From 9b73e1465d6d5c6acc3c06f551569348d3dd9388 Mon Sep 17 00:00:00 2001
From: Lukasz Pawelczyk <l.pawelczyk@samsung.com>
Date: Wed, 16 Aug 2017 17:26:06 +0200
Subject: [PATCH] InternalEncryption: make umount logic more error proof

Don't umount if the device is not already mounted.
Try to umount if the device is mounted more then once (bind).

Change-Id: I0656146225fb0df429a4da1af743bc1d1cbdb9f9
---
 server/internal-encryption.cpp | 126 +++++++++++++++++++++++----------
 1 file changed, 87 insertions(+), 39 deletions(-)

diff --git a/server/internal-encryption.cpp b/server/internal-encryption.cpp
index 7704078..11a6c1a 100644
--- a/server/internal-encryption.cpp
+++ b/server/internal-encryption.cpp
@@ -21,6 +21,10 @@
 #include <unistd.h>
 #include <sys/mount.h>
 #include <sys/reboot.h>
+#include <stdio.h>
+#include <mntent.h>
+#include <limits.h>
+#include <stdlib.h>
 
 #include <vconf.h>
 #include <tzplatform_config.h>
@@ -61,6 +65,56 @@ namespace ode {
 
 namespace {
 
+std::string findDevPath()
+{
+	std::string source = INTERNAL_DEV_PATH "/" INTERNAL_DEV_NAME;
+	try {
+		runtime::DirectoryIterator iter(INTERNAL_DEV_PATH), end;
+
+		while (iter != end) {
+			const std::string& path = (*iter).getPath();
+			std::string name = path.substr(path.rfind('/') + 1);
+			std::string upper;
+			upper.reserve(name.size());
+			for (char c : name) {
+				upper += std::toupper(c);
+			}
+			if (upper == INTERNAL_DEV_NAME) {
+				source = path;
+				break;
+			}
+			++iter;
+		}
+	} catch (runtime::Exception &e) {}
+
+	char *dev = ::realpath(source.c_str(), NULL);
+	if (dev == NULL) {
+		throw runtime::Exception("Failed to find device path.");
+	}
+
+	std::string devPath(dev);
+	free(dev);
+
+	return devPath;
+}
+
+std::string findMntPath(const std::string &devPath)
+{
+	std::string ret;
+
+	FILE* mtab = ::setmntent("/etc/mtab", "r");
+	struct mntent* entry = NULL;
+	while ((entry = ::getmntent(mtab)) != NULL) {
+		if (devPath == entry->mnt_fsname) {
+			ret = entry->mnt_dir;
+			break;
+		}
+	}
+	::endmntent(mtab);
+
+	return ret;
+}
+
 std::unique_ptr<INTERNAL_ENGINE> engine;
 KeyManager::data mountKey;
 
@@ -215,25 +269,7 @@ InternalEncryption::InternalEncryption(ODEControlContext& ctx) :
 
 	context.createNotification("InternalEncryption::mount");
 
-	std::string source = INTERNAL_DEV_PATH "/" INTERNAL_DEV_NAME;
-	try {
-		runtime::DirectoryIterator iter(INTERNAL_DEV_PATH), end;
-
-		while (iter != end) {
-			const std::string& path = (*iter).getPath();
-			std::string name = path.substr(path.rfind('/') + 1);
-			std::string upper;
-			upper.reserve(name.size());
-			for (char c : name) {
-				upper += std::toupper(c);
-			}
-			if (upper == INTERNAL_DEV_NAME) {
-				source = path;
-				break;
-			}
-			++iter;
-		}
-	} catch (runtime::Exception &e) {}
+	std::string source = findDevPath();
 
 	engine.reset(new INTERNAL_ENGINE(
 		source, INTERNAL_PATH,
@@ -329,18 +365,27 @@ int InternalEncryption::encrypt(const std::string& password, unsigned int option
 	KeyManager::data MasterKey = keyManager.getMasterKey(pwData);
 	auto encryptWorker = [MasterKey, options, this]() {
 		try {
-			INFO(SINK, "Close all known systemd services that might be using internal storage...");
-			stopKnownSystemdServices();
-			INFO(SINK, "Close all processes using internal storage...");
-			stopDependedSystemdServices();
-			INFO(SINK, "Umount internal storage...");
-			while (::umount(INTERNAL_PATH) == -1) {
-				if (errno != EBUSY) {
-					throw runtime::Exception("Umount error - " + std::to_string(errno));
-				}
+			std::string source = engine->getSource();
+			std::string mntPath = findMntPath(source);
+
+			if (!mntPath.empty()) {
+				INFO(SINK, "Close all known systemd services that might be using internal storage...");
+				stopKnownSystemdServices();
+				INFO(SINK, "Close all processes using internal storage...");
 				stopDependedSystemdServices();
 			}
 
+			while (!mntPath.empty()) {
+				INFO(SINK, "Umount internal storage...");
+				while (::umount(mntPath.c_str()) == -1) {
+					if (errno != EBUSY) {
+						throw runtime::Exception("Umount error - " + std::to_string(errno));
+					}
+					stopDependedSystemdServices();
+				}
+				mntPath = findMntPath(source);
+			}
+
 			showProgressUI("Encrypting");
 
 			INFO(SINK, "Encryption started...");
@@ -382,17 +427,20 @@ int InternalEncryption::decrypt(const std::string& password)
 	KeyManager::data MasterKey = keyManager.getMasterKey(pwData);
 	auto decryptWorker = [MasterKey, this]() {
 		try {
-			INFO(SINK, "Close all known systemd services that might be using internal storage...");
-			stopKnownSystemdServices();
-			INFO(SINK, "Close all processes using internal storage...");
-			stopDependedSystemdServices();
-			INFO(SINK, "Umount internal storage...");
-			while (1) {
-				try {
-					engine->umount();
-					break;
-				} catch (runtime::Exception& e) {
-					stopDependedSystemdServices();
+			if (engine->isMounted()) {
+				INFO(SINK, "Close all known systemd services that might be using internal storage...");
+				stopKnownSystemdServices();
+				INFO(SINK, "Close all processes using internal storage...");
+				stopDependedSystemdServices();
+
+				INFO(SINK, "Umount internal storage...");
+				while (1) {
+					try {
+						engine->umount();
+						break;
+					} catch (runtime::Exception& e) {
+						stopDependedSystemdServices();
+					}
 				}
 			}
 
-- 
2.34.1