These functions take guest pfns and look them up in the p2m. They did
no range checking.
However, some callers, notably xc_dom_boot.c:setup_hypercall_page want
to pass untrusted guest-supplied value(s). It is most convenient to
detect this here and return INVALID_MFN.
This is part of the fix to a security issue, XSA-55.
Changes from Xen 4.2 version of this patch:
* 4.2 lacks dom->rambase_pfn, so don't add/subtract/check it.
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
A sufficiently malformed input to libxc (such as a malformed input ELF
or other guest-controlled data) might cause one of libxc's malloc() to
fail. In this case we need to make sure we don't dereference or do
pointer arithmetic on the result.
Search for all occurrences of \b(m|c|re)alloc in libxc, and all
functions which call them, and add appropriate error checking where
missing.
This includes the functions xc_dom_malloc*, which now print a message
when they fail so that callers don't have to do so.
The function xc_cpuid_to_str wasn't provided with a sane return value
and has a pretty strange API, which now becomes a little stranger.
There are no in-tree callers.
Changes in the Xen 4.2 version of this series:
* No need to fix code relating to ARM.
* No need to fix code relating to superpage support.
* Additionally fix `dom->p2m_host = xc_dom_malloc...' in xc_dom_ia64.c.
Changes in the Xen 4.1 version of this series:
* An additional check is needed in xc_flask.c:xc_flask_access.
This is part of the fix to a security issue, XSA-55.
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
The return values from xc_dom_*_to_ptr and xc_map_foreign_range are
sometimes dereferenced, or subjected to pointer arithmetic, without
checking whether the relevant function failed and returned NULL.
Add an appropriate error check at every call site.
Changes in the 4.2 backport of this series:
* Fix tools/libxc/xc_dom_x86.c:setup_pgtables_x86_32.
* Fix tools/libxc/xc_dom_ia64.c:start_info_ia64.
* Fix tools/libxc/ia64/xc_ia64_dom_fwloader.c:xc_dom_load_fw_kernel.
Conflicts in the 4.1 backport of this series:
* xc_dom_load_elf_kernel has less error handling in 4.1.
* the VM generation ID code is not in 4.1.
This is part of the fix to a security issue, XSA-55.
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
This is a simple binary image loader with its own metadata format.
However, it is too careless with image-supplied values.
Add the following checks:
* That the image is bigger than the metadata table; otherwise the
pointer arithmetic to calculate the metadata table location may
yield undefined and dangerous values.
* When clamping the end of the region to search, that we do not
calculate pointers beyond the end of the image. The C
specification does not permit this and compilers are becoming ever
more determined to miscompile code when they can "prove" various
falsehoods based on assertions from the C spec.
* That the supplied image is big enough for the text we are allegedly
copying from it. Otherwise we might have a read overrun and copy
the results (perhaps a lot of secret data) into the guest.
This is part of the fix to a security issue, XSA-55.
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Abolish ELF_PTRVAL_[CONST_]{CHAR,VOID}; change uses to elf_ptrval.
Abolish ELF_HANDLE_DECL_NONCONST; change uses to ELF_HANDLE_DECL.
Abolish ELF_OBSOLETE_VOIDP_CAST; simply remove all uses.
No functional change. (Verified by diffing assembler output.)
This is part of the fix to a security issue, XSA-55.
Conflicts in the 4.1 backport:
* elf_load_image is not in 4.1.
* elf_note_numeric_array is not in 4.1.
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Ensure that libelf does not have any loops which can run away
indefinitely even if the input is bogus. (Grepped for \bfor, \bwhile
and \bgoto in libelf and xc_dom_*loader*.c.)
Changes needed:
* elf_note_next uses the note's unchecked alleged length, which might
wrap round. If it does, return ELF_MAX_PTRVAL (0xfff..fff) instead,
which will be beyond the end of the section and so terminate the
caller's loop.
* In various loops over section and program headers, check that the
calculated header pointer is still within the image, and quit the
loop if it isn't.
We have not changed loops which might, in principle, iterate over the
whole image - even if they might do so one byte at a time with a
nontrivial access check function in the middle.
