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Kevin Wolf [Thu, 5 Mar 2015 10:38:10 +0000 (10:38 +0000)]
qcow2: Fix L1 allocation size in qcow2_snapshot_load_tmp() (CVE-2014-0145)
For the L1 table to loaded for an internal snapshot, the code allocated
only enough memory to hold the currently active L1 table. If the
snapshot's L1 table is actually larger than the current one, this leads
to a buffer overflow.
Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Petr Matousek [Mon, 27 Oct 2014 11:41:44 +0000 (12:41 +0100)]
vnc: sanitize bits_per_pixel from the client
bits_per_pixel that are less than 8 could result in accessing
non-initialized buffers later in the code due to the expectation
that bytes_per_pixel value that is used to initialize these buffers is
never zero.
To fix this check that bits_per_pixel from the client is one of the
values that the rfb protocol specification allows.
This is CVE-2014-7815.
Signed-off-by: Petr Matousek <pmatouse@redhat.com>
[ kraxel: apply codestyle fix ]
Gerd Hoffmann [Wed, 4 Mar 2015 17:55:51 +0000 (17:55 +0000)]
vmware-vga: CVE-2014-3689: turn off hw accel
Quick & easy stopgap for CVE-2014-3689: We just compile out the
hardware acceleration functions which lack sanity checks. Thankfully
we have capability bits for them (SVGA_CAP_RECT_COPY and
SVGA_CAP_RECT_FILL), so guests should deal just fine, in theory.
Subsequent patches will add the missing checks and re-enable the
hardware acceleration emulation.
Petr Matousek [Thu, 18 Sep 2014 06:35:37 +0000 (08:35 +0200)]
slirp: udp: fix NULL pointer dereference because of uninitialized socket
When guest sends udp packet with source port and source addr 0,
uninitialized socket is picked up when looking for matching and already
created udp sockets, and later passed to sosendto() where NULL pointer
dereference is hit during so->slirp->vnetwork_mask.s_addr access.
Fix this by checking that the socket is not just a socket stub.
This is CVE-2014-3640.
Signed-off-by: Petr Matousek <pmatouse@redhat.com> Reported-by: Xavier Mehrenberger <xavier.mehrenberger@airbus.com> Reported-by: Stephane Duverger <stephane.duverger@eads.net> Reviewed-by: Jan Kiszka <jan.kiszka@siemens.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Michael Tokarev <mjt@tls.msk.ru>
Message-id: 20140918063537.GX9321@dhcp-25-225.brq.redhat.com Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Related spice-only bug. We have a fixed 16 MB buffer here, being
presented to the spice-server as qxl video memory in case spice is
used with a non-qxl card. It's also used with qxl in vga mode.
When using display resolutions requiring more than 16 MB of memory we
are going to overflow that buffer. In theory the guest can write,
indirectly via spice-server. The spice-server clears the memory after
setting a new video mode though, triggering a segfault in the overflow
case, so qemu crashes before the guest has a chance to do something
evil.
Fix that by switching to dynamic allocation for the buffer.
Gerd Hoffmann [Wed, 4 Mar 2015 17:49:25 +0000 (17:49 +0000)]
vbe: rework sanity checks
Plug a bunch of holes in the bochs dispi interface parameter checking.
Add a function doing verification on all registers. Call that
unconditionally on every register write. That way we should catch
everything, even changing one register affecting the valid range of
another register.
Some of the holes have been added by commit e9c6149f6ae6873f14a12eea554925b6aa4c4dec. Before that commit the
maximum possible framebuffer (VBE_DISPI_MAX_XRES * VBE_DISPI_MAX_YRES *
32 bpp) has been smaller than the qemu vga memory (8MB) and the checking
for VBE_DISPI_MAX_XRES + VBE_DISPI_MAX_YRES + VBE_DISPI_MAX_BPP was ok.
Some of the holes have been there forever, such as
VBE_DISPI_INDEX_X_OFFSET and VBE_DISPI_INDEX_Y_OFFSET register writes
lacking any verification.
Security impact:
(1) Guest can make the ui (gtk/vnc/...) use memory rages outside the vga
frame buffer as source -> host memory leak. Memory isn't leaked to
the guest but to the vnc client though.
(2) Qemu will segfault in case the memory range happens to include
unmapped areas -> Guest can DoS itself.
The guest can not modify host memory, so I don't think this can be used
by the guest to escape.
