The maximum size of a message is part of the protocol spec in
xen/include/public/io/xs_wire.h
Before this patch a client which sends an overly large message can
cause a buffer read overrun.
Note if a badly-behaved client sends a very large message
then it will be difficult for them to make their connection
work again-- they will probably need to reboot.
Signed-off-by: David Scott <dave.scott@eu.citrix.com>
Acked-by: Ian Campbell <Ian.Campbell@citrix.com>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>
oxenstored makes use of the OCaml Xenbus bindings, in which the
function xs_ring_read in tools/ocaml/libs/xb/xs_ring_stubs.c is used
to read from the shared memory Xenstore ring.
This function does not correctly handle all possible (prod, cons)
states when MASK_XENSTORE_IDX(prod) > MASK_XENSTORE_IDX(cons).
The root cause is the use of the unmasked values of prod and cons to
calculate to_read. If prod is set to an out-of-range value, the ring
peer can cause to_read to be too large or even negative. This allows
the ring peer to force oxenstored to read and write out of range for
the buffers leading to a crash or possibly to privilege escalation.
Correct this by masking the values of cons and prod at the start, so
we only deal with masked values. This makes the logic simpler, as
semantically inappropriate values of the upper bits of the ring
pointers are simply ignored.
The same vulnerability does not exist in the ring writer because the
only use made of the unmasked value is the check which prevents the
prod pointer overtaking the cons pointer. A ring peer which defeats
this check will suffer only lost data.
However, additionally, precautions need to be taken to ensure that
req_cons and req_prod are only read once in each function. Without
the use of volatile or some asm construct, the compiler can "prove"
that req_cons and req_prod do not change unexpectedly and is permitted
to "amplify" the read of (say) req_cons into two reads at different
times, giving two different values for use as cons, and then use the
two sources of cons interchangeably. (The use of xen_mb() does not
forbid this.)
Therefore do the reads of req_cons and req_prod through a volatile
pointer in both xs_ring_read and xs_ring_write.
This is currently believed to be a theoretical vulnerability as we are
not aware of any compilers which amplify reads in this way.
This is a security issue, part of XSA-38 / CVE-2013-0215.
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Tested-by: Matthew Daley <mattjd@gmail.com>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>
configure checks just for ocamlc, but the tools in tools/ocaml depend
also on ocamlfind. On my workstation I have just ocamlc installed, but
no ocamlfind. As a result make will fail.
Update configure.ac to check also for OCAMLFIND, update various
Makefiles and replace hardcoded ocamlfind string with $(OCAMLFIND)
Please rerun autogen.sh after applying this patch.
Signed-off-by: Olaf Hering <olaf@aepfle.de>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Committed-by: Ian Campbell <ian.campbell@citrix.com>
Changeset 23861:ec7c81fbe0de alters the SBDF encoding expected by the
DOMCTL_{de,}assign_device hypercalls.
While it updates libxl, libxc and the python bindings, the ocaml
bindings got missed. As a result, any attempt to use PCI Passthrough
with Xen-4.2 and later will fail.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Committed-by: Ian Campbell <ian.campbell@citrix.com>
Previously device ids in libxl were treated as integers meaning they
were being initialized to 0, which is a valid device id. This patch
makes devid its own type in libxl and initializes it to -1, an invalid
value.
This fixes a bug where if you try to do a xl DEV-attach multiple
time it will continuously try to reattach device 0 instead of
generating a new device id.
Signed-off-by: Matthew Fioravante <matthew.fioravante@jhuapl.edu>
Reviewed-by: George Dunlap <george.dunlap@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Committed-by: Ian Campbell <ian.campbell@citrix.com>
This does not make the implementation fully asynchronous but just
updates the API to support asynchrony in the future.
Currently although these functions do not call hotplug scripts etc and
therefore are not "slow" (per the comment about ao machinery in
libxl_internal.h) they do interact with the device model and so are
not quite "fast" either. We can live with this for now.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Committed-by: Ian Campbell <ian.campbell@citrix.com>
Split libxl_device_vfb_add into libxl__device_vfb_add (to be used
inside already running ao's), and make libxl_device_vfb_add a stub
to call libxl__device_vfb_add.