This is part of the fix to a security issue, XSA-55.
Conflicts in Xen 4.1 version of the series:
* Trivial conflict due to elf_note_numeric_array not existing.
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Copy the one file tools/libxc/xc_bitops.h from xen.git#aa1355f9.
We will need this for the next patch, which calls for a bitmap in
libxc.
xc_bitops.h was introduced to unify various existing sets of bitmap
operations. In this patch we backport only the introduction, not the
replacement of the other instances. So we introduce another instance
Sorry :-/.
This is part of the fix to a security issue, XSA-55.
This patch is unique to the Xen 4.1 version of the XSA-55 series.
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Signed integers have undesirable undefined behaviours on overflow.
Malicious compilers can turn apparently-correct code into code with
security vulnerabilities etc.
So use only unsigned integers. Exceptions are booleans (which we have
already changed) and error codes.
We _do_ change all the chars which aren't fixed constants from our own
text segment, but not the char*s. This is because it is safe to
access an arbitrary byte through a char*, but not necessarily safe to
convert an arbitrary value to a char.
As a consequence we need to compile libelf with -Wno-pointer-sign.
It is OK to change all the signed integers to unsigned because all the
inequalities in libelf are in contexts where we don't "expect"
negative numbers.
In libelf-dominfo.c:elf_xen_parse we rename a variable "rc" to
"more_notes" as it actually contains a note count derived from the
input image. The "error" return value from elf_xen_parse_notes is
changed from -1 to ~0U.
grepping shows only one occurrence of "PRId" or "%d" or "%ld" in
libelf and xc_dom_elfloader.c (a "%d" which becomes "%u").
This is part of the fix to a security issue, XSA-55.
Conflicts in 4.1 series:
* xc_dom_load_elf_kernel has no rc variable to change.
* elf_load_image doesn't exist.
For those concerned about unintentional functional changes, the
following rune produces a version of the patch which is much smaller
and eliminates only non-functional changes:
GIT_EXTERNAL_DIFF=.../unsigned-differ git-diff <before>..<after>
where <before> and <after> are git refs for the code before and after
this patch, and unsigned-differ is this shell script:
#!/bin/bash
set -e
seddery () {
perl -pe 's/\b(?:elf_errorstatus|elf_negerrnoval)\b/int/g'
}
path="$1"
in="$2"
out="$5"
set +e
diff -pu --label "$path~" <(seddery <"$in") --label "$path" <(seddery <"$out")
rc=$?
set -e
if [ $rc = 1 ]; then rc=0; fi
exit $rc
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
We want to remove uses of "int" because signed integers have
undesirable undefined behaviours on overflow. Malicious compilers can
turn apparently-correct code into code with security vulnerabilities
etc.
In this patch we change all the booleans in libelf to C99 bool,
from <stdbool.h>.
For the one visible libelf boolean in libxc's public interface we
retain the use of int to avoid changing the ABI; libxc converts it to
a bool for consumption by libelf.
It is OK to change all values only ever used as booleans to _Bool
(bool) because conversion from any scalar type to a _Bool works the
same as the boolean test in if() or ?: and is always defined (C99
6.3.1.2). But we do need to check that all these variables really are
only ever used that way. (It is theoretically possible that the old
code truncated some 64-bit values to 32-bit ints which might become
zero depending on the value, which would mean a behavioural change in
this patch, but it seems implausible that treating 0x????????00000000
as false could have been intended.)
This is part of the fix to a security issue, XSA-55.
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
This arranges that if the new pointer reference error checking
tripped, we actually get a message about it. In this patch these
messages do not change the actual return values from the various
functions: so pointer reference errors do not prevent loading. This
is for fear that some existing kernels might cause the code to make
these wild references, which would then break, which is not a good
thing in a security patch.
In xen/arch/x86/domain_build.c we have to introduce an "out" label and
change all of the "return rc" beyond the relevant point into "goto
out".
This is part of the fix to a security issue, XSA-55.
Differences in 4.1 backport:
* No xen/arch/arm.
* There was less error handling in xen/arch/x86/domain_build.c
so less need to change it.
