diff --git a/kernel.spec b/kernel.spec index 57382ac..8571c80 100644 --- a/kernel.spec +++ b/kernel.spec @@ -658,6 +658,9 @@ Patch717: KEYS-Fix-ASN.1-indefinite-length-object-parsing.patch #CVE-2016-3713 rhbz 1332139 1336410 Patch718: KVM-MTRR-remove-MSR-0x2f8.patch +#CVE-2016-4440 rhbz 1337806 1337807 +Patch719: kvm-vmx-more-complete-state-update-on-APICv-on-off.patch + # END OF PATCH DEFINITIONS %endif @@ -2179,6 +2182,9 @@ fi # # %changelog +* Fri May 20 2016 Josh Boyer +- CVE-2016-4440 kvm: incorrect state leading to APIC register access (rhbz 1337806 1337807) + * Thu May 19 2016 Josh Boyer - 4.5.5-200 - Linux v4.5.5 - CVE-2016-4913 isofs: info leak with malformed NM entries (rhbz 1337528 1337529) diff --git a/kvm-vmx-more-complete-state-update-on-APICv-on-off.patch b/kvm-vmx-more-complete-state-update-on-APICv-on-off.patch new file mode 100644 index 0000000..6704330 --- /dev/null +++ b/kvm-vmx-more-complete-state-update-on-APICv-on-off.patch @@ -0,0 +1,112 @@ +From: Roman Kagan +Subject: [PATCH v3] kvm:vmx: more complete state update on APICv on/off +Date: 2016-05-18 14:48:20 GMT (1 day, 21 hours and 23 minutes ago) + +The function to update APICv on/off state (in particular, to deactivate +it when enabling Hyper-V SynIC), used to be incomplete: it didn't adjust +APICv-related fields among secondary processor-based VM-execution +controls. + +As a result, Windows 2012 guests would get stuck when SynIC-based +auto-EOI interrupt intersected with e.g. an IPI in the guest. + +In addition, the MSR intercept bitmap wasn't updated to correspond to +whether "virtualize x2APIC mode" was enabled. This path used not to be +triggered, since Windows didn't use x2APIC but rather their own +synthetic APIC access MSRs; however it represented a security risk +because the guest running in a SynIC-enabled VM could switch to x2APIC +and thus obtain direct access to host APIC MSRs (thanks to Yang Zhang + for spotting this). + +The patch fixes those omissions. + +Signed-off-by: Roman Kagan +Cc: Steve Rutherford +Cc: Yang Zhang +--- +v2 -> v3: + - only switch to x2apic msr bitmap if virtualize x2apic mode is on in vmcs + +v1 -> v2: + - only update relevant bits in the secondary exec control + - update msr intercept bitmap (also make x2apic msr bitmap always + correspond to APICv) + + arch/x86/kvm/vmx.c | 48 ++++++++++++++++++++++++++++++------------------ + 1 file changed, 30 insertions(+), 18 deletions(-) + +diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c +index ee1c8a9..cef741a 100644 +--- a/arch/x86/kvm/vmx.c ++++ b/arch/x86/kvm/vmx.c +@@ -2418,7 +2418,9 @@ static void vmx_set_msr_bitmap(struct kvm_vcpu *vcpu) + + if (is_guest_mode(vcpu)) + msr_bitmap = vmx_msr_bitmap_nested; +- else if (vcpu->arch.apic_base & X2APIC_ENABLE) { ++ else if (cpu_has_secondary_exec_ctrls() && ++ (vmcs_read32(SECONDARY_VM_EXEC_CONTROL) & ++ SECONDARY_EXEC_VIRTUALIZE_X2APIC_MODE)) { + if (is_long_mode(vcpu)) + msr_bitmap = vmx_msr_bitmap_longmode_x2apic; + else +@@ -4783,6 +4785,19 @@ static void vmx_refresh_apicv_exec_ctrl(struct kvm_vcpu *vcpu) + struct vcpu_vmx *vmx = to_vmx(vcpu); + + vmcs_write32(PIN_BASED_VM_EXEC_CONTROL, vmx_pin_based_exec_ctrl(vmx)); ++ if (cpu_has_secondary_exec_ctrls()) { ++ if (kvm_vcpu_apicv_active(vcpu)) ++ vmcs_set_bits(SECONDARY_VM_EXEC_CONTROL, ++ SECONDARY_EXEC_APIC_REGISTER_VIRT | ++ SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY); ++ else ++ vmcs_clear_bits(SECONDARY_VM_EXEC_CONTROL, ++ SECONDARY_EXEC_APIC_REGISTER_VIRT | ++ SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY); ++ } ++ ++ if (cpu_has_vmx_msr_bitmap()) ++ vmx_set_msr_bitmap(vcpu); + } + + static u32 vmx_exec_control(struct vcpu_vmx *vmx) +@@ -6329,23 +6344,20 @@ static __init int hardware_setup(void) + + set_bit(0, vmx_vpid_bitmap); /* 0 is reserved for host */ + +- if (enable_apicv) { +- for (msr = 0x800; msr <= 0x8ff; msr++) +- vmx_disable_intercept_msr_read_x2apic(msr); +- +- /* According SDM, in x2apic mode, the whole id reg is used. +- * But in KVM, it only use the highest eight bits. Need to +- * intercept it */ +- vmx_enable_intercept_msr_read_x2apic(0x802); +- /* TMCCT */ +- vmx_enable_intercept_msr_read_x2apic(0x839); +- /* TPR */ +- vmx_disable_intercept_msr_write_x2apic(0x808); +- /* EOI */ +- vmx_disable_intercept_msr_write_x2apic(0x80b); +- /* SELF-IPI */ +- vmx_disable_intercept_msr_write_x2apic(0x83f); +- } ++ for (msr = 0x800; msr <= 0x8ff; msr++) ++ vmx_disable_intercept_msr_read_x2apic(msr); ++ ++ /* According SDM, in x2apic mode, the whole id reg is used. But in ++ * KVM, it only use the highest eight bits. Need to intercept it */ ++ vmx_enable_intercept_msr_read_x2apic(0x802); ++ /* TMCCT */ ++ vmx_enable_intercept_msr_read_x2apic(0x839); ++ /* TPR */ ++ vmx_disable_intercept_msr_write_x2apic(0x808); ++ /* EOI */ ++ vmx_disable_intercept_msr_write_x2apic(0x80b); ++ /* SELF-IPI */ ++ vmx_disable_intercept_msr_write_x2apic(0x83f); + + if (enable_ept) { + kvm_mmu_set_mask_ptes(0ull, +-- +2.5.5