The Indirect Target Selection speculative vulnerability means that indirect
branches (including RETs) are unsafe when in the first half of a cacheline.
This means it's not safe for logic using the stubs to write raw 0xc3's.
Introduce place_ret() which, for now, writes a raw 0xc3 but will contain
additional logic when return thunks are in use.
stub_selftest() doesn't strictly need to be converted as they only run on
boot, but doing so gets us a partial test of place_ret() too.
No functional change.
This is part of XSA-469 / CVE-2024-28956
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
(cherry picked from commit 2eb1132f79)
Clang 19 complains with the following error when building libxl:
libxl_utils.c:48:15: error: variable length array folded to constant array as an extension [-Werror,-Wgnu-folding-constant]
48 | char path[strlen("/local/domain") + 12];
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
Replace the usage of strlen() with sizeof, which allows the literal
string length to be known at build time. Note sizeof accounts for the
NUL terminator while strlen() didn't, hence subtract 1 from the total
size calculation.
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Frediano Ziglio <frediano.ziglio@cloud.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Anthony PERARD <anthony.perard@vates.tech>
(cherry picked from commit a7c7c3f642)
It makes no sense to request for preprocessor only output and also request
object file generation. Fix the _libxl.api-for-check target to only use
-E (preprocessor output).
Also Clang 20.0 reports an error if both options are used.
Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Fixes: 2862bf5b6c ('libxl: enforce prohibitions of internal callers')
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Anthony PERARD <anthony.perard@vates.tech>
(cherry picked from commit a235f856e4)
OCaml, in preparation for a renaming of the error string associated with
conversion failure in 'int_of_string' functions, started to issue this
warning:
File "process.ml", line 440, characters 13-28:
440 | | (Failure "int_of_string") -> reply_error "EINVAL"
^^^^^^^^^^^^^^^
Warning 52 [fragile-literal-pattern]: Code should not depend on the actual values of
this constructor's arguments. They are only for information
and may change in future versions. (See manual section 11.5)
Deal with this at the source, and instead create our own stable
ConversionFailure exception that's raised on the None case in
'int_of_string_opt'.
'c_int_of_string' is safe and does not raise such exceptions.
Signed-off-by: Andrii Sultanov <andrii.sultanov@cloud.com>
Acked-by: Christian Lindig <christian.lindig@cloud.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: c11772277f
master date: 2025-02-25 13:30:55 +0000
malloc(), when passed zero size, may return NULL (the behavior is
implementation defined). Mirror the ->gov_num check to the other two
allocations as well. Don't chance then actually using a NULL in
print_cpufreq_para().
Fixes: 75e06d089d ("xenpm: add cpu frequency control interface, through which user can")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
master commit: 6c0dc87bb0
master date: 2025-03-26 12:30:57 +0100
Infinitely retrying the rmdir() invocation makes little sense. While the
original observation was the log filling the disk (due to repeated
"Directory not empty" errors, in turn occurring for unclear reasons),
the loop wants breaking even if there was no error message being logged
(much like is done in the similar loops in libxl__remove_file() and
libxl__remove_file_or_directory()).
Fixes: c4dcbee67e ("libxl: provide libxl__remove_file et al")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Acked-by: Anthony PERARD <anthony.perard@vates.tech>
master commit: 68baeb5c48
master date: 2025-03-13 10:23:10 +0100
Channels work differently than other device types: their devid should
be -1 initially in order to distinguish them from the primary console
which has the devid of 0.
So when parsing the channel configuration, use
ARRAY_EXTEND_INIT_NODEVID() in order to avoid overwriting the devid
set by libxl_device_channel_init().
Fixes: 3a66796347 ("libxl: set channel devid when not provided by application")
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
master commit: e1ccced4af
master date: 2025-03-05 16:37:37 +0100
This is actually what the caller acquire_resource() expects on any kind
of error (the comment on top of resource_max_frames() also suggests that).
Otherwise, the caller will treat -errno as a valid value and propagate incorrect
nr_frames to the VM. As a possible consequence, a VM trying to query a resource
size of an unknown type will get the success result from the hypercall and obtain
nr_frames 4294967201.
Also, add an ASSERT_UNREACHABLE() in the default case of _acquire_resource(),
normally we won't get to this point, as an unknown type will always be rejected
earlier in resource_max_frames().
Also, update test-resource app to verify that Xen can deal with invalid
(unknown) resource type properly.