Signed-off-by: Roger Pau Monne <roger.pau@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Committed-by: Ian Campbell <ian.campbell@citrix.com>
Split libxl_device_vkb_add into libxl__device_vkb_add (to be used
inside already running ao's), and make libxl_device_vkb_add a stub to
call libxl__device_vkb_add.
Signed-off-by: Roger Pau Monne <roger.pau@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Committed-by: Ian Campbell <ian.campbell@citrix.com>
This patch converts libxl_device_nic_add to an ao operation that
waits for device backend to reach state XenbusStateInitWait and then
marks the operation as completed. This is not really useful now, but
will be used by latter patches that will launch hotplug scripts after
we reached the desired xenbus state.
Calls to libxl_device_nic_add have also been moved to occur after the
device model has been launched, so when hotplug scripts are called
from this functions the interfaces already exists.
As usual, libxl_device_nic_add callers have been modified, and the
internal function libxl__device_disk_add has been used if the call was
inside an already running ao.
Signed-off-by: Roger Pau Monne <roger.pau@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Committed-by: Ian Campbell <ian.campbell@citrix.com>
This patch converts libxl_device_disk_add to an ao operation that
waits for device backend to reach state XenbusStateInitWait and then
marks the operation as completed. This is not really useful now, but
will be used by later patches that will launch hotplug scripts after
we reached the desired xenbus state.
As usual, libxl_device_disk_add callers have been modified, and the
internal function libxl__device_disk_add has been used if the call was
inside an already running ao.
Signed-off-by: Roger Pau Monne <roger.pau@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
[ ijc -- drop hunk modifying libxl_cdrom_insert which is not needed after
25670:3666e9712eaf "libxl: make libxl_cdrom_insert async" ]
Committed-by: Ian Campbell <ian.campbell@citrix.com>
Introduce a new structure to track state of device backends, that will
be used in following patches on this series.
This structure if used for both device creation and device
destruction and removes libxl__ao_device_remove.
Signed-off-by: Roger Pau Monne <roger.pau@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Committed-by: Ian Campbell <ian.campbell@citrix.com>
These renamed a type and the associated functions and the ocaml bindings were
not updated to suit.
This also highlighted that libxl_domain_sched_params should not be DIR_IN since
it is also use as an output struct.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Committed-by: Ian Campbell <ian.campbell@citrix.com>
This type is a but like a "boolean" but with a third state "default" (so really
I suppose it's a tristate).
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
In preparation for introducing a schedule parameter-based structure,
rename libxl_sched_{credit,credit2,sedf} to libxl_sched_{}_domain.
No functional changes.
v2: Wrap long lines while I'm at it
Signed-off-by: George Dunlap <george.dunlap@eu.citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Committed-by: Keir Fraser <keir@xen.org>
send_trigger already included all the operations covered by button_press.
Rework send_trigger to take an enum instead of a string.
I stopped short at removing the xl "button-press" command but instead have
marked it as deprecated.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Committed-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Originally libxltypes.py provided the infrastructure and libxl.idl provided the
specific types.
In 23887:a543e10211f7 libxl.idl became libxl_types.idl (to allow for
libxl_types_internal.idl) which means we now have libxl_types.FOO and
libxltypes.FOO providing different things and annoying people in tab
completion.
Rename the infrastructure as idl.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Committed-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Makes handling of nested structs more correct.
Only change to the generated code right now is that the FOO_Val
(C->ocamlC) function for Enumeration types now takes the C argument by
value instead of reference.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Committed-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Convert libxl_FOO_device_remove, and the function which does the bulk
of the work, libxl__device_remove, to the new async ops scheme.
Adjust all callers.
Also remove libxl__wait_for_device_state which is now obsolete.
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Committed-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Replace the existing API for retrieving high-level events (events
about domains, etc.) from libxl with a new one.
