Commit Graph

4 Commits

Author SHA1 Message Date
Wenwen Wang bd23a72698 virt: vbox: Only copy_from_user the request-header once
In vbg_misc_device_ioctl(), the header of the ioctl argument is copied from
the userspace pointer 'arg' and saved to the kernel object 'hdr'. Then the
'version', 'size_in', and 'size_out' fields of 'hdr' are verified.

Before this commit, after the checks a buffer for the entire request would
be allocated and then all data including the verified header would be
copied from the userspace 'arg' pointer again.

Given that the 'arg' pointer resides in userspace, a malicious userspace
process can race to change the data pointed to by 'arg' between the two
copies. By doing so, the user can bypass the verifications on the ioctl
argument.

This commit fixes this by using the already checked copy of the header
to fill the header part of the allocated buffer and only copying the
remainder of the data from userspace.

Signed-off-by: Wenwen Wang <wang6495@umn.edu>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-14 16:31:59 +02:00
Hans de Goede faf6a2a441 virt: vbox: Use __get_free_pages instead of kmalloc for DMA32 memory
It is not possible to get DMA32 zone memory through kmalloc, causing
the vboxguest driver to malfunction due to getting memory above
4G which the PCI device cannot handle.

This commit changes the kmalloc calls where the 4G limit matters to
using __get_free_pages() fixing vboxguest not working on x86_64 guests
with more then 4G RAM.

Cc: stable@vger.kernel.org
Reported-by: Eloy Coto Pereiro <eloy.coto@gmail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-23 13:41:55 +02:00
Arnd Bergmann 0b598e4f87 virt: vbox: use %pap format for printing resource_size_t
resource_size_t may be larger than pointers depending on configuration,
so we can run into this build warning:

drivers/virt/vboxguest/vboxguest_linux.c: In function 'vbg_pci_probe':
drivers/virt/vboxguest/vboxguest_linux.c:295:4: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
drivers/virt/vboxguest/vboxguest_linux.c:367:4: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]

This uses the special %pap to print the address by reference.

Fixes: 0ba002bc43 ("virt: Add vboxguest driver for Virtual Box Guest integration")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-21 18:06:59 +01:00
Hans de Goede 0ba002bc43 virt: Add vboxguest driver for Virtual Box Guest integration
This commit adds a driver for the Virtual Box Guest PCI device used in
Virtual Box virtual machines. Enabling this driver will add support for
Virtual Box Guest integration features such as copy-and-paste, seamless
mode and OpenGL pass-through.

This driver also offers vboxguest IPC functionality which is needed
for the vboxfs driver which offers folder sharing support.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-18 16:12:22 +01:00