Commit Graph
16437 Commits
Author SHA1 Message Date
Andrii Sultanov dbf9a090ba tools/ocaml: implement stub_xc_domain_create() for ARM
stub_xc_domain_create() fails unconditionally with "Unhandled: ARM" for
the ARM variant of arch_domainconfig, so no OCaml toolstack (e.g.
xenopsd) can create an ARM domain.

To fix this, convert the two fields of xen_arm_arch_domainconfig,
gic_version and nr_spis, into the corresponding fields of struct
xen_arch_domainconfig and reject values that do not fit, as is already
done for other parameters. The remaining fields (sve_vl, tee_type,
arm_sci_type and v8r_el1_msa) aren't exposed to OCaml yet, so they stay
zero.

Also add a BUILD_BUG_ON() on the size of the createdomain struct, just
like the x86 case, to catch future ABI changes.

Signed-off-by: Andrii Sultanov <andriy.sultanov@vates.tech>
Signed-off-by: Julian Vetter <julian.vetter@vates.tech>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2026-10-22 13:40:20 +01:00
Julian Vetter baaa185201 xen/arm: report clock_frequency via sysctl physinfo, not createdomain
The xen_arch_domainconfig.clock_frequency value is populated in
domain_vtimer_init() during XEN_DOMCTL_createdomain from the global
timer_dt_clock_frequency, which comes from the host's DT timer node and
has nothing to do with the domain being created. Like now removed
GIC_NATIVE resolution, this is a host-wide system property being
smuggled out through a domain-creation IN struct.

Expose it instead as a new arm_clock_frequency_hz field in
XEN_SYSCTL_physinfo, populated via arch_do_physinfo(), and mirroring how
the GIC capability bits were already moved there.

Rather than making the field dependant on DT boot, make Xen always
report the timer frequency, either via the DT "clock-frequency" node, or
directly via CNTFRQ_EL0. preinit_xen_time() already computes cpu_khz for
every boot path. The renamed timer_clock_frequency_hz now captures
whichever of the two produced that value, in full Hz precision, instead
of only recording the DT case. So, ACPI guests get a real value too,
allowing to drop the special case.

The DT "clock-frequency" property exists because firmware might leave
CNTFRQ_EL0 wrong, and since CNTFRQ_EL0 cannot be trapped the only fix is
to replicate the correct value into the guest DT. To keep that signal, a
new XEN_SYSCTL_PHYSCAP_ARM_TIMER_DT_FREQ capability bit records whether
arm_clock_frequency_hz came from the DT property. Then libxl only emits
a "clock-frequency" property into the guest timer node when that bit is
set. A guest whose CNTFRQ_EL0 is already correct keeps an unmodified
timer node, exactly as before.

Although the CNTFRQ_EL0 register is 64 bits wide, and some current timer
implementations run at 1GHz, a 32bit value is sufficient to store the
timer value, because it only mirrors the DT 'clock-frequency' property,
which the bindings define as a single 32-bit cell.

In struct xen_sysctl_physinfo the new field just reuses the former pad
word, so sysctl consumers are unaffected. struct xen_arch_domainconfig
however loses clock_frequency from its middle, which shrinks the struct
and shifts every field after it, so bump XEN_DOMCTL_INTERFACE_VERSION.

The xen_arch_domainconfig parameter passed to domain_vtimer_init() is no
longer needed, so drop that parameter entirely. libxl now fetches the
frequency via libxl_get_physinfo() in libxl__arch_domain_save_config()
instead of reading it back out of the createdomain reply. The OCaml
xen_arch_domainconfig mirror drops the field too.

Signed-off-by: Julian Vetter <julian.vetter@vates.tech>
Reviewed-by: Michal Orzel <michal.orzel@amd.com>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
2026-10-14 16:32:32 +02:00
Julian Vetter 93e976a1d1 tools/arm: choose GIC version explicitly instead of relying on GIC_NATIVE
XEN_DOMCTL_CONFIG_GIC_NATIVE lets the toolstack ask Xen to silently
resolve the domain's GIC version to whatever the host hardware has. Xen
then writes the resolved value back into the same in/out
xen_arch_domainconfig the toolstack used as input, which is the kind of
API abuse we're trying to get rid of. The struct passed to createdomain
should only be an input parameter.

Move the "pick the best available GIC version" decision to the
toolstack, using the XEN_SYSCTL_PHYSCAP_ARM_GIC_V2/V3 capability bits
already exposed via XEN_SYSCTL_physinfo:

 * libxl__arch_domain_build_info_setdefault() resolves the GIC version
   against those bits before the config is built. An unspecified version
   becomes v3 if available, else v2, else fails. An explicitly requested
   v2/v3 is validated against the same bits, so a version the host
   cannot provide is directly rejected in the toolstack.
 * The Python xc.domain_create() binding does the same via a call to
   xc_physinfo().
 * libxl__arch_domain_prepare_config() therefore only ever sees a
   concrete v2/v3 request and just validates it. The GIC_NATIVE case is
   dropped since setdefault() always resolves it first.

