Add error handling for too large rip relative displacements

zyantific · May 1, 2024 · 0cb0e70 · 0cb0e70
1 parent f04bc83
commit 0cb0e70
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diff --git a/src/tests/tests/tests.serialization.cpp b/src/tests/tests/tests.serialization.cpp
@@ -1240,4 +1240,21 @@ namespace zasm::tests
         ASSERT_EQ(res, ErrorCode::None);
     }
 
+    TEST(SerializationTests, TestBadMemoryDisplacement)
+    {
+        Program program(MachineMode::AMD64);
+
+        x86::Assembler a(program);
+        ASSERT_EQ(a.mov(x86::rax, x86::qword_ptr(x86::rip, 0xF23456789)), ErrorCode::None);
+
+        Serializer serializer;
+        auto res = serializer.serialize(program, 0x140015000);
+        ASSERT_EQ(res, ErrorCode::AddressOutOfRange);
+
+        ASSERT_EQ(
+            res.getErrorMessage(),
+            std::string("Error at node \"mov rax, qword ptr ds:[rel 0xf23456789]\" with id 0: Displacement out of range for "
+                        "operand 1"));
+    }
+
 } // namespace zasm::tests
diff --git a/src/zasm/src/encoder/encoder.cpp b/src/zasm/src/encoder/encoder.cpp
@@ -390,6 +390,13 @@ namespace zasm
                 if (isDisplacementValid)
                 {
                     displacement = displacement - (address + instrSize);
+                    if (std::abs(displacement) > std::numeric_limits<std::int32_t>::max())
+                    {
+                        char msg[128];
+                        std::snprintf(msg, sizeof(msg), "Displacement out of range for operand %zu", state.operandIndex);
+
+                        return Error(ErrorCode::AddressOutOfRange, msg);
+                    }
                 }
             }