From 6b0874203d3dc77bf4ff274add5a7d7844e791b8 Mon Sep 17 00:00:00 2001
From: Robin Appelman <icewind@owncloud.com>
Date: Wed, 3 Jun 2015 16:23:43 +0200
Subject: [PATCH 1/2] add proper locking to file_put_contents when using
 streams

---
 lib/private/files/view.php | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/lib/private/files/view.php b/lib/private/files/view.php
index b98842f5eb7..1b492213053 100644
--- a/lib/private/files/view.php
+++ b/lib/private/files/view.php
@@ -535,25 +535,37 @@ class View {
 			) {
 				$path = $this->getRelativePath($absolutePath);
 
+				$this->lockFile($path, ILockingProvider::LOCK_SHARED);
+
 				$exists = $this->file_exists($path);
 				$run = true;
 				if ($this->shouldEmitHooks($path)) {
 					$this->emit_file_hooks_pre($exists, $path, $run);
 				}
 				if (!$run) {
+					$this->unlockFile($path, ILockingProvider::LOCK_SHARED);
 					return false;
 				}
-				$target = $this->fopen($path, 'w');
+
+				$this->changeLock($path, ILockingProvider::LOCK_EXCLUSIVE);
+
+				/** @var \OC\Files\Storage\Storage $storage */
+				list($storage, $internalPath) = $this->resolvePath($path);
+				$target = $storage->fopen($internalPath, 'w');
 				if ($target) {
-					list ($count, $result) = \OC_Helper::streamCopy($data, $target);
+					list (, $result) = \OC_Helper::streamCopy($data, $target);
 					fclose($target);
 					fclose($data);
 					$this->updater->update($path);
+
+					$this->unlockFile($path, ILockingProvider::LOCK_EXCLUSIVE);
+
 					if ($this->shouldEmitHooks($path) && $result !== false) {
 						$this->emit_file_hooks_post($exists, $path);
 					}
 					return $result;
 				} else {
+					$this->unlockFile($path, ILockingProvider::LOCK_EXCLUSIVE);
 					return false;
 				}
 			} else {

From bcf13aff6f9082f87930068ecd9560612e36fc6a Mon Sep 17 00:00:00 2001
From: Robin Appelman <icewind@owncloud.com>
Date: Wed, 3 Jun 2015 16:51:21 +0200
Subject: [PATCH 2/2] change lock back to shared before updating the cache

---
 lib/private/files/view.php | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/lib/private/files/view.php b/lib/private/files/view.php
index 1b492213053..48fec01f171 100644
--- a/lib/private/files/view.php
+++ b/lib/private/files/view.php
@@ -556,9 +556,12 @@ class View {
 					list (, $result) = \OC_Helper::streamCopy($data, $target);
 					fclose($target);
 					fclose($data);
+
+					$this->changeLock($path, ILockingProvider::LOCK_SHARED);
+
 					$this->updater->update($path);
 
-					$this->unlockFile($path, ILockingProvider::LOCK_EXCLUSIVE);
+					$this->unlockFile($path, ILockingProvider::LOCK_SHARED);
 
 					if ($this->shouldEmitHooks($path) && $result !== false) {
 						$this->emit_file_hooks_post($exists, $path);