Commit Graph
43559 Commits
Author SHA1 Message Date
Andrew Cooper e253d0a65c x86/vmx: Drop spec_ctrl load in VMEntry path
This is not needed now that the VMEntry path is not responsible for loading
the guest's MSR_SPEC_CTRL value.

Fixes: 81f0eaadf8 ("x86/spec-ctrl: Fix NMI race condition with VT-x MSR_SPEC_CTRL handling")
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
(cherry picked from commit 9ce3ef20b4)
2022-02-04 15:45:24 +00:00
Jan Beulich 0b7aba57b3 MAINTAINERS: Anthony is stable branch tools maintainer
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
2022-02-03 13:06:01 +01:00
Roger Pau Monné 8abb345e6b x86/pvh: fix population of the low 1MB for dom0
RMRRs are setup ahead of populating the p2m and hence the ASSERT when
populating the low 1MB needs to be relaxed when it finds an existing
entry: it's either RAM or a RMRR resulting from the IOMMU setup.

Rework the logic a bit and introduce a local mfn variable in order to
assert that if the gfn is populated and not RAM it is an identity map.

Fixes: 6b4f6a31ac ('x86/PVH: de-duplicate mappings for first Mb of Dom0 memory')
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
master commit: 2d5fc9120d
master date: 2022-01-25 10:52:24 +0000
2022-01-26 12:18:07 +01:00
Andrew Cooper fc87b55a34 x86: Fix build with the get/set_reg() infrastructure
I clearly messed up concluding that the stubs were safe to drop.

The is_{pv,hvm}_domain() predicates are not symmetrical with both CONFIG_PV
and CONFIG_HVM.  As a result logic of the form `if ( pv/hvm ) ... else ...`
will always have one side which can't be DCE'd.

While technically only the hvm stubs are needed, due to the use of the
is_pv_domain() predicate in guest_{rd,wr}msr(), sort out the pv stubs too to
avoid leaving a bear trap for future users.

Fixes: 88d3ff7ab1 ("x86/guest: Introduce {get,set}_reg() infrastructure")
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
master commit: 13caa58579
master date: 2022-01-21 12:42:11 +0000
2022-01-26 12:17:04 +01:00
Andrew Cooper d3cb547029 x86/spec-ctrl: Fix NMI race condition with VT-x MSR_SPEC_CTRL handling
The logic was based on a mistaken understanding of how NMI blocking on vmexit
works.  NMIs are only blocked for EXIT_REASON_NMI, and not for general exits.
Therefore, an NMI can in general hit early in the vmx_asm_vmexit_handler path,
and the guest's value will be clobbered before it is saved.

Switch to using MSR load/save lists.  This causes the guest value to be saved
atomically with respect to NMIs/MCEs/etc.

First, update vmx_cpuid_policy_changed() to configure the load/save lists at
the same time as configuring the intercepts.  This function is always used in
remote context, so extend the vmx_vmcs_{enter,exit}() block to cover the whole
function, rather than having multiple remote acquisitions of the same VMCS.

Both of vmx_{add,del}_guest_msr() can fail.  The -ESRCH delete case is fine,
but all others are fatal to the running of the VM, so handle them using
domain_crash() - this path is only used during domain construction anyway.

Second, update vmx_{get,set}_reg() to use the MSR load/save lists rather than
vcpu_msrs, and update the vcpu_msrs comment to describe the new state
location.

Finally, adjust the entry/exit asm.

Because the guest value is saved and loaded atomically, we do not need to
manually load the guest value, nor do we need to enable SCF_use_shadow.  This
lets us remove the use of DO_SPEC_CTRL_EXIT_TO_GUEST.  Additionally,
SPEC_CTRL_ENTRY_FROM_PV gets removed too, because on an early entry failure,
we're no longer in the guest MSR_SPEC_CTRL context needing to switch back to
Xen's context.

