From fdd861ef7e3490ab3c0fa9766ca12a5ce2c7376e Mon Sep 17 00:00:00 2001
From: "T.J. Mercier" <tjmercier@google.com>
Date: Fri, 6 Dec 2024 17:52:29 +0000
Subject: [PATCH] debuggerd: Use libprocessgroup to unfreeze

Cgroup v2 paths are owned by libprocessgroup. Those paths can change
based on build flags, so paths generated outside of libprocessgroup may
not always be correct.

Bug: 382693152
Test: adb shell debuggerd -b <pid>
Change-Id: I7e486ab6f4068d0fae1be033a91b9a307f54ed42
---
 debuggerd/Android.bp    |  1 +
 debuggerd/debuggerd.cpp | 11 +++--------
 2 files changed, 4 insertions(+), 8 deletions(-)

diff --git a/debuggerd/Android.bp b/debuggerd/Android.bp
index 3257a2c50..0e62ceb8f 100644
--- a/debuggerd/Android.bp
+++ b/debuggerd/Android.bp
@@ -505,6 +505,7 @@ cc_binary {
         "libbase",
         "libdebuggerd_client",
         "liblog",
+        "libprocessgroup",
         "libprocinfo",
     ],
 
diff --git a/debuggerd/debuggerd.cpp b/debuggerd/debuggerd.cpp
index 0d4b91f75..7a2500c60 100644
--- a/debuggerd/debuggerd.cpp
+++ b/debuggerd/debuggerd.cpp
@@ -23,11 +23,11 @@
 #include <string_view>
 #include <thread>
 
-#include <android-base/file.h>
 #include <android-base/logging.h>
 #include <android-base/parseint.h>
 #include <android-base/unique_fd.h>
 #include <debuggerd/client.h>
+#include <processgroup/processgroup.h>
 #include <procinfo/process.h>
 #include "util.h"
 
@@ -92,13 +92,8 @@ int main(int argc, char* argv[]) {
   }
 
   // unfreeze if pid is frozen.
-  const std::string freeze_file = android::base::StringPrintf(
-      "/sys/fs/cgroup/uid_%d/pid_%d/cgroup.freeze", proc_info.uid, proc_info.pid);
-  if (std::string freeze_status;
-      android::base::ReadFileToString(freeze_file, &freeze_status) && freeze_status[0] == '1') {
-    android::base::WriteStringToFile("0", freeze_file);
-    // we don't restore the frozen state as this is considered a benign change.
-  }
+  SetProcessProfiles(proc_info.uid, proc_info.pid, {"Unfrozen"});
+  // we don't restore the frozen state as this is considered a benign change.
 
   unique_fd output_fd(fcntl(STDOUT_FILENO, F_DUPFD_CLOEXEC, 0));
   if (output_fd.get() == -1) {