commit 26d87f53b5c1e7169455fdaf8e2305e3b9fcbb54
author Henrique Nakashima <hnakashima@chromium.org> Tue Sep 26 16:44:20 2017 -0400
committer Chromium commit bot <commit-bot@chromium.org> Tue Sep 26 21:19:43 2017 +0000
tree dd5fc1b4ff4b9a42e28f9cd0a14bad9aa3be9e0f
parent 6f7bd9fdc4f4d7f21e468c47ee3e5616330541a6

[Merge M62] Fix UAF after destroying a widget during OnBeforeKeyStroke().

> Bug: chromium:766957
> Change-Id: I61b282059fb4fc2c8ba6dafc502f030f31dd324d
> Reviewed-on: https://pdfium-review.googlesource.com/14710
> Commit-Queue: Henrique Nakashima <hnakashima@chromium.org>
> Reviewed-by: Tom Sepez <tsepez@chromium.org>

Change-Id: I1dae26d28dd5720b57d8696a77fe3b514646edcd
Reviewed-on: https://pdfium-review.googlesource.com/14835
Commit-Queue: Henrique Nakashima <hnakashima@chromium.org>
Commit-Queue: dsinclair <dsinclair@chromium.org>
Reviewed-by: dsinclair <dsinclair@chromium.org>

fpdfsdk/pwl/cpwl_edit.cpp

diff --git a/fpdfsdk/pwl/cpwl_edit.cpp b/fpdfsdk/pwl/cpwl_edit.cpp
index 4558e43..0a2aff6 100644
--- a/fpdfsdk/pwl/cpwl_edit.cpp
+++ b/fpdfsdk/pwl/cpwl_edit.cpp
@@ -473,11 +473,17 @@
       if (nSelStart == nSelEnd)
         nSelEnd = nSelStart + 1;
 
+      CPWL_Wnd::ObservedPtr thisObserved(this);
+
       bool bRC;
       bool bExit;
       std::tie(bRC, bExit) = m_pFillerNotify->OnBeforeKeyStroke(
           GetAttachedData(), strChange, strChangeEx, nSelStart, nSelEnd, true,
           nFlag);
+
+      if (!thisObserved)
+        return false;
+
       if (!bRC)
         return false;
       if (bExit)
@@ -550,10 +556,15 @@
           break;
       }
 
+      CPWL_Wnd::ObservedPtr thisObserved(this);
+
       CFX_WideString strChangeEx;
       std::tie(bRC, bExit) = m_pFillerNotify->OnBeforeKeyStroke(
           GetAttachedData(), swChange, strChangeEx, nSelStart, nSelEnd, true,
           nFlag);
+
+      if (!thisObserved)
+        return false;
     }
   }
 

fpdfsdk/pwl/cpwl_list_box.cpp

diff --git a/fpdfsdk/pwl/cpwl_list_box.cpp b/fpdfsdk/pwl/cpwl_list_box.cpp
index a9c553e..6cbf73e 100644
--- a/fpdfsdk/pwl/cpwl_list_box.cpp
+++ b/fpdfsdk/pwl/cpwl_list_box.cpp
@@ -260,6 +260,8 @@
   if (!m_pFillerNotify)
     return false;
 
+  CPWL_Wnd::ObservedPtr thisObserved(this);
+
   CFX_WideString swChange = GetText();
   CFX_WideString strChangeEx;
   int nSelStart = 0;
@@ -269,6 +271,10 @@
   std::tie(bRC, bExit) = m_pFillerNotify->OnBeforeKeyStroke(
       GetAttachedData(), swChange, strChangeEx, nSelStart, nSelEnd, bKeyDown,
       nFlag);
+
+  if (!thisObserved)
+    return false;
+
   return bExit;
 }