Fix some 64-bit to 32-bit implicit conversions in chrome_elf.

../../chrome_elf/pe_image_safe/pe_image_safe.cc(76,75):  error: implicit conversion loses integer precision: 'long long' to 'DWORD' (aka 'unsigned long') [-Werror,-Wshorten-64-to-32]
  DWORD optional_header_offset = reinterpret_cast<char*>(optional_header) -
        ~~~~~~~~~~~~~~~~~~~~~~   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^

../../chrome_elf/third_party_dlls/main.cc(77,54):  error: implicit conversion loses integer precision: 'std::vector<unsigned char, std::allocator<unsigned char> >::size_type' (aka 'unsigned long long') to 'DWORD' (aka 'unsigned long') [-Werror,-Wshorten-64-to-32]
                     value_bytes.data(), value_bytes.size());
                                         ~~~~~~~~~~~~^~~~~~

../../chrome_elf/third_party_dlls/logs.cc(127,46):  error: implicit conversion loses integer precision: 'unsigned long long' to 'uint32_t' (aka 'unsigned int') [-Werror,-Wshorten-64-to-32]
                            : kMaxLogEntries - entries_.size();
                              ~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~

../../chrome_elf/third_party_dlls/hook.cc(283,32):  error: implicit conversion loses integer precision: 'ULONG_PTR' (aka 'unsigned long long') to 'DWORD' (aka 'unsigned long') [-Werror,-Wshorten-64-to-32]
  if (!GetDataFromImage(*base, *view_size, &time_date_stamp, &image_size,
       ~~~~~~~~~~~~~~~~        ^~~~~~~~~~

BUG=588506

Change-Id: I82abea7b741de1c56e9bcd1ce8c5bd59357ed20b
Reviewed-on: https://chromium-review.googlesource.com/1184318
Commit-Queue: Will Harris <wfh@chromium.org>
Reviewed-by: Penny MacNeil <pennymac@chromium.org>
Cr-Commit-Position: refs/heads/master@{#585331}

chrome_elf/pe_image_safe/pe_image_safe.cc

@@ -73,8 +73,8 @@ BYTE* PEImageSafe::GetOptionalHeader() {
   PIMAGE_OPTIONAL_HEADER optional_header =
       reinterpret_cast<PIMAGE_OPTIONAL_HEADER>(
           reinterpret_cast<char*>(file_header) + sizeof(IMAGE_FILE_HEADER));
-  DWORD optional_header_offset = reinterpret_cast<char*>(optional_header) -
-                                 reinterpret_cast<char*>(dos_header_);
+  uintptr_t optional_header_offset = reinterpret_cast<char*>(optional_header) -
+                                     reinterpret_cast<char*>(dos_header_);
   if (optional_header_offset + sizeof(IMAGE_OPTIONAL_HEADER::Magic) >
       image_size_) {
     return nullptr;

chrome_elf/third_party_dlls/hook.cc

@@ -4,6 +4,7 @@
 
 #include "chrome_elf/third_party_dlls/hook.h"
 
+#include <limits>
 #include <memory>
 
 #include <assert.h>
@@ -280,8 +281,15 @@ NTSTATUS NewNtMapViewOfSectionImpl(
   std::string image_name;
   std::string section_path;
   std::string section_basename;
-  if (!GetDataFromImage(*base, *view_size, &time_date_stamp, &image_size,
-                        &image_name, &section_path, &section_basename)) {
+
+  assert(*view_size < std::numeric_limits<DWORD>::max());
+  // A memory section can be > 32-bits, but an image/PE in memory can only be <=
+  // 32-bits in size.  That's a limitation of Windows and its interactions with
+  // processors.  No section that appears to be an image (checked above) should
+  // have such a large size.
+  if (!GetDataFromImage(*base, static_cast<DWORD>(*view_size), &time_date_stamp,
+                        &image_size, &image_name, &section_path,
+                        &section_basename)) {
     return ret;
   }
 

chrome_elf/third_party_dlls/logs.cc

@@ -122,9 +122,9 @@ class Log {
   //   logging events should be added via AddEntry().
   void InsertAtEnd(std::vector<LogEntryInternal>::iterator first_element,
                    uint32_t count) {
-    uint32_t elements = (entries_.size() + count <= kMaxLogEntries)
-                            ? count
-                            : kMaxLogEntries - entries_.size();
+    size_t elements = (entries_.size() + count <= kMaxLogEntries)
+                          ? count
+                          : kMaxLogEntries - entries_.size();
     assert(elements <= count);
 
     if (elements)

chrome_elf/third_party_dlls/main.cc

@@ -4,6 +4,8 @@
 
 #include "chrome_elf/third_party_dlls/main.h"
 
+#include <limits>
+
 #include <windows.h>
 
 #include <versionhelpers.h>
@@ -73,8 +75,10 @@ void AddStatusCode(ThirdPartyStatus code) {
 
   AddStatusCodeToBuffer(code, &value_bytes);
 
+  assert(value_bytes.size() < std::numeric_limits<DWORD>::max());
   nt::SetRegKeyValue(key_handle, kStatusCodesRegValue, REG_BINARY,
-                     value_bytes.data(), value_bytes.size());
+                     value_bytes.data(),
+                     static_cast<DWORD>(value_bytes.size()));
   nt::CloseRegKey(key_handle);
 
   return;