pygrub (in identify_disk_image()) detects a DOS style partition table
via the presence of the 0xaa55 signature at the end of the first
sector of the disk.
However this signature is also present in whole-disk configurations
when there is an MBR on the disk. Many filesystems (e.g. ext[234])
include leading padding in their on disk format specifically to enable
this.
So if we think we have a DOS partition table but do not find any
actual partition table entries we may as well try looking at it as a
whole disk image. Worst case is we probe and find there isn't anything
there.
This was reported by Sjors Gielen in Debian bug #745419. The fix was
inspired by a patch by Adi Kriegisch in
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=745419#27
Tested by genext2fs'ing my /boot into a new raw image (works) and
then:
dd if=/usr/lib/grub/i386-pc/g2ldr.mbr of=img conv=notrunc bs=512 count=1
to add an MBR (with 0xaa55 signature) to it, which after this patch
also works.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Cc: 745419-forwarded@bugs.debian.org
(cherry picked from commit fb31b1475f)
(cherry picked from commit 6c9b1bcce4)
scratch_alloc() set scratch_start to the last byte of the current
allocation. The value of scratch_start is then reused as is (if it is
already aligned) in the next allocation. This result in a potential reuse
of the last byte of the previous allocation.
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
master commit: 4ab3ac074c
master date: 2016-02-10 14:46:45 +0100
ml_interface_{read,write}() would miscalculate the quantity of
data/space in the ring if it crossed the ring boundary, and incorrectly
return a short read/write.
This causes a protocol stall, as either side of the ring ends up waiting
for what they believe to be the other side needing to take the next
action.
Correct the calculations to cope with crossing the ring boundary.
In addition, correct the error detection. It is a hard error if the
producer index gets more than a ring size ahead of the consumer, or if
the consumer ever overtakes the producer.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Reviewed-by: David Scott <dave@recoil.org>
(cherry picked from commit 8a2c11f876)
(cherry picked from commit 6150df9f3f)
In Quota.merge, we merge two quota hashtables, orig_quota and mod_quota, putting
the results into dest_quota. These hashtables map domids to the number of
entries currently owned by that domain.
When mod_quota contains an entry for a domid that was not present in orig_quota
(or dest_quota), the call to get_entry caused Quota.merge to raise a Not_found
exception. This propagates back to the client as an ENOENT error, which is not
an appropriate return value from some operations, such as transaction_end.
This situation can arise when a transaction that introduces a domain (hence
calling Quota.add_entry) needs to be coalesced due to concurrent xenstore
activity.
This patch handles the merge in the case where mod_quota contains an entry not
present in orig_quota (or in dest_quota) by treating that hashtable as having
existing value 0.
Signed-off-by: Jonathan Davies <jonathan.davies@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
(cherry picked from commit 82ff7cbed6)
(cherry picked from commit ba391da2e7)
[ Cross-ported to blktap1 from 345e44a85d
"blktap2: Fix two 'maybe uninitialized' variables" -iwj;
Remainder of commit message is from blktap2's version. ]
for which gcc 4.9.0 complains about, like this:
block-qcow.c: In function `get_cluster_offset':
block-qcow.c:431:3: error: `tmp_ptr' may be used uninitialized in this function
[-Werror=maybe-uninitialized]
memcpy(tmp_ptr, l1_ptr, 4096);
^
block-qcow.c:606:7: error: `tmp_ptr2' may be used uninitialized in this
function [-Werror=maybe-uninitialized]
if (write(s->fd, tmp_ptr2, 4096) != 4096) {
^
cc1: all warnings being treated as errors
/home/dario/Sources/xen/xen/xen.git/tools/blktap2/drivers/../../../tools/Rules.mk:89:
recipe for target 'block-qcow.o' failed
make[5]: *** [block-qcow.o] Error 1
The proper behavior is to return upon allocation failure.
About what to return, 0 seems the best option, looking
at both the function and the call sites.
Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Backport-requested-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
The bootloader may call libxl__file_reference_map(), which mmap's the
pv_kernel and pv_ramdisk into process memory. This was only unmapped,
however, on the success path of libxl__build_pv(). If there were a
failure anywhere between libxl_bootloader.c:parse_bootloader_result()
and the end of libxl__build_pv(), the calls to
libxl__file_reference_unmap() would be skipped, leaking the mapped
virtual memory.
Ideally this would be fixed by adding the unmap calls to the
destruction path for libxl__domain_build_state. Unfortunately the
lifetime of the libxl__domain_build_state is opaque, and it doesn't
have a proper destruction path. But, the only thing in it that isn't
from the gc are these bootloader references, and they are only ever
set for one libxl__domain_build_state, the one which is
libxl__domain_create_state.build_state.
So we can clean up in the exit path from libxl__domain_create_*, which
always comes through domcreate_complete.
Remove the now-redundant unmaps in libxl__build_pv's success path.
This is XSA-160.
Signed-off-by: George Dunlap <george.dunlap@citrix.com>
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Tested-by: George Dunlap <george.dunlap@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
(cherry picked from commit 59543a7cc2)
PoD guests need to balloon at least as far as required by PoD, or risk
crashing. Currently they don't necessarily know what the right value
is, because our memory accounting is (at the very least) confusing.
Apply the memory limit fudge factor to the in-hypervisor PoD memory
target, too. This will increase the size of the guest's PoD cache by
the fudge factor LIBXL_MAXMEM_CONSTANT (currently 1Mby). This ensures
that even with a slightly-off balloon driver, the guest will be
stable even under memory pressure.
There are two call sites of xc_domain_set_pod_target that need fixing:
The one in libxl_set_memory_target is straightforward.
The one in xc_hvm_build_x86.c:setup_guest is more awkward. Simply
setting the PoD target differently does not work because the various
amounts of memory during domain construction no longer match up.
Instead, we adjust the guest memory target in xenstore (but only for
PoD guests).
This introduces a 1Mby discrepancy between the balloon target of a PoD
guest at boot, and the target set by an apparently-equivalent `xl
mem-set' (or similar) later. This approach is low-risk for a security
fix but we need to fix this up properly in xen.git#staging and
probably also in stable trees.
This is XSA-153.
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
(cherry picked from commit 56fb5fd623)
This reverts commit 9befcd335c.
This commit breaks the build:
libxl_arm.c: In function 'libxl__arch_domain_init_hw_description':
libxl_arm.c:591:76: error: 'state' undeclared (first use in this function)
libxl_arm.c:591:76: note: each undeclared identifier is reported only once fo\
r each function it appears in
make[3]: *** [libxl_arm.o] Error 1
"state" was introduced in a7511905 "xen: Extend DOMCTL createdomain to
support arch configuration".
On Julien's recommendation: a7511905 ought not to be backported, so
revert this and wait for Ian Campbell to get back.
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
CC: Julien Grall <julien.grall@citrix.com>
CC: Ian Campbell <Ian.Campbell@eu.citrix.com>
CC: Jan Beulich <JBeulich@suse.com>
When creating a guest with more than 3GB of memory, the 2 banks will be
used and the loop with overrunning. The code will fail later on because
Xen will deny to populate the region:
domainbuilder: detail: xc_dom_devicetree_mem: called
domainbuilder: detail: xc_dom_mem_init: mem 3096 MB, pages 0xc1800 pages, 4k each
domainbuilder: detail: xc_dom_mem_init: 0xc1800 pages
domainbuilder: detail: xc_dom_boot_mem_init: called
domainbuilder: detail: set_mode: guest xen-3.0-aarch64, address size 64
domainbuilder: detail: xc_dom_malloc : 14384 kB
domainbuilder: detail: populate_guest_memory: populating RAM @0000000040000000-0000000100000000 (3072MB)
domainbuilder: detail: populate_one_size: populated 0x3/0x3 entries with shift 18
domainbuilder: detail: populate_guest_memory: populating RAM @0000000200000000-0000000201800000 (24MB)
domainbuilder: detail: populate_one_size: populated 0xc/0xc entries with shift 9
domainbuilder: detail: populate_guest_memory: populating RAM @0000007fad41c000-0007fb39dd42c000 (2141954816MB)
domainbuilder: detail: populate_one_size: populated 0x100/0x1e4 entries with shift 0
domainbuilder: detail: populate_guest_memory: Not enough RAM
This is because we are currently accessing the bank before checking the
validity of the index. AFAICT, on Debian Jessie, the compiler (gcc 4.9.2) is
assuming that it's not necessary to verify the index because it's used
before. This is a valid assumption because the operand of && are
execute from from left to right.
