8165344: Update concurrency support

Reviewed-by: psandoz

src/share/classes/java/util/concurrent/atomic/AtomicIntegerFieldUpdater.java

@@ -40,6 +40,7 @@ import java.lang.reflect.Modifier;
 import java.security.AccessController;
 import java.security.PrivilegedActionException;
 import java.security.PrivilegedExceptionAction;
+import java.util.Objects;
 import java.util.function.IntBinaryOperator;
 import java.util.function.IntUnaryOperator;
 import sun.reflect.CallerSensitive;
@@ -410,7 +411,17 @@ public abstract class AtomicIntegerFieldUpdater<T> {
             if (!Modifier.isVolatile(modifiers))
                 throw new IllegalArgumentException("Must be volatile type");
 
-            this.cclass = (Modifier.isProtected(modifiers)) ? caller : tclass;
+            // Access to protected field members is restricted to receivers only
+            // of the accessing class, or one of its subclasses, and the
+            // accessing class must in turn be a subclass (or package sibling)
+            // of the protected member's defining class.
+            // If the updater refers to a protected field of a declaring class
+            // outside the current package, the receiver argument will be
+            // narrowed to the type of the accessing class.
+            this.cclass = (Modifier.isProtected(modifiers) &&
+                           tclass.isAssignableFrom(caller) &&
+                           !isSamePackage(tclass, caller))
+                          ? caller : tclass;
             this.tclass = tclass;
             this.offset = U.objectFieldOffset(field);
         }
@@ -431,6 +442,21 @@ public abstract class AtomicIntegerFieldUpdater<T> {
             return false;
         }
 
+        /**
+         * Returns true if the two classes have the same class loader and
+         * package qualifier
+         */
+        private static boolean isSamePackage(Class<?> class1, Class<?> class2) {
+            return class1.getClassLoader() == class2.getClassLoader()
+                   && Objects.equals(getPackageName(class1), getPackageName(class2));
+        }
+
+        private static String getPackageName(Class<?> cls) {
+            String cn = cls.getName();
+            int dot = cn.lastIndexOf('.');
+            return (dot != -1) ? cn.substring(0, dot) : "";
+        }
+
         /**
          * Checks that target argument is instance of cclass.  On
          * failure, throws cause.

src/share/classes/java/util/concurrent/atomic/AtomicLongFieldUpdater.java

@@ -40,6 +40,7 @@ import java.lang.reflect.Modifier;
 import java.security.AccessController;
 import java.security.PrivilegedActionException;
 import java.security.PrivilegedExceptionAction;
+import java.util.Objects;
 import java.util.function.LongBinaryOperator;
 import java.util.function.LongUnaryOperator;
 import sun.reflect.CallerSensitive;
@@ -408,7 +409,17 @@ public abstract class AtomicLongFieldUpdater<T> {
             if (!Modifier.isVolatile(modifiers))
                 throw new IllegalArgumentException("Must be volatile type");
 
-            this.cclass = (Modifier.isProtected(modifiers)) ? caller : tclass;
+            // Access to protected field members is restricted to receivers only
+            // of the accessing class, or one of its subclasses, and the
+            // accessing class must in turn be a subclass (or package sibling)
+            // of the protected member's defining class.
+            // If the updater refers to a protected field of a declaring class
+            // outside the current package, the receiver argument will be
+            // narrowed to the type of the accessing class.
+            this.cclass = (Modifier.isProtected(modifiers) &&
+                           tclass.isAssignableFrom(caller) &&
+                           !isSamePackage(tclass, caller))
+                          ? caller : tclass;
             this.tclass = tclass;
             this.offset = U.objectFieldOffset(field);
         }
@@ -539,7 +550,17 @@ public abstract class AtomicLongFieldUpdater<T> {
             if (!Modifier.isVolatile(modifiers))
                 throw new IllegalArgumentException("Must be volatile type");
 
-            this.cclass = (Modifier.isProtected(modifiers)) ? caller : tclass;
+            // Access to protected field members is restricted to receivers only
+            // of the accessing class, or one of its subclasses, and the
+            // accessing class must in turn be a subclass (or package sibling)
+            // of the protected member's defining class.
+            // If the updater refers to a protected field of a declaring class
+            // outside the current package, the receiver argument will be
+            // narrowed to the type of the accessing class.
+            this.cclass = (Modifier.isProtected(modifiers) &&
+                           tclass.isAssignableFrom(caller) &&
+                           !isSamePackage(tclass, caller))
+                          ? caller : tclass;
             this.tclass = tclass;
             this.offset = U.objectFieldOffset(field);
         }
@@ -620,4 +641,19 @@ public abstract class AtomicLongFieldUpdater<T> {
         } while (acl != null);
         return false;
     }
+
+    /**
+     * Returns true if the two classes have the same class loader and
+     * package qualifier
+     */
+    private static boolean isSamePackage(Class<?> class1, Class<?> class2) {
+        return class1.getClassLoader() == class2.getClassLoader()
+               && Objects.equals(getPackageName(class1), getPackageName(class2));
+}
+
+    private static String getPackageName(Class<?> cls) {
+        String cn = cls.getName();
+        int dot = cn.lastIndexOf('.');
+        return (dot != -1) ? cn.substring(0, dot) : "";
+    }
 }

src/share/classes/java/util/concurrent/atomic/AtomicReferenceFieldUpdater.java

@@ -40,6 +40,7 @@ import java.lang.reflect.Modifier;
 import java.security.AccessController;
 import java.security.PrivilegedActionException;
 import java.security.PrivilegedExceptionAction;
+import java.util.Objects;
 import java.util.function.BinaryOperator;
 import java.util.function.UnaryOperator;
 import sun.reflect.CallerSensitive;
@@ -346,7 +347,17 @@ public abstract class AtomicReferenceFieldUpdater<T,V> {
             if (!Modifier.isVolatile(modifiers))
                 throw new IllegalArgumentException("Must be volatile type");
 
-            this.cclass = (Modifier.isProtected(modifiers)) ? caller : tclass;
+            // Access to protected field members is restricted to receivers only
+            // of the accessing class, or one of its subclasses, and the
+            // accessing class must in turn be a subclass (or package sibling)
+            // of the protected member's defining class.
+            // If the updater refers to a protected field of a declaring class
+            // outside the current package, the receiver argument will be
+            // narrowed to the type of the accessing class.
+            this.cclass = (Modifier.isProtected(modifiers) &&
+                           tclass.isAssignableFrom(caller) &&
+                           !isSamePackage(tclass, caller))
+                          ? caller : tclass;
             this.tclass = tclass;
             this.vclass = vclass;
             this.offset = U.objectFieldOffset(field);
@@ -368,6 +379,21 @@ public abstract class AtomicReferenceFieldUpdater<T,V> {
             return false;
         }
 
+        /**
+         * Returns true if the two classes have the same class loader and
+         * package qualifier
+         */
+        private static boolean isSamePackage(Class<?> class1, Class<?> class2) {
+            return class1.getClassLoader() == class2.getClassLoader()
+                   && Objects.equals(getPackageName(class1), getPackageName(class2));
+        }
+
+        private static String getPackageName(Class<?> cls) {
+            String cn = cls.getName();
+            int dot = cn.lastIndexOf('.');
+            return (dot != -1) ? cn.substring(0, dot) : "";
+        }
+
         /**
          * Checks that target argument is instance of cclass.  On
          * failure, throws cause.