Commit Graph
34181 Commits
Author SHA1 Message Date
Roger Pau Monne 86e54bea2b init/FreeBSD: remove xendriverdomain_precmd
...because it's empty. While there also rename xendriverdomain_startcmd to
xendriverdomain_start in order to match the nomenclature of the file.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
[ wei: fix up minor error ]
Signed-off-by: Wei Liu <wei.liu2@citrix.com>

(cherry picked from commit 29b968e46b)
2017-01-04 17:06:36 +00:00
Roger Pau Monne e7ad85ef7e init/FreeBSD: set correct PATH for xl devd
FreeBSD init scripts don't have /usr/local/{bin/sbin} in it's PATH, which
prevents `xl devd` from working properly since hotplug scripts require the set
of xenstore cli tools to be in PATH.

While there also fix the usage of --pidfile, which according to the xl help
doesn't use "=", and add braces around XLDEVD_PIDFILE.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
(cherry picked from commit 1d52073334)
2017-01-04 17:06:36 +00:00
Anshul Makkar bdbfca040a xsm: allow relevant permission during migrate and gpu-passthrough.
During guest migrate allow permission to prevent
spurious page faults.
Prevents these errors:
d73: Non-privileged (73) attempt to map I/O space 00000000

avc: denied  { set_misc_info } for domid=0 target=11
scontext=system_u:system_r:dom0_t
tcontext=system_u:system_r:domU_t tclass=domain

GPU passthrough for hvm guest:
avc:  denied  { send_irq } for domid=0 target=10
scontext=system_u:system_r:dom0_t
tcontext=system_u:system_r:domU_t tclass=hvm

Signed-off-by: Anshul Makkar <anshul.makkar@citrix.com>
Acked-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
(cherry picked from commit f04722f78b)
2017-01-04 17:02:28 +00:00
Wei Liu 443264ea12 libxl: init_acpi_config should return rc in exit path, and set to 0 on success
init_acpi_config should return rc in exit path

... otherwise it returns 0 even if the function fails.

Coverity-ID: 1397121

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
(cherry picked from commit 1361db0ed3)

AND:

set rc to 0 in init_acpi_config in success path

xc_doamin_getinfo returns >=0 in success path, and if there is no vnode
configured, that rc will be returned to caller, which indicates error.

Fix that by setting rc to 0 in success path.

Reported-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
(cherry picked from commit 08ccb46924)

Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
2017-01-04 17:00:36 +00:00
Andrew Cooper d57590205e x86/emul: add likely()/unlikely() to test harness
Fix a build problem introduced in c/s 122dd9575c "x86emul:
in_longmode() should not ignore ->read_msr() errors" by providing an
implementation of likely()/unlikely().

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>

Cherrypicked out of:

master commit: 3e84c8da7d
master date: 2016-12-02 17:23:01 +0000
2016-12-22 16:23:37 +01:00
Jan Beulich 24ccfc3327 x86/HVM: add missing NULL check before using VMFUNC hook
This is CVE-2016-10025 / XSA-203.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 74dcd0ce6f
master date: 2016-12-21 16:47:19 +0100
2016-12-21 17:41:20 +01:00
Jan Beulich 7628c7efb4 x86: force EFLAGS.IF on when exiting to PV guests
Guest kernels modifying instructions in the process of being emulated
for another of their vCPU-s may effect EFLAGS.IF to be cleared upon
next exiting to guest context, by converting the being emulated
instruction to CLI (at the right point in time). Prevent any such bad
effects by always forcing EFLAGS.IF on. And to cover hypothetical other
similar issues, also force EFLAGS.{IOPL,NT,VM} to zero.

This is CVE-2016-10024 / XSA-202.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 0e47f92b07
master date: 2016-12-21 16:46:13 +0100
2016-12-21 17:40:37 +01:00
Andrew Cooper b996efb238 x86/emul: Correct the handling of eflags with SYSCALL
A singlestep #DB is determined by the resulting eflags value from the
execution of SYSCALL, not the original eflags value.

By using the original eflags value, we negate the guest kernels attempt to
protect itself from a privilege escalation by masking TF.

Have the SYSCALL emulation recalculate tf after the instruction is complete.