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
elf_is_elfbinary didn't take a length parameter and could potentially
access out of range when provided with a very short image.
We only need to check the size is enough for the actual dereference in
elf_is_elfbinary; callers are just using it to check the magic number
and do their own checks (usually via the new elf_ptrval system) before
dereferencing other parts of the header.
This is part of the fix to a security issue, XSA-55.
Conflicts in 4.1 backport:
* xen/arch/x86/bzimage.c in 4.1 doesn't use elf_is_elfbinary.
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
We change the ELF_PTRVAL and ELF_HANDLE types and associated macros:
* PTRVAL becomes a uintptr_t, for which we provide a typedef
elf_ptrval. This means no arithmetic done on it can overflow so
the compiler cannot do any malicious invalid pointer arithmetic
"optimisations". It also means that any places where we
dereference one of these pointers without using the appropriate
macros or functions become a compilation error.
So we can be sure that we won't miss any memory accesses.
All the PTRVAL variables were previously void* or char*, so
the actual address calculations are unchanged.
* ELF_HANDLE becomes a union, one half of which keeps the pointer
value and the other half of which is just there to record the
type.
The new type is not a pointer type so there can be no address
calculations on it whose meaning would change. Every assignment or
access has to go through one of our macros.
* The distinction between const and non-const pointers and char*s
and void*s in libelf goes away. This was not important (and
anyway libelf tended to cast away const in various places).
* The fields elf->image and elf->dest are renamed. That proves
that we haven't missed any unchecked uses of these actual
pointer values.
* The caller may fill in elf->caller_xdest_base and _size to
specify another range of memory which is safe for libelf to
access, besides the input and output images.
* When accesses fail due to being out of range, we mark the elf
"broken". This will be checked and used for diagnostics in
a following patch.
We do not check for write accesses to the input image. This is
because libelf actually does this in a number of places. So we
simply permit that.
* Each caller of libelf which used to set dest now sets
dest_base and dest_size.
* In xc_dom_load_elf_symtab we provide a new actual-pointer
value hdr_ptr which we get from mapping the guest's kernel
area and use (checking carefully) as the caller_xdest area.
* The STAR(h) macro in libelf-dominfo.c now uses elf_access_unsigned.
* elf-init uses the new elf_uval_3264 accessor to access the 32-bit
fields, rather than an unchecked field access (ie, unchecked
pointer access).
* elf_uval has been reworked to use elf_uval_3264. Both of these
macros are essentially new in this patch (although they are derived
from the old elf_uval) and need careful review.
* ELF_ADVANCE_DEST is now safe in the sense that you can use it to
chop parts off the front of the dest area but if you chop more than
is available, the dest area is simply set to be empty, preventing
future accesses.
* We introduce some #defines for memcpy, memset, memmove and strcpy:
- We provide elf_memcpy_safe and elf_memset_safe which take
PTRVALs and do checking on the supplied pointers.
- Users inside libelf must all be changed to either
elf_mem*_unchecked (which are just like mem*), or
elf_mem*_safe (which take PTRVALs) and are checked. Any
unchanged call sites become compilation errors.
* We do _not_ at this time fix elf_access_unsigned so that it doesn't
make unaligned accesses. We hope that unaligned accesses are OK on
every supported architecture. But it does check the supplied
pointer for validity.
This is part of the fix to a security issue, XSA-55.
Additional change in 4.1 backport:
* ELF_PRPTRVAL needs to be defined oddly on 4.1 and earlier because
Xen's headers provide no definitions of uintptr_t or PRIuPTR.
Conflicts:
* Callers of elf_load_binary don't check its return value in 4.1.
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
It is not safe to simply take pointers into the ELF and use them as C
pointers. They might not be properly nul-terminated (and the pointers
might be wild).
So we are going to introduce a new function elf_strval for safely
getting strings. This will check that the addresses are in range and
that there is a proper nul-terminated string. Of course it might
discover that there isn't. In that case, it will be made to fail.
This means that elf_note_name might fail, too.
For the benefit of call sites which are just going to pass the value
to a printf-like function, we provide elf_strfmt which returns
"(invalid)" on failure rather than NULL.