LIBXL_GIC_VERSION_DEFAULT keeps its name and value: xl.cfg still accepts
"default" as the C<gic_version> keyword, and setdefault() resolves it to
a concrete v2/v3 before anything else can observe it.

This guarantees no toolstack path can still produce
XEN_DOMCTL_CONFIG_GIC_NATIVE, in preparation for removing it from the
Xen side and from the ABI entirely.

Signed-off-by: Julian Vetter <julian.vetter@vates.tech>
Acked-by: Michal Orzel <michal.orzel@amd.com>
Acked-by: Anthony PERARD <anthony.perard@vates.tech>
2026-10-14 16:32:32 +02:00
Juergen Gross 6b30eca0e3 tools/xenstored: fix live update with watches specifying depth
Due to a typo the state record for a watch specifying a depth is
written only partially. Instead of using the correct length of the
xs_state_watch_ext structure only the length of the xs_state_watch
structure was used when writing the data.

Fix that by using the correct length.

This is XSA-514 / CVE-2026-79607

Fixes: db98de120c ("tools/xenstored: add depth information to watches")
Reported-by: Andrii Sultanov <andriy.sultanov@vates.tech>
Signed-off-by: Juergen Gross <jgross@suse.com>
2026-10-13 13:47:27 +01:00
Andrew Mbugua 1771ba8450 tools/console/daemon: fix log_dir memory leak in xenconsoled
Valgrind reports that 21 bytes are "still reachable" from the (XEN_LOG_DIR "/console") allocation:

HEAP SUMMARY:
    in use at exit: 21 bytes in 1 blocks
    total heap usage: 9 allocs, 8 frees, 4,799 bytes allocated

Since the dynamic memory allocation for the default log directory path happens before the process
forks into the background, the parent and intermediate processes exit during daemonize()
with the memory still reachable.

Move the strdup() allocation down below the daemonize() block. This ensures only the final
background daemon allocates the default path, matching the lifetime of the free(log_dir)
cleanup loop at the exit of main().

With this change, Valgrind reports a clean heap summary

HEAP SUMMARY:
    in use at exit: 0 bytes in 0 blocks
    total heap usage: 8 allocs, 8 frees, 4,778 bytes allocated

Signed-off-by: Andrew Mbugua <andrewprecious388@gmail.com>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
2026-10-12 17:31:39 +02:00
Matthias Goergens 292fb23a92 tools/xentop: reject invalid --delay and --iterations arguments
xentop parses -d/--delay and -i/--iterations with atoi(), so invalid
input is silently accepted with surprising results: a fractional delay
such as "-d 2.5" is truncated to 2; "-d abc" parses as 0, which in
batch mode turns the output loop into a busy loop; "-d -1" wraps to an
effective delay of about 136 years; and "-i 0" (or any unparsable
iterations count) decrements an unsigned counter from zero, running
for about 2^32 iterations.  atoi() also has undefined behaviour on
out-of-range input.

Parse both options with strtoull() instead, and reject anything that
is not a plain decimal integer in range: a sign, a fractional part,
trailing junk or overflow now produce an error and exit rather than a
silently wrong value.

Compatibility considerations: "--delay 0" remains accepted, since
updating as fast as possible is a plausible deliberate choice and
works today; "--iterations 0" is rejected, since running the loop
2^32 times cannot be what the caller meant.  The interactive 'D'
prompt already validates its input and is unchanged.  The only
previously useful invocation this breaks is a fractional delay, which
now fails loudly instead of silently rounding down - which is the
point of the change.

A patch documenting the --delay truncation was posted in 2010 but
never applied:
Link: https://lore.kernel.org/xen-devel/01ea26d2420e3562eb30.1292604768@chilopoda.uk.xensource.com/

Signed-off-by: Matthias Goergens <matthias.goergens@gmail.com>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
2026-10-12 17:31:39 +02:00
Olivier Lambert 0c53660c1c tools/libxenstat: don't lose all VIFs when dom0 has no Linux bridge
xenstat_collect_networks() looks for a Linux bridge (a
/sys/class/net/*/bridge directory) so that, with bonding, dom0 can be
given the bridge's counters. When there is none, as on hosts using Open
vSwitch (the XCP-ng default), routed networking or only libvirt's
virbr0 (which is excluded on purpose), getBridge() leaves devBridge
empty. strstr(iface, "") then matches every interface, and devNoBridge
is just "p", so every VIF with a standard name (vifN.M, vifN.M-emu)
takes the bridge branch instead of being attached to its domain. Every
domain ends up with zero networks, and xentop shows NETS 0.

