Skip to content

Commit

Permalink
deps: backport 3a9bfec from v8 upstream
Browse files Browse the repository at this point in the history
Original commit message:

  Fix overflow issue in Zone::New

  When requesting a large allocation near the end of the address space,
  the computation could overflow and erroneously *not* grow the Zone
  as required.

	BUG=chromium:606115
	LOG=y

  Review-Url: https://codereview.chromium.org/1930873002
  Cr-Commit-Position: refs/heads/master@{#35903}

PR-URL: nodejs-private/node-private#38
Reviewed-By: Fedor Indutny <fedor.indutny@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Myles Borins <myles.borins@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
  • Loading branch information
bnoordhuis authored and Myles Borins committed Jun 6, 2016
1 parent e2ccf62 commit 134c3b3
Show file tree
Hide file tree
Showing 2 changed files with 9 additions and 3 deletions.
2 changes: 1 addition & 1 deletion deps/v8/include/v8-version.h
Original file line number Diff line number Diff line change
Expand Up @@ -11,7 +11,7 @@
#define V8_MAJOR_VERSION 4
#define V8_MINOR_VERSION 5
#define V8_BUILD_NUMBER 103
#define V8_PATCH_LEVEL 35
#define V8_PATCH_LEVEL 36

// Use 1 for candidates and 0 otherwise.
// (Boolean macro values are not supported by all preprocessors.)
Expand Down
10 changes: 8 additions & 2 deletions deps/v8/src/zone.cc
Original file line number Diff line number Diff line change
Expand Up @@ -105,7 +105,10 @@ void* Zone::New(size_t size) {
Address result = position_;

const size_t size_with_redzone = size + kASanRedzoneBytes;
if (limit_ < position_ + size_with_redzone) {
const uintptr_t limit = reinterpret_cast<uintptr_t>(limit_);
const uintptr_t position = reinterpret_cast<uintptr_t>(position_);
// position_ > limit_ can be true after the alignment correction above.
if (limit < position || size_with_redzone > limit - position) {
result = NewExpand(size_with_redzone);
} else {
position_ += size_with_redzone;
Expand Down Expand Up @@ -222,7 +225,10 @@ Address Zone::NewExpand(size_t size) {
// Make sure the requested size is already properly aligned and that
// there isn't enough room in the Zone to satisfy the request.
DCHECK_EQ(size, RoundDown(size, kAlignment));
DCHECK_LT(limit_, position_ + size);
DCHECK(limit_ < position_ ||
reinterpret_cast<uintptr_t>(limit_) -
reinterpret_cast<uintptr_t>(position_) <
size);

// Compute the new segment size. We use a 'high water mark'
// strategy, where we increase the segment size every time we expand
Expand Down

0 comments on commit 134c3b3

Please sign in to comment.