Fixes: 9244528955 ("xen/memory: Fix acquire_resource size semantics")
Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 9b87082900
master date: 2025-02-18 14:47:34 +0000
Addition of FLASK permission for this hypercall was overlooked in the
original patch. Fix it. The only VUART operation is initialization that
can occur only during domain creation.
Fixes: 86039f2e8c ("xen/arm: vpl011: Add a new domctl API to initialize vpl011")
Signed-off-by: Michal Orzel <michal.orzel@amd.com>
Acked-by: Daniel P. Smith <dpsmith@apertussolutions.com>
master commit: 29daa72e40
master date: 2025-01-08 13:05:38 +0100
ocamlmklib has special handling for C-like '-Wl,-rpath' option, but does
not know how to handle '-Wl,-rpath-link', as evidenced by warnings like:
"Unknown option
-Wl,-rpath-link=$HOME/xen/tools/ocaml/libs/eventchn/../../../../tools/libs/toollog"
Pass this option directly to the compiler with -ccopt instead.
Also pass -L directly to the linker with -ldopt. This prevents embedding absolute
paths from buildtime into binary's RPATH.
Fixes: f7b4e4558b ("tools/ocaml: Fix OCaml libs rules")
Reported-by: Fernando Rodrigues <alpha@sigmasquadron.net>
Tested-by: Fernando Rodrigues <alpha@sigmasquadron.net>
Signed-off-by: Andrii Sultanov <andrii.sultanov@cloud.com>
Acked-by: Christian Lindig <christian.lindig@cloud.com>
master commit: bf8a209915
master date: 2024-12-11 10:45:08 +0000
xc_cpuid_apply_policy() provides compatibility for migration of a pre-4.14 VM
where no CPUID data was provided in the stream.
It guesses the various max-leaf limits, based on what was true at the time of
writing, but this was not correctly adapted when speculative security issues
forced the advertisement of new feature bits. Of note are:
* LFENCE-DISPATCH, in leaf 0x80000021.eax
* BHI-CTRL, in leaf 0x7[2].edx
In both cases, a VM booted on a security-patched Xen 4.13, and then migrated
on to any newer version of Xen on the same or compatible hardware would have
these features stripped back because Xen is still editing the cpu-policy for
sanity behind the back of the toolstack.
For VMs using BHI_DIS_S to mitigate Native-BHI, this resulted in a failure to
restore the guests MSR_SPEC_CTRL setting:
(XEN) HVM d7v0 load MSR 0x48 with value 0x401 failed
(XEN) HVM7 restore: failed to load entry 20/0 rc -6
Fixes: e9b4fe2636 ("x86/cpuid: support LFENCE always serialising CPUID bit")
Fixes: f3709b15fc ("x86/cpuid: Infrastructure for cpuid word 7:2.edx")
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
master commit: 28301682f4
master date: 2024-12-03 12:20:41 +0000
While result values and other status flags are unaffected as long as we
can ignore the case of registers having their upper 32 bits non-zero
outside of 64-bit mode, EFLAGS.SF may obtain a wrong value when we
mistakenly re-execute the original insn with VEX.W set.
Note that guest the memory access, if any, is correctly carried out as
32-bit regardless of VEX.W. The emulator-local memory operand will be
accessed as a 64-bit quantity, but it is pre-initialised to zero so no
internal state can leak.
Fixes: 771daacd19 ("x86emul: support BMI1 insns")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 1179d51dcb
master date: 2024-11-14 13:00:57 +0100
Xen 4.1 is more than a decade stale now. Use the same mechanism as elsewhere
in the tree to get the current version number.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Christian Lindig <christian.lindig@cloud.com>
Reviewed-by: Edwin Török <edwin.torok@cloud.com>
master commit: 1965e9a930
master date: 2024-08-23 15:02:27 +0100
These days, `ocamlopt -h` asks you whether you meant --help instead, meaning
that the $(shell ) invocation here isn't going end up containing '-g'.
Make it unconditional, like it is in OCAMLCFLAGS already.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Christian Lindig <christian.lindig@cloud.com>
Reviewed-by: Edwin Török <edwin.torok@cloud.com>
master commit: 126293eae6
master date: 2024-08-23 15:02:27 +0100
It's very rude for a library to play with signals behind the back of the
application, no matter ones views on the default behaviour of SIGPIPE under
POSIX. Even if the application doesn't care about the xenstored socket, it my
care about others.