This is XSA-204

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2016-12-19 15:46:00 +00:00
Ian Jackson 7967dafe6a QEMU_TAG update 2016-12-07 16:53:21 +00:00
Jan Beulich 1f4ea16035 update Xen version to 4.8.1-pre 2016-12-06 10:14:32 +01:00
Ian Jackson b03cee7319 Version numbers: Finalise 4.8.0.
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
RELEASE-4.8.0
2016-12-05 12:03:27 +00:00
Ian Jackson d7224f5e00 Config.mk: Update subtrees to 4.8.0 release tags
No functional change.

All these tags have been pushed to the corresponding trees on xenbits.

Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
2016-12-05 12:00:59 +00:00
Ian Jackson a7a578ce6b Config.mk: Drop stale QEMU_TRADITIONAL_REVISION commentary
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
4.8.0-rc8
2016-11-29 18:05:48 +00:00
Ian Jackson a9aa71a5ed Merge branch 'staging' of xenbits.xen.org:/home/xen/git/xen into staging 2016-11-29 16:54:30 +00:00
Ian Jackson 91bdabab73 Update QEMU_TRADITIONAL_REVISION and QEMU_UPSTREAM_REVISION to -rc7
These commits include the fix for XSA-197.

Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
4.8.0-rc7
2016-11-29 16:41:32 +00:00
Dario Faggioli 3a782c7603 credit2: make runqueues be per-socket by default
Benchmarks have shown that per-socket runqueues arrangement
behaves better (e.g., we achieve better load balancing)
than the current per-core default.

Here's an example (coming from
https://lists.xen.org/archives/html/xen-devel/2016-06/msg02287.html ):

|=======================================|
| XEN BUILD TIME, LOW LOAD, NO NOISE    |
|---------------------------------------|
|       runq=core   runq=socket         |
|         35.200       33.433           |
|---------------------------------------|------------------------------|
| XEN BUILD TIME, HIGH LOAD, NO NOISE   | IPERF, HIGH LOAD, NO NOISE   |
|---------------------------------------|------------------------------|
|       runq=core   runq=socket         |     runq=core runq=socket    |
|         18.013       18.530           |       23.200     23.466      |
|---------------------------------------|------------------------------|
| XEN BUILD TIME, LOW LOAD, WITH NOISE  |
|-------------------------------------  |
|       runq=core   runq=socket         |
|         45.866       39.493           |
|---------------------------------------|------------------------------|
| XEN BUILD TIME, HIGH LOAD, WITH NOISE | IPERF, HIGH LOAD, WITH NOISE |
|---------------------------------------|------------------------------|
|       runq=core   runq=socket         |     runq=core runq=socket    |
|         36.840       29.080           |       19.967     21.000      |
|=======================================|==============================|

The only reason why we went for per-core, initially, was to
introduce some form of hyperthreading support. Now we have
hyperthreading support, independently from how runqueues
are organized (9bb9c7388 "xen: credit2: implement true SMT
support"), and thus we can switch to per-socket.

Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Acked-by: George Dunlap <george.dunlap@eu.citrix.com>
Release-acked-by: Wei Liu <wei.liu2@citrix.com>
2016-11-29 16:01:03 +01:00
Julien Grall d066b5b9ba libacpi: fix compilation when cross building the tools
The tools (such as mk_dsdt) can be cross-built when it may not be
desirable to build them on the target.

The commit c4ac1077 "libxl/arm: Generate static ACPI DSDT table"
introduced support of ARM64 in mk_dsdt but also break cross-building
tools because the ACPI tables are not correct.

While mk_dsdt should generate ACPI table for the target architecture, it
currently generates the one for the host. This is because the source
code contains reference to the host architecture (__aarch64__,
__x86_64__, __i386__) when it should be the target architecture.

Replace all __aarch64__, __x86_64__, __i386__ by the corresponding
CONFIG_*.

Also expose the CONFIG_* to the source code as the currently only
exposed to the Makefile.

