Linux: fix several bugs in KWallet password store support.

* Don't disable kwallet support if the first site visited
  with a login form has no saved passwords.
* Don't crash when there are certain types of invalid entries
  stored in the wallet that fail to deserialize.
TEST=start with --password-store=detect in KDE and check that the above happens
BUG=49968
Review URL: http://codereview.chromium.org/3048052

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@55535 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 36 insertions, 4 deletions

diff --git a/chrome/browser/password_manager/native_backend_kwallet_x.cc b/chrome/browser/password_manager/native_backend_kwallet_x.cc
index 0cc4bf2..5f07bb8 100644
--- a/chrome/browser/password_manager/native_backend_kwallet_x.cc
+++ b/chrome/browser/password_manager/native_backend_kwallet_x.cc
@@ -208,8 +208,10 @@ bool NativeBackendKWallet::RemoveLoginsCreatedBetween(
                       DBUS_TYPE_G_UCHAR_ARRAY, &byte_array,
                       G_TYPE_INVALID);
 
-    if (CheckError() || !byte_array || !byte_array->len)
+    if (CheckError() || !byte_array ||
+        !CheckSerializedValue(byte_array, *realm)) {
       continue;
+    }
 
     string signon_realm(*realm);
     Pickle pickle(byte_array->data, byte_array->len);
@@ -281,8 +283,12 @@ bool NativeBackendKWallet::GetLoginsList(PasswordFormList* forms,
                     G_TYPE_BOOLEAN, &has_entry,
                     G_TYPE_INVALID);
 
-  if (CheckError() || !has_entry)
+  if (CheckError())
     return false;
+  if (!has_entry) {
+    // This is not an error. There just isn't a matching entry.
+    return true;
+  }
 
   GArray* byte_array = NULL;
   dbus_g_proxy_call(proxy_, "readEntry", &error_,
@@ -294,8 +300,16 @@ bool NativeBackendKWallet::GetLoginsList(PasswordFormList* forms,
                     DBUS_TYPE_G_UCHAR_ARRAY, &byte_array,
                     G_TYPE_INVALID);
 
-  if (CheckError() || !byte_array || !byte_array->len)
+  if (CheckError() || !byte_array)
     return false;
+  if (!CheckSerializedValue(byte_array, signon_realm.c_str())) {
+    // This is weird, but we choose not to call it an error. There's an invalid
+    // entry somehow, but by pretending it just doesn't exist, we make it easier
+    // to repair without having to delete it using kwalletmanager (that is, by
+    // just saving a new password within this realm to overwrite it).
+    g_array_free(byte_array, true);
+    return true;
+  }
 
   Pickle pickle(byte_array->data, byte_array->len);
   DeserializeValue(signon_realm, pickle, forms);
@@ -370,8 +384,10 @@ bool NativeBackendKWallet::GetAllLogins(PasswordFormList* forms,
                       DBUS_TYPE_G_UCHAR_ARRAY, &byte_array,
                       G_TYPE_INVALID);
 
-    if (CheckError() || !byte_array || !byte_array->len)
+    if (CheckError() || !byte_array ||
+        !CheckSerializedValue(byte_array, *realm)) {
       continue;
+    }
 
     Pickle pickle(byte_array->data, byte_array->len);
     DeserializeValue(*realm, pickle, forms);
@@ -463,6 +479,18 @@ void NativeBackendKWallet::SerializeValue(const PasswordFormList& forms,
   }
 }
 
+bool NativeBackendKWallet::CheckSerializedValue(const GArray* byte_array,
+                                                const char* realm) {
+  const Pickle::Header* header =
+      reinterpret_cast<const Pickle::Header*>(byte_array->data);
+  if (byte_array->len < sizeof(*header) ||
+      header->payload_size > byte_array->len - sizeof(*header)) {
+    LOG(WARNING) << "Invalid KWallet entry detected! (realm: " << realm << ")";
+    return false;
+  }
+  return true;
+}
+
 void NativeBackendKWallet::DeserializeValue(const string& signon_realm,
                                             const Pickle& pickle,
                                             PasswordFormList* forms) {
diff --git a/chrome/browser/password_manager/native_backend_kwallet_x.h b/chrome/browser/password_manager/native_backend_kwallet_x.h
index 6c427db..16e3c46 100644
--- a/chrome/browser/password_manager/native_backend_kwallet_x.h
+++ b/chrome/browser/password_manager/native_backend_kwallet_x.h
@@ -92,6 +92,10 @@ class NativeBackendKWallet : public PasswordStoreX::NativeBackend {
   // Serializes a list of PasswordForms to be stored in the wallet.
   static void SerializeValue(const PasswordFormList& forms, Pickle* pickle);
 
+  // Checks a serialized list of PasswordForms for sanity. Returns true if OK.
+  // Note that |realm| is only used for generating a useful warning message.
+  static bool CheckSerializedValue(const GArray* byte_array, const char* realm);
+
   // Deserializes a list of PasswordForms from the wallet.
   static void DeserializeValue(const std::string& signon_realm,
                                const Pickle& pickle,