From a76d9fe46dde4d9f26adc09456e0863d9c2a356c Mon Sep 17 00:00:00 2001
From: Matthieu Gallien <matthieu.gallien@nextcloud.com>
Date: Tue, 4 Apr 2023 14:54:12 +0200
Subject: [PATCH] sort encrypted files by their id to compute checksum

Signed-off-by: Matthieu Gallien <matthieu.gallien@nextcloud.com>
---
 src/libsync/clientsideencryption.cpp | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/libsync/clientsideencryption.cpp b/src/libsync/clientsideencryption.cpp
index ca805835145fb..4dfc3c6d3a7fc 100644
--- a/src/libsync/clientsideencryption.cpp
+++ b/src/libsync/clientsideencryption.cpp
@@ -1722,7 +1722,11 @@ QByteArray FolderMetadata::computeMetadataKeyChecksum(const QByteArray &metadata
     auto hashAlgorithm = QCryptographicHash{QCryptographicHash::Sha256};
 
     hashAlgorithm.addData(_account->e2e()->_mnemonic.remove(' ').toUtf8());
-    for (const auto &singleFile : _files) {
+    auto sortedFiles = _files;
+    std::sort(sortedFiles.begin(), sortedFiles.end(), [] (const auto &first, const auto &second) {
+        return first.encryptedFilename < second.encryptedFilename;
+    });
+    for (const auto &singleFile : sortedFiles) {
         hashAlgorithm.addData(singleFile.encryptedFilename.toUtf8());
     }
     hashAlgorithm.addData(metadataKey);