The only action remaining is to load Xen's MSR_SPEC_CTRL value on vmexit.  We
could in principle use the host msr list, but is expected to complicated
future work.  Delete DO_SPEC_CTRL_ENTRY_FROM_HVM entirely, and use a shorter
code sequence to simply reload Xen's setting from the top-of-stack block.

Adjust the comment at the top of spec_ctrl_asm.h in light of this bugfix.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
master commit: 81f0eaadf8
master date: 2022-01-20 16:32:11 +0000
2022-01-25 13:39:44 +01:00
Andrew Cooper 21d70feed1 x86/spec-ctrl: Drop SPEC_CTRL_{ENTRY_FROM,EXIT_TO}_HVM
These were written before Spectre/Meltdown went public, and there was large
uncertainty in how the protections would evolve.  As it turns out, they're
very specific to Intel hardware, and not very suitable for AMD.

Drop the macros, opencoding the relevant subset of functionality, and leaving
grep-fodder to locate the logic.  No change at all for VT-x.

For AMD, the only relevant piece of functionality is DO_OVERWRITE_RSB,
although we will soon be adding (different) logic to handle MSR_SPEC_CTRL.

This has a marginal improvement of removing an unconditional pile of long-nops
from the vmentry/exit path.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
master commit: 95b13fa43e
master date: 2022-01-20 16:32:11 +0000
2022-01-25 13:39:31 +01:00
Andrew Cooper cc6fe1bb13 x86/msr: Split MSR_SPEC_CTRL handling
In order to fix a VT-x bug, and support MSR_SPEC_CTRL on AMD, move
MSR_SPEC_CTRL handling into the new {pv,hvm}_{get,set}_reg() infrastructure.

Duplicate the msrs->spec_ctrl.raw accesses in the PV and VT-x paths for now.
The SVM path is currently unreachable because of the CPUID policy.

No functional change.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
master commit: 6536688439
master date: 2022-01-20 16:32:11 +0000
2022-01-25 13:39:16 +01:00
Andrew Cooper 20b00921f8 x86/guest: Introduce {get,set}_reg() infrastructure
Various registers have per-guest-type or per-vendor locations or access
requirements.  To support their use from common code, provide accessors which
allow for per-guest-type behaviour.

For now, just infrastructure handling default cases and expectations.
Subsequent patches will start handling registers using this infrastructure.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
master commit: 88d3ff7ab1
master date: 2022-01-20 16:32:11 +0000
2022-01-25 13:38:42 +01:00
Jason Andryuk 8509519268 libxl/PCI: Fix PV hotplug & stubdom coldplug
commit 0fdb48ffe7 "libxl: Make sure devices added by pci-attach are
reflected in the config" broken PCI hotplug (xl pci-attach) for PV
domains when it moved libxl__create_pci_backend() later in the function.

This also broke HVM + stubdom PCI passthrough coldplug.  For that, the
PCI devices are hotplugged to a running PV stubdom, and then the QEMU
QMP device_add commands are made to QEMU inside the stubdom.

A running PV domain calls libxl__wait_for_backend().  With the current
placement of libxl__create_pci_backend(), the path does not exist and
the call immediately fails:
libxl: error: libxl_device.c:1388:libxl__wait_for_backend: Backend /local/domain/0/backend/pci/43/0 does not exist
libxl: error: libxl_pci.c:1764:device_pci_add_done: Domain 42:libxl__device_pci_add failed for PCI device 0:2:0.0 (rc -3)
libxl: error: libxl_create.c:1857:domcreate_attach_devices: Domain 42:unable to add pci devices

The wait is only relevant when:
1) The domain is PV
2) The domain is running
3) The backend is already present

This is because:

1) xen-pcifront is only used for PV.  It does not load for HVM domains
   where QEMU is used.

2) If the domain is not running (starting), then the frontend state will
   be Initialising.  xen-pciback waits for the frontend to transition to
   at Initialised before attempting to connect.  So a wait for a
   non-running domain is not applicable as the backend will not
   transition to Connected.