Re-order the checks to verify the validity of the index before accessing
the bank.
The problem has been present since the introduction of the multi-bank
feature in commit 45d9867837 " tools: arm:
prepare domain builder for multiple banks of guest RAM".
Signed-off-by: Julien Grall <julien.grall@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
(cherry picked from commit ed5c2c05cf)
We need to use libxl__domain_build_state.pv_cmdline in order to pickup
the correct args when using pygrub. libxl_domain_build_info.cmdline is
any args statically configured by the user.
This is consistent with the call to xc_domain_allocate, which takes
the cmdline too (in that case for x86/PV usage).
state->pv_cmdline is also set for non-pygrub guests, since
libxl__bootloader_run propagates info->cmdline if no bootloader is
configured.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
(cherry picked from commit 201eac8383)
Since XSA-131 qemu-xen now restricts access to PCI cfg by default. In
order to allow local configuration of the existing libxl_device_pci
"permissive" flag needs to be plumbed through via the new QMP property
added by the XSA-131 patches.
Versions of QEMU prior to XSA-131 did not support this permissive
property, so we only pass it if it is true. Older versions only
supported permissive mode.
qemu-xen-traditional already supports the permissive mode setting via
xenstore.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: George Dunlap <george.dunlap@eu.citrix.com>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
(cherry picked from commit 015a373351)
The current libxl code doesn't deal with read-only drives at all.
Upstream QEMU and qemu-xen only support read-only cdrom drives: make
sure to specify "readonly=on" for cdrom drives and return error in case
the user requested a non-cdrom read-only drive.
This is XSA-142, discovered by Lin Liu
(https://bugzilla.redhat.com/show_bug.cgi?id=1257893).
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Backport to Xen 4.5 and earlier, apropos of report and review from
Michael Young.
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
On a busy host, QEMU may take more than 10s to load and start.
This is likely due to a bug in Linux where the I/O subsystem sometime
produce high latency under load and result in QEMU taking a long time to
load every single dynamic libraries.
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
(cherry picked from commit 9acfbe14d7)
Conflicts:
tools/libxl/libxl_internal.h
Don't dereference extra_config if it's NULL. Don't leak extra_config in
the end.
Also fixed a typo in error string while I was there.
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
(cherry picked from commit 705c9e1242)
It can happen that an fd is deregistered, and closed, and then a new
fd opened, and reregistered, all while another thread is in poll().
If this happens poll might report POLLNVAL, but the event loop would
think that the fd was supposed to have been valid, and then fail an
assertion:
libxl_event.c:1183: afterpoll_check_fd: Assertion `poller->fds_changed || !(fds[slot].revents & 0x020)' failed.
We can't simply ignore POLLNVAL because if we have bugs which cause
messed-up fds, it is a serious problem which we really need to detect.
Instead, add extra tracking to spot when this possibility arises, and
abort on POLLNVAL if we are sure that it is unexpected.
Reported-by: Jim Fehlig <jfehlig@suse.com>
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
CC: Jim Fehlig <jfehlig@suse.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Tested-by: Jim Fehlig <jfehlig@suse.com>
(cherry picked from commit 681ce16816)
This makes the code more regular. We are going to want to do some
more work in poller_get and poller_put, which work also wants to be
done for poller_app.
