[Qemu-devel] [V4 PATCH 0/8] virtio-9p: Use chroot to safely access files in passthrough security model

[M. Mohan Kumar]

In passthrough security model, following symbolic links in the server
side could result in TOCTTOU vulnerabilities.

This patchset resolves this issue by creating a dedicated process which
chroots into the share path and all file object access is done in the
chroot environment.

This patchset implements chroot enviroment, provides necessary functions
that can be used by the passthrough function calls.

Changes from version V3
* Return EIO incase of socket read/write fail instead of exiting
* Changed data types as suggested by Blue Swirl
* Chroot process reports error through qemu process when possible

Changes from version V2
* Treat socket IO errors as fatal, ie qemu will exit
* Split patchset based on chroot side (server) and qemu side(client)
  functionalities

M. Mohan Kumar (8):
  Implement qemu_read_full
  Provide chroot environment server side interfaces
  Add client side interfaces for chroot environment
  Add support to open a file in chroot environment
  Create support in chroot environment
  Support for creating special files
  Move file post creation changes to none security model
  Chroot environment for other functions

 Makefile.objs              |    1 +
 hw/9pfs/virtio-9p-chroot.c |  463 ++++++++++++++++++++++++++++++++++++++++++++
 hw/9pfs/virtio-9p-chroot.h |   44 +++++
 hw/9pfs/virtio-9p-local.c  |  455 +++++++++++++++++++++++++++++++++++--------
 hw/9pfs/virtio-9p.c        |   33 +++
 hw/file-op-9p.h            |    3 +
 osdep.c                    |   32 +++
 qemu-common.h              |    2 +
 8 files changed, 953 insertions(+), 80 deletions(-)
 create mode 100644 hw/9pfs/virtio-9p-chroot.c
 create mode 100644 hw/9pfs/virtio-9p-chroot.h

-- 
1.7.3.4