diff --git a/bbootimg/src/main/kotlin/bootimg/v2/BootV2.kt b/bbootimg/src/main/kotlin/bootimg/v2/BootV2.kt
index da089ee..509ed6b 100644
--- a/bbootimg/src/main/kotlin/bootimg/v2/BootV2.kt
+++ b/bbootimg/src/main/kotlin/bootimg/v2/BootV2.kt
@@ -383,7 +383,8 @@ data class BootV2(
         }
 
         log.info("Writing data ...")
-        val bytesV2 = ByteBuffer.allocate(1024 * 1024 * 64)//assume total SIZE small than 64MB
+        //boot image size may > 64MB. Fix issue #57
+        val bytesV2 = ByteBuffer.allocate(maxOf(1024 * 1024 * 64, info.imageSize.toInt()))
             .let { bf ->
                 bf.order(ByteOrder.LITTLE_ENDIAN)
                 Common.writePaddedFile(bf, kernel.file!!, info.pageSize)
diff --git a/bbootimg/src/main/kotlin/bootimg/v3/BootV3.kt b/bbootimg/src/main/kotlin/bootimg/v3/BootV3.kt
index f5d69da..9f62bed 100644
--- a/bbootimg/src/main/kotlin/bootimg/v3/BootV3.kt
+++ b/bbootimg/src/main/kotlin/bootimg/v3/BootV3.kt
@@ -111,7 +111,8 @@ data class BootV3(
 
         //data
         log.info("Writing data ...")
-        val bf = ByteBuffer.allocate(1024 * 1024 * 96)//assume total SIZE small than 96MB
+        //BootV3 should have correct image size
+        val bf = ByteBuffer.allocate(maxOf(info.imageSize.toInt(), 64 *1024 *1024))
         bf.order(ByteOrder.LITTLE_ENDIAN)
         C.writePaddedFile(bf, this.kernel.file, this.info.pageSize)
         C.writePaddedFile(bf, this.ramdisk.file, this.info.pageSize)
diff --git a/helper/src/test/kotlin/cfig/helper/OpenSslHelperTest.kt b/helper/src/test/kotlin/cfig/helper/OpenSslHelperTest.kt
index ecabca9..bfaa568 100644
--- a/helper/src/test/kotlin/cfig/helper/OpenSslHelperTest.kt
+++ b/helper/src/test/kotlin/cfig/helper/OpenSslHelperTest.kt
@@ -106,5 +106,10 @@ class OpenSslHelperTest {
             this.generate(pk1, crt)
         }
         pfx.toJks().writeTo("platform.jks")
+        File("platform.jks").let {
+            if (it.exists()) {
+                it.delete()
+            }
+        }
     }
 }