In this patch we introduce dummy definitions of these functions. We
introduce calls to elf_strval and elf_strfmt everywhere, and update
all the call sites with appropriate error checking.
There is not yet any semantic change, since before this patch all the
places where we introduce elf_strval dereferenced the value anyway, so
it mustn't have been NULL.
In future patches, when elf_strval is made able return NULL, when it
does so it will mark the elf "broken" so that an appropriate
diagnostic can be printed.
This is part of the fix to a security issue, XSA-55.
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Use the new PTRVAL macros and elf_access_unsigned in
print_l1_mfn_valid_note.
No functional change unless the input is wrong, or we are reading a
file for a different endianness.
Separated out from the previous patch because this change does produce
a difference in the generated code.
This is part of the fix to a security issue, XSA-55.
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
We introduce a collection of macros which abstract away all the
pointer arithmetic and dereferences used for accessing the input ELF
and the output area(s). We use the new macros everywhere.
For now, these macros are semantically identical to the code they
replace, so this patch has no functional change.
elf_is_elfbinary is an exception: since it doesn't take an elf*, we
need to handle it differently. In a future patch we will change it to
take, and check, a length parameter. For now we just mark it with a
fixme.
Nontrivial differences in the 4.1 backport:
* We need to provide our own elf_uintptr_t since Xen doesn't.
* We see some additional differences in our verification diff.
* The "function-filter" needs to massage additional symbol names.
Conflicts:
* In xc_dom_load_elf_symtab the old code used
*(Elf64_Word*)(&shdr->e64.sh_name) and the new Elf32_Word
but in fact the type in the struct has changed too so the
new code using elf_store_field is still correct.
* loadelfimage, elf_load_image etc. don't exist and are done
directly with memcpy/memset; patch adjusted appropriately.
* elf_note_numeric_array doesn't exist in 4.1.
That this patch has no functional change can be verified as follows:
0. Copy the scripts "comparison-generate" and "function-filter"
out of this commit message.
1. Check out the tree before this patch.
2. Run the script ../comparison-generate .... ../before
3. Check out the tree after this patch.
4. Run the script ../comparison-generate .... ../after
5. diff --exclude=\*.[soi] -ruN before/ after/ |less
Expect these differences:
* stubdom/zlib-x86_64/ztest*.s2
The filename of this test file apparently contains the pid.
* stubdom/grub/kexec.s2:
Large differences following ".section .debug_info" (which
the 4.1 build system erroneously fails to suppress).
* tools/libxc/xc_domain_restore.s2 (64-bit build):
One trivial code gen difference with no semantic import.
* xen/common/version.s2
The xen build timestamp appears in two diff hunks.
Verification that this is all that's needed:
In a completely built xen.git,
find * -name .*.d -type f | xargs grep -l libelf\.h
Expect results in:
xen/arch/x86: Checked above.
tools/libxc: Checked above.
tools/xcutils/readnotes: Checked above.
tools/xenstore: Checked above.
xen/common/libelf:
This is the build for the hypervisor; checked in B above.
stubdom:
We have one stubdom which reads ELFs using our libelf,
pvgrub, which is checked above.
I have not done this verification for ARM.
This is part of the fix to a security issue, XSA-55.
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
-8<- comparison-generate -8<-
#!/bin/bash
# usage:
# cd xen.git
# .../comparison-generate OUR-CONFIG BUILD-RUNE-PREFIX ../before|../after
# eg:
# .../comparison-generate ~/work/.config 'schroot -pc64 --' ../before
set -ex
test $# = 3 || need-exactly-three-arguments
our_config=$1
build_rune_prefix=$2
result_dir=$3
git clean -x -d -f
cp "$our_config" .
cat <<END >>.config
debug_symbols=n
CFLAGS += -save-temps
END
perl -i~ -pe 's/ -g / -g0 / if m/^CFLAGS/' xen/Rules.mk
if [ -f ./configure ]; then
$build_rune_prefix ./configure
fi
$build_rune_prefix make -C xen
$build_rune_prefix make -C tools/include
$build_rune_prefix make -C stubdom grub
$build_rune_prefix make -C tools/libxc
$build_rune_prefix make -C tools/xenstore
$build_rune_prefix make -C tools/xcutils
rm -rf "$result_dir"
mkdir "$result_dir"
set +x
for f in `find xen tools stubdom -name \*.[soi]`; do
mkdir -p "$result_dir"/`dirname $f`
cp $f "$result_dir"/${f}
case $f in
*.s)
../function-filter <$f >"$result_dir"/${f}2
;;
esac
done
echo ok.