Reported-by: Andrii Anisov <andrii.anisov@gmail.com>
Suggested-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Release-acked-by: Wei Liu <wei.liu2@citrix.com>
2016-11-29 16:00:48 +01:00
Wei Chen 6aaff7b407 arm32: handle async aborts delivered while at HYP
If guest generates an asynchronous abort and then traps into HYP
(by HVC or IRQ) before the abort has been delivered, the hypervisor
could not catch it, because the PSTATE.A bit is masked all the time
in hypervisor. So this asynchronous abort may be slipped to next
running guest with PSTATE.A bit unmasked.

In order to avoid this, it is necessary to take the abort at HYP, by
clearing the PSTATE.A bit. In this patch, we unmask the PSTATE.A bit
to open a window to catch guest-generated asynchronous abort in all
Guest -> HYP switch paths. If we caught such asynchronous abort in
checking window, the HYP data abort exception will be triggered and
the abort source guest will be crashed.

This is part of XSA-201.

Signed-off-by: Wei Chen <Wei.Chen@arm.com>
Reviewed-by: Julien Grall <julien.grall@arm.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
2016-11-29 15:59:55 +01:00
Wei Chen f8c6a9334b arm: crash the guest when it traps on external abort
If we spot a data or prefetch abort bearing the ESR_EL2.EA bit set, we
know that this is an external abort, and that should crash the guest.

This is part of XSA-201.

Signed-off-by: Wei Chen <Wei.Chen@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Steve Capper <steve.capper@arm.com>
Reviewed-by: Julien Grall <Julien.Grall@arm.com>
2016-11-29 15:59:26 +01:00
Wei Chen 36008800e8 arm64: handle async aborts delivered while at EL2
If EL1 generates an asynchronous abort and then traps into EL2
(by HVC or IRQ) before the abort has been delivered, the hypervisor
could not catch it, because the PSTATE.A bit is masked all the time
in hypervisor. So this asynchronous abort may be slipped to next
running guest with PSTATE.A bit unmasked.

In order to avoid this, it is necessary to take the abort at EL2, by
clearing the PSTATE.A bit. In this patch, we unmask the PSTATE.A bit
to open a window to catch guest-generated asynchronous abort in all
EL1 -> EL2 swich paths. If we catched such asynchronous abort in
checking window, the hyp_error exception will be triggered and the
abort source guest will be crashed.

This is part of XSA-201.

Signed-off-by: Wei Chen <Wei.Chen@arm.com>
Reviewed-by: Julien Grall <julien.grall@arm.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
2016-11-29 15:58:57 +01:00
Wei Chen 2cf7d2bafb arm64: handle guest-generated EL1 asynchronous abort
In current code, when the hypervisor receives an asynchronous abort
from a guest, the hypervisor will do panic, the host will be down.
We have to prevent such security issue, so, in this patch we crash
the guest, when the hypervisor receives an asynchronous abort from
the guest.

This is part of XSA-201.

Signed-off-by: Wei Chen <Wei.Chen@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Steve Capper <steve.capper@arm.com>
Reviewed-by: Julien Grall <Julien.Grall@arm.com>
2016-11-29 15:57:52 +01:00
Andrew Cooper 99a10da1b4 x86/cpu: reposition stack alignment check
As identified during review, using BUG_ON() before `lidt` will result in a
triple fault, even on APs.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Release-acked-by: Wei Liu <wei.liu2@citrix.com>
2016-11-28 09:17:00 +01:00
Juergen Gross 1c524dd494 remove reference to xensource.com
xen/include/public/hvm/pvdrivers.h contains a reference to
xen-devel@lists.xensource.com. Replace it by the correct address
xen-devel@lists.xenproject.org

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2016-11-25 14:32:44 +01:00
Dario Faggioli d865f39733 blkif: kill some repetitions in protocol description
The whole block describing multiqueue support was repeated
two times.

There also was some repetition in the description of the
'discard-enable' property.

Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Release-acked-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Konrad Rzeszutek Will <Konrad.wilk@oracle.com>
2016-11-25 14:32:19 +01:00
Jan Beulich cc53a74291 x86emul: CMOVcc always writes its destination
This would be benign if there wasn't the zero-extending side effect of
32-bit operations in 64-bit mode.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Wei Liu <wei.liu2@citrix.com>
2016-11-25 14:31:50 +01:00
Jan Beulich bffd3752b7 x86: re-add stack alignment check
Commit 279840d5ea ("x86/boot: install trap handlers much earlier on
boot"), perhaps not really intentionally, removed this check. Add it
back,
- preventing it from triggering before any output is set up,
- accompanying it with a (weaker, due to its open coding of what
  get_stack_bottom() does) build time check.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Wei Liu <wei.liu2@citrix.com>
2016-11-25 14:30:58 +01:00
Andrew Cooper 892d191df6 x86/vmx: Don't deliver #MC with an error code
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Kevin Tian <kevin.tian@intel.com>
Release-acked-by: Wei Liu <wei.liu2@citrix.com>
2016-11-25 10:48:20 +00:00
Andrew Cooper 9586cba338 x86/emul: Don't deliver #UD with an error code
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Release-acked-by: Wei Liu <wei.liu2@citrix.com>
2016-11-25 10:48:10 +00:00
Jan Beulich 647c7bd445 x86/SVM: don't deliver #GP without error code
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Wei Liu <wei.liu2@citrix.com>
2016-11-25 09:46:32 +01:00
Andrew Cooper 7b5266abfd x86/hvm: Rename hvm_emulate_init() and hvm_emulate_prepare() for clarity
* Move hvm_emulate_init() to immediately after hvm_emulate_prepare(), as they
   are very closely related.
 * Rename hvm_emulate_prepare() to hvm_emulate_init_once() and
   hvm_emulate_init() to hvm_emulate_init_per_insn() to make it clearer how to
   and when to use them.

No functional change.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Release-acked-by: Wei Liu <wei.liu2@citrix.com>
2016-11-23 17:18:31 +00:00
Roger Pau Monne 45434adc3c libxl: fix creation of pkgconf install dir
When PKG_INSTALLDIR was introduced the creation of the previous pkgconf install
directory was not changed. Fix this by correctly using PKG_INSTALLDIR for the
directory creation in libxl Makefile.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Release-acked-by: Wei Liu <wei.liu2@citrix.com>
2016-11-23 17:07:07 +00:00
Jan Beulich 122dd9575c x86emul: in_longmode() should not ignore ->read_msr() errors
All present hook implementations succeed for EFER, but we shouldn't
really build on this being the case.

Suggested-by: George Dunlap <george.dunlap@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Wei Liu <wei.liu2@citrix.com>
2016-11-23 15:27:47 +01:00
Jan Beulich 0af1b466c4 x86emul: simplify DstBitBase handling code
..., at once making it more obvious that even in the negative bit
offset case the resulting bit offset to be used by the inlined
instructions will always be constrained to the operand size of the
original instruction.

Also add a test case which would have failed without the XSA-195 fix.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Wei Liu <wei.liu2@citrix.com>
2016-11-23 15:27:17 +01:00
Jan Beulich 13a8f97d42 x86/HVM: correct error code writing during task switch
Whether to write 32 or just 16 bits depends on the D bit of the target
CS. The width of the stack pointer to use depends on the B bit of the
target SS.

Also avoid using the no-fault copying routine.

Finally avoid using yet another struct segment_register variable here.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Wei Liu <wei.liu2@citrix.com>
2016-11-23 15:26:51 +01:00
Jan Beulich bac3e8e0f5 x86/HVM: limit writes to outgoing TSS during task switch
The only fields modified are EIP, EFLAGS, GPRs, and segment selectors.
CR3 in particular is not supposed to be updated.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Wei Liu <wei.liu2@citrix.com>
2016-11-23 15:26:11 +01:00
Jan Beulich db153db088 x86/HVM: limit writes to incoming TSS during task switch
The only field modified (and even that conditionally) is the back link.
Write only that field, and only when it actually has been written to.

Take the opportunity and also ditch the pointless initializer from the
"tss" local variable, which gets completely filled anyway by reading
from guest memory.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Wei Liu <wei.liu2@citrix.com>
2016-11-23 15:25:35 +01:00
Roger Pau Monne e5745b86e6 libelf: fix symtab/strtab loading for 32bit domains
Commit ed04ca introduced a bug in the symtab/strtab loading for 32bit
guests, that corrupted the section headers array due to the padding
introduced by the elf_shdr union.

