From bf0b682c9b6a6d6d54adf439bfe953feef7be2e8 Mon Sep 17 00:00:00 2001 From: Nadav Amit Date: Thu, 18 Sep 2014 22:39:45 +0300 Subject: [PATCH] KVM: x86: Sysexit emulation does not mask RIP/RSP If the operand size is not 64-bit, then the sysexit instruction should assign ECX to RSP and EDX to RIP. The current code assigns the full 64-bits. Fix it by masking. Signed-off-by: Nadav Amit Signed-off-by: Paolo Bonzini --- arch/x86/kvm/emulate.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index a90fa188aeea..058aff86cfba 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -2417,6 +2417,8 @@ static int em_sysexit(struct x86_emulate_ctxt *ctxt) if ((msr_data & 0xfffc) == 0x0) return emulate_gp(ctxt, 0); ss_sel = (u16)(msr_data + 24); + rcx = (u32)rcx; + rdx = (u32)rdx; break; case X86EMUL_MODE_PROT64: cs_sel = (u16)(msr_data + 32); -- 2.34.1