Require in instantiate for imported memory size to be equal min limit

Author: gumb0

lib/fizzy/instantiate.cpp

@@ -121,9 +121,9 @@ void match_imported_memories(const std::vector<Memory>& module_imported_memories
 
         const auto min = imported_memories[0].limits.min;
         const auto& max = imported_memories[0].limits.max;
-        if (size < memory_pages_to_bytes(min) ||
+        if (size != memory_pages_to_bytes(min) ||
             (max.has_value() && size > memory_pages_to_bytes(*max)))
-            throw instantiate_error{"provided imported memory doesn't fit provided limits"};
+            throw instantiate_error{"provided imported memory size must be equal to its min limit"};
     }
 }
 

test/unittests/instantiate_test.cpp

@@ -302,12 +302,12 @@ TEST(instantiate, imported_memory_invalid)
 
     // Allocated less than min
     EXPECT_THROW_MESSAGE(instantiate(*module, {}, {}, {{&memory_empty, {1, 3}}}), instantiate_error,
-        "provided imported memory doesn't fit provided limits");
+        "provided imported memory size must be equal to its min limit");
 
-    // Allocated more than max
-    bytes memory_big(PageSize * 4, 0);
-    EXPECT_THROW_MESSAGE(instantiate(*module, {}, {}, {{&memory_big, {1, 3}}}), instantiate_error,
-        "provided imported memory doesn't fit provided limits");
+    // Allocated more than min but less than max
+    bytes memory_two_pages(PageSize * 2, 0);
+    EXPECT_THROW_MESSAGE(instantiate(*module, {}, {}, {{&memory_two_pages, {1, 3}}}),
+        instantiate_error, "provided imported memory size must be equal to its min limit");
 
     // Provided max exceeds the hard limit
     /* wat2wasm