Quota: Cap size of requested quota

This change caps size of requested quota as follows:
- Temporary quota is capped at the maximum value of int64
(This is an implementation limitation)
- Persistent quota is capped at 10GB per host


BUG=256288
TEST=content_unittests
NOTRY=true

Review URL: https://codereview.chromium.org/150903003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@249326 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 23 insertions, 2 deletions

diff --git a/webkit/browser/quota/quota_manager.cc b/webkit/browser/quota/quota_manager.cc
index 9e9bc3a..a7e466e 100644
--- a/webkit/browser/quota/quota_manager.cc
+++ b/webkit/browser/quota/quota_manager.cc
@@ -55,6 +55,12 @@ const int64 QuotaManager::kNoLimit = kint64max;
 
 const int QuotaManager::kPerHostTemporaryPortion = 5;  // 20%
 
+// Cap size for per-host persistent quota determined by the histogram.
+// This is a bit lax value because the histogram says nothing about per-host
+// persistent storage usage and we determined by global persistent storage
+// usage that is less than 10GB for almost all users.
+const int64 QuotaManager::kPerHostPersistentQuotaLimit = 10 * 1024 * kMBytes;
+
 const char QuotaManager::kDatabaseName[] = "QuotaManager";
 
 // Preserve kMinimumPreserveForSystem disk space for system book-keeping
@@ -1038,11 +1044,17 @@ void QuotaManager::SetPersistentHostQuota(const std::string& host,
     callback.Run(kQuotaErrorNotSupported, 0);
     return;
   }
+
   if (new_quota < 0) {
     callback.Run(kQuotaErrorInvalidModification, -1);
     return;
   }
 
+  if (kPerHostPersistentQuotaLimit < new_quota) {
+    // Cap the requested size at the per-host quota limit.
+    new_quota = kPerHostPersistentQuotaLimit;
+  }
+
   if (db_disabled_) {
     callback.Run(kQuotaErrorInvalidAccess, -1);
     return;
diff --git a/webkit/browser/quota/quota_manager.h b/webkit/browser/quota/quota_manager.h
index 064d548..a6eeb83 100644
--- a/webkit/browser/quota/quota_manager.h
+++ b/webkit/browser/quota/quota_manager.h
@@ -229,6 +229,8 @@ class WEBKIT_STORAGE_BROWSER_EXPORT QuotaManager
   // utilized by a single host (ie. 5 for 20%).
   static const int kPerHostTemporaryPortion;
 
+  static const int64 kPerHostPersistentQuotaLimit;
+
   static const char kDatabaseName[];
 
   static const int64 kMinimumPreserveForSystem;
diff --git a/webkit/browser/quota/quota_manager_unittest.cc b/webkit/browser/quota/quota_manager_unittest.cc
index 9210537..cc70931 100644
--- a/webkit/browser/quota/quota_manager_unittest.cc
+++ b/webkit/browser/quota/quota_manager_unittest.cc
@@ -962,10 +962,17 @@ TEST_F(QuotaManagerTest, GetAndSetPerststentHostQuota) {
   GetPersistentHostQuota("foo.com");
   SetPersistentHostQuota("foo.com", 200);
   GetPersistentHostQuota("foo.com");
-  SetPersistentHostQuota("foo.com", 300000000000ll);
+  SetPersistentHostQuota("foo.com", QuotaManager::kPerHostPersistentQuotaLimit);
   GetPersistentHostQuota("foo.com");
   base::RunLoop().RunUntilIdle();
-  EXPECT_EQ(300000000000ll, quota());
+  EXPECT_EQ(QuotaManager::kPerHostPersistentQuotaLimit, quota());
+
+  // Persistent quota should be capped at the per-host quota limit.
+  SetPersistentHostQuota("foo.com",
+                         QuotaManager::kPerHostPersistentQuotaLimit + 100);
+  GetPersistentHostQuota("foo.com");
+  base::RunLoop().RunUntilIdle();
+  EXPECT_EQ(QuotaManager::kPerHostPersistentQuotaLimit, quota());
 }
 
 TEST_F(QuotaManagerTest, GetAndSetPersistentUsageAndQuota) {