path: root/arch/x86/kvm/lapic.c
diff options
authorLinus Torvalds <>2021-06-17 13:14:53 -0700
committerLinus Torvalds <>2021-06-17 13:14:53 -0700
commitfd0aa1a4567d0f09e1bfe367a950b004f99ac290 (patch)
tree103d692c49e43a1154ccc2f6aac57fc9ea834121 /arch/x86/kvm/lapic.c
parent39519f6a56e398544d270fcb548de99b54421d43 (diff)
parentd8ac05ea13d789d5491a5920d70a05659015441d (diff)
Merge tag 'for-linus' of git://
Pull kvm fixes from Paolo Bonzini: "Miscellaneous bugfixes. The main interesting one is a NULL pointer dereference reported by syzkaller ("KVM: x86: Immediately reset the MMU context when the SMM flag is cleared")" * tag 'for-linus' of git:// KVM: selftests: Fix kvm_check_cap() assertion KVM: x86/mmu: Calculate and check "full" mmu_role for nested MMU KVM: X86: Fix x86_emulator slab cache leak KVM: SVM: Call SEV Guest Decommission if ASID binding fails KVM: x86: Immediately reset the MMU context when the SMM flag is cleared KVM: x86: Fix fall-through warnings for Clang KVM: SVM: fix doc warnings KVM: selftests: Fix compiling errors when initializing the static structure kvm: LAPIC: Restore guard to prevent illegal APIC register access
Diffstat (limited to 'arch/x86/kvm/lapic.c')
1 files changed, 3 insertions, 0 deletions
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 6d72d8f43310..17fa4ab1b834 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -1410,6 +1410,9 @@ int kvm_lapic_reg_read(struct kvm_lapic *apic, u32 offset, int len,
if (!apic_x2apic_mode(apic))
valid_reg_mask |= APIC_REG_MASK(APIC_ARBPRI);
+ if (alignment + len > 4)
+ return 1;
if (offset > 0x3f0 || !(valid_reg_mask & APIC_REG_MASK(offset)))
return 1;