The Elf section header array on 32bit should be accessible as an array of
Elf32_Shdr elements, and the union with Elf64_Shdr done in elf_shdr was
breaking this due to size differences between Elf32_Shdr and Elf64_Shdr.

Fix this by copying each section header one by one, and using the proper
size depending on the bitness of the guest kernel. While there, also fix
a couple of consistency issues, by making sure we always use the sizes of
our local versions of the ELF header and the ELF sections headers.

Reported-by: Brian Marcotte <marcotte@panix.com>
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Release-acked-by: Wei Liu <wei.liu2@citrix.com>
2016-11-23 12:59:47 +00:00
Jan Beulich 986f790e01 x86/memshr: properly check grant references
They need to be range checked against the current table limit in any
event.

Reported-by: Huawei PSIRT <psirt@huawei.com>

Move the code to where it belongs, eliminating a number of duplicate
definitions. Add locking. Produce proper error codes, and consume them
instead of making one up. Check grant type. Convert parameter types at
once.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Tamas K Lengyel <tamas@tklengyel.com>
Release-acked-by: Wei Liu <wei.liu2@citrix.com>
2016-11-22 17:28:52 +01:00
Dario Faggioli 1d7ecc0348 credit2: fix wrong assert in runq_tickle()
Since b047f888d4 ("xen: sched: leave CPUs doing tasklet
work alone") a cpu executing a tasklet, is not marked as
idle.

Therefore:
 - avoid asserting that we can't find the idle vcpu running
   on one of them, which is not true,
 - avoid triggering a preemption on them (and add an assert
   checking that).

This fixes a bug identified by OSSTest, in flight 102372
(on ARM, but it's not at all ARM specific), where the
ASSERT() was triggering like this:

(XEN) Xen call trace:
(XEN)    [<0022af78>] sched_credit2.c#runq_tickle+0x3e8/0x61c (PC)
(XEN)    [<0022aedc>] sched_credit2.c#runq_tickle+0x34c/0x61c (LR)
(XEN)    [<0022b644>] sched_credit2.c#csched2_context_saved+0x128/0x1a4
(XEN)    [<0023303c>] context_saved+0x7c/0xa4
(XEN)    [<0024f660>] domain.c#schedule_tail+0x2b4/0x308
(XEN)    [<0024faac>] context_switch+0x80/0x94
(XEN)    [<0022ff48>] schedule.c#schedule+0x76c/0x7ec
(XEN)    [<002338d4>] softirq.c#__do_softirq+0xcc/0xec
(XEN)    [<00233968>] do_softirq+0x18/0x28
(XEN)    [<00261084>] leave_hypervisor_tail+0x58/0x88
(XEN)    [<002649d0>] entry.o#return_to_guest+0xc/0xb8
(XEN)
(XEN) ****************************************
(XEN) Panic on CPU 1:
(XEN) Assertion '!is_idle_vcpu(cur->vcpu)' failed at sched_credit2.c:1009
(XEN) ****************************************

Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Release-acked-by: Wei Liu <wei.liu2@citrix.com>
2016-11-22 17:12:50 +01:00
Jan Beulich f6b7fedc89 x86/EFI: meet further spec requirements for runtime calls
So far we didn't guarantee 16-byte alignment of the stack: While (so
far) we don't tell the compiler to use smaller alignment, we also don't
guarantee 16-byte alignment when establishing stack pointers for new
vCPU-s. Runtime service functions using SSE instructions may end with
#GP(0) without that.

Note that making use of -mpreferred-stack-boundary=3, as mentioned in
the comment, wouldn't help to reduce the needed alignment: The compiler
would then be free to align the stack of the function with the aligned
object, but would be permitted to place an odd number of 8-byte objects
there, resulting in the callee to still run on an unaligned stack.

(The only working alternative to the approach chosen here would be to
use -mincoming-stack-boundary=3, but that would affect all functions in
runtime.c, not just the ones actually making runtime services calls.
And it would still require the manual alignment logic here to be used
with gcc 5.2 and earlier - not permitting that command line option -,
just that then the alignment amount would become conditional.)