Two very minor functional changes:
* We call malloc an extra time since poller_app is now a pointer
* ERROR_FAIL on poller_get failing for poller_app is generated in
libxl_ctx_init rather than passed through by libxl_poller_init
from libxl__pipe_nonblock.
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
CC: Jim Fehlig <jfehlig@suse.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Tested-by: Jim Fehlig <jfehlig@suse.com>
(cherry picked from commit aae3765206)
If libxl_create_logfile fails for some reason then
libxl__create_qemu_logfile previously just carried on and dereferenced
the uninitialised logfile.
Check for the error from libxl_create_logfile, which has already
logged for us.
This was reported as Debian bug #784880.
Reported-by: Russell Coker <russell@coker.com.au>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: 784880@bugs.debian.org
Acked-by: Wei Liu <wei.liu2@citrix.com>
(cherry picked from commit e9d3a85997)
Various xl sub-commands take additional parameters containing = as
additional config fragments.
The handling of these config fragments has a number of bugs:
1. Use of a static 1024-byte buffer. (If truncation would occur,
with semi-trusted input, a security risk arises due to quotes
being lost.)
2. Mishandling of the return value from snprintf, so that if
truncation occurs, the to-write pointer is updated with the
wanted-to-write length, resulting in stack corruption. (This is
XSA-137.)
3. Clone-and-hack of the code for constructing the appended
config file.
These are fixed here, by introducing a new function
`string_realloc_append' and using it everywhere. The `extra_info'
buffers are replaced by pointers, which start off NULL and are
explicitly freed on all return paths.
The separate variable which will become dom_info.extra_config is
abolished (which involves moving the clearing of dom_info).
Additional bugs I observe, not fixed here:
4. The functions which now call string_realloc_append use ad-hoc
error returns, with multiple calls to `return'. This currently
necessitates multiple new calls to `free'.
5. Many of the paths in xl call exit(-rc) where rc is a libxl status
code. This is a ridiculous exit status `convention'.
6. The loops for handling extra config data are clone-and-hacks.
7. Once the extra config buffer is accumulated, it must be combined
with the appropriate main config file. The code to do this
combining is clone-and-hacked too.
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Tested-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Acked-by: Ian Campbell <ian,campbell@citrix.com>
(cherry picked from commit dd84604f35)
The functions ring_read and ring_write() have logic to try and deal with
partial reads and writes.
However, in all cases where the "while (len)" loop executed twice, data
corruption would occur as the second memcpy() starts from the beginning of
"data" again, rather than from where it got to.
This bug manifested itself as protocol corruption when a reply header crossed
the first wrap of the response ring. However, similar corruption would also
occur if hvmloader observed xenstored performing partial writes of the block
in question, or if hvmloader had to wait for xenstored to make space in either
ring.
Reported-by: Adam Kucia <djexit@o2.pl>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: bbbe7e7157
master date: 2015-07-07 14:39:27 +0200
There is no sense in trying to online (or offline) CPUs when the size of
cpumap is greater than the maximum number of VCPUs the guest can go to.
As such fail the operation if the count of CPUs to online is greater
than what the guest started with. For the offline case we do not
check (as the bits are unset in the cpumap) and let it go through.
We coalesce some of the underlying libxl_set_vcpuonline code
together which was duplicated in QMP and XenStore codepaths.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
(cherry picked from commit d83bf9d224)
Conflicts:
tools/libxl/libxl.c
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
libxl__ao_inprogress needs to check (like
libxl__ao_complete_check_progress_reports) that there are no
oustanding progress callbacks.
Otherwise it might happen that we would destroy the ao while another
thread has an outstanding callback its egc report queue. The other
thread would then, in its egc_run_callbacks, touch the destroyed ao.
Instead, when this happens in libxl__ao_inprogress, simply run round
the event loop again. The thread which eventually makes the callback
will spot our poller in the ao, and notify the poller, waking us up.
