[PATCH v3 6/9] KVM: arm64: __ubsan_handle_load_invalid_value EL2 implementation.

From: Elena Petrova <lenaptr@google.com>
To: kvmarm@lists.cs.columbia.edu
Cc: Elena Petrova <lenaptr@google.com>,
	linux-arm-kernel@lists.infradead.org,
	open list <linux-kernel@vger.kernel.org>,
	Marc Zyngier <maz@kernel.org>, James Morse <james.morse@arm.com>,
	Julien Thierry <julien.thierry.kdev@gmail.com>,
	Suzuki K Poulose <suzuki.poulose@arm.com>,
	George Popescu <george.apopescu97@gmail.com>,
	George Popescu <georgepope@google.com>
Subject: [PATCH v3 6/9] KVM: arm64: __ubsan_handle_load_invalid_value EL2 implementation.
Date: Fri, 15 Jan 2021 17:18:27 +0000	[thread overview]
Message-ID: <20210115171830.3602110-7-lenaptr@google.com> (raw)
In-Reply-To: <20210115171830.3602110-1-lenaptr@google.com>

From: George Popescu <georgepope@google.com>

The handler for the load invalid value undefined behaviour is
implemented at EL2. The EL2 handler's parameters are stored inside the buffer.
They are used by the symetric handler from EL1.

Signed-off-by: George Popescu <georgepope@google.com>
Signed-off-by: Elena Petrova <lenaptr@google.com>
---
 arch/arm64/include/asm/kvm_ubsan.h |  5 ++++-
 arch/arm64/kvm/hyp/nvhe/ubsan.c    | 14 +++++++++++++-
 arch/arm64/kvm/kvm_ubsan_buffer.c  |  6 +++++-
 3 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/arch/arm64/include/asm/kvm_ubsan.h b/arch/arm64/include/asm/kvm_ubsan.h
index 0eef0e11a93b..95ac6728ffd1 100644
--- a/arch/arm64/include/asm/kvm_ubsan.h
+++ b/arch/arm64/include/asm/kvm_ubsan.h
@@ -20,12 +20,14 @@ struct kvm_ubsan_info {
 	enum {
 		UBSAN_OUT_OF_BOUNDS,
 		UBSAN_UNREACHABLE_DATA,
-		UBSAN_SHIFT_OUT_OF_BOUNDS
+		UBSAN_SHIFT_OUT_OF_BOUNDS,
+		UBSAN_INVALID_DATA
 	} type;
 	union {
 		struct out_of_bounds_data out_of_bounds_data;
 		struct unreachable_data unreachable_data;
 		struct shift_out_of_bounds_data shift_out_of_bounds_data;
+		struct invalid_value_data invalid_value_data;
 	};
 	union {
 		struct ubsan_values u_val;
@@ -35,3 +37,4 @@ struct kvm_ubsan_info {
 void __ubsan_handle_out_of_bounds(void *_data, void *index);
 void __ubsan_handle_builtin_unreachable(void *_data);
 void __ubsan_handle_shift_out_of_bounds(void *_data, void *lhs, void *rhs);
+void __ubsan_handle_load_invalid_value(void *_data, void *val);
diff --git a/arch/arm64/kvm/hyp/nvhe/ubsan.c b/arch/arm64/kvm/hyp/nvhe/ubsan.c
index 1069ed5036d5..3143f7722be2 100644
--- a/arch/arm64/kvm/hyp/nvhe/ubsan.c
+++ b/arch/arm64/kvm/hyp/nvhe/ubsan.c
@@ -82,4 +82,16 @@ void __ubsan_handle_builtin_unreachable(void *_data)
 	}
 }
 
-void __ubsan_handle_load_invalid_value(void *_data, void *val) {}
+void __ubsan_handle_load_invalid_value(void *_data, void *val)
+{
+	struct kvm_ubsan_info *slot;
+	struct invalid_value_data *data = _data;
+
+	slot = kvm_ubsan_buffer_next_slot();
+	if (slot) {
+		slot->type = UBSAN_INVALID_DATA;
+		slot->invalid_value_data = *data;
+		slot->u_val.lval = val;
+	}
+
+}
diff --git a/arch/arm64/kvm/kvm_ubsan_buffer.c b/arch/arm64/kvm/kvm_ubsan_buffer.c
index b80045883047..5439f7a91636 100644
--- a/arch/arm64/kvm/kvm_ubsan_buffer.c
+++ b/arch/arm64/kvm/kvm_ubsan_buffer.c
@@ -31,7 +31,11 @@ void __kvm_check_ubsan_data(struct kvm_ubsan_info *slot)
         	__ubsan_handle_shift_out_of_bounds(&slot->shift_out_of_bounds_data,
 				slot->u_val.lval, slot->u_val.rval);
 		break;
-	}
+	case UBSAN_INVALID_DATA:
+		__ubsan_handle_load_invalid_value(&slot->invalid_value_data,
+				slot->u_val.lval);
+		break;
+    	}
 }
 
 void iterate_kvm_ubsan_buffer(unsigned long left, unsigned long right)
-- 
2.30.0.296.g2bfb1c46d8-goog