3) For presence, num_devs is already used to determine if the backend
   needs to be created.  Re-use num_devs to determine if the backend
   wait is necessary.  The wait is necessary to avoid racing with
   another PCI attachment reconfiguring the front/back or changing to
   some other state like closing.  If we are creating the backend, then
   we don't have to worry about the state since it is being created.

Fixes: 0fdb48ffe7 ("libxl: Make sure devices added by pci-attach are
reflected in the config")

Signed-off-by: Jason Andryuk <jandryuk@gmail.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
master commit: 73ee2795aa
master date: 2022-01-13 14:33:16 +0100
2022-01-25 13:38:14 +01:00
Jan Beulich fd343ec092 x86/time: improve TSC / CPU freq calibration accuracy
While the problem report was for extreme errors, even smaller ones would
better be avoided: The calculated period to run calibration loops over
can (and usually will) be shorter than the actual time elapsed between
first and last platform timer and TSC reads. Adjust values returned from
the init functions accordingly.

On a Skylake system I've tested this on accuracy (using HPET) went from
detecting in some cases more than 220kHz too high a value to about
±2kHz. On other systems (or on this system, but with PMTMR) the original
error range was much smaller, with less (in some cases only very little)
improvement.

Reported-by: James Dingwall <james-xen@dingwall.me.uk>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
master commit: a5c9a80af3
master date: 2022-01-13 14:31:52 +0100
2022-01-25 13:37:59 +01:00
Jan Beulich 4774d06097 x86/time: use relative counts in calibration loops
Looping until reaching/exceeding a certain value is error prone: If the
target value is close enough to the wrapping point, the loop may not
terminate at all. Switch to using delta values, which then allows to
fold the two loops each into just one.

Fixes: 9334029780 ("x86/time: calibrate TSC against platform timer")
Reported-by: Roger Pau Monné <roger.pau@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
master commit: 467191641d
master date: 2022-01-13 14:30:18 +0100
2022-01-25 13:37:45 +01:00
Julien Grall 18d0f50159 passthrough/x86: stop pirq iteration immediately in case of error
pt_pirq_iterate() will iterate in batch over all the PIRQs. The outer
loop will bail out if 'rc' is non-zero but the inner loop will continue.

This means 'rc' will get clobbered and we may miss any errors (such as
-ERESTART in the case of the callback pci_clean_dpci_irq()).

This is CVE-2022-23035 / XSA-395.

Fixes: c24536b636 ("replace d->nr_pirqs sized arrays with radix tree")
Fixes: f6dd295381 ("dpci: replace tasklet with softirq")
Signed-off-by: Julien Grall <jgrall@amazon.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
master commit: 9480a1a519
master date: 2022-01-25 13:27:02 +0100
2022-01-25 13:35:23 +01:00
Julien Grall 965fbc8e80 xen/grant-table: Only decrement the refcounter when grant is fully unmapped
The grant unmapping hypercall (GNTTABOP_unmap_grant_ref) is not a
simple revert of the changes done by the grant mapping hypercall
(GNTTABOP_map_grant_ref).

Instead, it is possible to partially (or even not) clear some flags.
This will leave the grant is mapped until a future call where all
the flags would be cleared.

XSA-380 introduced a refcounting that is meant to only be dropped
when the grant is fully unmapped. Unfortunately, unmap_common() will
decrement the refcount for every successful call.

A consequence is a domain would be able to underflow the refcount
and trigger a BUG().

Looking at the code, it is not clear to me why a domain would
want to partially clear some flags in the grant-table. But as
this is part of the ABI, it is better to not change the behavior
for now.

Fix it by checking if the maptrack handle has been released before
decrementing the refcounting.

This is CVE-2022-23034 / XSA-394.

Fixes: 9781b51efd ("gnttab: replace mapkind()")
Signed-off-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
master commit: 975a8fb45c
master date: 2022-01-25 13:25:49 +0100
2022-01-25 13:35:08 +01:00
Julien Grall acdb674446 xen/arm: p2m: Always clear the P2M entry when the mapping is removed
Commit 2148a125b7 ("xen/arm: Track page accessed between batch of
Set/Way operations") allowed an entry to be invalid from the CPU PoV
(lpae_is_valid()) but valid for Xen (p2m_is_valid()). This is useful
to track which page is accessed and only perform an action on them
(e.g. clean & invalidate the cache after a set/way instruction).