This logic has existed since xenstore/xenstored was originally added in commit
29c9e570b1 ("Add xenstore daemon and library") in 2005.
It's also unnecessary. Pass MSG_NOSIGNAL when talking to xenstored over a
pipe (to avoid sucumbing to SIGPIPE if xenstored has crashed), and forgo any
playing with the signal disposition.
This has a side benefit of saving 2 syscalls per xenstore request.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
master commit: a17b6db9b0
master date: 2024-07-23 15:11:27 +0100
With the input data now conveniently arranged, use writev()/sendmsg() instead
of decomposing it into write() calls.
This causes all requests to be submitted with a single system call, rather
than at least two. While in principle short writes can occur, the chances of
it happening are slim given that most xenbus comms are only a handful of
bytes.
Nevertheless, provide {writev,sendmsg}_exact() wrappers which take care of
resubmitting on EINTR or short write.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
master commit: ebaeb0c64a
master date: 2024-07-23 15:11:27 +0100
We would like to writev() the whole outgoing message, but this is hard given
the current need to prepend the locally-constructed xsd_sockmsg.
Instead, have the caller provide xsd_sockmsg in iovec[0]. This in turn drops
the 't' and 'type' parameters from xs_talkv().
Note that xs_talkv() may alter the iovec structure. This may happen when
writev() is really used under the covers, and it's preferable to having the
lower levels need to duplicate the iovec to edit it upon encountering a short
write. xs_directory_part() is the only function impacted by this, and it's
easy to rearrange to be compatible.
No functional change.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
master commit: e2a93bed8b
master date: 2024-07-23 15:11:27 +0100
If the sum of iov element lengths overflows, the XENSTORE_PAYLOAD_MAX can
pass, after which we'll write 4G of data with a good-looking length field, and
the remainder of the payload will be interpreted as subsequent commands.
Check each iov element length for XENSTORE_PAYLOAD_MAX before accmulating it.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
master commit: 42db2deb5e
master date: 2024-07-23 15:11:27 +0100
xen-hvmcrash would previously save records, overwrite the instruction
pointer with a bogus value, and then restore them to crash a domain
just enough to cause the guest OS to memdump.
This approach is found to be unreliable when tested on a guest running
Windows 10 x64, with some executions doing nothing at all.
Another approach would be to trigger NMIs. This approach is found to be
unreliable when tested on Linux (Ubuntu 22.04), as Linux will ignore
NMIs if it is not configured to handle such.
Injecting a double fault abort to all vCPUs is found to be more
reliable at crashing and invoking memdumps from Windows and Linux
domains.
This patch modifies the xen-hvmcrash tool to inject #DF to all vCPUs
belonging to the specified domain, instead of overwriting RIP.
Signed-off-by: Matthew Barnes <matthew.barnes@cloud.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: e42e4d8c3e
master date: 2024-07-22 10:50:03 +0100
xl/libxl memory is leaking into a PVH guest through uninitialized
portions of the ACPI tables.
Use libxl_zalloc() to obtain zero-ed memory to avoid this issue.
This is XSA-464 / CVE-2024-45819.
Signed-off-by: Jason Andryuk <jason.andryuk@amd.com>
Fixes: 14c0d328da ("libxl/acpi: Build ACPI tables for HVMlite guests")
Reviewed-by: Jan Beulich <jbeulich@suse.com>
master commit: 0bfe567b58
master date: 2024-11-12 13:32:45 +0100
Drop explicit {evex} pseudo-prefixes. New gas (validly) complains when
they're used on things other than instructions. Our use was potentially
ahead of macro invocations - see simd.h's "override" macro.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 3c09288298
master date: 2024-09-06 08:41:18 +0200
When built with ASAN, "xl dmesg" crashes in the "printf("%s", line)"
call in main_dmesg(). ASAN reports a heap buffer overflow: an
off-by-one access to cr->buffer.
The readconsole sysctl copies up to count characters into the buffer,
but it does not add a null character at the end. Despite the
documentation of libxl_xen_console_read_line(), line_r is not
nul-terminated if 16384 characters were copied to the buffer.
Fix this by asking xc_readconsolering() to fill the buffer up to size
- 1. As the number of characters in the buffer is only needed in
libxl_xen_console_read_line(), make it a local variable there instead
of part of the libxl__xen_console_reader struct.