Only take the bridge branch when a bridge was actually found.

Fixes: 1fd93d4f8c ("xenstat: Linux dom0 statistics for case we use network bonding")
Assisted-by: Claude-Code:claude-opus-5-5
Signed-off-by: Olivier Lambert <olivier.lambert@vates.tech>
Tested-by: Jason Andryuk <jason.andryuk@amd.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
Acked-by: Anthony PERARD <anthony.perard@vates.tech>
2026-10-12 17:31:39 +02:00
Leigh Brown a1eb020cab tools/hotplug/Linux: Add bridge VLAN support
Update add_to_bridge shell function to read the vlan parameter from
xenstore and set the bridge VLAN configuration for the VID.

Add additional helper functions to parse the vlan specification,
which consists of one or more of the following:

a) single VLAN (e.g. 10).
b) contiguous range of VLANs (e.g. 10-15).
c) discontiguous range with base, increment and count
   (e.g. 100+10x9 which gives VLAN IDs 100, 110, ... 190).

A single VLAN can be suffixed with "p" to indicate the PVID, or
"u" to indicate untagged. A range of VLANs can be suffixed with
"u" to indicate untagged.  A complex example would be:

   vlan=1p/10-15/20-25u

This capability requires the iproute2 bridge command to be
installed.  An error will be generated if the vlan parameter is
set and the bridge command is not available.

Signed-off-by: Leigh Brown <leigh@solinno.co.uk>
Acked-by: Anthony PERARD <anthony.perard@vates.tech>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
2026-10-12 17:31:39 +02:00
James Dingwall 7d6c3308cb tools/hotplug: validate mtu read from xenstore against RFC 791 minimum
RFC 791 sets the minimum acceptable mtu to 68:

    Every internet module must be able to forward a datagram of 68
    octets without further fragmentation.  This is because an internet
    header may be up to 60 octets, and the minimum fragment is 8 octets.

In the Linux kernel source:

include/net/ip.h:#define IPV4_MIN_MTU           68              /* RFC 791 */

While there is no reason to expect a value <68 to be read from xenstore or
from the bridge make the value test require a number >= this minimum.

Signed-off-by: James Dingwall <james@dingwall.me.uk>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
2026-10-12 17:31:39 +02:00
James Dingwall 26b1671a1c tools/hotplug: fix invalid frontend path for set_mtu
The set_mtu() function of xen-network-common.sh currently has this code:

        if [ ${type_if} = vif ]
        then
            local dev_=${dev#vif}
            local domid=${dev_%.*}
            local devid=${dev_#*.}

            local FRONTEND_PATH="/local/domain/$domid/device/vif/$devid"

            xenstore_write "$FRONTEND_PATH/mtu" ${mtu}
        fi

This works fine if the device has its default name but if the xen config
defines the vifname parameter the FRONTEND_PATH is incorrectly constructed.
Learn the frontend path by reading the appropriate value from the backend.

Also change use of `...` to $(...) for a consistent style in the script.

Signed-off-by: James Dingwall <james@dingwall.me.uk>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
2026-10-12 17:31:39 +02:00
Ross Lagerwall 0aa64f1929 tools/libxl: Add support for Viridian stimer direct mode
Add support to libxl for using the stimer enlightenments in direct mode.

Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Acked-by: Anthony PERARD <anthony.perard@vates.tech>
2026-10-12 17:31:39 +02:00
Furkan Caliskan 31405d5bee tools: expose admission control toggle via xl sched-rtds
Wire the per-cpupool admission-control switch through libxl
to xl sched-rtds, and document it.

Add -s/--schedparam to list or set pool-wide RTDS scheduler
parameters, and -a/--admission to enable or disable admission
control for a cpupool ("-c pool -s -a 0/1").

Signed-off-by: Furkan Caliskan <frn1furkan10@gmail.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Acked-by: Anthony PERARD <anthony.perard@vates.tech>
2026-10-12 17:20:27 +02:00
Weiqi Wang c161c11875 xen/pdx: fix offset-compression merge of a contained range
When sorting and merging overlapping ranges in
pfn_pdx_compression_setup(), the merged range is set to end where the
second range ends.  If the second range is fully contained in the first,
this truncates the first range, and the tail of it is then neither
compressible nor translated correctly.

Keep the end of the merged range as the maximum of both ends.

On x86 the ranges come from the SRAT memory affinity entries, and
overlapping entries for the same node are tolerated with a warning by the
NUMA code.  The caller's subsequent coverage check catches the truncated
range, so the effect is that PDX compression is disabled with a "RAM
region ... not covered" message rather than memory being mistranslated.

