From 933e3e2b5070058097089d77281ce2704d031070 Mon Sep 17 00:00:00 2001 From: Jan Dakinevich Date: Tue, 27 Aug 2019 13:07:08 +0000 Subject: [PATCH] KVM: x86: set ctxt->have_exception in x86_decode_insn() commit c8848cee74ff05638e913582a476bde879c968ad upstream. x86_emulate_instruction() takes into account ctxt->have_exception flag during instruction decoding, but in practice this flag is never set in x86_decode_insn(). Fixes: 6ea6e84309ca ("KVM: x86: inject exceptions produced by x86_decode_insn") Cc: stable@vger.kernel.org Cc: Denis Lunev Cc: Roman Kagan Cc: Denis Plotnikov Signed-off-by: Jan Dakinevich Signed-off-by: Paolo Bonzini Signed-off-by: Greg Kroah-Hartman --- arch/x86/kvm/emulate.c | 2 ++ arch/x86/kvm/x86.c | 6 ++++++ 2 files changed, 8 insertions(+) diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index 429728b..e699f4d 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -5368,6 +5368,8 @@ done_prefixes: ctxt->memopp->addr.mem.ea + ctxt->_eip); done: + if (rc == X86EMUL_PROPAGATE_FAULT) + ctxt->have_exception = true; return (rc != X86EMUL_CONTINUE) ? EMULATION_FAILED : EMULATION_OK; } diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index a8892f7..162fed4 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -6245,6 +6245,12 @@ int x86_emulate_instruction(struct kvm_vcpu *vcpu, emulation_type)) return EMULATE_DONE; if (ctxt->have_exception) { + /* + * #UD should result in just EMULATION_FAILED, and trap-like + * exception should not be encountered during decode. + */ + WARN_ON_ONCE(ctxt->exception.vector == UD_VECTOR || + exception_type(ctxt->exception.vector) == EXCPT_TRAP); inject_emulated_exception(vcpu); return EMULATE_DONE; } -- 2.7.4