Unfortunately, __p2m_set_entry() is only zeroing the P2M entry when
lpae_is_valid() returns true. This means the entry will not be zeroed
if the entry was valid from Xen PoV but invalid from the CPU PoV for
tracking purpose.

As a consequence, this will allow a domain to continue to access the
page after it was removed.

Resolve the issue by always zeroing the entry if it the LPAE bit is
set or the entry is about to be removed.

This is CVE-2022-23033 / XSA-393.

Reported-by: Dmytro Firsov <Dmytro_Firsov@epam.com>
Fixes: 2148a125b7 ("xen/arm: Track page accessed between batch of Set/Way operations")
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Signed-off-by: Julien Grall <jgrall@amazon.com>
master commit: a428b913a0
master date: 2022-01-25 13:25:01 +0100
2022-01-25 13:34:55 +01:00
Andrew Cooper 243026a2c5 x86/spec-ctrl: Fix default calculation of opt_srb_lock
Since this logic was introduced, opt_tsx has become more complicated and
shouldn't be compared to 0 directly.  While there are no buggy logic paths,
the correct expression is !(opt_tsx & 1) but the rtm_disabled boolean is
easier and clearer to use.

Fixes: 8fe24090d9 ("x86/cpuid: Rework HLE and RTM handling")
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
master commit: 31f3bc97f4
master date: 2022-01-05 09:44:26 +0000
2022-01-06 14:15:14 +01:00
Andrew Cooper 1172a4359e x86/cpuid: Fix TSXLDTRK definition
TSXLDTRK lives in CPUID leaf 7[0].edx, not 7[0].ecx.

Bit 16 in ecx is LA57.

Fixes: a6d1b55847 ("x86emul: support X{SUS,RES}LDTRK")
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
master commit: 249e0f1d8f
master date: 2021-12-14 12:30:48 +0000
2022-01-06 14:14:39 +01:00
Jan Beulich 1bba0ce1d9 revert "hvmloader: PA range 0xfc000000-0xffffffff should be UC"
This reverts commit c22bd567ce.

While its description is correct from an abstract or real hardware pov,
the range is special inside HVM guests. The range being UC in particular
gets in the way of OVMF, which places itself at [FFE00000,FFFFFFFF].
While this is benign to epte_get_entry_emt() as long as the IOMMU isn't
enabled for a guest, it becomes a very noticable problem otherwise: It
takes about half a minute for OVMF to decompress itself into its
designated address range.

And even beyond OVMF there's no reason to have e.g. the ACPI memory
range marked UC.

Fixes: c22bd567ce ("hvmloader: PA range 0xfc000000-0xffffffff should be UC")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: ea187c0b7a
master date: 2021-12-17 08:56:15 +0100
2022-01-06 14:14:19 +01:00
Jan Beulich 98ea29cd71 x86/HVM: permit CLFLUSH{,OPT} on execute-only code segments
Both SDM and PM explicitly permit this.

Fixes: 52dba7bd0b ("x86emul: generalize wbinvd() hook")
Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Paul Durrant <paul@xen.org>
master commit: df3e1a5efe
master date: 2021-12-10 14:03:56 +0100
2022-01-06 14:13:38 +01:00
Jan Beulich 64a35ee749 x86: avoid wrong use of all-but-self IPI shorthand
With "nosmp" I did observe a flood of "APIC error on CPU0: 04(04), Send
accept error" log messages on an AMD system. And rightly so - nothing
excludes the use of the shorthand in send_IPI_mask() in this case. Set
"unaccounted_cpus" to "true" also when command line restrictions are the
cause.

Note that PV-shim mode is unaffected by this change, first and foremost
because "nosmp" and "maxcpus=" are ignored in this case.