-8<-
-8<- function-filter -8<-
#!/usr/bin/perl -w
# function-filter
# script for massaging gcc-generated labels to be consistent
use strict;
our @lines;
my $sedderybody = "sub seddery () {\n";
while (<>) {
push @lines, $_;
if (m/^(__FUNCTION__|__func__|_ctx|note_desc|types|last_order|memflags|mutex|d\d_cpu_last|write_count|wall_last|__PRETTY_FUNCTION__)\.(\d+)\:/ ||
m/^\s+\.local\s+(_ctx|write_count|d\d_cpu_last|wall_last|mutex)\.(\d+)\s*$/) {
$sedderybody .= " s/\\b$1\\.$2\\b/__XSA55MANGLED__$1.$./g;\n";
}
}
$sedderybody .= "}\n1;\n";
eval $sedderybody or die $@;
foreach (@lines) {
seddery();
print or die $!;
}
-8<-
xc_dom_load_elf_symtab (with load==0) calls elf_round_up, but it
mistakenly used the uninitialised variable "syms" when calculating
dom->bsd_symtab_start. This should be a reference to "elf".
This change might have the effect of rounding the value differently.
Previously if the uninitialised value (a single byte on the stack) was
ELFCLASS64 (ie, 2), the alignment would be to 8 bytes, otherwise to 4.
However, the value is calculated from dom->kernel_seg.vend so this
could only make a difference if that value wasn't already aligned to 8
bytes.
This is part of the fix to a security issue, XSA-55.
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
* Ensure that xc_dom_pfn_to_ptr (when called with count==0) does not
return a previously-allocated block which is entirely before the
requested pfn (!)
* Provide a version of xc_dom_pfn_to_ptr, xc_dom_pfn_to_ptr_retcount,
which provides the length of the mapped region via an out parameter.
* Change xc_dom_vaddr_to_ptr to always provide the length of the
mapped region and change the call site in xc_dom_binloader.c to
check it. The call site in xc_dom_load_elf_symtab will be corrected
in a forthcoming patch, and for now ignores the returned length.
This is part of the fix to a security issue, XSA-55.
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
v5: This patch is new in v5 of the series.
Provide a version of xc_dom_seg_to_ptr which returns the number of
guest pages it has actually mapped. This is useful for callers who
want to do range checking; we will use this later in this series.
This is part of the fix to a security issue, XSA-55.
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
This file is not actually used. It's not built in Xen's instance of
libelf; in libxc's it's built but nothing in it is called. Do not
compile it in libxc, and delete it.
This reduces the amount of work we need to do in forthcoming patches
to libelf (particularly since as libelf-relocate.c is not used it is
probably full of bugs).
This is part of the fix to a security issue, XSA-55.
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
This reverts commit 22de18bb89.
The code this patch added is redundant with already present code in
set_iommu_{command_buffer,event_log}_control().
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
master commit: e430510e5c
master date: 2013-06-05 10:05:49 +0200
Other than the HVM emulation path, the PV case so far failed to check
that YMM state requires SSE state to be enabled, allowing for a #GP to
occur upon passing the inputs to XSETBV inside the hypervisor.
This is CVE-2013-2078 / XSA-54.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
master commit: 365c95f7de
master date: 2013-06-04 09:29:07 +0200
Just like FXRSTOR, XRSTOR can raise #GP if bad content is being passed
to it in the memory block (i.e. aspects not under the control of the
hypervisor, other than e.g. proper alignment of the block).
