qemu - security update

Several vulnerabilities were discovered in qemu, a fast processor
emulator. The Common Vulnerabilities and Exposures project identifies
the following problems:

• CVE-2016-7909
  Quick Emulator(Qemu) built with the AMD PC-Net II emulator support is
  vulnerable to an infinite loop issue. It could occur while receiving
  packets via pcnet_receive().

A privileged user/process inside guest could use this issue to crash
the Qemu process on the host leading to DoS.

• CVE-2016-8909
  Quick Emulator(Qemu) built with the Intel HDA controller emulation support
  is vulnerable to an infinite loop issue. It could occur while processing the
  DMA buffer stream while doing data transfer in intel_hda_xfer.

A privileged user inside guest could use this flaw to consume excessive CPU
cycles on the host, resulting in DoS.

• CVE-2016-8910
  Quick Emulator(Qemu) built with the RTL8139 ethernet controller emulation
  support is vulnerable to an infinite loop issue. It could occur while
  transmitting packets in C+ mode of operation.

A privileged user inside guest could use this flaw to consume
excessive CPU cycles on the host, resulting in DoS situation.

• CVE-2016-9101
  Quick Emulator(Qemu) built with the i8255x (PRO100) NIC emulation
  support is vulnerable to a memory leakage issue. It could occur while
  unplugging the device, and doing so repeatedly would result in leaking
  host memory affecting, other services on the host.

A privileged user inside guest could use this flaw to cause a DoS on the host
and/or potentially crash the Qemu process on the host.

• CVE-2016-9102 /
  CVE-2016-9105 /
  CVE-2016-9106
  Quick Emulator(Qemu) built with the VirtFS, host directory sharing via
  Plan 9 File System(9pfs) support, is vulnerable to a several memory
  leakage issues.

A privileged user inside guest could use this flaws to leak the host
memory bytes resulting in DoS for other services.

• CVE-2016-9104
  Quick Emulator(Qemu) built with the VirtFS, host directory sharing via
  Plan 9 File System(9pfs) support, is vulnerable to an integer overflow
  issue. It could occur by accessing xattributes values.

A privileged user inside guest could use this flaw to crash the Qemu
process instance resulting in DoS.

• CVE-2016-9103
  Quick Emulator(Qemu) built with the VirtFS, host directory sharing via
  Plan 9 File System(9pfs) support, is vulnerable to an information
  leakage issue. It could occur by accessing xattribute value before
  it’s written to.

A privileged user inside guest could use this flaw to leak host memory
bytes.

For Debian 7 Wheezy, these problems have been fixed in version
1.1.2+dfsg-6+deb7u18.

We recommend that you upgrade your qemu packages.

Further information about Debian LTS security advisories, how to apply
these updates to your system and frequently asked questions can be
found at: <https://wiki.debian.org/LTS&gt;