diff --git a/core/spring-boot/src/main/java/org/springframework/boot/logging/logback/SpringBootJoranConfigurator.java b/core/spring-boot/src/main/java/org/springframework/boot/logging/logback/SpringBootJoranConfigurator.java
index ac1d5cc0bd3..d344da6e501 100644
--- a/core/spring-boot/src/main/java/org/springframework/boot/logging/logback/SpringBootJoranConfigurator.java
+++ b/core/spring-boot/src/main/java/org/springframework/boot/logging/logback/SpringBootJoranConfigurator.java
@@ -442,7 +442,7 @@ class SpringBootJoranConfigurator extends JoranConfigurator {
 			if (file.exists()) {
 				InputStreamSource content = file.getContent();
 				Assert.state(content != null, "Unable to get file content");
-				byte[] existingContent = content.getInputStream().readAllBytes();
+				byte[] existingContent = toByteArray(content);
 				if (!Arrays.equals(this.newContent, existingContent)) {
 					throw new IllegalStateException(
 							"Logging configuration differs from the configuration that has already been written. "
@@ -454,6 +454,12 @@ class SpringBootJoranConfigurator extends JoranConfigurator {
 			}
 		}
 
+		private byte[] toByteArray(InputStreamSource content) throws IOException {
+			try (InputStream inputStream = content.getInputStream()) {
+				return inputStream.readAllBytes();
+			}
+		}
+
 	}
 
 }