Add a test case that fails without this change.

Found with the ESBMC bounded model checker, and confirmed by running the
failing case natively against the unmodified code.

Fixes: c5c45bcbd6 ("pdx: introduce a new compression algorithm based on region offsets")
Assisted-by: Claude Code:claude-opus-5-5 # finding the issue with ESBMC, patch creation
Signed-off-by: Weiqi Wang <weiqi.wang-2@postgrad.manchester.ac.uk>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2026-10-12 09:41:55 +02:00
Juergen Gross 487f7e945a tools/libxenguest: remove Mini-OS specific parts
The last Mini-OS use case of libxenguest is gone, so remove the
Mini-OS specific parts of libxenguest.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2026-09-22 11:36:15 +01:00
Andrii Sultanov a2ca4f8b98 oxenstored: Reset the watches trie on domain reconnect
oxenstored maintains two datastructures about watches; one global trie, and
one hashtable tracked per domain.  Both need keeping in sync, and right now
the global trie is not emptied when a xenbus reconnect is requested.

This is basically the same bug as XSA-330, commit 491a077ed4
("tools/ocaml/xenstored: delete watch from trie too when resetting watches"),
just tickled via another path.

Arrange for both Process.do_reset_watches() and Process.do_reconnect() to
share a common codepath for the resetting of watches and transactions.
Notably, this means that the latter now calls Connections.del_watches() which
clears the global trie too.

Connections.del_watches() already calls Connection.del_watches() so remove the
re-clearing of the state from Connection.do_reconnect().

Move History.trim() into reset_watches_and_transactions() so it's on the
common path, and place it after removing the transactions rather than before.

This is part of XSA-512 / CVE-2026-79604.

Reported-by: David Korczynski <David@Adalogics.com>
Fixes: 674ad2be40 ("xenstore: extend the xenstore ring with a 'closing' signal")
Signed-off-by: Andrii Sultanov <andriy.sultanov@vates.tech>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Andrii Sultanov <andriy.sultanov@vates.tech>
2026-09-08 12:57:23 +01:00
Andrii Sultanov 9c5a46b120 oxenstored: Factor out Process.do_reconnect()
The logic flow here is complicated.  In preparation to fix a bug, factor out
reconnecting a xenbus connection, and fold History.reconnect into it's single
caller.

No functional change.

This is part of XSA-512 / CVE-2026-79604.

Signed-off-by: Andrii Sultanov <andriy.sultanov@vates.tech>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Andrii Sultanov <andriy.sultanov@vates.tech>
2026-09-08 12:57:23 +01:00
Jan Beulich f907784c32 libacpi: drop mk_dsdt's -d / --debug option
Recent Clang complains about the "debug" static variable only ever being
written to. Drop it and the command line option controlling it.

Fixes: 19ab8356ab ("tools: remove support for running a guest with qemu-traditional")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Roger Pau Monné <roger@xenproject.org>
2026-09-07 14:11:35 +02:00
Jan Beulich f2ff80877f x86/vRTC: support century field
Both ROMBIOS and SeaBIOS (with CONFIG_QEMU=y, as we build it) blindly
assume availability of this field (at its conventional index 0x32); OVMF
at least has code to inspect FADT. Hence we ought to have supported it
virtually forever.

As the index is beyond RTC_CMOS_SIZE, leverage the padding field in
struct hvm_hw_rtc to hold its value. Update the field only when involved
values are valid BCD century specifiers. Otherwise (for VMs migrated in
from an older hypervisor) leave handling to the DM.

This makes the Linux rtc-cmos driver report y3k compatibility.

In the new rtc_check(), besides checking the new fields also check the
pre-existing pad0 field.

While extending xen-hvmctx.c:dump_rtc() also add RTC offset there.

Fixes: 4ca1612143 ("[HVM] Move RTC emulation into the hypervisor")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger@xenproject.org>
2026-09-02 15:14:08 +02:00
Jan Beulich 829d67e244 x86emul/fuzz: sanitize CR4 values
While the CPU policy is obtained from hardware, the CRn values to start
with are taken from fuzzed input. Since most CR4 bits can only be set when
the respective feature is indicated as available by CPUID, the emulator
often only checks the CR4 bit. Without sanitization, assertions like the
one in emul_test_read_xcr() (checking XSAVE support) could therefore
trigger.

Omit most paging-only bits from sanitization, as the core emulator doesn't
itself walk page tables. LA57 wants checking for the bit being used by
CANONICALIZE_MAYBE().

