From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ahmed Abd El Mawgood Subject: [RESEND PATCH V8 09/11] KVM: Add new exit reason For ROE violations Date: Mon, 21 Jan 2019 01:39:38 +0200 Message-Id: <20190120233940.15282-10-ahmedsoliman@mena.vt.edu> In-Reply-To: <20190120233940.15282-1-ahmedsoliman@mena.vt.edu> References: <20190120233940.15282-1-ahmedsoliman@mena.vt.edu> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit To: Paolo Bonzini , rkrcmar@redhat.com, Jonathan Corbet , Thomas Gleixner , Ingo Molnar , Borislav Petkov , hpa@zytor.com, x86@kernel.org, kvm@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, ahmedsoliman0x666@gmail.com, ovich00@gmail.com, kernel-hardening@lists.openwall.com, nigel.edwards@hpe.com, Boris Lukashev , Igor Stoppa Cc: Ahmed Abd El Mawgood List-ID: The problem is that qemu will not be able to detect ROE violations, so one option would be create host API to tell if a given page is ROE protected, or create ROE violation exit reason. Signed-off-by: Ahmed Abd El Mawgood --- arch/x86/kvm/x86.c | 10 +++++++++- include/kvm/roe.h | 12 ++++++++++++ include/uapi/linux/kvm.h | 2 +- virt/kvm/kvm_main.c | 1 + virt/kvm/roe.c | 2 +- virt/kvm/roe_generic.h | 9 +-------- 6 files changed, 25 insertions(+), 11 deletions(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 19b0f2307e..368e3d99fd 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -5409,6 +5409,7 @@ static int emulator_read_write(struct x86_emulate_ctxt *ctxt, const struct read_write_emulator_ops *ops) { struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt); + struct kvm_memory_slot *slot; gpa_t gpa; int rc; @@ -5450,7 +5451,14 @@ static int emulator_read_write(struct x86_emulate_ctxt *ctxt, vcpu->run->mmio.len = min(8u, vcpu->mmio_fragments[0].len); vcpu->run->mmio.is_write = vcpu->mmio_is_write = ops->write; - vcpu->run->exit_reason = KVM_EXIT_MMIO; + slot = kvm_vcpu_gfn_to_memslot(vcpu, gpa >> PAGE_SHIFT); + if (slot && ops->write && (kvm_roe_check_range(slot, gpa>>PAGE_SHIFT, + gpa - (gpa & PAGE_MASK), bytes) || + gfn_is_full_roe(slot, gpa>>PAGE_SHIFT))) + vcpu->run->exit_reason = KVM_EXIT_ROE; + else + vcpu->run->exit_reason = KVM_EXIT_MMIO; + vcpu->run->mmio.phys_addr = gpa; return ops->read_write_exit_mmio(vcpu, gpa, val, bytes); diff --git a/include/kvm/roe.h b/include/kvm/roe.h index 6a86866623..3121a67753 100644 --- a/include/kvm/roe.h +++ b/include/kvm/roe.h @@ -13,4 +13,16 @@ void kvm_roe_arch_commit_protection(struct kvm *kvm, struct kvm_memory_slot *slot); int kvm_roe(struct kvm_vcpu *vcpu, u64 a0, u64 a1, u64 a2, u64 a3); bool kvm_roe_arch_is_userspace(struct kvm_vcpu *vcpu); +bool kvm_roe_check_range(struct kvm_memory_slot *slot, gfn_t gfn, int offset, + int len); +static inline bool gfn_is_full_roe(struct kvm_memory_slot *slot, gfn_t gfn) +{ + return test_bit(gfn - slot->base_gfn, slot->roe_bitmap); + +} +static inline bool gfn_is_partial_roe(struct kvm_memory_slot *slot, gfn_t gfn) +{ + return test_bit(gfn - slot->base_gfn, slot->partial_roe_bitmap); +} + #endif diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index 6d4ea4b6c9..0a386bb5f2 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -235,7 +235,7 @@ struct kvm_hyperv_exit { #define KVM_EXIT_S390_STSI 25 #define KVM_EXIT_IOAPIC_EOI 26 #define KVM_EXIT_HYPERV 27 - +#define KVM_EXIT_ROE 28 /* For KVM_EXIT_INTERNAL_ERROR */ /* Emulate instruction failed. */ #define KVM_INTERNAL_ERROR_EMULATION 1 diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 819033f475..d92d300539 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -62,6 +62,7 @@ #include "async_pf.h" #include "vfio.h" #include "roe_generic.h" +#include #define CREATE_TRACE_POINTS #include diff --git a/virt/kvm/roe.c b/virt/kvm/roe.c index 4393a6a6a2..9540473f89 100644 --- a/virt/kvm/roe.c +++ b/virt/kvm/roe.c @@ -60,7 +60,7 @@ bool kvm_roe_check_range(struct kvm_memory_slot *slot, gfn_t gfn, int offset, return false; return kvm_roe_protected_range(slot, gpa, len); } - +EXPORT_SYMBOL_GPL(kvm_roe_check_range); void kvm_roe_free(struct kvm_memory_slot *slot) { diff --git a/virt/kvm/roe_generic.h b/virt/kvm/roe_generic.h index ad121372f2..f1ce4a8aec 100644 --- a/virt/kvm/roe_generic.h +++ b/virt/kvm/roe_generic.h @@ -14,12 +14,5 @@ void kvm_roe_free(struct kvm_memory_slot *slot); int kvm_roe_init(struct kvm_memory_slot *slot); bool kvm_roe_check_range(struct kvm_memory_slot *slot, gfn_t gfn, int offset, int len); -static inline bool gfn_is_full_roe(struct kvm_memory_slot *slot, gfn_t gfn) -{ - return test_bit(gfn - slot->base_gfn, slot->roe_bitmap); -} -static inline bool gfn_is_partial_roe(struct kvm_memory_slot *slot, gfn_t gfn) -{ - return test_bit(gfn - slot->base_gfn, slot->partial_roe_bitmap); -} + #endif -- 2.19.2