Correct post load checks:
1. dev->setup_len == sizeof(dev->data_buf)
seems fine, no need to fail migration
2. When state is DATA, passing index > len
will cause memcpy with negative length,
resulting in heap overflow
First of the issues was reported by dgilbert.
Reported-by: "Dr. David Alan Gilbert" <dgilbert@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
Benoît Canet [Wed, 4 Mar 2015 17:17:12 +0000 (17:17 +0000)]
ide: Correct improper smart self test counter reset in ide core.
The SMART self test counter was incorrectly being reset to zero,
not 1. This had the effect that on every 21st SMART EXECUTE OFFLINE:
* We would write off the beginning of a dynamically allocated buffer
* We forgot the SMART history
Fix this.
Signed-off-by: Benoit Canet <benoit@irqsave.net>
Message-id: 1397336390-24664-1-git-send-email-benoit.canet@irqsave.net Reviewed-by: Markus Armbruster <armbru@redhat.com> Cc: qemu-stable@nongnu.org Acked-by: Kevin Wolf <kwolf@redhat.com>
[PMM: tweaked commit message as per suggestions from Markus] Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Malformed input can have config_len in migration stream
exceed the array size allocated on destination, the
result will be heap overflow.
To fix, that config_len matches on both sides.
CVE-2014-0182
Reported-by: "Dr. David Alan Gilbert" <dgilbert@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
When VM guest programs multicast addresses for
a virtio net card, it supplies a 32 bit
entries counter for the number of addresses.
These addresses are read into tail portion of
a fixed macs array which has size MAC_TABLE_ENTRIES,
at offset equal to in_use.
To avoid overflow of this array by guest, qemu attempts
to test the size as follows:
- if (in_use + mac_data.entries <= MAC_TABLE_ENTRIES) {
however, as mac_data.entries is uint32_t, this sum
can overflow, e.g. if in_use is 1 and mac_data.entries
is 0xffffffff then in_use + mac_data.entries will be 0.
Qemu will then read guest supplied buffer into this
memory, overflowing buffer on heap.
CVE-2014-0150
Cc: qemu-stable@nongnu.org Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-id: 1397218574-25058-1-git-send-email-mst@redhat.com Reviewed-by: Michael Tokarev <mjt@tls.msk.ru> Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Michael Roth [Wed, 4 Mar 2015 16:57:44 +0000 (16:57 +0000)]
virtio: avoid buffer overrun on incoming migration
CVE-2013-6399
vdev->queue_sel is read from the wire, and later used in the
emulation code as an index into vdev->vq[]. If the value of
vdev->queue_sel exceeds the length of vdev->vq[], currently
allocated to be VIRTIO_PCI_QUEUE_MAX elements, subsequent PIO
operations such as VIRTIO_PCI_QUEUE_PFN can be used to overrun
the buffer with arbitrary data originating from the source.
Fix this by failing migration if the value from the wire exceeds
VIRTIO_PCI_QUEUE_MAX.
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Juan Quintela <quintela@redhat.com>
Note: this adds security checks within assert calls since
SCSIBusInfo's load_request cannot fail.
For now simply disable builds with NDEBUG - there seems
to be little value in supporting these.
Cc: Andreas Färber <afaerber@suse.de> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
usb: sanity check setup_index+setup_len in post_load
CVE-2013-4541
s->setup_len and s->setup_index are fed into usb_packet_copy as
size/offset into s->data_buf, it's possible for invalid state to exploit
this to load arbitrary data.
setup_len and setup_index should be checked to make sure
they are not negative.
Cc: Gerd Hoffmann <kraxel@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Gerd Hoffmann <kraxel@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Both virtio-block and virtio-serial read,
VirtQueueElements are read in as buffers, and passed to
virtqueue_map_sg(), where num_sg is taken from the wire and can force
writes to indicies beyond VIRTQUEUE_MAX_SIZE.
To fix, validate num_sg.
Reported-by: Michael Roth <mdroth@linux.vnet.ibm.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Cc: Amit Shah <amit.shah@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
hpet is a VARRAY with a uint8 size but static array of 32
To fix, make sure num_timers is valid using VMSTATE_VALID hook.
Reported-by: Anthony Liguori <anthony@codemonkey.ws> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
r->buf is hardcoded to 2056 which is (256 + 1) * 8, allowing 256 luns at
most. If more than 256 luns are specified by user, we have buffer
overflow in scsi_target_emulate_report_luns.
To fix, we allocate the buffer dynamically.