Reported-by: Andrew Mbugua <andrewprecious388@gmail.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2026-08-26 14:14:03 +02:00
Roger Pau Monne 79175b1390 xen/vpci: allow unaligned accesses by the hardware domain
It's possible for domains to generate unaligned PCI config space accesses
when using ECAM, and hence vPCI should support those at least for the
hardware domain.  Such unaligned accesses to the PCI config space have been
reported to come from ACPI logic.

Relax the checking in vpci_access_allowed() to allow such accesses for the
hardware domain, and fix the handling in pci_conf_{read,write}{16,32}() to
fulfill them using MMCFG.

MMCFG regions are identity exposed to the hardware domain, and hence such
unaligned accesses can only come as a result of the host having MMCFG in the
first place, as otherwise MMCFG won't be exposed to the hardware domain
either.

Note that vpci_ecam_{read,write}() already refuse accesses that cross a
device boundary unconditionally.

Reported-by: Jason Andryuk <jason.andryuk@amd.com>
Signed-off-by: Roger Pau Monné <roger@xenproject.org>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Stewart Hildebrand <stewart.hildebrand@amd.com>
2026-08-26 11:50:42 +02:00
Andrew Cooper 72b05c267e x86/emul: Rename the x86_seg_* system segments
These refer to the segments themsevles, not to the registers, even if there is
a tight coupling between the two.

No functional change.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2026-08-18 12:50:11 +01:00
Jan Beulich 0a249bcb02 x86: reduce dependencies on x86_emulate/x86_emulate.h
Split out struct x86_event to an entirely separate header, and move a few
other items describing the architecture to a new x86-types.h. With a few
forward decls of structures and with a fair number of new #include-s in
.c files, the inclusion of x86_emulate.h (and hence
x86_emulate/x86_emulate.h) can be dropped from all header files except
hvm/emulate.h; it needs additionally adding to hvm/ioreq.h though.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2026-08-13 15:12:51 +02:00
Edwin Török 0f133c8c73 libs/guest: allocate various migration arrays just once
Allocate these array just once at the start of migration,
using the maximum batch size, and free them at the end.

Signed-off-by: Edwin Török <edwin.torok@citrix.com>
Signed-off-by: Frediano Ziglio <frediano.ziglio@citrix.com>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
2026-08-11 11:07:16 +02:00
Frediano Ziglio 9b0adb928c libs/guest: move batch_pfns into a separate structure
Preparation for a followup patch "libs/guest: allocate various migration
arrays just once".

Signed-off-by: Frediano Ziglio <frediano.ziglio@citrix.com>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
2026-08-11 11:07:08 +02:00
Edwin Török a91d1616d8 libs/call: cache up to 4 pages in hypercall bounce buffers
During migration there are a lot of mmap/munmap calls,
because xc_get_pfn_type_batch() exceeds the default hypercall bounce
buffer cache size, and needs to allocate every time it is called.

munmap() is slow, especially in a PV Dom0 (takes an emulation fault),
so is best avoided.

Eventually it'd be good if the memory pool from  xmalloc_tlsf.c
was reused here, but for now make it handle the commonly encountered
sizes (so far up to 4 pages).

Signed-off-by: Edwin Török <edwin.torok@citrix.com>
Signed-off-by: Frediano Ziglio <frediano.ziglio@citrix.com>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
2026-08-10 17:09:22 +02:00
Julian Vetter 01b4b39e2e tools/ocaml: Fill arch_config for ARM in domain_getinfo{,list}()
Add the missing ARM logic, populating xen_arm_arch_domainconfig
from the raw xc_domaininfo_t the same way the x86 branch does for
xen_x86_arch_domainconfig.

Fixes: 9d683b5e37 ("tools/ocaml: Expose arch_config in domaininfo")
Fixes: 81838c9067 ("ocaml: fix arm build")
Signed-off-by: Julian Vetter <julian.vetter@vates.tech>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Teddy Astie <teddy.astie@vates.tech>
Release-Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
2026-07-29 13:38:22 +01:00
Andrew Cooper 365d2a5be3 tools/ocaml: Fix crash in Xenctrl.domain_getinfo{,list}() on ARM
The Store_field(result, 16, arch_config) sits inside an #ifdef x86, meaning
that on other architectures the pointer is not filled in.  Ocaml code then
falls over a NULL(ish) pointer (really the Val_unit used to initialise
'result') when the layout in the heap doesn't match the type system.

Rearrange alloc_domaininfo() to avoid this.  Similarly to
physinfo_arch_caps(), raise an exception if the architecture code hasn't
filled in an appropriate tag.  Move the setup of arch_domainconfig to be
common logic.

In order to simplify the addition of other architectures, remove the
arch_config variable (reusing tmp as it's touched exactly once), and rename
x86_arch_config to be arch_config so each architecture can fill in a suitable
one without needing more local variables.

