wsd: re-create the jail directory when mounting fails

This guarantees that the jail directory is always
created, especially in case mounting fails and
we cleanup and fallback.

Also, move the directory creation and setting
the perms into a helper, and reuse.

Change-Id: If6e9ef86afa5107638aa27050554e94c0af22b6e
Signed-off-by: Ashod Nakashian <ashod.nakashian@collabora.co.uk>

common/JailUtil.cpp

@@ -206,11 +206,18 @@ void cleanupJails(const std::string& root)
         LOG_WRN("Jails root directory [" << root << "] is not empty. Will not remove it.");
 }
 
+void createJailPath(const std::string& path)
+{
+    LOG_INF("Creating jail path (if missing): " << path);
+    Poco::File(path).createDirectories();
+    chmod(path.c_str(), S_IXUSR | S_IWUSR | S_IRUSR);
+}
+
 void setupChildRoot(bool bindMount, const std::string& childRoot, const std::string& sysTemplate)
 {
     // Start with a clean slate.
     cleanupJails(childRoot);
-    Poco::File(childRoot + CHILDROOT_TMP_INCOMING_PATH).createDirectories();
+    createJailPath(childRoot + CHILDROOT_TMP_INCOMING_PATH);
 
     disableBindMounting(); // Clear to avoid surprises.
 

common/JailUtil.hpp

@@ -42,6 +42,9 @@ void removeJail(const std::string& root);
 /// Remove all jails.
 void cleanupJails(const std::string& jailRoot);
 
+/// Creates the jail directory path recursively.
+void createJailPath(const std::string& path);
+
 /// Setup the Child-Root directory.
 void setupChildRoot(bool bindMount, const std::string& jailRoot, const std::string& sysTemplate);
 

kit/Kit.cpp

@@ -2627,9 +2627,7 @@ void lokit_main(
 #if !MOBILEAPP
         const Path jailPath = Path::forDirectory(childRoot + '/' + jailId);
         const std::string jailPathStr = jailPath.toString();
-        LOG_INF("Jail path: " << jailPathStr);
-        File(jailPath).createDirectories();
-        chmod(jailPathStr.c_str(), S_IXUSR | S_IWUSR | S_IRUSR);
+        JailUtil::createJailPath(jailPathStr);
 
         if (!ChildSession::NoCapsForKit)
         {
@@ -2658,7 +2656,7 @@ void lokit_main(
 
                 // Mount loTemplate inside it.
                 LOG_INF("Mounting " << loTemplate << " -> " << loJailDestPath);
-                Poco::File(loJailDestPath).createDirectories();
+                JailUtil::createJailPath(loJailDestPath);
                 if (!JailUtil::bind(loTemplate, loJailDestPath)
                     || !JailUtil::remountReadonly(loTemplate, loJailDestPath))
                 {
@@ -2707,6 +2705,9 @@ void lokit_main(
                 LOG_INF("Mounting is disabled, will link/copy " << sysTemplate << " -> "
                                                                 << jailPathStr);
 
+                // Make sure we have the jail directory.
+                JailUtil::createJailPath(jailPathStr);
+
                 // Create a file to mark this a copied jail.
                 JailUtil::markJailCopied(jailPathStr);