Signed-off-by: Asias He <asias@redhat.com> Tested-by: Michael Roth <mdroth@linux.vnet.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
virtio: out-of-bounds buffer write on invalid state load
CVE-2013-4151 QEMU 1.0 out-of-bounds buffer write in
virtio_load@hw/virtio/virtio.c
So we have this code since way back when:
num = qemu_get_be32(f);
for (i = 0; i < num; i++) {
vdev->vq[i].vring.num = qemu_get_be32(f);
array of vqs has size VIRTIO_PCI_QUEUE_MAX, so
on invalid input this will write beyond end of buffer.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com> Signed-off-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
and read to the n->mac_table.in_use size buffer n->mac_table.in_use *
ETH_ALEN bytes, corrupting memory.
If adversary controls state then memory written there is controlled
by adversary.
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
with good in_use value, "n->mac_table.in_use * ETH_ALEN" can get
positive and bigger than mac_table.macs. For example 0x81000000
satisfies this condition when ETH_ALEN is 6.
Fix it by making the value unsigned.
For consistency, change first_multi as well.
Note: all call sites were audited to confirm that
making them unsigned didn't cause any issues:
it turns out we actually never do math on them,
so it's easy to validate because both values are
always <= MAC_TABLE_ENTRIES.
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Laszlo Ersek <lersek@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
Conflicts:
include/hw/virtio/virtio-net.h
Stefan Hajnoczi [Wed, 13 Feb 2013 08:25:34 +0000 (09:25 +0100)]
block/curl: only restrict protocols with libcurl>=7.19.4
The curl_easy_setopt(state->curl, CURLOPT_PROTOCOLS, ...) interface was
introduced in libcurl 7.19.4. Therefore we cannot protect against
CVE-2013-0249 when linking against an older libcurl.
Reported-by: Andreas Färber <afaerber@suse.de> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Tested-by: Andreas Färber <andreas.faeber@web.de>
Message-id: 1360743934-8337-1-git-send-email-stefanha@redhat.com Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Stefan Hajnoczi [Fri, 8 Feb 2013 07:49:10 +0000 (08:49 +0100)]
block/curl: disable extra protocols to prevent CVE-2013-0249
There is a buffer overflow in libcurl POP3/SMTP/IMAP. The workaround is
simple: disable extra protocols so that they cannot be exploited. Full
details here:
http://curl.haxx.se/docs/adv_20130206.html
QEMU only cares about HTTP, HTTPS, FTP, FTPS, and TFTP. I have tested
that this fix prevents the exploit on my host with
libcurl-7.27.0-5.fc18.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Roger Pau Monne [Mon, 17 Nov 2014 15:00:52 +0000 (15:00 +0000)]
xen_disk: fix unmapping of persistent grants
This patch fixes two issues with persistent grants and the disk PV backend
(Qdisk):
- Keep track of memory regions where persistent grants have been mapped
since we need to unmap them as a whole. It is not possible to unmap a
single grant if it has been batch-mapped. A new check has also been added
to make sure persistent grants are only used if the whole mapped region
can be persistently mapped in the batch_maps case.
- Unmap persistent grants before switching to the closed state, so the
frontend can also free them.
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Release-Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reported-by: George Dunlap <george.dunlap@eu.citrix.com> Cc: Kevin Wolf <kwolf@redhat.com> Cc: Stefan Hajnoczi <stefanha@redhat.com> Cc: George Dunlap <george.dunlap@eu.citrix.com>
Matthew Daley [Thu, 10 Oct 2013 14:15:47 +0000 (14:15 +0000)]
xen_disk: mark ioreq as mapped before unmapping in error case
Commit 4472beae modified the semantics of ioreq_{un,}map so that they are
idempotent if called when they're not needed (ie., twice in a row). However,
it neglected to handle the case where batch mapping is not being used (the
default), and one of the grants fails to map. In this case, ioreq_unmap will
be called to unwind and unmap any mappings already performed, but ioreq_unmap
simply returns due to the aforementioned change (the ioreq has not already
been marked as mapped).
The frontend user can therefore force xen_disk to leak grant mappings, a
per-domain limited resource.
Fix by marking the ioreq as mapped before calling ioreq_unmap in this
situation.
Signed-off-by: Matthew Daley <mattjd@gmail.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
In addition, at least all files created with the "guest-file-open" QMP
command, and all files created with shell output redirection (or
otherwise) by utilities invoked by the fsfreeze hook script are affected.