Fixes: 5500d265a2 ("x86/smp: use APIC ALLBUT destination shorthand when possible")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 7621880de0
master date: 2021-12-10 10:26:52 +0100
2022-01-06 14:12:53 +01:00
Jan Beulich 7bbeff438d x86/HVM: fail virt-to-linear conversion for insn fetches from non-code segments
Just like (in protected mode) reads may not go to exec-only segments and
writes may not go to non-writable ones, insn fetches may not access data
segments.

Fixes: 623e837167 ("hvm: Support hardware task switching")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 311297f421
master date: 2021-12-06 14:15:05 +0100
2022-01-06 14:12:26 +01:00
Jan Beulich 481b8bb331 x86/Viridian: fix error code use
Both the wrong use of HV_STATUS_* and the return type of
hv_vpset_to_vpmask() can lead to viridian_hypercall()'s
ASSERT_UNREACHABLE() triggering when translating error codes from Xen
to Viridian representation.

Fixes: b4124682db ("viridian: add ExProcessorMasks variants of the flush hypercalls")
Fixes: 9afa867d42 ("viridian: add ExProcessorMasks variant of the IPI hypercall")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Paul Durrant <paul@xen.org>
master commit: 857fee7784
master date: 2021-11-24 11:09:56 +0100
2022-01-06 14:11:58 +01:00
Jan Beulich 84977e8b53 VT-d: don't leak domid mapping on error path
While domain_context_mapping() invokes domain_context_unmap() in a sub-
case of handling DEV_TYPE_PCI when encountering an error, thus avoiding
a leak, individual calls to domain_context_mapping_one() aren't
similarly covered. Such a leak might persist until domain destruction.
Leverage that these cases can be recognized by pdev being non-NULL.

Fixes: dec403cc66 ("VT-d: fix iommu_domid for PCI/PCIx devices assignment")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
master commit: e6252a51fa
master date: 2021-11-24 11:07:11 +0100
2022-01-06 14:11:23 +01:00
Jan Beulich fa45f6b556 VT-d: split domid map cleanup check into a function
This logic will want invoking from elsewhere.

No functional change intended.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
master commit: 9fdc10abe9
master date: 2021-11-24 11:06:20 +0100
2022-01-06 14:10:05 +01:00
Luca Fancellu d0d0af67ee docs/efi: Fix wrong compatible in dts example
The example in section "UEFI boot and dom0less on ARM" has a wrong
compatible for the DTB passthrough, it is "ramdisk" instead of
"device-tree".

This patch fixes the example.

Fixes: a1743fc3a9 ("arm/efi: Use dom0less configuration when using EFI boot")
Signed-off-by: Luca Fancellu <luca.fancellu@arm.com>
Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com>
Acked-by: Julien Grall <jgrall@amazon.com>
(cherry picked from commit 620ed2c8c7)
2021-12-13 13:54:50 -08:00
Ian Jackson 2dcea9c94c REAMDE: trim over-long lines around figlet
Signed-off-by: Ian Jackson <iwj@xenproject.org>
2021-12-06 15:46:27 +00:00
Ian Jackson 5974b00dd6 MAINTAINERS: Update for this being the 4.16 stable branch
Signed-off-by: Ian Jackson <iwj@xenproject.org>
2021-12-06 15:46:27 +00:00
Ian Jackson d9faedccd9 xen/Makefile: Set version to reopen as 4.16 stable branch
Signed-off-by: Ian Jackson <iwj@xenproject.org>
2021-12-06 15:46:27 +00:00
Ian Jackson b0b4661fa3 xen/Makefile: Set 4.16 version
Signed-off-by: Ian Jackson <iwj@xenproject.org>
RELEASE-4.16.0
2021-11-30 11:42:42 +00:00
Ian Jackson 36aa64095d CHANGELOG.md: Set 4.16 version and date
Signed-off-by: Ian Jackson <iwj@xenproject.org>
2021-11-30 11:42:00 +00:00
Ian Jackson 47378e2663 README: make heading say 4.16
Signed-off-by: Ian Jackson <iwj@xenproject.org>
2021-11-30 11:42:00 +00:00
Ian Jackson 01912f6c5f SUPPORT.md: Define support lifetime
Signed-off-by: Ian Jackson <iwj@xenproject.org>
Acked-by: Jan Beulich <jbeulich@suse.com>
2021-11-30 11:42:00 +00:00
Ian Jackson c9b5e2fb62 Config.mk: Bump tags to 4.16.0 final
No actual change to the code since RC4.