Fixes: 9d683b5e37 ("tools/ocaml: Expose arch_config in domaininfo")
Fixes: 81838c9067 ("ocaml: fix arm build")
Reported-by: Julian Vetter <julian.vetter@vates.tech>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Teddy Astie <teddy.astie@vates.tech>
Release-Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
2026-07-29 13:38:22 +01:00
Jan Beulich 3179bf2931 sysctl/Flask: add preliminary check for XEN_SYSCTL_getdomaininfolist
To shield the sysctl lock from abuse by unauthorized domains, follow what
5154fdda11 ("domctl: protect locking for get_domain_state") did: Check
for permission to issue the operation against DOM_XEN in flask_sysctl().
The finer-grained xsm_getdomaininfo() later in the handling of the sub-op
remains unaltered.

In the in-tree policy respective permission therefore needs granting.

This is part of CVE-2026-62426 / XSA-499.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Daniel P. Smith <dpsmith@apertussolutions.com>
2026-07-28 12:40:10 +01:00
Syed Abdul Khaliq fd11acab3d libfsimage/iso9660: harden Rock Ridge SUSP parsing against malformed lengths
The directory and Rock Ridge / SUSP walk in iso9660_dir() derives several
lengths directly from attacker-controlled on-disk fields without validating
them.  libfsimage is used by pygrub, which parses the filesystem of an
untrusted guest disk image from dom0, so these are reachable across a trust
boundary.

Five related problems are addressed:

  * The directory record loop advances by

        idr = (char *)idr + idr->length.l

    and only stops on length.l == 0.  A record whose length is smaller than
    the fixed part of the on-disk layout cannot hold its own mandatory
    fields, yet the body still reads name_len/extent/size and computes the
    System Use area length from it.  Require length to cover at least the
    fixed record (sizeof(*idr) - sizeof(idr->name)) before entering the body.

    This is CVE-2026-42494.

  * The System Use area length is computed before the inner loop as

        rr_len = idr->length.l - idr->name_len.l
                 - sizeof(struct iso_directory_record) + sizeof(idr->name);

    in unsigned arithmetic.  If length.l is smaller than name_len.l plus the
    fixed record size, rr_len underflows to a huge value and the whole SUSP
    walk runs off the directory buffer.  Guard the subtraction and treat such
    records as having no System Use area.

    This is CVE-2026-42495.

  * Inside the loop, each entry is consumed with

        rr_len -= rr_ptr.rr->len;
        rr_ptr.ptr += rr_ptr.rr->len;

    with no lower or upper bound on the entry's own len byte.  A len of 0
    spins forever; a len greater than the remaining rr_len underflows it and
    walks past the buffer.  Validate 4 <= len <= rr_len at the top of the
    loop and stop on violation: a structurally broken entry stream cannot be
    advanced reliably, so continuing is not meaningful.

    This is CVE-2026-62423.

  * The NM handler subtracted the 5-byte SUSP/NM header from len without a
    lower-bound check, underflowing name_len (the original report).  The
    generic check above only guarantees len >= 4; NM has an extra flags byte,
    so keep an NM-specific len >= 5 check.

    This is CVE-2026-62424.

  * The CE continuation resets rr_ptr/rr_len from ce.offset and ce.size, both
    image-controlled, into the fixed single-sector RRCONT_BUF with no bounds
    check.  Reject a window that does not fit in the buffer.

    This is CVE-2026-62425.

This is XSA-497.

Signed-off-by: Syed Abdul Khaliq <abdul@bugqore.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2026-07-28 12:40:10 +01:00
Jan Beulich 59b18eb757 x86emul: support non-SIMD MOVRS
As we ignore cachability aspects of insns, they're treated like simple
MOVs.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2026-07-28 10:07:13 +02:00
Ryoji Okamoto 2fe6a869da tools/xentrace: decode RTDS priority in repl_budget records
The RTDS repl_budget trace record now contains the vCPU priority
level. Update xenalyze to account for the additional field and print
it when dumping the trace event.

Without this change, xenalyze interprets the record using the old
layout, causing the deadline and budget fields to be decoded from the
wrong offsets.

Fixes: 463b958317 ("xen:rtds: towards work conserving RTDS")
Signed-off-by: Ryoji Okamoto <okamoto@valinux.co.jp>
Reviewed-by: Teddy Astie <teddy.astie@vates.tech>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
2026-07-23 10:20:08 +02:00
Jan Beulich cf90c8a48a x86emul: V{,P}{COMPRESS,EXPAND}* can (wrongly) trigger assertion
AFL has pointed out that the op_bytes-is-not-0 assertion in common SIMD
handling can trigger for these insns. Indeed when the (relevant part of)
the controlling mask register is 0, no memory is accessed at all. Leave
op_bytes unaltered in this case, to engage the short-circuiting in common
SIMD handling when fault_suppression is true and op_bytes is 0.