Fixes: 4024bae739 ("xl: Add subcommand 'xl dmesg'")
Reported-by: Edwin Török <edwin.torok@cloud.com>
Signed-off-by: Javi Merino <javi.merino@cloud.com>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
master commit: bb03169bcb
master date: 2024-09-03 10:53:44 +0100
In "xl help", the output includes this line:
vsnd-list List virtual display devices for a domain
This should obviously say "sound devices" instead of "display devices".
Signed-off-by: John E. Krokes <mag@netherworld.org>
Reviewed-by: Juergen Gross <jgross@suse.com>
Acked-by: Anthony PERARD <anthony.perard@vates.tech>
master commit: 09226d165b
master date: 2024-08-14 08:49:44 +0200
Currently, lsevtchn aborts its event channel enumeration when it hits
an event channel that is owned by Xen.
lsevtchn does not distinguish between different hypercall errors, which
results in lsevtchn missing potential relevant event channels with
higher port numbers.
Use the errno macro to distinguish between hypercall errors, and
continue event channel enumeration if the hypercall error is not
critical to enumeration.
Signed-off-by: Matthew Barnes <matthew.barnes@cloud.com>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
master commit: e92a453c8d
master date: 2024-08-02 08:43:57 +0200
set_cloexec() had a bit too much copy&pate from setnonblock(), and
insufficient testing on ancient versions of Linux...
As written (emulating ancient linux by undef'ing O_CLOEXEC), strace shows:
open("/dev/xen/xenbus", O_RDWR) = 3
fcntl(3, F_GETFL) = 0x8002 (flags O_RDWR|O_LARGEFILE)
fcntl(3, 0x8003 /* F_??? */, 0x7ffe4a771d90) = -1 EINVAL (Invalid argument)
close(3) = 0
which is obviously nonsense.
Switch F_GETFL -> F_GETFD, and fix the second invocation to use F_SETFD. With
this, strace is rather happer:
open("/dev/xen/xenbus", O_RDWR) = 3
fcntl(3, F_GETFD) = 0
fcntl(3, F_SETFD, FD_CLOEXEC) = 0
Fixes: bf7c146470 ("tools/libxs: Fix CLOEXEC handling in get_dev()")
Reported-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
master commit: 37810b52d0
master date: 2024-07-09 15:32:18 +0100
xs_fileno() opens a pipe on first use to communicate between the watch thread
and the main thread. Nothing ever sets CLOEXEC on the file descriptors.
Check for the availability of the pipe2() function with configure. Despite
starting life as Linux-only, FreeBSD and NetBSD have gained it.
When pipe2() isn't available, try our best with pipe() and set_cloexec().
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Acked-by: Anthony PERARD <anthony.perard@vates.tech>
master commit: a2ff677852
master date: 2024-07-02 10:52:59 +0100
get_socket() opens a socket, then uses fcntl() to set CLOEXEC. This is racy
with exec().
Open the socket with SOCK_CLOEXEC. Use the same compatibility strategy as
O_CLOEXEC on ancient versions of Linux.
Reported-by: Frediano Ziglio <frediano.ziglio@cloud.com>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Acked-by: Anthony PERARD <anthony.perard@vates.tech>
master commit: 1957dd6aff
master date: 2024-07-02 10:51:11 +0100
Move the O_CLOEXEC compatibility outside of an #ifdef USE_PTHREAD block.
Introduce set_cloexec() to wrap fcntl() setting FD_CLOEXEC. It will be reused
for other CLOEXEC fixes too.
Use set_cloexec() when O_CLOEXEC isn't available as a best-effort fallback.
Fixes: f4f2f3402b ("tools/libxs: Open /dev/xen/xenbus fds as O_CLOEXEC")
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Acked-by: Anthony PERARD <anthony.perard@vates.tech>
master commit: bf7c146470
master date: 2024-07-02 10:51:06 +0100
xc_dom_alloc_segment() is passed a size in bytes, calculates a size in pages
from it, then fills in the new segment information with a bytes value
re-calculated from the number of pages.
This causes the module information given to the guest (MB, or PVH) to have
incorrect sizes; specifically, sizes rounded up to the next page.
This in turn is problematic for Xen. When Xen finds a gzipped module, it
peeks at the end metadata to judge the decompressed size, which is a -4
backreference from the reported end of the module.
Fill in seg->vend using the correct number of bytes.
