diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/dfs/DfsPackFile.java b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/dfs/DfsPackFile.java
index b1e95520c..96ca690c1 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/dfs/DfsPackFile.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/dfs/DfsPackFile.java
@@ -607,8 +607,15 @@ private IOException packfileIsTruncated() {
 
 	private void readFully(long position, byte[] dstbuf, int dstoff, int cnt,
 			DfsReader ctx) throws IOException {
-		if (ctx.copy(this, position, dstbuf, dstoff, cnt) != cnt)
-			throw new EOFException();
+		while (cnt > 0) {
+			int copied = ctx.copy(this, position, dstbuf, dstoff, cnt);
+			if (copied == 0) {
+				throw new EOFException();
+			}
+			position += copied;
+			dstoff += copied;
+			cnt -= copied;
+		}
 	}
 
 	ObjectLoader load(DfsReader ctx, long pos)