Also correct the comment explaining why FXRSTOR needs exception
recovery code to not wrongly state that this can only be a result of
the control tools passing a bad image.
This is CVE-2013-2077 / XSA-53.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
master commit: c6ae65db36
master date: 2013-06-04 09:27:58 +0200
Just like for FXSAVE/FXRSTOR, XSAVE/XRSTOR also don't save/restore the
last instruction and operand pointers as well as the last opcode if
there's no pending unmasked exception (see CVE-2006-1056 and commit
9747:4d667a139318).
While the FXSR solution sits in the save path, I prefer to have this in
the restore path because there the handling is simpler (namely in the
context of the pending changes to properly save the selector values for
32-bit guest code).
Also this is using FFREE instead of EMMS, as it doesn't seem unlikely
that in the future we may see CPUs with x87 and SSE/AVX but no MMX
support. The goal here anyway is just to avoid an FPU stack overflow.
I would have preferred to use FFREEP instead of FFREE (freeing two
stack slots at once), but AMD doesn't document that instruction.
This is CVE-2013-2076 / XSA-52.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Tested-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
master commit: 8dcf9f0113
master date: 2013-06-04 09:26:54 +0200
When support for pinning more than 64 cpus was added, check for cpu
out-of-range values was removed. This can lead to subsequent
out-of-bounds cpumap array accesses in case the cpu number is higher
than the actual count.
This patch returns the check.
This is CVE-2013-2072 / XSA-56
Signed-off-by: Petr Matousek <pmatouse@redhat.com>
master commit: 41abbadef6
master date: 2013-05-29 15:49:22 +0100
current_cpu_data becomes valid only relatively late in the boot
process, so looking there for a particular feature early in the game
would generally give the appearance of the feature being unavailable.
Getting this wrong means that at kexec time the system would get
returned to xAPIC mode, causing disconnect_bsp_APIC() to try to access
the APIC page, which on systems with x2APIC pre-enabled will never get
set up.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Keir Fraser <keir@xen.org>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 234c4dde2f
master date: 2013-05-23 13:08:32 +0200
There is a small set of places where files in subdirectories get
compiled from the parent directory. Dependency file wise this is no
problem as long as the files use names distinct without regard to the
directories they sit in, and tools/console/ violates this (in having
two main.c files). Hence we need to avoid losing the directory name,
both to ensure the two compiler instances don't simultaneously write
to the same file (happening of which is what triggered me looking
into this) and to guarantee dependencies for all files will be seen
by make on an incremental rebuild.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
master commit: 4d788e164d
master date: 2013-05-21 10:16:30 +0200
Reference at time of patch:
http://support.amd.com/us/ChipsetMotherboard_TechDocs/46303.pdf
Erratum 64 states that the head and tail pointers for the Command buffer and
Event log are only reset on a cold boot, not a warm boot.
While the erratum is limited to systems using SR56xx chipsets (such as Family
10h CPUs), resetting the pointers is a sensible action in all cases, including
the PPR log for consistency.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Keir Fraser <keir@xen.org>
Acked-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
master commit: 6d243308e1
master date: 2013-05-22 15:26:52 +0200
The hypervisor side changes for XSA-46 require the tool stack to now
always map the guest pIRQ before granting access permission to the
underlying host IRQ (GSI). This in particular requires that pciif.py
no longer can skip this step (assuming qemu would do it) for HVM
guests.
This in turn exposes, however, an inconsistency between xend and qemu:
The former wants to always establish 1:1 mappings between pIRQ and host
IRQ (for non-MSI only of course), while the latter always wants to
allocate an arbitrary mapping. Since the whole tool stack obviously
should always agree on the mapping model, make libxc enforce the 1:1
mapping as the more natural one (as well as being the one that allows
for easier debugging, since there no need to find out the extra
mapping). Users of libxc that want to establish a particular (rather
than an allocated) mapping are still free to do so, as well as tool
stacks not based on libxc wanting to implement an allocation based
model (which is why it's not the hypervisor that's being changed to
enforce either model).
Since libxl, like xend, already uses a 1:1 model, it's unaffected by
the libxc change (and it being unaffected by the original hypervisor
side changes is - afaict - simply due to qemu getting spawned at a
later point in time compared to the xend event flow).