Fixes: ea7c8a3d0e ("libxc: reorganize domain builder guest memory allocator")
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Anthony PERARD <anthony.perard@vates.tech>
master commit: 4c3a618b0a
master date: 2024-07-02 10:50:18 +0100
There are no more users, and we want to disuade people from introducing new
users just for sd_notify() and friends. Drop the dependency.
We still want the overall --with{,out}-systemd to gate the generation of the
service/unit/mount/etc files.
Rerun autogen.sh, and mark the dependency as removed in the build containers.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Acked-by: Christian Lindig <christian.lindig@cloud.com>
tools: (Actually) drop libsystemd as a dependency
When reinstating some of systemd.m4 between v1 and v2, I reintroduced a little
too much. While {c,o}xenstored are indeed no longer linked against
libsystemd, ./configure still looks for it.
Drop this too.
Fixes: ae26101f6b ("tools: Drop libsystemd as a dependency")
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
master commit: ae26101f6b
master date: 2024-05-23 15:04:40 +0100
master commit: 6ef4fa1e7f
master date: 2024-05-30 12:15:25 +0100
... in order to avoid linking against the whole of libsystemd.
Only minimal changes to the upstream copy, to function as a drop-in
replacement for sd_notify() and as a header-only library.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Acked-by: Christian Lindig <christian.lindig@cloud.com>
master commit: 78510f3a15
master date: 2024-05-23 15:04:40 +0100
master commit: 78510f3a15
master date: 2024-05-23 15:04:40 +0100
In case a test is failing in test-xenstore, let the tool exit with an
exit status other than 0.
Fix a typo in an error message.
Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Fixes: 3afc5e4a5b ("tools/tests: add xenstore testing framework")
Signed-off-by: Juergen Gross <jgross@suse.com>
master commit: 2d4ba20559
master date: 2024-05-02 18:15:46 +0100
Today test-xenstore will write nodes with 3000 bytes node data. This
size is exceeding the default quota for the allowed node size. While
working in dom0 with C-xenstored, OCAML-xenstored does not like that.
Use a size of 2000 instead, which is lower than the allowed default
node size of 2048.
Fixes: 3afc5e4a5b ("tools/tests: add xenstore testing framework")
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 642005e310
master date: 2024-05-02 18:15:31 +0100
In compare_cpu_pct(), there is a double -> unsigned long long converion when
calling compare(). In C, this discards the fractional part, resulting in an
out-of order sorting such as:
NAME STATE CPU(sec) CPU(%)
xendd --b--- 4020 5.7
icecream --b--- 2600 3.8
Domain-0 -----r 1060 1.5
neon --b--- 827 1.1
cheese --b--- 225 0.7
pizza --b--- 359 0.5
cassini --b--- 490 0.4
fusilli --b--- 159 0.2
bob --b--- 502 0.2
blender --b--- 121 0.2
bread --b--- 69 0.1
chickpea --b--- 67 0.1
lentil --b--- 67 0.1
Introduce compare_dbl() function and update compare_cpu_pct() to call it.
Fixes: 49839b535b ("Add xenstat framework.")
Signed-off-by: Leigh Brown <leigh@solinno.co.uk>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: e27fc7d15e
master date: 2024-05-15 19:59:52 +0100
If xenstored runs out of memory it is possible for it to fail operations
that should succeed. libxl wasn't robust against this, and could fail
to ensure that the TTY path of a non-initial console was created and
read-only for guests. This doesn't qualify for an XSA because guests
should not be able to run xenstored out of memory, but it still needs to
be fixed.
Add the missing error checks to ensure that all errors are properly
handled and that at no point can a guest make the TTY path of its
frontend directory writable.
Signed-off-by: Demi Marie Obenour <demi@invisiblethingslab.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
master commit: 531d3bea5e
master date: 2024-05-11 00:13:43 +0100
libxl passes some information to libacpi to create the ACPI table for a PVH
guest, and among that information it's a bitmap of which vCPUs are online
which can be less than the maximum number of vCPUs assigned to the domain.
While the population of the bitmap is done correctly for HVM based on the
number of online vCPUs, for PVH the population of the bitmap is done based on
the number of maximum vCPUs allowed. This leads to all local APIC entries in
the MADT being set as enabled, which contradicts the data in xenstore if vCPUs
is different than maximum vCPUs.
Fix by copying the internal libxl bitmap that's populated based on the vCPUs
parameter.