Signed-off-by: Ian Jackson <iwj@xenproject.org>
2021-11-30 11:42:00 +00:00
Roger Pau Monne e2544a28be CHANGELOG: add missing entries for work during the 4.16 release cycle
Document some of the relevant changes during the 4.16 release cycle.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Release-Acked-by: Ian Jackson <iwj@xenproject.org>
2021-11-30 11:42:00 +00:00
Andrew Cooper c4b41ee2b4 Revert "x86/CPUID: shrink max_{,sub}leaf fields according to actual leaf contents"
OSSTest has identified a 3rd regression caused by this change.  Migration
between Xen 4.15 and 4.16 on the nocera pair of machines (AMD Opteron 4133)
fails with:

  xc: error: Failed to set CPUID policy: leaf 00000000, subleaf ffffffff, msr ffffffff (22 = Invalid argument): Internal error
  xc: error: Restore failed (22 = Invalid argument): Internal error

which is a safety check to prevent resuming the guest when the CPUID data has
been truncated.  The problem is caused by shrinking of the max policies, which
is an ABI that needs handling compatibly between different versions of Xen.

Furthermore, shrinking of the default policies also breaks things in some
cases, because certain cpuid= settings in a VM config file which used to have
an effect will now be silently discarded.

This reverts commit 540d911c28, as well as the
partial fix attempt in 81da2b544c (which added
one new case where cpuid= settings might not apply correctly) and restores the
same behaviour as Xen 4.15.

Fixes: 540d911c28 ("x86/CPUID: shrink max_{,sub}leaf fields according to actual leaf contents")
Fixes: 81da2b544c ("x86/cpuid: prevent shrinking migrated policies max leaves")
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Release_Acked-by: Ian Jackson <iwj@xenproject.org>
2021-11-25 11:06:12 +00:00
Ian Jackson 59505f48fa Turn off debug by default
Signed-off-by: Ian Jackson <iwj@xenproject.org>
2021-11-23 16:43:49 +00:00
Ian Jackson 4d9eed0612 SUPPORT.md: Set Release Notes link
Signed-off-by: Ian Jackson <iwj@xenproject.org>
2021-11-23 16:43:49 +00:00
Ian Jackson c6fbb058f6 Config.mk: switch to named tags (for stable branch)
Signed-off-by: Ian Jackson <iwj@xenproject.org>
2021-11-23 16:43:49 +00:00
Jan Beulich 74a11c43fd x86/P2M: deal with partial success of p2m_set_entry()
M2P and PoD stats need to remain in sync with P2M; if an update succeeds
only partially, respective adjustments need to be made. If updates get
made before the call, they may also need undoing upon complete failure
(i.e. including the single-page case).

Log-dirty state would better also be kept in sync.

Note that the change to set_typed_p2m_entry() may not be strictly
necessary (due to the order restriction enforced near the top of the
function), but is being kept here to be on the safe side.

This is CVE-2021-28705 and CVE-2021-28709 / XSA-389.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
4.16.0-rc4
2021-11-22 12:27:30 +00:00
Jan Beulich 8ec13f68e0 x86/PoD: handle intermediate page orders in p2m_pod_cache_add()
p2m_pod_decrease_reservation() may pass pages to the function which
aren't 4k, 2M, or 1G. Handle all intermediate orders as well, to avoid
hitting the BUG() at the switch() statement's "default" case.

This is CVE-2021-28708 / part of XSA-388.

