From 57df4d8629a3184cfbbd1a8888805e0566eb9cdd Mon Sep 17 00:00:00 2001
From: Kent Delante <kent@delante.me>
Date: Thu, 16 Jul 2026 16:38:24 +0800
Subject: [PATCH 1/2] fix(files): preserve encryptedVersion when copying cache
 entries

Cache::copyFromCache() rebuilt the target's cache row via
cacheEntryToArray(), which only carried over a boolean `encrypted`
flag and dropped the real `encryptedVersion` count. Since
View::copy() unconditionally calls copyFromCache() after the storage
copy completes, this silently overwrote the correct encryptedVersion
that Encryption::updateEncryptedVersion() had just set, collapsing it
back to 0/1 on every copy of a file whose encryptedVersion was above 1.

cacheEntryToArray() now includes the source entry's encryptedVersion
when it is encrypted. The existing encrypted-to-non-encrypted-storage
override in copyFromCache() also clears encryptedVersion alongside
`encrypted`, since normalizeData() prefers encryptedVersion over
`encrypted` when both are present in the update data.

Signed-off-by: Kent Delante <kent@delante.me>
Assisted-by: ClaudeCode:claude-sonnet-5
---
 lib/private/Files/Cache/Cache.php | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/lib/private/Files/Cache/Cache.php b/lib/private/Files/Cache/Cache.php
index ae5bbe011c9d6..67156893c3fd2 100644
--- a/lib/private/Files/Cache/Cache.php
+++ b/lib/private/Files/Cache/Cache.php
@@ -1166,6 +1166,9 @@ public function copyFromCache(ICache $sourceCache, ICacheEntry $sourceEntry, str
 		// when moving from an encrypted storage to a non-encrypted storage remove the `encrypted` mark
 		if ($sourceCache instanceof Cache && $sourceCache->hasEncryptionWrapper() && !$this->hasEncryptionWrapper()) {
 			$data['encrypted'] = 0;
+			// normalizeData() prefers 'encryptedVersion' over 'encrypted' when both are
+			// set, so it has to be cleared too or the mark above gets ignored
+			unset($data['encryptedVersion']);
 		}
 
 		$fileId = $this->put($targetPath, $data);
@@ -1199,6 +1202,11 @@ private function cacheEntryToArray(ICacheEntry $entry): array {
 		if ($entry instanceof CacheEntry && isset($entry['scan_permissions'])) {
 			$data['permissions'] = $entry['scan_permissions'];
 		}
+
+		if ($entry->isEncrypted() && isset($entry['encryptedVersion'])) {
+			$data['encryptedVersion'] = $entry['encryptedVersion'];
+		}
+
 		return $data;
 	}
 

From eb4df90489ea7fbf36ca02ea5c6efb479c01cbd2 Mon Sep 17 00:00:00 2001
From: Kent Delante <kent@delante.me>
Date: Thu, 16 Jul 2026 16:54:47 +0800
Subject: [PATCH 2/2] test: add tests for encryptedVersion cache entry
 preservation

Signed-off-by: Kent Delante <kent@delante.me>
Assisted-by: ClaudeCode:claude-sonnet-5
---
 tests/lib/Files/Cache/CacheTest.php | 43 +++++++++++++++++++++++++++++
 1 file changed, 43 insertions(+)

diff --git a/tests/lib/Files/Cache/CacheTest.php b/tests/lib/Files/Cache/CacheTest.php
index 821b371294af7..6c9f67f07a0f4 100644
--- a/tests/lib/Files/Cache/CacheTest.php
+++ b/tests/lib/Files/Cache/CacheTest.php
@@ -500,6 +500,49 @@ public function testMoveFromCache() {
 		$this->assertTrue($this->cache->inCache('targetfolder/sub'));
 	}
 
+	public function testCopyFromCachePreservesEncryptedVersion(): void {
+		$data = [
+			'size' => 100, 'mtime' => 50, 'mimetype' => 'foo/bar',
+			'encrypted' => true, 'encryptedVersion' => 3,
+		];
+		$this->cache->put('source', $data);
+		$sourceEntry = $this->cache->get('source');
+		$this->assertSame(3, $sourceEntry['encryptedVersion']);
+
+		$this->cache->copyFromCache($this->cache, $sourceEntry, 'target');
+
+		$targetEntry = $this->cache->get('target');
+		$this->assertTrue($targetEntry->isEncrypted());
+		$this->assertSame(3, $targetEntry['encryptedVersion']);
+	}
+
+	public function testCopyFromCacheClearsEncryptedVersionWhenCopyingToNonEncryptedStorage(): void {
+		$data = [
+			'size' => 100, 'mtime' => 50, 'mimetype' => 'foo/bar',
+			'encrypted' => true, 'encryptedVersion' => 3,
+		];
+		$this->cache2->put('source', $data);
+		$sourceEntry = $this->cache2->get('source');
+
+		$sourceCache = $this->getMockBuilder(Cache::class)
+			->setConstructorArgs([$this->storage2])
+			->onlyMethods(['hasEncryptionWrapper'])
+			->getMock();
+		$sourceCache->method('hasEncryptionWrapper')->willReturn(true);
+
+		$targetCache = $this->getMockBuilder(Cache::class)
+			->setConstructorArgs([$this->storage])
+			->onlyMethods(['hasEncryptionWrapper'])
+			->getMock();
+		$targetCache->method('hasEncryptionWrapper')->willReturn(false);
+
+		$targetCache->copyFromCache($sourceCache, $sourceEntry, 'target');
+
+		$targetEntry = $targetCache->get('target');
+		$this->assertFalse($targetEntry['encrypted']);
+		$this->assertSame(0, $targetEntry['encryptedVersion']);
+	}
+
 	public function testGetIncomplete() {
 		$file1 = 'folder1';
 		$file2 = 'folder2';