This changes the definition and semantics of the `libxl_event'
structure, and replaces the calls for obtaining information about
domain death and disk eject events.
This is an incompatible change, sorry. The alternative was to try to
provide both the previous horrid API and the new one, and would also
involve never using the name `libxl_event' for the new interface.
The new "libxl_event" structure is blacklisted in the ocaml bindings
for two reasons:
- It has a field name "type" (which is a keyword in ocaml);
the ocaml idl generator should massage this field name on
output, to "type_" perhaps.
- The ocaml idl generator does not support KeyedUnion.
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Committed-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
The changeset
24378:b4365e2c2595 libxl: idl: support new "private" type attribute
is not complete. Actually using this feature does not work because
the ocaml idl generator does not know about it.
So add that support.
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Committed-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
No change to the generated code because this path isn't used yet.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Ian Jackson <ian.jackson.citrix.com>
Committed-by: Ian Jackson <ian.jackson.citrix.com>
Previous an unknown operation would be decoded as a Not_found exception which
would bubble all the way up to the try ... with surrounding the call to
main_loop where it would be logged and ignored.
This would leave the guest hanging waiting for a response to the invalid
request.
Instead introduce a specific "Invalid" operation. Higher level functionality,
such as Process.process_packet, already handles operations which are not
understood with an error reply due to the final wildcard entry in
Process.function_of_type but explicitly handle Invalid this way to make it
clear what is going on.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>
It is unused.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Ian Jackson <ian.jackson.citrix.com>
Committed-by: Ian Jackson <ian.jackson.citrix.com>
Since libxc is re-entrant, there is no need for the OCaml bindings to
prevent more than one thread from entering libxc concurrently.
Previously, the OCaml bindings had prevented re-entrancy by not using
caml_{enter,leave}_blocking_section in the C stubs. The absence of
these calls meant that the global lock remained held during
hypercalls. This caused multi-threaded applications to completely lock
up during long-running hypercalls.
Calls to these functions were present but commented out in the OCaml
bindings some years ago when libxc was not fully re-entrant.
Instead, we now do call caml_{enter,leave}_blocking_section in all the
places it used to be commented out, meaning that the global lock is
released during those hypercalls. We also no longer assert the
XC_OPENFLAG_NON_REENTRANT flag when calling xc_interface_open because
the caller no longer does re-entrancy prevention at those places.
This patch has now gone through a XenRT nightly test; no problems were
observed.
Signed-off-by: Jonathan Davies <jonathan.davies@citrix.com>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>
Currently unused but gives us scope for expansion in an ABI compatible manner
in the future.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Ian Jackson <ian.jackson.citrix.com>
Committed-by: Ian Jackson <ian.jackson.citrix.com>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Ian Jackson <ian.jackson.citrix.com>
Committed-by: Ian Jackson <ian.jackson.citrix.com>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Ian Jackson <ian.jackson.citrix.com>
Committed-by: Ian Jackson <ian.jackson.citrix.com>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Ian Jackson <ian.jackson.citrix.com>
Committed-by: Ian Jackson <ian.jackson.citrix.com>
It has no callers, the only code which adds consoles in internal to libxl and
uses libxl__device_console_add directly.
Rather than worrying about what the public API should look like in this case
simply remove it, adding new APIs is much easier than fixing broken ones...
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Ian Jackson <ian.jackson.citrix.com>
Committed-by: Ian Jackson <ian.jackson.citrix.com>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Ian Jackson <ian.jackson.citrix.com>
Committed-by: Ian Jackson <ian.jackson.citrix.com>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Ian Jackson <ian.jackson.citrix.com>
Committed-by: Ian Jackson <ian.jackson.citrix.com>
Add a new field 'max_nr_cpus' to the physinfo type in the ocaml xc bindings
Signed-off-by: Zheng Li <zheng.li@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell.com>
Committed-by: Ian Jackson <ian.jackson.citrix.com>
The bit bugs are in ocaml vcpu affinity calls, and the off-by-one
error is in the ocaml console ring code
Signed-off-by: Zheng Li <zheng.li@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell.com>
Committed-by: Ian Jackson <ian.jackson.citrix.com>
Acked-by: Jon Ludlam <jonathan.ludlam@eu.citrix.com>
The only user was oxenstored, which has had the relevant bits
merged in.