While there also correct a related typo in the test harness.

Fixes: 65f82d4ce1 ("x86emul: support AVX512{F,_VBMI2} compress/expand insns")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2026-07-20 09:50:00 +02:00
Jan Beulich c5b4ba49a3 x86emul: drop wrapper C file
Move the little bit that's still left in x86/x86_emulate.c into a __XEN__
conditional in x86/x86_emulate/x86_emulate.c. Move what are roughly the
test/fuzzing harness counterparts from there into the corresponding #else.

Interestingly more recent gcc takes issue with three static const arrays
which are unused when HVM=n (noticeable in particular in the shim build).
Apparently such are diagnosed only when present in the top-level file, but
not when living in an #include-d one.

Requested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Teddy Astie <teddy.astie@vates.tech>
2026-07-16 09:17:23 +02:00
Andrii Sultanov 7b98d94e75 tools/ocaml/xb: Fix handling of requests with len = 0 for socket connections
Without this fix, the backend would be stuck waiting on the zero-sized
body until the next request comes in.

Instead return the request immediately after reading the header, there's
no need to wait for another call to .has_more_input and .input

Reported-by: George Dunlap <dunlapg@umich.edu>
Link: https://lore.kernel.org/xen-devel/CAFLBxZaeTMcF4tcV45MJdCVx4A6qbzQdjKei_Quh_iLrtARVFA@mail.gmail.com/
Signed-off-by: Andrii Sultanov <andriy.sultanov@vates.tech>
Reviewed-by: Guillaume Thouvenin <guillaume.thouvenin@vates.tech>
Release-Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
2026-07-14 12:01:46 +01:00
Frediano Ziglio fdeba9d55f libs/guest: Drop guest_data in write_batch() and fill iov directly
There is no need to store the page pointers simply to transcribe the same
information into iov later.  Drop the guest_data intermediate array.

These days, linux has a maximum limit of 1024 iovs.  Libc under the hood will
subdivide the submission if necessary, which is why our general case of 1026
submissions works.

xenforeignmemory_map() maps the requested guest memory contiguously, and
except for PV pagetable frames, we submit contiguously into the stream.  When
safe to do, merge adjacent vectors by extending iov_len, reducing the
likelihood that libc needs to subdivide the submission.

Signed-off-by: Frediano Ziglio <frediano.ziglio@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2026-07-10 19:35:49 +01:00
Frediano Ziglio 85bdb67eaa libs/ctrl: Allow writev_exact() to change the iov array
Avoid having to allocate and copy the array if a partial write happens.

Signed-off-by: Frediano Ziglio <frediano.ziglio@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2026-07-10 19:35:49 +01:00
Frediano Ziglio 03851197a7 libs/guest: Reduce number of iovecs in write_batch()
Construct all of the headers together in one block, rather than a field at a
time.  Initialise as many of the fields as possible at declaration time.

Start filling in iov[] earlier, to allow for future simplifications.

No practical change.

Signed-off-by: Frediano Ziglio <frediano.ziglio@citrix.com>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
2026-07-08 15:35:45 +01:00
Andrew Cooper 72927fc6f7 libs/guest: Allocate rec_pfns earlier in write_batch()
For reasons which escape me, rec_pfns are allocated separately to the rest of
the batch allocations.

Allocate them all together.  This will allow for future simplifications to be
performed in an incremental mannor.

No functional change.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
2026-07-08 15:35:45 +01:00
Frediano Ziglio dfb11094ae libs/guest: Use a single write_exact() in write_headers()
Reduce number of syscalls by coalescing the image and the domain headers.

Signed-off-by: Frediano Ziglio <frediano.ziglio@citrix.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Anthony PERARD <anthony.perard@vates.tech>
2026-07-08 15:35:45 +01:00
Frediano Ziglio 32204e8e19 libs/guest: Reduce number of iovecs in write_split_record()
Construct xc_sr_rhdr directly rather than in two halves.

Use size_t for combined_len, which allows the later size check to spot a few
more cases which might have truncated.

Signed-off-by: Frediano Ziglio <frediano.ziglio@citrix.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Anthony PERARD <anthony.perard@vates.tech>
2026-07-08 15:35:45 +01:00
Frediano Ziglio 42ef7f6106 libs/guest: Avoids using 2 indexes in process_page_data()
Simplify code, after the first scan of the various arrays we don't need to
keep original types and PFNs but only the ones having data.