Fixes: 3c352011c0 ("x86/PoD: shorten certain operations on higher order ranges")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
2021-11-22 12:27:30 +00:00
Jan Beulich 182c737b9b x86/PoD: deal with misaligned GFNs
Users of XENMEM_decrease_reservation and XENMEM_populate_physmap aren't
required to pass in order-aligned GFN values. (While I consider this
bogus, I don't think we can fix this there, as that might break existing
code, e.g Linux'es swiotlb, which - while affecting PV only - until
recently had been enforcing only page alignment on the original
allocation.) Only non-PoD code paths (guest_physmap_{add,remove}_page(),
p2m_set_entry()) look to be dealing with this properly (in part by being
implemented inefficiently, handling every 4k page separately).

Introduce wrappers taking care of splitting the incoming request into
aligned chunks, without putting much effort in trying to determine the
largest possible chunk at every iteration.

Also "handle" p2m_set_entry() failure for non-order-0 requests by
crashing the domain in one more place. Alongside putting a log message
there, also add one to the other similar path.

Note regarding locking: This is left in the actual worker functions on
the assumption that callers aren't guaranteed atomicity wrt acting on
multiple pages at a time. For mis-aligned GFNs gfn_lock() wouldn't have
locked the correct GFN range anyway, if it didn't simply resolve to
p2m_lock(), and for well-behaved callers there continues to be only a
single iteration, i.e. behavior is unchanged for them. (FTAOD pulling
out just pod_lock() into p2m_pod_decrease_reservation() would result in
a lock order violation.)

This is CVE-2021-28704 and CVE-2021-28707 / part of XSA-388.

Fixes: 3c352011c0 ("x86/PoD: shorten certain operations on higher order ranges")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
2021-11-22 12:27:30 +00:00
Julien Grall 143501861d xen/page_alloc: Harden assign_pages()
domain_tot_pages() and d->max_pages are 32-bit values. While the order
should always be quite small, it would still be possible to overflow
if domain_tot_pages() is near to (2^32 - 1).

As this code may be called by a guest via XENMEM_increase_reservation
and XENMEM_populate_physmap, we want to make sure the guest is not going
to be able to allocate more than it is allowed.

Rework the allocation check to avoid any possible overflow. While the
check domain_tot_pages() < d->max_pages should technically not be
necessary, it is probably best to have it to catch any possible
inconsistencies in the future.

This is CVE-2021-28706 / part of XSA-385.

Signed-off-by: Julien Grall <jgrall@amazon.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
2021-11-22 11:11:05 +00:00
Roger Pau Monne be12fcca8b efi: fix alignment of function parameters in compat mode
Currently the max_store_size, remain_store_size and max_size in
compat_pf_efi_runtime_call are 4 byte aligned, which makes clang
13.0.0 complain with:

In file included from compat.c:30:
./runtime.c:646:13: error: passing 4-byte aligned argument to 8-byte aligned parameter 2 of 'QueryVariableInfo' may result in an unaligned pointer access [-Werror,-Walign-mismatch]
            &op->u.query_variable_info.max_store_size,
            ^
./runtime.c:647:13: error: passing 4-byte aligned argument to 8-byte aligned parameter 3 of 'QueryVariableInfo' may result in an unaligned pointer access [-Werror,-Walign-mismatch]
            &op->u.query_variable_info.remain_store_size,
            ^
./runtime.c:648:13: error: passing 4-byte aligned argument to 8-byte aligned parameter 4 of 'QueryVariableInfo' may result in an unaligned pointer access [-Werror,-Walign-mismatch]
            &op->u.query_variable_info.max_size);
            ^
Fix this by bouncing the variables on the stack in order for them to
be 8 byte aligned.