Signed-off-by: Zheng Li <zheng.li@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell.com>
Committed-by: Ian Jackson <ian.jackson.citrix.com>
Acked-by: Jon Ludlam <jonathan.ludlam@eu.citrix.com>
The library was only minimally used, and was really rather redundant.
Signed-off-by: Zheng Li <zheng.li@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell.com>
Committed-by: Ian Jackson <ian.jackson.citrix.com>
Acked-by: Jon Ludlam <jonathan.ludlam@eu.citrix.com>
ocamlfind does not support namespaces, so to avoid
name clashes the module names have become longer.
Additionally, the xenstore and xenbus subdirs, which
contain several modules each, have been packed into
toplevel Xenstore and Xenbus modules.
xb becomes xenbus, xc becomes xenctrl, xl becomes xenlight,
xs becomes xenstore, eventchn becomes xeneventchn and
mmap becomes xenmmap.
[ Patch modified from that submitted, to update the .hgignore, and to
cope with intervening changes to mmap_stubs.c -iwj ]
Signed-off-by: Jon Ludlam <jonathan.ludlam@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>
Change GET_C_STRUCT to Intf_val to follow the common naming scheme of
OCaml macros, and for better readability.
Signed-off-by: Zheng Li <dev@zheng.li>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>
Fix invalid memory access in OCaml mmap library (to play nicely with the GC)
This was a bug reported by Roberto Di Cosmo. When he tried to reuse
the mmap library for his own project, Mmap.read occasionally got
different result when reading from the same map. This turned out to be
a bug in the binding, where a C pointer was created pointing to a
OCaml value, and the OCaml value was subsequently moved around by the
GC after memory allocation and hence invalidated the C pointer. This
patch removes the indirection of C pointer and uses OCaml macro to
access values directly.
Only Mmap.read function had this problem. The other functions, despite
having the same code style, didn't have memory allocation involved
hence wouldn't intrigue such an error. I've changed all of them to the
safer style for future proof. Directly casting OCaml value's *data
block* (rather than the value itself) as a C pointer is not a common
practice either, but I'll leave it as it is.
The bug hadn't occured on XenServer because XenServer didn't make use
of the Mmap.read function (except in one place for debugging). In
XenServer, most mmap operations were going through another pair of
separately implemented functions (Xs_ring.read/write).
Signed-off-by: Zheng Li <dev@zheng.li>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Committed-by: Ian Jackson <ian.jackson.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
--HG--
rename : tools/libxl/libxl.idl => tools/libxl/libxl_types.idl
Christoph Egger reported than on NetBSD the build fails with
Parsing tools/ocaml/libs/xl/../../../../tools/libxl/libxl.idl
sed: 1: "1i(*\
* AUTO-GENERATED ...": command i expects \ followed by test
gmake[7]: Leaving directory `tools/ocaml/libs/xl'
The following was tested by Christoph on NetBSD and also with GNU-sed
with and without the --posix flag.
In addition when sed fails will still create the output file, which confuses
subsequent make invocations. Generate to a temporary file and move into place
only on success.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Christoph Egger <Christoph.Egger@amd.com>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>
The method by which ocaml converts between ocaml types and C
datastructures is based around explicit matching of field indexes
within the ocaml data type to C structure members which is error prone
to write and fragile to maintain (as evidenced by the difference
between the existing hand coded support and the autogenerated code
which shows how out of date the ocaml bindings have
become). Autogenerating these types should reduce these problems.
There is a short list of types which are blacklisted and not
autogenerated because I expect them to change significantly in the
future due to changes to the IDL type (fixing up the TaggedUnion
class) so I didn't want to spend the time to implement the necessary
autogenerator features just yet..
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Ian Jackson <ian.jackson.citrix.com>
Committed-by: Ian Jackson <ian.jackson.citrix.com>