This fixes an assertion failure race seen with libvirt:
libvirtd: libxl_event.c:1792: libxl__ao_complete_check_progress_reports: Assertion `ao->in_initiator' failed.
or (after "Add an assert to egc_run_callbacks")
libvirtd: libxl_event.c:1338: egc_run_callbacks: Assertion `aop->ao->magic == 0xA0FACE00ul' failed.
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
CC: Ian Campbell <ian.campbell@citrix.com>
CC: Wei Liu <wei.liu2@citrix.com>
CC: Jim Fehlig <jfehlig@suse.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
(cherry picked from commit f1335f0d7b)
Break out the test in libxl__ao_complete_check_progress_reports, into
ao_work_outstanding, which reports false if either (i) the ao is still
ongoing or (ii) there is a progress report (perhaps on a different
thread's callback queue) which has yet to be reported to the
application.
No functional change.
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
CC: Ian Campbell <ian.campbell@citrix.com>
CC: Wei Liu <wei.liu2@citrix.com>
CC: Jim Fehlig <jfehlig@suse.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
(cherry picked from commit 93699882d9)
XenServer's VM density testing uncovered a regression when moving from
sysvinit to systemd where the file descriptor limit dropped from 4096 to
1024. (XenServer had previously inserted a ulimit statement into its
initscripts.)
One solution is to use LimitNOFILE=4096 in xenconsoled.service to match the
lost ulimit, but that is only a stopgap solution.
As Xenconsoled genuinely needs a large number of file descriptors if a large
number of domains are running, attempt to increase the limit.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
(cherry picked from commit 588df84c0d)
Don't kill xenstored as part of the usual service shutdown process to
prevent hangs on shutdown where the kernel tries to unplug a VIF
after xenstored has exited.
In an ideal case with all guests cooperating, xendomains will have shut
down all guests before xenstored is killed.
However in the uncooperative case, malicious or crashed guests may still
be running after xendomains has exited and this should not block the
shutdown/reboot of dom0.
Xenstored has no state to sync to disk, and never used to be killed in
the sysvinit case; observe the warning in xencommons. Our testing has
shown regressions caused by the change in behaviour between sysvinit and
systemd when it comes to killing xenstored.
Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
[ ijc -- added systemd to title ]
(cherry picked from commit 96e0ee8386)
The Ocaml stub to retrieve the hypervisor console ring had a few problems.
* A single 32k buffer would truncate a large console ring.
* The buffer was static and not under the protection of the Ocaml GC lock so
could be clobbered by concurrent accesses.
* Embedded NUL characters would cause caml_copy_string() (which is strlen()
based) to truncate the buffer.
The function is rewritten from scratch, using the same algorithm as the python
stubs, but uses the protection of the Ocaml GC lock to maintain a static
running total of the ring size, to avoid redundant realloc()ing in future
calls.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
CC: Dave Scott <dave.scott@eu.citrix.com>
CC: Ian Campbell <Ian.Campbell@citrix.com>
CC: Ian Jackson <Ian.Jackson@eu.citrix.com>
CC: Wei Liu <wei.liu2@citrix.com>
Acked-by: David Scott <dave.scott@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
(cherry picked from commit 1a010ca99e)
Call xc_domain_destroy in a subprocess. That allows us to do so
asynchronously, rather than blocking the whole process calling libxl.
The changes in detail:
* Provide an libxl__ev_child in libxl__domain_destroy_state, and
initialise it in libxl__domain_destroy. There is no possibility
to `clean up' a libxl__ev_child, but there need to clean it up, as
the control flow ensures that we only continue after the child has
exited.
* Call libxl__ev_child_fork at the right point and put the call to
xc_domain_destroy and associated logging in the child. (The child
opens a new xenctrl handle because we mustn't use the parent's.)
* Consequently, the success return path from domain_destroy_domid_cb
no longer calls dis->callback. Instead it simply returns.
* We plumb the errorno value through the child's exit status, if it
fits. This means we normally do the logging only in the parent.
