The compat_iret function in Xen 3.1 through 4.5 iterates the wrong way through a loop, which allows local 32-bit PV guest administrators to cause a denial of service (large loop and system hang) via a hypercall_iret call with EFLAGS.VM set.
openSUSE 13.1 openSUSE 13.2 SUSE Linux Enterprise Desktop 11 SP3 SUSE Linux Enterprise Desktop 11 SP4 SUSE Linux Enterprise Desktop 12 SUSE Linux Enterprise Server 10 SP4 LTSS for AMD64 and Intel EM64T SUSE Linux Enterprise Server 10 SP4 LTSS for x86 SUSE Linux Enterprise Server 11 SP1 for Teradata SUSE Linux Enterprise Server 11 SP1 LTSS SUSE Linux Enterprise Server 11 SP1-LTSS SUSE Linux Enterprise Server 11 SP1-TERADATA SUSE Linux Enterprise Server 11 SP2 LTSS SUSE Linux Enterprise Server 11 SP2-LTSS SUSE Linux Enterprise Server 11 SP3 SUSE Linux Enterprise Server 11 SP3 for Teradata SUSE Linux Enterprise Server 11 SP3-TERADATA SUSE Linux Enterprise Server 11 SP4 SUSE Linux Enterprise Server 12 SUSE Linux Enterprise Server for SAP Applications 11 SP1-LTSS SUSE Linux Enterprise Server for SAP Applications 11 SP1-TERADATA SUSE Linux Enterprise Server for SAP Applications 11 SP2-LTSS SUSE Linux Enterprise Server for SAP Applications 11 SP3 SUSE Linux Enterprise Server for SAP Applications 11 SP3-TERADATA SUSE Linux Enterprise Server for SAP Applications 11 SP4 SUSE Linux Enterprise Server for SAP Applications 12 SUSE Linux Enterprise Software Development Kit 11 SP3 SUSE Linux Enterprise Software Development Kit 11 SP4 SUSE Linux Enterprise Software Development Kit 12 SUSE Linux Enterprise Teradata 10 SP3 for AMD64 and Intel EM64T