For now mask all file mode bits for "group" and "others" in
become_daemon().
Temporarily, for compatibility reasons, stick with the 0666 file-mode in
case of files newly created by the "guest-file-open" QMP call. Do so
without changing the umask temporarily.
Currently the qemu-nbd program will auto-detect the format of
any disk it is given. This behaviour is known to be insecure.
For example, if qemu-nbd initially exposes a 'raw' file to an
unprivileged app, and that app runs
then the next time the app is started, the qemu-nbd will now
detect it as a 'qcow2' file and expose /etc/shadow to the
unprivileged app.
The only way to avoid this is to explicitly tell qemu-nbd what
disk format to use on the command line, completely disabling
auto-detection. This patch adds a '-f' / '--format' arg for
this purpose, mirroring what is already available via qemu-img
and qemu commands.
qemu-nbd --format raw -p 9000 evil.img
will now always use raw, regardless of what format 'evil.img'
looks like it contains
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
[Use errx, not err. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Support backend option "direct-io-safe". This is documented as
follows in the Xen backend specification:
* direct-io-safe
* Values: 0/1 (boolean)
* Default Value: 0
*
* The underlying storage is not affected by the direct IO memory
* lifetime bug. See:
* http://lists.xen.org/archives/html/xen-devel/2012-12/msg01154.html
*
* Therefore this option gives the backend permission to use
* O_DIRECT, notwithstanding that bug.
*
* That is, if this option is enabled, use of O_DIRECT is safe,
* in circumstances where we would normally have avoided it as a
* workaround for that bug. This option is not relevant for all
* backends, and even not necessarily supported for those for
* which it is relevant. A backend which knows that it is not
* affected by the bug can ignore this option.
*
* This option doesn't require a backend to use O_DIRECT, so it
* should not be used to try to control the caching behaviour.
Also, BDRV_O_NATIVE_AIO is ignored if BDRV_O_NOCACHE, so clarify the
default flags passed to the qemu block layer.
The original proposal for a "cache" backend option has been dropped
because it was believed too wide, especially considering that at the
moment the backend doesn't have a way to tell the toolstack that it is
capable of supporting it.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Igor Mammedov [Thu, 25 Apr 2013 14:05:25 +0000 (16:05 +0200)]
acpi_piix4: Add infrastructure to send CPU hot-plug GPE to guest
* introduce processor status bitmask visible to guest at 0xaf00 addr,
where ACPI asl code expects it
* set bit corresponding to APIC ID in processor status bitmask on
receiving CPU hot-plug notification
* trigger CPU hot-plug SCI, to notify guest about CPU hot-plug event
Signed-off-by: Igor Mammedov <imammedo@redhat.com> Signed-off-by: Andreas Färber <afaerber@suse.de>
(cherry picked from QEMU commit b8622725cf0196f672f272922b0941dc8ba1c408)
The function piix4_cpu_hotplug_req() has been modified to take an integer
instead of a CPU object.
There was a cpu_added_notifier in the original commit, this haven't
been back-ported, as it can't be used.
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Wrapper to avoid open-coded loops and to make CPUState iteration
independent of CPUArchState.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Igor Mammedov <imammedo@redhat.com> Signed-off-by: Andreas Färber <afaerber@suse.de>
(cherry picked from QEMU commit d6b9e0d60cc511eca210834428bb74508cff3d33) Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Igor Mammedov [Tue, 23 Apr 2013 08:29:41 +0000 (10:29 +0200)]
cpu: Introduce get_arch_id() method and override it for X86CPU
get_arch_id() adds possibility for generic code to get a guest-visible
CPU ID without accessing CPUArchState.
If derived classes don't override it, it will return cpu_index.
Override it on target-i386 in X86CPU to return the APIC ID.
Signed-off-by: Igor Mammedov <imammedo@redhat.com> Reviewed-by: Eduardo Habkost <ehabkost@redhat.com> Reviewed-by: liguang <lig.fnst@cn.fujitsu.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Andreas Färber <afaerber@suse.de>
(cherry picked from QEMU commit 997395d3888fcde6ce41535a8208d7aa919d824b) Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
xen: start PCI hole at 0xe0000000 (same as pc_init1 and qemu-xen-traditional)
We are currently setting the PCI hole to start at HVM_BELOW_4G_RAM_END,
that is 0xf0000000.
Start the PCI hole at 0xe0000000 instead, that is the same value used by
pc_init1 and qemu-xen-traditional.