Hence enforce the needed alignment by making efi_rs_enter() return a
suitably aligned structure, which the caller then necessarily has to
store in a suitably aligned local variable, the address of which then
gets passed to efi_rs_leave(). Also (to limit exposure) move the
function declarations to where they belong: They're local to runtime.c,
and shared only with compat.c (by the latter including the former).

Furthermore we should avoid #MF to be raised on the FLDCW we do.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Wei Liu <wei.liu2@citrix.com>
2016-11-22 13:52:53 +01:00
Ian Jackson 27e14d346e pygrub: Properly quote results, when returning them to the caller:
* When the caller wants sexpr output, use `repr()'
  This is what Xend expects.

  The returned S-expressions are now escaped and quoted by Python,
  generally using '...'.  Previously kernel and ramdisk were unquoted
  and args was quoted with "..." but without proper escaping.  This
  change may break toolstacks which do not properly dequote the
  returned S-expressions.

* When the caller wants "simple" output, crash if the delimiter is
  contained in the returned value.

  With --output-format=simple it does not seem like this could ever
  happen, because the bootloader config parsers all take line-based
  input from the various bootloader config files.

  With --output-format=simple0, this can happen if the bootloader
  config file contains nul bytes.

This is CVE-2016-9379 and CVE-2016-9380 / XSA-198.

Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Tested-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2016-11-22 13:52:09 +01:00
Andrew Cooper 920edccd41 x86/svm: fix injection of software interrupts
The non-NextRip logic in c/s 36ebf14eb "x86/emulate: support for emulating
software event injection" was based on an older version of the AMD software
manual.  The manual was later corrected, following findings from that series.

I took the original wording of "not supported without NextRIP" to mean that
X86_EVENTTYPE_SW_INTERRUPT was not eligible for use.  It turns out that this
is not the case, and the new wording is clearer on the matter.

Despite testing the original patch series on non-NRip hardware, the
swint-emulation XTF test case focuses on the debug vectors; it never ended up
executing an `int $n` instruction for a vector which wasn't also an exception.

During a vmentry, the use of X86_EVENTTYPE_HW_EXCEPTION comes with a vector
check to ensure that it is only used with exception vectors.  Xen's use of
X86_EVENTTYPE_HW_EXCEPTION for `int $n` injection has always been buggy on AMD
hardware.

Fix this by always using X86_EVENTTYPE_SW_INTERRUPT.

Print and decode the eventinj information in svm_vmcb_dump(), as it has
several invalid combinations which cause vmentry failures.

This is CVE-2016-9378 / part of XSA-196.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2016-11-22 13:51:16 +01:00
Andrew Cooper 255e8fe95f x86/emul: correct the IDT entry calculation in inject_swint()
The logic, as introduced in c/s 36ebf14ebe "x86/emulate: support for emulating
software event injection" is buggy.  The size of an IDT entry depends on long
mode being active, not the width of the code segment currently in use.

In particular, this means that a compatibility code segment which hits
emulation for software event injection will end up using an incorrect offset
in the IDT for DPL/Presence checking.  In practice, this only occurs on old
AMD hardware lacking NRip support; all newer AMD hardware, and all Intel
hardware bypass this path in the emulator.

While here, fix a minor issue with reading the IDT entry.  The return value
from ops->read() wasn't checked, but in reality the only failure case is if a
pagefault occurs.  This is not a realistic problem as the kernel will almost
certainly crash with a double fault if this setup actually occured.

This is CVE-2016-9377 / part of XSA-196.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2016-11-22 13:50:49 +01:00
Jan Beulich 1c6c2d60d2 x86emul: fix huge bit offset handling
We must never chop off the high 32 bits.

This is CVE-2016-9383 / XSA-195.

Reported-by: George Dunlap <george.dunlap@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2016-11-22 13:49:06 +01:00
Roger Pau Monné fb08f7d009 libelf: fix stack memory leak when loading 32 bit symbol tables
The 32 bit Elf structs are smaller than the 64 bit ones, which means that
when loading them there's some padding left uninitialized at the end of each
struct (because the size indicated in e_ehsize and e_shentsize is
smaller than the size of elf_ehdr and elf_shdr).