Reported-by: Arthur Borsboom <arthurborsboom@gmail.com>
Link: https://gitlab.com/libvirt/libvirt/-/issues/399
Reported-by: Leigh Brown <leigh@solinno.co.uk>
Fixes: 14c0d328da ('libxl/acpi: Build ACPI tables for HVMlite guests')
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Tested-by: Leigh Brown <leigh@solinno.co.uk>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 5cc7347b04
master date: 2024-05-11 00:13:43 +0100
Right now, Xen returns -ENOENT for both "the provided blob isn't correct for
this CPU", and "the blob isn't newer than what's loaded".
This in turn causes xen-ucode to exit with an error, when "nothing to do" is
more commonly a success condition.
Handle EEXIST specially and exit cleanly.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
master commit: 648db37a15
master date: 2024-05-09 18:19:49 +0100
An XSM hook for get_dom0_console is currently missing. Using XSM with
a PVH dom0 shows:
(XEN) FLASK: Denying unknown platform_op: 64.
Wire up the hook, and allow it for dom0.
Fixes: 4dd160583c ("x86/platform: introduce hypercall to get initial video console settings")
Signed-off-by: Jason Andryuk <jason.andryuk@amd.com>
Acked-by: Daniel P. Smith <dpsmith@apertussolutions.com>
master commit: 647f7e50eb
master date: 2024-04-30 08:33:41 +0200
A TSX Abort is one option mitigate Native-BHI, but a guest kernel doesn't get
to see this if Xen has turned RTM off using MSR_TSX_{CTRL,FORCE_ABORT}.
Therefore, the meaning of RTM_ALWAYS_ABORT has been adjusted to "XBEGIN won't
fault", and it should be exposed to guests so they can make a better decision.
Expose it in the max policy for any RTM-capable system. Offer it by default
only if RTM has been disabled.
Update test-tsx to account for this new meaning. While adjusting the logic in
test_guest_policies(), take the opportunity to use feature names (now they're
available) to make the logic easier to follow.
This is part of XSA-456 / CVE-2024-2201.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
(cherry picked from commit c94e210592)
Right now, test-resource always creates HVM Shadow guests. But if Xen has
SHADOW compiled out, running the test yields:
$./test-resource
XENMEM_acquire_resource tests
Test x86 PV
Created d1
Test grant table
Test x86 PVH
Skip: 95 - Operation not supported
and doesn't really test HVM guests, but doesn't fail either.
There's nothing paging-mode-specific about this test, so default to HAP if
possible and provide a more specific message if neither HAP or Shadow are
available.
As we've got physinfo to hand, also provide more specific message about the
absence of PV or HVM support.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
master commit: 0263dc9069
master date: 2024-03-01 20:14:19 +0000
Now that we no longer have a hashtable inside we can make Quota.t pure, and
push the mutable update to its callers. Store.t already had a mutable Quota.t
field.
No functional change.
Signed-off-by: Edwin Török <edwin.torok@cloud.com>
Acked-by: Christian Lindig <christian.lindig@cloud.com>
(cherry picked from commit 098d868e52)
On a stress test running 1000 VMs flamegraphs have shown that
`oxenstored` spends a large amount of time in `Hashtbl.copy` and the GC.
Hashtable complexity:
* read/write: O(1) average
* copy: O(domains) -- copying the entire table
Map complexity:
* read/write: O(log n) worst case
* copy: O(1) -- a word copy
We always perform at least one 'copy' when processing each xenstore
packet (regardless whether it is a readonly operation or inside a
transaction or not), so the actual complexity per packet is:
* Hashtbl: O(domains)
* Map: O(log domains)
Maps are the clear winner, and a better fit for the immutable xenstore
tree.
Signed-off-by: Edwin Török <edwin.torok@cloud.com>
Acked-by: Christian Lindig <christian.lindig@cloud.com>
(cherry picked from commit b6cf604207)
tools/oxenstored: Re-format
Rerun make format.
Fixes: b6cf604207 ("tools/oxenstored: Use Map instead of Hashtbl for quotas")
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Edwin Török <edwin.torok@cloud.com>
(cherry picked from commit 8f85af65af)
Andrew Cooper
Roger Pau Monne
Jan Beulich
Andrii Sultanov
Juergen Gross
Oleksandr Tyshchenko
Michal Orzel
Marek Marczykowski-Górecki
Matthew Barnes
Jason Andryuk
Javi Merino
John E. Krokes
Leigh Brown
Demi Marie Obenour
Edwin Török