From d032a92c04c31490ff172d511a60a958f021a311 Mon Sep 17 00:00:00 2001
From: Suren Baghdasaryan <surenb@google.com>
Date: Tue, 12 Feb 2019 18:20:38 -0800
Subject: [PATCH] Fix cgroup support for recovery mode

In recovery mode a separate set of cgroups should be mounted. Add a
cgroups.recovery.json file to describe cgroups mounted during recovery.
Change cgroups descriptor parset to allow cgroups and cgroups2 sections
to be omitted.

Bug: 124270406
Test: "adb reboot sideload; adb devices" shows 'sideload' as expected

Change-Id: Ic32bd2b4612ec8390064f87d4655d1bd1183d741
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
---
 libprocessgroup/cgroup_map.cpp | 32 ++++++++++++++++++--------------
 rootdir/Android.mk             | 10 ++++++++++
 rootdir/cgroups.recovery.json  |  9 +++++++++
 3 files changed, 37 insertions(+), 14 deletions(-)
 create mode 100644 rootdir/cgroups.recovery.json

diff --git a/libprocessgroup/cgroup_map.cpp b/libprocessgroup/cgroup_map.cpp
index cd8ef94a7..d09481181 100644
--- a/libprocessgroup/cgroup_map.cpp
+++ b/libprocessgroup/cgroup_map.cpp
@@ -126,22 +126,26 @@ static bool ReadDescriptors(std::map<std::string, CgroupDescriptor>* descriptors
         return false;
     }
 
-    Json::Value cgroups = root["Cgroups"];
-    for (Json::Value::ArrayIndex i = 0; i < cgroups.size(); ++i) {
-        std::string name = cgroups[i]["Controller"].asString();
-        descriptors->emplace(std::make_pair(
-                name,
-                CgroupDescriptor(1, name, cgroups[i]["Path"].asString(),
-                                 std::strtoul(cgroups[i]["Mode"].asString().c_str(), 0, 8),
-                                 cgroups[i]["UID"].asString(), cgroups[i]["GID"].asString())));
+    if (root.isMember("Cgroups")) {
+        const Json::Value& cgroups = root["Cgroups"];
+        for (Json::Value::ArrayIndex i = 0; i < cgroups.size(); ++i) {
+            std::string name = cgroups[i]["Controller"].asString();
+            descriptors->emplace(std::make_pair(
+                    name,
+                    CgroupDescriptor(1, name, cgroups[i]["Path"].asString(),
+                                     std::strtoul(cgroups[i]["Mode"].asString().c_str(), 0, 8),
+                                     cgroups[i]["UID"].asString(), cgroups[i]["GID"].asString())));
+        }
     }
 
-    Json::Value cgroups2 = root["Cgroups2"];
-    descriptors->emplace(std::make_pair(
-            CGROUPV2_CONTROLLER_NAME,
-            CgroupDescriptor(2, CGROUPV2_CONTROLLER_NAME, cgroups2["Path"].asString(),
-                             std::strtoul(cgroups2["Mode"].asString().c_str(), 0, 8),
-                             cgroups2["UID"].asString(), cgroups2["GID"].asString())));
+    if (root.isMember("Cgroups2")) {
+        const Json::Value& cgroups2 = root["Cgroups2"];
+        descriptors->emplace(std::make_pair(
+                CGROUPV2_CONTROLLER_NAME,
+                CgroupDescriptor(2, CGROUPV2_CONTROLLER_NAME, cgroups2["Path"].asString(),
+                                 std::strtoul(cgroups2["Mode"].asString().c_str(), 0, 8),
+                                 cgroups2["UID"].asString(), cgroups2["GID"].asString())));
+    }
 
     return true;
 }
diff --git a/rootdir/Android.mk b/rootdir/Android.mk
index 123fdd787..b5e5a7125 100644
--- a/rootdir/Android.mk
+++ b/rootdir/Android.mk
@@ -74,6 +74,16 @@ LOCAL_MODULE_PATH := $(TARGET_OUT_ETC)
 
 include $(BUILD_PREBUILT)
 
+#######################################
+# cgroups.json for recovery
+include $(CLEAR_VARS)
+LOCAL_MODULE := cgroups.recovery.json
+LOCAL_SRC_FILES := $(LOCAL_MODULE)
+LOCAL_MODULE_CLASS := ETC
+LOCAL_MODULE_PATH := $(TARGET_RECOVERY_ROOT_OUT)/system/etc
+LOCAL_MODULE_STEM := cgroups.json
+include $(BUILD_PREBUILT)
+
 #######################################
 # task_profiles.json
 include $(CLEAR_VARS)
diff --git a/rootdir/cgroups.recovery.json b/rootdir/cgroups.recovery.json
new file mode 100644
index 000000000..f0bf5fdf1
--- /dev/null
+++ b/rootdir/cgroups.recovery.json
@@ -0,0 +1,9 @@
+{
+  "Cgroups": [
+    {
+      "Controller": "cpuacct",
+      "Path": "/acct",
+      "Mode": "0555"
+    }
+  ]
+}