diff --git a/src/hotspot/share/logging/logAsyncWriter.cpp b/src/hotspot/share/logging/logAsyncWriter.cpp
index 25292503f3d..178adf22d49 100644
--- a/src/hotspot/share/logging/logAsyncWriter.cpp
+++ b/src/hotspot/share/logging/logAsyncWriter.cpp
@@ -1,5 +1,6 @@
 /*
  * Copyright Amazon.com Inc. or its affiliates. All Rights Reserved.
+ * Copyright (c) 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -48,13 +49,14 @@ const LogDecorations& AsyncLogWriter::None = LogDecorations(LogLevel::Warning, L
                                       LogDecorators::None);
 
 bool AsyncLogWriter::Buffer::push_back(LogFileStreamOutput* output, const LogDecorations& decorations, const char* msg) {
-  const size_t sz = Message::calc_size(strlen(msg));
+  const size_t len = strlen(msg);
+  const size_t sz = Message::calc_size(len);
   const bool is_token = output == nullptr;
   // Always leave headroom for the flush token. Pushing a token must succeed.
   const size_t headroom = (!is_token) ? Message::calc_size(0) : 0;
 
   if (_pos + sz <= (_capacity - headroom)) {
-    new(_buf + _pos) Message(output, decorations, msg);
+    new(_buf + _pos) Message(output, decorations, msg, len);
     _pos += sz;
     return true;
   }
diff --git a/src/hotspot/share/logging/logAsyncWriter.hpp b/src/hotspot/share/logging/logAsyncWriter.hpp
index 02397f633f7..bd6fcd20a52 100644
--- a/src/hotspot/share/logging/logAsyncWriter.hpp
+++ b/src/hotspot/share/logging/logAsyncWriter.hpp
@@ -1,5 +1,6 @@
 /*
  * Copyright Amazon.com Inc. or its affiliates. All Rights Reserved.
+ * Copyright (c) 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -66,13 +67,13 @@ class AsyncLogWriter : public NonJavaThread {
                           uint32_t, 17, /*table_size*/
                           ALLOC_TYPE, mtLogging>;
 
-  // Messsage is the envelop of a log line and its associative data.
+  // Messsage is the envelope of a log line and its associative data.
   // Its length is variable because of the zero-terminated c-str. It is only valid when we create it using placement new
   // within a buffer.
   //
   // Example layout:
   // ---------------------------------------------
-  // |_output|_decorations|"a log line", |pad| <- pointer aligned.
+  // |_output|_decorations|"a log line", |pad| <- Message aligned.
   // |_output|_decorations|"yet another",|pad|
   // ...
   // |nullptr|_decorations|"",|pad| <- flush token
@@ -84,16 +85,16 @@ class AsyncLogWriter : public NonJavaThread {
     LogFileStreamOutput* const _output;
     const LogDecorations _decorations;
    public:
-    Message(LogFileStreamOutput* output, const LogDecorations& decorations, const char* msg)
+    // msglen excludes NUL-byte
+    Message(LogFileStreamOutput* output, const LogDecorations& decorations, const char* msg, const size_t msglen)
       : _output(output), _decorations(decorations) {
       assert(msg != nullptr, "c-str message can not be null!");
-      PRAGMA_STRINGOP_OVERFLOW_IGNORED
-      strcpy(reinterpret_cast<char* >(this+1), msg);
+      memcpy(reinterpret_cast<char* >(this+1), msg, msglen + 1);
     }
 
     // Calculate the size for a prospective Message object depending on its message length including the trailing zero
     static constexpr size_t calc_size(size_t message_len) {
-      return align_up(sizeof(Message) + message_len + 1, sizeof(void*));
+      return align_up(sizeof(Message) + message_len + 1, alignof(Message));
     }
 
     size_t size() const {
@@ -114,6 +115,8 @@ class AsyncLogWriter : public NonJavaThread {
    public:
     Buffer(size_t capacity) :  _pos(0), _capacity(capacity) {
       _buf = NEW_C_HEAP_ARRAY(char, capacity, mtLogging);
+      // Ensure _pos is Message-aligned
+      _pos = align_up(_buf, alignof(Message)) - _buf;
       assert(capacity >= Message::calc_size(0), "capcity must be great a token size");
     }
 
@@ -124,7 +127,10 @@ class AsyncLogWriter : public NonJavaThread {
     void push_flush_token();
     bool push_back(LogFileStreamOutput* output, const LogDecorations& decorations, const char* msg);
 
-    void reset() { _pos = 0; }
+    void reset() {
+      // Ensure _pos is Message-aligned
+      _pos = align_up(_buf, alignof(Message)) - _buf;
+    }
 
     class Iterator {
       const Buffer& _buf;