* Incidentally, we fix the bug that we were treating the return value
from xc_domain_destroy as an errno value when in fact it is a
return value from do_domctl (in this case, 0 or -1 setting errno).
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Jim Fehlig <jfehlig@suse.com>
Tested-by: Jim Fehlig <jfehlig@suse.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
(cherry picked from commit 188e9c541f)
From: Ian Jackson <Ian.Jackson@eu.citrix.com>
When domain_death_xswatch_callback needed a further call to
xc_domain_getinfolist it would restart it with the last domain it
found rather than the first one it wants.
If it only wants one it will also only ask for one domain. The result
would then be that it gets the previous domain again (ie, the previous
one to the one it wants), which still doesn't reveal the answer to the
question, and it would therefore loop again.
It's completely unclear to me why I thought it was a good idea to
start the xc_domain_getinfolist with the last domain previously found
rather than the first one left un-confirmed. The code has been that
way since it was introduced.
Instead, start each xc_domain_getinfolist at the next domain whose
status we need to check.
We also need to move the test for !evg into the loop, we now need evg
to compute the arguments to getinfolist.
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Reported-by: Jim Fehlig <jfehlig@suse.com>
Reviewed-by: Jim Fehlig <jfehlig@suse.com>
Tested-by: Jim Fehlig <jfehlig@suse.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
(cherry picked from commit 4783c99aab)
CMPXCHG sets CF, PF, AF, SF, and OF flags according to the results of the
comparison the rAX with the operand of the instruction.
rAX must be the first argument of the comparison (a minuend), the operand
must be the second one (a subtrahend).
Due to improper order of comparison arguments, CF, PF, AF, SF and OF flags were
set incorrectly in the case of inequality. Need to swap them.
Signed-off-by: Eugene Korenevsky <ekorenevsky@gmail.com>
# Commit 20fd4b70a7
# Date 2015-05-04 12:03:19 +0200
# Author Eugene Korenevsky <ekorenevsky@gmail.com>
# Committer Jan Beulich <jbeulich@suse.com>
test_x86_emulate: extend EFLAGS check of CMPXCHG test
CMPXCHG: in the case of inequality of the rAX and the operand,
need to check CF, PF, AF, SF and OF flags as well.
This adjustment covers the fix of incorrect comparison during
CMPXCHG emulation.
Signed-off-by: Eugene Korenevsky <ekorenevsky@gmail.com>
master commit: 2232628ecb
master date: 2015-05-04 11:55:41 +0200
master commit: 20fd4b70a7
master date: 2015-05-04 12:03:19 +0200
Said hypercall for large BARs can take quite a while. As such
we can require that the hypercall MUST break up the request
in smaller values.
Another approach is to add preemption to it - whether we do the
preemption using hypercall_create_continuation or returning
EAGAIN to userspace (and have it re-invocate the call) - either
way the issue we cannot easily solve is that in 'map_mmio_regions'
if we encounter an error we MUST call 'unmap_mmio_regions' for the
whole BAR region.
Since the preemption would re-use input fields such as nr_mfns,
first_gfn, first_mfn - we would lose the original values -
and only undo what was done in the current round (i.e. ignoring
anything that was done prior to earlier preemptions).
Unless we re-used the return value as 'EAGAIN|nr_mfns_done<<10' but
that puts a limit (since the return value is a long) on the amount
of nr_mfns that can provided.
This patch sidesteps this problem by:
- Setting an hard limit of nr_mfns having to be 64 or less.
- Toolstack adjusts correspondingly to the nr_mfn limit.
- If the there is an error when adding the toolstack will call the
remove operation to remove the whole region.
The need to break this hypercall down is for large BARs can take
more than the guest (initial domain usually) time-slice. This has
the negative result in that the guest is locked out for a long
duration and is unable to act on any pending events.
We also augment the code to return zero if nr_mfns instead
of trying to the hypercall.
This is XSA-125 / CVE-2015-2752.