Note this could be done in a more selective manner to only apply to
compat code calls, but given the overhead of making an EFI call doing
an extra copy of 3 variables doesn't seem to warrant the special
casing.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Release-Acked-by: Ian Jackson <iwj@xenproject.org>
Reviewed-by: Ian Jackson <iwj@xenproject.org>
Signed-off-by: Ian Jackson <iwj@xenproject.org>
Reviewed-by: Jan Beulich <jbeulich@suse.com>

---
Changes since v3:
 - Remove hard tabs.  Apply Jan's r-b as authorised in email.
Changes since v2:
 - Adjust the commentary as per discussion.
Changes since v1:
 - Copy back the results.
2021-11-19 17:01:24 +00:00
Anthony PERARD 24d7cc416b golang/xenlight: regen generated code
Fixes: 7379f9e10a ("gnttab: allow setting max version per-domain")
Fixes: 1e6706b0d1 ("xen/arm: Introduce gpaddr_bits field to struct xen_domctl_getdomaininfo")
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Nick Rosbrook <rosbrookn@ainfosec.com>
Acked-by: Ian Jackson <iwj@xenproject.org>
Release-Acked-by: Ian Jackson <iwj@xenproject.org>
2021-11-19 14:33:55 +00:00
Jan Beulich 02b46377b6 VT-d: fix reduced page table levels support when sharing tables
domain_pgd_maddr() contains logic to adjust the root address to be put
in the context entry in case 4-level page tables aren't supported by an
IOMMU. This logic may not be bypassed when sharing page tables.

This is CVE-2021-28710 / XSA-390.

Fixes: 25ccd09342 ("iommu: remove the share_p2m operation")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Release-Acked-by: Ian Jackson <iwj@xenproject.org>
2021-11-19 15:14:08 +01:00
Roger Pau Monné 1cffc48f1e tools/python: fix python libxc bindings to pass a max grant version
Such max version should be provided by the caller, otherwise the
bindings will default to specifying a max version of 2, which is
inline with the current defaults in the hypervisor.

Fixes: 7379f9e10a ('gnttab: allow setting max version per-domain')
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Ian Jackson <iwj@xenproject.org>
Acked-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Release-Acked-by: Ian Jackson <iwj@xenproject.org>
2021-11-17 12:43:05 +01:00
Roger Pau Monné 27ece0dd52 CHANGELOG: set Xen 4.15 release date
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Release-Acked-by: Ian Jackson <iwj@xenproject.org>
2021-11-17 12:35:26 +01:00
Roger Pau Monné 306e0afbb3 test/tsx: set grant version for created domains
Set the grant table version for the created domains to use version 1,
as such tests domains don't require the usage of the grant table at
all. A TODO note is added to switch those dummy domains to not have a
grant table at all when possible. Without setting the grant version
the domains for the tests cannot be created.

Fixes: 7379f9e10a ('gnttab: allow setting max version per-domain')
Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reported-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Release-Acked-by: Ian Jackson <iwj@xenproject.org>
2021-11-17 08:13:18 +01:00
Roger Pau Monné 810fbc03ff tests/resource: set grant version for created domains
Set the grant table version for the created domains to use version 1,
as that's the used by the test cases. Without setting the grant
version the domains for the tests cannot be created.

Fixes: 7379f9e10a ('gnttab: allow setting max version per-domain')
Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Release-Acked-by: Ian Jackson <iwj@xenproject.org>
2021-11-17 08:13:02 +01:00
Roger Pau Monné 2abeaf319c domctl: introduce a macro to set the grant table max version
Such macro just clamps the passed version to fit in the designated
bits of the domctl field. The main purpose is to make it clearer in
the code when max grant version is being set in the grant_opts field.

Existing users that where setting the version in the grant_opts field
are switched to use the macro.

No functional change intended.

Requested-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com>
Acked-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Ian Jackson <iwj@xenproject.org>
Release-Acked-by: Ian Jackson <iwj@xenproject.org>
2021-11-17 08:12:00 +01:00
Jan Beulich 2d72d2784e public/gnttab: relax v2 recommendation
With there being a way to disable v2 support, telling new guests to use
v2 exclusively is not a good suggestion.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Luca Fancellu <luca.fancellu@arm.com>
Release-Acked-by: Ian Jackson <iwj@xenproject.org>
4.16.0-rc3
2021-11-16 17:34:06 +01:00