- Correct unusable flag check on SS, DS, ES, FS, GS, and LDTR - Add IDTR and GDTR checks - Add rflags checks
Signed-off-by: Mohammed Gamal <[email protected]> --- arch/x86/kvm/vmx.c | 64 ++++++++++++++++++++++++++++++++++++++++++++++++--- 1 files changed, 60 insertions(+), 4 deletions(-) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 777e00d..f736008 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -2122,7 +2122,7 @@ static bool stack_segment_valid(struct kvm_vcpu *vcpu) ss_rpl = ss.selector & SELECTOR_RPL_MASK; if (ss.unusable) - return true; + return false; if (ss.type != 3 && ss.type != 7) return false; if (!ss.s) @@ -2144,7 +2144,7 @@ static bool data_segment_valid(struct kvm_vcpu *vcpu, int seg) rpl = var.selector & SELECTOR_RPL_MASK; if (var.unusable) - return true; + return false; if (!var.s) return false; if (!var.present) @@ -2185,7 +2185,7 @@ static bool ldtr_valid(struct kvm_vcpu *vcpu) vmx_get_segment(vcpu, &ldtr, VCPU_SREG_LDTR); if (ldtr.unusable) - return true; + return false; if (ldtr.selector & SELECTOR_TI_MASK) /* TI = 1 */ return false; if (ldtr.type != 2) @@ -2196,6 +2196,23 @@ static bool ldtr_valid(struct kvm_vcpu *vcpu) return true; } +static bool gdtr_idtr_valid(struct kvm_vcpu *vcpu) +{ + struct desc_ptr gdt; + struct desc_ptr idt; + + vmx_get_gdt(vcpu, &gdt); + vmx_get_idt(vcpu, &idt); + + if (gdt.size & 0xffff0000) + return false; + + if (idt.size & 0xffff0000) + return false; + + return true; +} + static bool cs_ss_rpl_check(struct kvm_vcpu *vcpu) { struct kvm_segment cs, ss; @@ -2207,6 +2224,41 @@ static bool cs_ss_rpl_check(struct kvm_vcpu *vcpu) (ss.selector & SELECTOR_RPL_MASK)); } +static bool rflags_valid(struct kvm_vcpu *vcpu) +{ + unsigned long rflags; + u32 entry_intr_info; + + rflags = vmcs_readl(GUEST_RFLAGS); + entry_intr_info = vmcs_read32(VM_ENTRY_INTR_INFO_FIELD); +#ifdef CONFIG_X86_64 + if (rflags & 0xffffffffffc00000) + return false; + if (is_long_mode(vcpu)) + if (rflags & X86_EFLAGS_VM) + return false; +#else + if (rflags & 0xffc00000) + return false; +#endif + if (rflags & 0x8000) + return false; + if (rflags & 0x20) + return false; + if (rflags & 0x8) + return false; + if (!(rflags & 0x2)) + return false; + + if ((entry_intr_info & INTR_INFO_INTR_TYPE_MASK) == INTR_TYPE_EXT_INTR + && (entry_intr_info & INTR_INFO_VALID_MASK)) { + if (!(rflags & X86_EFLAGS_IF)) + return false; + } + + return true; +} + /* * Check if guest state is valid. Returns true if valid, false if * not. @@ -2251,8 +2303,11 @@ static bool guest_state_valid(struct kvm_vcpu *vcpu) } /* TODO: * - Add checks on RIP - * - Add checks on RFLAGS */ + if (!rflags_valid(vcpu)) + return false; + if (!gdtr_idtr_valid(vcpu)) + return false; return true; } @@ -3559,6 +3614,7 @@ static int handle_invalid_guest_state(struct kvm_vcpu *vcpu) } if (err != EMULATE_DONE) { + kvm_report_emulation_failure(vcpu, "invalid guest state handler"); vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR; vcpu->run->internal.suberror = KVM_INTERNAL_ERROR_EMULATION; vcpu->run->internal.ndata = 0; -- 1.7.0.4 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
