Re: CVE request: Qemu: scsi: pvscsi: OOB read and infinite loop while setting descriptor rings

[cve-assign () mitre org]

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> Quick Emulator(Qemu) built with the VMWARE PVSCSI paravirtual SCSI bus
> emulation support is vulnerable to an OOB access and/or infinite loop issue.
> It could occur while processing SCSI commands 'PVSCSI_CMD_SETUP_RINGS'.
>
> A privileged user inside guest could use this flaw to crash the Qemu process
> resulting in DoS.
>
> https://lists.gnu.org/archive/html/qemu-devel/2016-09/msg00050.html
> https://bugzilla.redhat.com/show_bug.cgi?id=1373462

> > Vmware Paravirtual SCSI emulation uses command descriptors to
> > process SCSI commands. These descriptors come with their ring
> > buffers. A guest could set the page count for these rings to
> > an arbitrary value, leading to infinite loop or OOB access.
> > Add check to avoid it.

Use CVE-2016-7155.

This is not yet available at
http://git.qemu.org/?p=qemu.git;a=history;f=hw/scsi/vmw_pvscsi.c but
that may be an expected place for a later update.

- -- 
CVE Assignment Team
M/S M300, 202 Burlington Road, Bedford, MA 01730 USA
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