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Tested-by: Andreas Falck <falck.andreas.lists@gmail.com> (on 4.1)
Tested-by: Gordan Bobic <gordan@bobich.net> (on 4.2)
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 934a5253d9
master date: 2013-05-21 11:32:34 +0200
iomem_access_permitted() wants an inclusive range as input.
Also use pfn_to_paddr() in nearby code instead of open coding it.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Tim Deegan <tim@xen.org>
master commit: afa65ddfd8
master date: 2013-05-15 14:34:05 +0200
This fixes two regressions from c/s 20143:a7de5bd776ca ("x86: Make the
hypercall PHYSDEVOP_alloc_irq_vector hypercall dummy"):
For one, IRQs that had their vector set up by Xen internally without a
handler ever having got set (e.g. via "com<n>=..." without a matching
consumer option like "console=com<n>") would wrongly call
add_pin_to_irq() here, triggering the BUG_ON() in that function.
Second, when assign_irq_vector() fails this addition to irq_2_pin[]
needs to be undone.
In the context of this I'm also surprised that the irq_2_pin[]
manipulations here occur without any lock, i.e. rely on Dom0 to do
some sort of serialization.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Keir Fraser <keir@xen.org>
master commit: 30256a0ff1
master date: 2013-05-15 10:52:02 +0200
This drops the "preemptible" parameters from various functions where
now they can't (or shouldn't, validated by assertions) be run in non-
preemptible mode anymore, to prove that manipulations of at least L3
and L4 page tables and page table entries are now always preemptible,
i.e. the earlier patches actually fulfill their purpose of fixing the
resulting security issue.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Tim Deegan <tim@xen.org>
master commit: b965b31a6b
master date: 2013-05-02 17:04:14 +0200
Only in cases where we don't know what to do we should leave the IRTE
blank (suppressing all validation), but we should always log a warning
in those cases (as being insecure).
This is CVE-2013-1952 / XSA-49.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: "Zhang, Xiantao" <xiantao.zhang@intel.com>
master commit: 63cec00679
master date: 2013-05-02 17:08:58 +0200
... as they may take significant amounts of time.
This requires cloning the tweaked continuation logic from
do_mmuext_op() to do_mmu_update().
Note that in mod_l[34]_entry() a negative "preemptible" value gets
passed to put_page_from_l[34]e() now, telling the callee to store the
respective page in current->arch.old_guest_table (for a hypercall
continuation to pick up), rather than carrying out the put right away.
This is going to be made a little more explicit by a subsequent cleanup
patch.
This is part of CVE-2013-1918 / XSA-45.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Tim Deegan <tim@xen.org>
master commit: b8efae696c
master date: 2013-05-02 16:39:37 +0200
... as it may take significant amounts of time.
Since we can't re-invoke the operation in a second attempt, the
continuation logic must be slightly tweaked so that we make sure
do_mmuext_op() gets run one more time even when the preempted unpin
operation was the last one in a batch.
This is part of CVE-2013-1918 / XSA-45.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Tim Deegan <tim@xen.org>
master commit: a3e049f8e8
master date: 2013-05-02 16:39:06 +0200
.. as the root page table validation (and the dropping of an eventual
old one) can require meaningful amounts of time.
This is part of CVE-2013-1918 / XSA-45.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Tim Deegan <tim@xen.org>
master commit: 99d2b14991
master date: 2013-05-02 16:38:30 +0200
... as dropping the old page tables may take significant amounts of
time.
This is part of CVE-2013-1918 / XSA-45.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Tim Deegan <tim@xen.org>
master commit: 4939f9a6de
master date: 2013-05-02 16:37:24 +0200
... as it may take significant amounts of time.
This is part of CVE-2013-1918 / XSA-45.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Tim Deegan <tim@xen.org>
master commit: 918a5f17b4
master date: 2013-05-02 16:36:44 +0200
... as it may take significant amounts of time.
