[Qemu-devel] [PATCH 0/2] object_initialize: check size of passed in memory

[Peter Maydell <peter.maydell@linaro.org>]

This patchset addresses a concern that came up with Andreas' recent
patches for using embedded objects in some of the ARM CPU devices:
object_initialize() doesn't check that there's actually enough space
for the type being added, so if you have:

struct MyDevice {
   ...
   SomeObject obj;
};

    object_initialize(&mydev->obj, "some-object");

then there's no compile time or runtime check that SomeObject
is really big enough for the "some-object" object -- if the
implementation is changed later then there will be silent
memory corruption.

These patches make object_initialize() a macro which can then
use sizeof(*PTR) to pass the size into the implementation to
be checked.

The virtio patch is worth applying anyway -- it removes some
pointless casts which would otherwise have caused false
positives.

Disclaimer: I've eyeballed all the uses of object_initialize()
but I haven't necessarily tested them all.

Peter Maydell (2):
  virtio: Remove unnecessary OBJECT casts
  qom: Make object_initialize and object_initialize_with_type check
    size

 hw/core/qdev.c             |    2 +-
 hw/s390x/s390-virtio-bus.c |   12 ++++++------
 hw/s390x/virtio-ccw.c      |   14 +++++++-------
 hw/virtio/virtio-pci.c     |   16 ++++++++--------
 include/qom/object.h       |   36 ++++++++++++++++++++++++++++++++++--
 qom/object.c               |    9 +++++----
 6 files changed, 61 insertions(+), 28 deletions(-)

-- 
1.7.9.5