[Secure-testing-team] Bug#809230: CVE-2015-8558: usb: infinite loop in ehci_advance_state results in DoS

[Michael Tokarev]

Source: qemu
Version: 0.14+dfsg-1
Severity: important
Tags: security patch upstream fixed-upstream pending

CVE-2015-8558 has been reported against qemu usb ehci emulated device.

http://www.openwall.com/lists/oss-security/2015/12/14/9 :
 Qemu emulator built with the USB EHCI emulation support is vulnerable to an 
 infinite loop issue. It occurs during communication between host controller 
 interface(EHCI) and a respective device driver. These two communicate via a 
 isochronous transfer descriptor list(iTD) and an infinite loop unfolds if 
 there is a closed loop in this list.

 A privileges user inside guest could use this flaw to consume excessive CPU 
 cycles & resources on the host.

Reporting it existing in version 0.14 of qemu (this is where ehci device has
been introduced).