Signed-off-by: Frediano Ziglio <frediano.ziglio@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Anthony PERARD <anthony.perard@vates.tech>
2026-07-08 15:35:45 +01:00
Jan Beulich dc21138144 libxc: drop size parameter from xc_flask_context_to_sid()
Nul-terminated strings are passed in all cases, so the strlen() can very
well be invoked by the function itself. In preparation for a hypervisor
change also include the nul terminator in the size calculation.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
Reviewed-by: Daniel P. Smith <dpsmith@apertussolutions.com>
2026-07-06 09:41:45 +02:00
Frediano Ziglio ac840e066f tools: Use posix_memalign instead of valloc for NetBSD
More similar to other implementation.
posix_memalign was adde in NetBSD 8.0, released on July 17, 2018
and went out of support on May 4, 2024.

Signed-off-by: Frediano Ziglio <frediano.ziglio@cloud.com>
Acked-by: Anthony PERARD <anthony.perard@vates.tech>
2026-07-06 09:40:17 +02:00
Andrew Cooper f0161d2d89 tools/libfsimage: Remove the XEN_FSIMAGE_FSDIR environment variable
This was reported to the security team, demonstrating that code execution
could be achieved, but without a demonstration of a priviliege boundary being
bypassed.

Still, it's a high risk path with no obvious evidence of having been used even
for debugging, so remove the environment variable and use the build time
$(libdir)/xenfsimage path only.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
Acked-by: Anthony PERARD <anthony.perard@vates.tech>
Release-Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
2026-07-03 16:52:47 +02:00
Jan Beulich ad9f564a5d tools/xen-hvmctx: shorten various format strings a little
%4.4x and alike format specifiers can be expressed shorter as %04x or, as
e.g. dump_ioapic() has it, %.4x.

In dump_fpu()'s XMM register dumping, also move away from showing bogus
xmm03 and alike. The proper register name is xmm3 for that particular
example.

Also strip trailing whitespace from lines touched.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Anthony PERARD <anthony.perard@vates.tech>
2026-07-02 08:46:34 +02:00
Jan Beulich 40e9347999 libxc: adjust string size calculations in xc_flask_{getbool_byname,setbool}()
In preparation for a hypervisor change also include the nul terminator in
the size calculations. (Note that xc_flask_getbool_byid() doesn't support
FLASK_GETBOOL's "ID being -1" variant of operation, and hence doesn't need
fiddling with.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Teddy Astie <teddy.astie@vates.tech>
Acked-by: Anthony PERARD <anthony.perard@vates.tech>
2026-07-01 14:10:46 +02:00
Jan Beulich 873bc77d3d libxc: adjust string size calculations in xc_{,de,test_}assign_dt_device()
In preparation for a hypervisor change also include the nul terminator in
the size calculations.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Teddy Astie <teddy.astie@vates.tech>
Reviewed-by: Juergen Gross <jgross@suse.com>
Acked-by: Anthony PERARD <anthony.perard@vates.tech>
2026-07-01 14:10:10 +02:00
Andrew Cooper 1383141821 Rerun ./autogen.sh for 4.23
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
2026-06-29 18:06:24 +01:00
Andrew Cooper 1a485996d9 tools/xenalyze: Fix -Werror=nonnull failure
GCC 15.2 with Alpine Linux 3.24 fails with -Werror=nonnull, complaining that
we're calling bzero(NULL, 128).

This is a legitimate diagnostic.  xenalyze has it's own error() function
shadowing the standard library one, and can in principle return when p is
NULL.

Extend the check in error() with ERR_MAX_TOLERABLE to short circuit the
variable tolerance check.

Suggested-by: Anthony PERARD <anthony.perard@vates.tech>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
2026-06-15 18:04:20 +01:00
Mykola Kvach 0656627b89 xen/arm: split DTB/initrd placement helpers
The Arm zImage loader currently computes the kernel load address and
places the DTB/initrd in one local flow.  The hardware-domain memory
allocator needs to reuse those placement rules before it chooses bank 0,
but open-coding the same calculations there would make the fix harder to
audit.

Split the existing logic into small helpers:
- kernel_zimage_place_in_bank() computes the zImage load address for a
  given bank.
- first_bank_can_fit_modules() checks the aggregate first-bank
  footprint.
- find_dtb_initrd_placement() chooses the DTB/initrd location within a
  known bank and kernel range.

Rename place_modules() to place_dtb_initrd() so the code distinguishes
the kernel image from the DTB/initrd placement area.  Also update the
comments linking the hypervisor and toolstack placement paths.

While moving the code, spell the 2MB alignment mask with MB(2) rather
than open-coding (2 << 20).  This is mechanical and keeps the generated
value unchanged.

The caller still panics in the same cases as before, so this is intended
to be behavior preserving.

Signed-off-by: Mykola Kvach <mykola_kvach@epam.com>
Reviewed-by: Michal Orzel <michal.orzel@amd.com>
Release-Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
2026-06-09 16:08:16 +01:00