This is part of CVE-2013-1918 / XSA-45.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Tim Deegan <tim@xen.org>
master commit: e2e6b7b627
master date: 2013-05-02 16:35:50 +0200
... as it may take significant amounts of time.
The function, being moved to mm.c as the better home for it anyway, and
to avoid having to make a new helper function there non-static, is
given a "preemptible" parameter temporarily (until, in a subsequent
patch, its other caller is also being made capable of dealing with
preemption).
This is part of CVE-2013-1918 / XSA-45.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Tim Deegan <tim@xen.org>
master commit: 6cdc9be2a5
master date: 2013-05-02 16:34:21 +0200
When acquiring a transitive grant for copy then the owning domain
needs to be locked down as well as the granting domain. This was being
done, but the unlocking was not. The acquire code now stores the
struct domain * of the owning domain (rather than the domid) in the
active entry in the granting domain. The release code then does the
unlock on the owning domain. Note that I believe I also fixed a bug
where, for non-transitive grants the active entry contained a
reference to the acquiring domain rather than the granting
domain. From my reading of the code this would stop the release code
for transitive grants from terminating its recursion correctly.
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
master commit: f544bf377e
master date: 2011-03-08 16:30:30 +0000
Also, for non-transitive grants we now avoid incorrectly recursing
in __release_grant_for_copy.
This is CVE-2013-1964 / XSA-50.
Reported-by: Manuel Bouyer <bouyer@antioche.eu.org>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Tested-by: Manuel Bouyer <bouyer@antioche.eu.org>
- properly revoke IRQ access in map_domain_pirq() error path
- don't permit replacing an in use IRQ
- don't accept inputs in the GSI range for MAP_PIRQ_TYPE_MSI
- track IRQ access permission in host IRQ terms, not guest IRQ ones
(and with that, also disallow Dom0 access to IRQ0)
This is CVE-2013-1919 / XSA-46.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
master commit: 545607eb3c
master date: 2013-04-18 16:11:23 +0200
... as it causes problems if we happen to exit back via IRET: In the
course of trying to handle the fault, the hypervisor creates a stack
frame by hand, and uses PUSHFQ to set the respective EFLAGS field, but
expects to be able to IRET through that stack frame to the second
portion of the fixup code (which causes a #GP due to the stored EFLAGS
having NT set).
And even if this worked (e.g if we cleared NT in that path), it would
then (through the fail safe callback) cause a #GP in the guest with the
SYSENTER handler's first instruction as the source, which in turn would
allow guest user mode code to crash the guest kernel.
Inject a #GP on the fake (NULL) address of the SYSENTER instruction
instead, just like in the case where the guest kernel didn't register
a corresponding entry point.
On 32-bit we also need to make sure we clear SYSENTER_CS for all CPUs
(neither #RESET nor #INIT guarantee this).
This is CVE-2013-1917 / XSA-44.
Reported-by: Andrew Cooper <andrew.cooper3@citirx.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Tested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: fdac951560
master date: 2013-04-18 16:00:35 +0200
This fixes a regression side-effect caused by:
IOMMU: properly check whether interrupt remapping is enabled
git: fae0372140
hg: 26742:e1ec14bad0cb
On the crash path in nmi_shootdown_cpus(), we shut down the IOMMU, then
disable the IOAPIC.
On systems which support interrupt remapping, the variable iommu_intremap
remains set, meaning that disable_IO_APIC() issues interrupt remapping
invalidate requests.
IOAPIC interrupt remapping used to be conditional on iommu_enabled, but is now
conditional on iommu_intremap, following the above changeset.
This behaviour can be fixed by also indicating that interrupt remapping is not
enabled after shutting down the IOMMU.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 53fd1d8458
master date: 2013-04-16 10:34:32 +0200
scale_delta(), which is being called by that function, doesn't cope
with that.
Also print a warning message, so hopefully we can eventually figure why
occasionally a negative value results from the calculation in the first
place.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Keir Fraser <keir@xen.org>
master commit: eb60be3dd8
master date: 2013-04-11 12:07:55 +0200
Matthew Daley
Ian Jackson
Jan Beulich
Petr Matousek
Andrew Cooper
Paul Durrant