Suggested-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
By default qemu will try to create some sort of backend for the
emulated VGA device, either SDL or VNC.
However when the user specifies sdl=0 and vnc=0 in their configuration
libxl was not explicitly disabling either backend, which could lead to
one unexpectedly running.
If either sdl=1 or vnc=1 is configured then both before and after this
change only the backends which are explicitly enabled are configured,
i.e. this issue only occurs when all backends are supposed to have
been disabled.
This affects qemu-xen and qemu-xen-traditional differently.
If qemu-xen was compiled with SDL support then this would result in an
SDL window being opened if $DISPLAY is valid, or a failure to start
the guest if not. Passing "-display none" to qemu before any further
-sdl options disables this default behaviour and ensures that SDL is
only started if the libxl configuration demands it.
If qemu-xen was compiled without SDL support then qemu would instead
start a VNC server listening on ::1 (IPv6 localhost) or 127.0.0.1
(IPv4 localhost) with IPv6 preferred if available. Explicitly pass
"-vnc none" when vnc is not enabled in the libxl configuration to
remove this possibility.
qemu-xen-traditional would never start a vnc backend unless asked.
However by default it will start an SDL backend, the way to disable
this is to pass a -vnc option. In other words passing "-vnc none" will
disable both vnc and sdl by default. sdl can then be reenabled if
configured by subsequent use of the -sdl option.
Tested with both qemu-xen and qemu-xen-traditional built with SDL
support and:
xl cr # defaults
xl cr sdl=0 vnc=0
xl cr sdl=1 vnc=0
xl cr sdl=0 vnc=1
xl cr sdl=0 vnc=0 vga=\"none\"
xl cr sdl=0 vnc=0 nographic=1
with both valid and invalid $DISPLAY.
This is XSA-119 / CVE-2015-2152.
Reported-by: Sander Eikelenboom <linux@eikelenboom.it>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
(cherry picked from commit 91b0ae9db3)
c/s 5b5c40c0d1 "libxc: introduce a per architecture scratch pfn for temporary
grant mapping" accidentally an issue whereby there were two paths out of
xc_core_arch_get_scratch_gpfn() which returned 0, but only one of which
assigned a value to the gpfn parameter.
xc_domain_maximum_gpfn() can validly return 0, at which point gpfn 1 is a
valid scratch page to use.
In addition, widen rc before adding 1 and possibly overflowing.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
CC: Julien Grall <julien.grall@linaro.org>
CC: Jan Beulich <JBeulich@suse.com>
CC: Ian Campbell <Ian.Campbell@citrix.com>
CC: Ian Jackson <Ian.Jackson@eu.citrix.com>
CC: Wei Liu <wei.liu2@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
(cherry picked from commit 5b0447f647)
This has been renamed by the rumpkernels upstream.
(This patch needs to be backported.)
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
CC: Antti Kantee <pooka@iki.fi>
CC: Martin Lucina <martin@lucina.net>
CC: Ian Campbell <Ian.Campbell@eu.citrix.com>
(cherry picked from commit f4e99a4f5098f6fa3c856f79b8365bb29a3d3a15)
Starting from rump kernel changeset 91d5623 ("Renaming platform macros,
app-tools and autoconf target string"), __RUMPUSER_XEN__ and __RUMPAPP__
are deleted. We are supposed to use __RUMPRUN__ instead.
We still keep __RUMPUSER_XEN__ for now in order to make xen-unstable
pass osstest push gate. I will remove __RUMPUSER_XEN__ later.
Related discussion:
http://thread.gmane.org/gmane.comp.rumpkernel.user/739
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
(cherry picked from commit 441256a532)
The code to initialize the grant table in libxc uses
xc_domain_maximum_gpfn() + 1 to get a guest pfn for mapping the grant
frame and to initialize it.
This solution has two major issues:
- The check of the return of xc_domain_maximum_gpfn is buggy because
xen_pfn_t is unsigned and in case of an error -ERRNO is returned.
Which is never catch with ( pfn <= 0 ).