Fix this by introducing a new helper that is used to set
[caller_]xdest_{base/size} and that takes care of performing the appropriate
memset of the region. This newly introduced helper is then used to set and
unset xdest_{base/size} in elf_load_bsdsyms. Now that the full struct
is zeroed, there's no need to specifically zero the undefined section.

This is CVE-2016-9384 / XSA-164.

Suggested-by: Ian Jackson <ian.jackson@eu.citrix.com>
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>

Also remove the open coded (and redundant with the earlier
elf_memset_unchecked()) use of caller_xdest_* from elf_init().

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
2016-11-22 13:48:30 +01:00
Jan Beulich f3fa3abf3e x86/PV: writes of %fs and %gs base MSRs require canonical addresses
Commit c42494acb2 ("x86: fix FS/GS base handling when using the
fsgsbase feature") replaced the use of wrmsr_safe() on these paths
without recognizing that wr{f,g}sbase() use just wrmsrl() and that the
WR{F,G}SBASE instructions also raise #GP for non-canonical input.

Similarly arch_set_info_guest() needs to prevent non-canonical
addresses from getting stored into state later to be loaded by context
switch code. For consistency also check stack pointers and LDT base.
DR0..3, otoh, already get properly checked in set_debugreg() (albeit
we discard the error there).

The SHADOW_GS_BASE check isn't strictly necessary, but I think we
better avoid trying the WRMSR if we know it's going to fail.

This is CVE-2016-9385 / XSA-193.

Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2016-11-22 13:46:28 +01:00
Jan Beulich 93aa42b85a x86/HVM: don't load LDTR with VM86 mode attrs during task switch
Just like TR, LDTR is purely a protected mode facility and hence needs
to be loaded accordingly. Also move its loading to where it
architecurally belongs.

This is CVE-2016-9382 / XSA-192.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Tested-by: Andrew Cooper <andrew.cooper3@citrix.com>
2016-11-22 13:45:44 +01:00
Andrew Cooper 04beafa8e6 x86/hvm: Fix the handling of non-present segments
In 32bit, the data segments may be NULL to indicate that the segment is
ineligible for use.  In both 32bit and 64bit, the LDT selector may be NULL to
indicate that the entire LDT is ineligible for use.  However, nothing in Xen
actually checks for this condition when performing other segmentation
checks.  (Note however that limit and writeability checks are correctly
performed).

Neither Intel nor AMD specify the exact behaviour of loading a NULL segment.
Experimentally, AMD zeroes all attributes but leaves the base and limit
unmodified.  Intel zeroes the base, sets the limit to 0xfffffff and resets the
attributes to just .G and .D/B.

The use of the segment information in the VMCB/VMCS is equivalent to a native
pipeline interacting with the segment cache.  The present bit can therefore
have a subtly different meaning, and it is now cooked to uniformly indicate
whether the segment is usable or not.

GDTR and IDTR don't have access rights like the other segments, but for
consistency, they are treated as being present so no special casing is needed
elsewhere in the segmentation logic.

AMD hardware does not consider the present bit for %cs and %tr, and will
function as if they were present.  They are therefore unconditionally set to
present when reading information from the VMCB, to maintain the new meaning of
usability.

Intel hardware has a separate unusable bit in the VMCS segment attributes.
This bit is inverted and stored in the present field, so the hvm code can work
with architecturally-common state.

This is CVE-2016-9386 / XSA-191.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2016-11-22 13:44:50 +01:00
Andrew Cooper f678e2c781 x86/hvm: Fix non-debug build folling c/s 0745f665a5
The variable is named inst_len, not insn_len.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Release-acked-by: Wei Liu <wei.liu2@citrix.com>
2016-11-21 17:17:51 +00:00
Andrew Cooper 0745f665a5 x86/svm: Fix svm_nextrip_insn_length() when crossing the virtual boundary to 0
vmcb->nextrip can legitimately be less than vmcb->rip when execution wraps
back around to 0.  Instead, complain if the reported length is greater than 15
and use x86_decode_insn() as a fallback.

While making changes here, fix two whitespace issues with the case labels.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Release-acked-by: Wei Liu <wei.liu2@citrix.com>
2016-11-21 14:01:45 +00:00