diff options
| author | Sean Christopherson <seanjc@google.com> | 2026-02-25 04:20:48 +0300 |
|---|---|---|
| committer | Sean Christopherson <seanjc@google.com> | 2026-03-03 03:02:53 +0300 |
| commit | 4f09e62afcd6c7a2c3428a3453ced7e56475dc70 (patch) | |
| tree | 7c8158281d6e8c18f1e1381634897c5deaf8dc98 | |
| parent | 216729846603d5be668a84d75c88ae097c27ae61 (diff) | |
| download | linux-4f09e62afcd6c7a2c3428a3453ced7e56475dc70.tar.xz | |
KVM: x86: Don't panic the kernel if completing userspace I/O / MMIO goes sideways
Kill the VM instead of the host kernel if KVM botches I/O and/or MMIO
handling. There is zero danger to the host or guest, i.e. panicking the
host isn't remotely justified.
Tested-by: Tom Lendacky <thomas.lendacky@gmail.com>
Tested-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Link: https://patch.msgid.link/20260225012049.920665-14-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
| -rw-r--r-- | arch/x86/kvm/x86.c | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index cbd377bf71ba..1467652ceabc 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -9709,7 +9709,8 @@ static int complete_fast_pio_in(struct kvm_vcpu *vcpu) unsigned long val; /* We should only ever be called with arch.pio.count equal to 1 */ - BUG_ON(vcpu->arch.pio.count != 1); + if (KVM_BUG_ON(vcpu->arch.pio.count != 1, vcpu->kvm)) + return -EIO; if (unlikely(!kvm_is_linear_rip(vcpu, vcpu->arch.cui_linear_rip))) { vcpu->arch.pio.count = 0; @@ -11819,7 +11820,8 @@ static inline int complete_emulated_io(struct kvm_vcpu *vcpu) static int complete_emulated_pio(struct kvm_vcpu *vcpu) { - BUG_ON(!vcpu->arch.pio.count); + if (KVM_BUG_ON(!vcpu->arch.pio.count, vcpu->kvm)) + return -EIO; return complete_emulated_io(vcpu); } @@ -11848,7 +11850,8 @@ static int complete_emulated_mmio(struct kvm_vcpu *vcpu) struct kvm_mmio_fragment *frag; unsigned len; - BUG_ON(!vcpu->mmio_needed); + if (KVM_BUG_ON(!vcpu->mmio_needed, vcpu->kvm)) + return -EIO; /* Complete previous fragment */ frag = &vcpu->mmio_fragments[vcpu->mmio_cur_fragment]; @@ -14261,7 +14264,8 @@ static int complete_sev_es_emulated_mmio(struct kvm_vcpu *vcpu) struct kvm_mmio_fragment *frag; unsigned int len; - BUG_ON(!vcpu->mmio_needed); + if (KVM_BUG_ON(!vcpu->mmio_needed, vcpu->kvm)) + return -EIO; /* Complete previous fragment */ frag = &vcpu->mmio_fragments[vcpu->mmio_cur_fragment]; |