Prevent 507 Insufficient Storage on 32-bit systems (#40709)

Pasquale Tripodi · web-flow · commit b831feb4b003 · 2023-03-29T09:36:49.000+02:00
* prevent 507 Insufficient Storage on 32bit systems

* add changelog

* improve if-else logic

* retrigger CI
diff --git a/apps/dav/lib/Connector/Sabre/QuotaPlugin.php b/apps/dav/lib/Connector/Sabre/QuotaPlugin.php
@@ -204,13 +204,25 @@ public function checkQuota($path, $length = null, $extraSpace = 0) {
 				$path = \rtrim($parentPath, '/') . '/' . $info['name'];
 			}
 			$freeSpace = $this->getFreeSpace($path);
-			// freeSpace might be false, or an int. Anyway, make sure that availableSpace will be an int.
-			$availableSpace = (int) $freeSpace + $extraSpace;
-			if ($freeSpace !== FileInfo::SPACE_UNKNOWN && $freeSpace !== FileInfo::SPACE_UNLIMITED && (($length > $availableSpace) || ($availableSpace === 0))) {
-				if (isset($chunkHandler)) {
-					$chunkHandler->cleanup();
+			// workaround to guarantee compatibility on 32-bit systems as otherwise this would cause an int overflow on such systems
+			// when $freeSpace is above the max supported value. $freeSpace should be a float so we are using the <= 0.0 comparison
+			if (PHP_INT_SIZE === 4) {
+				$availableSpace = $freeSpace + $extraSpace;
+				if ($freeSpace !== FileInfo::SPACE_UNKNOWN && $freeSpace !== FileInfo::SPACE_UNLIMITED && (($length > $availableSpace) || ($availableSpace <= 0.0))) {
+					if (isset($chunkHandler)) {
+						$chunkHandler->cleanup();
+					}
+					throw new InsufficientStorage();
+				}
+			} else {
+				// freeSpace might be false, or an int. Anyway, make sure that availableSpace will be an int.
+				$availableSpace = (int) $freeSpace + $extraSpace;
+				if ($freeSpace !== FileInfo::SPACE_UNKNOWN && $freeSpace !== FileInfo::SPACE_UNLIMITED && (($length > $availableSpace) || ($availableSpace === 0))) {
+					if (isset($chunkHandler)) {
+						$chunkHandler->cleanup();
+					}
+					throw new InsufficientStorage();
 				}
-				throw new InsufficientStorage();
 			}
 		}
 		return true;
diff --git a/changelog/unreleased/40709 b/changelog/unreleased/40709
@@ -0,0 +1,3 @@
+Bugfix: Prevent 507 Insufficient Storage on 32-bit systems
+
+With the introduction of https://github.com/owncloud/core/pull/40567 compatibility to 32-bit systems broke as we are now casting $freeSpace to int and this caused an integer overflow on such systems when the free space was above the max supported value. We added therefore an additional check for 32-bit systems in QuotaPlugin.php.

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,3 @@`
	`1`	`+Bugfix: Prevent 507 Insufficient Storage on 32-bit systems`
	`2`	`+`
	`3`	`+With the introduction of https://github.com/owncloud/core/pull/40567 compatibility to 32-bit systems broke as we are now casting $freeSpace to int and this caused an integer overflow on such systems when the free space was above the max supported value. We added therefore an additional check for 32-bit systems in QuotaPlugin.php.`