commit 4dded613b3aaee016adffd895edf3866426fc22a
author James Hawkins <jhawkins@google.com> Thu Jul 28 11:50:23 2016 -0700
committer James Hawkins <jhawkins@google.com> Thu Jul 28 11:59:22 2016 -0700
tree 6936b5ad2dcc0baa49ba300e89cef14df3c2c32e
parent 44c909d46743f50f67aa4af03ff2588b3b7deb1c

bootstat: Fix a potential unhandled exception for malformed input.

In rare cases the hardware storage on the device may be hosed and return
garbage.  Use ParseInt which handles bad input instead of stoi.

BUG: 29334139
Change-Id: I91aedc169df110bea8097775f73dda11def22311

bootstat/boot_event_record_store.cpp

diff --git a/bootstat/boot_event_record_store.cpp b/bootstat/boot_event_record_store.cpp
index ef4f68e..346eada 100644
--- a/bootstat/boot_event_record_store.cpp
+++ b/bootstat/boot_event_record_store.cpp
@@ -25,6 +25,7 @@
 #include <utility>
 #include <android-base/file.h>
 #include <android-base/logging.h>
+#include <android-base/parseint.h>
 #include "histogram_logger.h"
 #include "uptime_parser.h"
 
@@ -57,8 +58,10 @@
 
   // Ignore existing bootstat records (which do not contain file content).
   if (!content.empty()) {
-    int32_t value = std::stoi(content);
-    bootstat::LogHistogram("bootstat_mtime_matches_content", value == *uptime);
+    int32_t value;
+    if (android::base::ParseInt(content.c_str(), &value)) {
+      bootstat::LogHistogram("bootstat_mtime_matches_content", value == *uptime);
+    }
   }
 
   return true;

bootstat/bootstat.cpp

diff --git a/bootstat/bootstat.cpp b/bootstat/bootstat.cpp
index 7c1b7f3..71a5a39 100644
--- a/bootstat/bootstat.cpp
+++ b/bootstat/bootstat.cpp
@@ -28,6 +28,7 @@
 #include <memory>
 #include <string>
 #include <android-base/logging.h>
+#include <android-base/parseint.h>
 #include <cutils/properties.h>
 #include <log/log.h>
 #include "boot_event_record_store.h"
@@ -56,8 +57,9 @@
   BootEventRecordStore boot_event_store;
   if (!value_str.empty()) {
     int32_t value = 0;
-    value = std::stoi(value_str);
-    boot_event_store.AddBootEventWithValue(event, value);
+    if (android::base::ParseInt(value_str.c_str(), &value)) {
+      boot_event_store.AddBootEventWithValue(event, value);
+    }
   } else {
     boot_event_store.AddBootEvent(event);
   }
@@ -187,7 +189,10 @@
   std::string boot_complete_prefix = "boot_complete";
 
   std::string build_date_str = GetProperty("ro.build.date.utc");
-  int32_t build_date = std::stoi(build_date_str);
+  int32_t build_date;
+  if (!android::base::ParseInt(build_date_str.c_str(), &build_date)) {
+    return std::string();
+  }
 
   BootEventRecordStore boot_event_store;
   BootEventRecordStore::BootEventRecord record;
@@ -223,6 +228,10 @@
   // ota_boot_complete.  The latter signifies that the device is booting after
   // a system update.
   std::string boot_complete_prefix = CalculateBootCompletePrefix();
+  if (boot_complete_prefix.empty()) {
+    // The system is hosed because the build date property could not be read.
+    return;
+  }
 
   // post_decrypt_time_elapsed is only logged on encrypted devices.
   if (boot_event_store.GetBootEvent("post_decrypt_time_elapsed", &record)) {