diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/util/io/TeeInputStream.java b/org.eclipse.jgit/src/org/eclipse/jgit/util/io/TeeInputStream.java
index 9d036595f..16ed9c6eb 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/util/io/TeeInputStream.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/util/io/TeeInputStream.java
@@ -110,7 +110,7 @@ public int read(byte[] b, int off, int len) throws IOException {
 
 		int n = src.read(b, off, len);
 		if (0 < n)
-			dst.write(b, off, len);
+			dst.write(b, off, n);
 		return n;
 	}