Oracle VM Security Advisory OVMSA-2017-0008

The following updated rpms for Oracle VM 3.3 have been uploaded to the 
Unbreakable Linux Network:



Description of changes:

- From: Andrew Cooper <>
   Date: Sun, 18 Dec 2016 15:42:59 +0000
   Subject: [PATCH] x86/emul: Correct the handling of eflags with SYSCALL
   A singlestep #DB is determined by the resulting eflags value from the
   execution of SYSCALL, not the original eflags value.
   By using the original eflags value, we negate the guest kernels 
attempt to
   protect itself from a privilege escalation by masking TF.
   Introduce a tf boolean and have the SYSCALL emulation recalculate it
   after the instruction is complete.
   This is XSA-204
   Signed-off-by: Andrew Cooper <>
   Reviewed-by: Jan Beulich <>
   Backported-by: Zhenzhong Duan <> [bug 25294894]

- From: Jan Beulich <>
   Subject: x86: force EFLAGS.IF on when exiting to PV guests
   Guest kernels modifying instructions in the process of being emulated
   for another of their vCPU-s may effect EFLAGS.IF to be cleared upon
   next exiting to guest context, by converting the being emulated
   instruction to CLI (at the right point in time). Prevent any such bad
   effects by always forcing EFLAGS.IF on. And to cover hypothetical other
   similar issues, also force EFLAGS.{IOPL,NT,VM} to zero.
   This is XSA-202.
   Signed-off-by: Jan Beulich <>
   Backported-by: Zhenzhong Duan <>
   Reviewed-by: Boris Ostrovsky <> [bug 25235035]

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