- The guest memory layout maybe filled up to the end, i.e
xc_domain_maximum_gpfn() + 1 gives either 0 or an invalid PFN due to
hardware limitation.
Futhermore, on ARM, xc_domain_maximum_gpfn() is not implemented and
return -ENOSYS. This will make libxc to use always the same PFN which
may colapse with an already mapped region (see xen/include/public/arch-arm.h
for the layout).
This patch only address the problem for ARM, the x86 version use the same
behavior (ie xc_domain_maximum_gpfn() + 1), as I'm not familiar with Xen x86.
A new function xc_core_arch_get_scratch_gpfn is introduced to be able to
choose the gpfn per architecture.
For the ARM version, we use the GUEST_GNTTAB_GUEST which is the base of
the region by the guest to map the grant table. At the build time,
nothing is mapped there.
At the same time correctly check the return of xc_domain_maximum_gpfn
for x86.
Signed-off-by: Julien Grall <julien.grall@linaro.org>
Cc: Jan Beulich <jbeulich@suse.com>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>
Cc: Roger Pau Monné <roger.pau@citrix.com>
Cc: Ian Jackson <ian.jackson@eu.citrix.com>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
(cherry picked from commit 5b5c40c0d1)
Using SELinux mount options per default breaks several systems.
Either the context= mount option is not known at all to the kernel,
as reported for ArchLinux. Or the default value "none" is unknown to
SELinux, as reported for Fedora. In both cases the unit will fail.
The proper place to specify mount options is /etc/fstab. Apparently
systemd is kind enough to use values from there even if Options= or
What= is specified in a .mount file.
Remove XENSTORED_MOUNT_CTX, the reference to a non-existent
EnvironmentFile and trim default Options= for the mount point.
The removed code was first mentioned in the patch referenced below,
with the following description:
...
* Some systems define the selinux context in the systemd Option for
the /var/lib/xenstored tmpfs:
Options=mode=755,context="system_u:object_r:xenstored_var_lib_t:s0"
For the upstream version we remove that and let systems specify
the context on their system /etc/default/xenstored or
/etc/sysconfig/xenstored $XENSTORED_MOUNT_CTX variable
...
It is nowhere stated (on xen-devel) what "Some systems" means, which
is unfortunately common practice in nearly all opensource projects.
http://lists.xenproject.org/archives/html/xen-devel/2014-03/msg02462.html
Signed-off-by: Olaf Hering <olaf@aepfle.de>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Cc: Wei Liu <wei.liu2@citrix.com>
Cc: Anthony PERARD <anthony.perard@citrix.com>
Cc: M A Young <m.a.young@durham.ac.uk>
Cc: Luis R. Rodriguez <mcgrof@do-not-panic.com>
Release-Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
- Use %lex-param instead of obsolete YYLEX_PARAM to override lex scanner
parameter
- Change deprecated %name-prefix= to %name-prefix
Tested against bison 2.4.1 and 3.0.2.
This is expected to sometimes (depending on timestamps and whether the
bison input files are edited) break building on systems with ancient
versions of bison. Bison 2.4.1 is known to work and was released in
December 2008.
Also, consquentially, regenerate bison output files with bison
1:2.5.dfsg-2.1 from Debian wheezy.
Signed-off-by: Ed Swierk <eswierk@skyportsystems.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Tested-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Release-Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Regenerate libxl_*_l.* with flex 2.5.35-10.1 as in current Debian
wheezy. The differences are trivial: addition of declarations of
xlu__cfg_yyget_column and xlu__cfg_yyset_column, but no code body
changes.
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Release-Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Ian Campbell
Anthony PERARD
Andrew Cooper
Jonathan Davies
Dario Faggioli
Ian Jackson
Julien Grall
Stefano Stabellini
Wei Liu
Konrad Rzeszutek Wilk
Ross Lagerwall
Eugene Korenevsky
Jan Beulich
Julien Grall
Jim Fehlig
Olaf Hering
Ed Swierk