src/share/classes/java/util/zip/ZipOutputStream.java

@@ -661,10 +661,13 @@
         int len = extra.length;
         int off = 0;
         while (off + 4 <= len) {
             int tag = get16(extra, off);
             int sz = get16(extra, off + 2);
+            if (sz < 0 || (off + 4 + sz) > len) {
+                break;
+            }
             if (tag == EXTID_EXTT || tag == EXTID_ZIP64) {
                 skipped += (sz + 4);
             }
             off += (sz + 4);
         }

@@ -682,15 +685,22 @@
             int len = extra.length;
             int off = 0;
             while (off + 4 <= len) {
                 int tag = get16(extra, off);
                 int sz = get16(extra, off + 2);
+                if (sz < 0 || (off + 4 + sz) > len) {
+                    writeBytes(extra, off, len - off);
+                    return;
+                }
                 if (tag != EXTID_EXTT && tag != EXTID_ZIP64) {
                     writeBytes(extra, off, sz + 4);
                 }
                 off += (sz + 4);
             }
+            if (off < len) {
+                writeBytes(extra, off, len - off);
+            }
         }
     }
 
     /*
      * Writes a 8-bit byte to the output stream.