From 34ebafb8b65cef86fdda9bef64bc33e968e0d319 Mon Sep 17 00:00:00 2001
From: Michael Eischer <michael.eischer@fau.de>
Date: Fri, 20 Aug 2021 16:16:45 +0200
Subject: [PATCH] repository: don't crash if blob size is too short

---
 internal/repository/repository.go | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/internal/repository/repository.go b/internal/repository/repository.go
index b43c3cec9..472c4cd15 100644
--- a/internal/repository/repository.go
+++ b/internal/repository/repository.go
@@ -801,6 +801,11 @@ func StreamPack(ctx context.Context, beLoad BackendLoadFn, key *crypto.Key, pack
 			}
 			currentBlobEnd = entry.Offset + entry.Length
 
+			if int(entry.Length) <= key.NonceSize() {
+				debug.Log("%v", blobs)
+				return errors.Errorf("invalid blob length %v", entry)
+			}
+
 			// decryption errors are likely permanent, give the caller a chance to skip them
 			nonce, ciphertext := buf[:key.NonceSize()], buf[key.NonceSize():]
 			plaintext, err := key.Open(ciphertext[:0], nonce, ciphertext, nil)