This is a serious security regression. If you are not able to fix this quickly, please revert the change that introduced it.

If this doesn't affect a release branch, or has not been properly classified for severity, please update the Security_Impact or Security_Severity labels, and remove the ReleaseBlock label. To disable this altogether, apply ReleaseBlock-NA.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

Automatically assigning owner based on suspected regression changelist https://chromium.googlesource.com/v8/v8/+/17001a05c8ca848b75f3c667192bcf99bdcd42fd ([wasm] Introduce instance types for WebAssembly.* objects.).

If this is incorrect, please remove the owner and apply the Test-Predator-Wrong-CLs label.

titzer: Uh oh! This issue still open and hasn't been updated in the last 15 days. This is a serious vulnerability, and we want to ensure that there's progress. Could you please leave an update with the current status and any potential blockers?

If you're not the right owner for this issue, could you please remove yourself as soon as possible or help us find the right one?

If the issue is fixed or you can't reproduce it, please close the bug. If you've started working on a fix, please set the status to Started.

Thanks for your time! To disable nags, add the Disable-Nags label.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

The following revision refers to this bug:
  https://chromium.googlesource.com/v8/v8.git/+/0957bd96ac9ef98ef8edd8a3d754963c1b925ce6

commit 0957bd96ac9ef98ef8edd8a3d754963c1b925ce6
Author: Ben L. Titzer <titzer@chromium.org>
Date: Mon Oct 23 13:02:09 2017

[wasm] Fix subclassing for WebAssembly.* types.

R=rossberg@chromium.org

Bug:  chromium:772636 
Change-Id: I885f8657eb755953be17d7bf32aef2629092b9c2
Reviewed-on: https://chromium-review.googlesource.com/733086
Reviewed-by: Andreas Rossberg <rossberg@chromium.org>
Commit-Queue: Ben Titzer <titzer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48830}
[modify] https://crrev.com/0957bd96ac9ef98ef8edd8a3d754963c1b925ce6/src/objects.cc
[modify] https://crrev.com/0957bd96ac9ef98ef8edd8a3d754963c1b925ce6/test/mjsunit/wasm/js-api.js

ClusterFuzz has detected this issue as fixed in range 48829:48830.

Detailed report: https://clusterfuzz.com/testcase?key=6287478012248064

Fuzzer: ochang_js_fuzzer
Job Type: linux_asan_d8_dbg
Platform Id: linux

Crash Type: DCHECK failure
Crash Address: 
Crash State:
  CanSubclassHaveInobjectProperties(instance_type) in objects.cc
  v8::internal::JSFunction::GetDerivedMap
  v8::internal::JSObject::New
  
Sanitizer: address (ASAN)

Regressed: https://clusterfuzz.com/revisions?job=linux_asan_d8_dbg&range=46474:46475
Fixed: https://clusterfuzz.com/revisions?job=linux_asan_d8_dbg&range=48829:48830

Reproducer Testcase: https://clusterfuzz.com/download?testcase_id=6287478012248064

See https://github.com/google/clusterfuzz-tools for more information.

If you suspect that the result above is incorrect, try re-doing that job on the test case report page.

ClusterFuzz testcase 6287478012248064 is verified as fixed, so closing issue as verified.

If this is incorrect, please add ClusterFuzz-Wrong label and re-open the issue.

This bug requires manual review: M63 has already been promoted to the beta branch, so this requires manual review
Please contact the milestone owner if you have questions.
Owners: cmasso@(Android), cmasso@(iOS), gkihumba@(ChromeOS), govind@(Desktop)

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

+awhalley@ (Security TPM) for M63 merge review

@govind - good for 63

Approving merge to M63 branch 3239 based on comment #15. Please merge before 4:00 PM PT, today (Monday) so we can pick it up for this week Beta release. Thank you.

The following revision refers to this bug:
  https://chromium.googlesource.com/v8/v8.git/+/3b1b11130c9e9df7f82444b37a03081678c7bbb6

commit 3b1b11130c9e9df7f82444b37a03081678c7bbb6
Author: Ben L. Titzer <titzer@chromium.org>
Date: Mon Oct 30 16:08:20 2017

Merged: [wasm] Fix subclassing for WebAssembly.* types.

R=​rossberg@chromium.org

NOTRY=true
NOPRESUBMIT=true
NOTREECHECKS=true

Bug:  chromium:772636 
Change-Id: I885f8657eb755953be17d7bf32aef2629092b9c2
Reviewed-on: https://chromium-review.googlesource.com/733086
Reviewed-by: Andreas Rossberg <rossberg@chromium.org>
Commit-Queue: Ben Titzer <titzer@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#48830}(cherry picked from commit 0957bd96ac9ef98ef8edd8a3d754963c1b925ce6)
Reviewed-on: https://chromium-review.googlesource.com/743902
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/branch-heads/6.3@{#46}
Cr-Branched-From: 094a7c93dcdcd921de3883ba4674b7e1a0feffbe-refs/heads/6.3.292@{#1}
Cr-Branched-From: 18b8fbb528a8021e04a029e06eafee50b918bce0-refs/heads/master@{#48432}
[modify] https://crrev.com/3b1b11130c9e9df7f82444b37a03081678c7bbb6/src/objects.cc
[modify] https://crrev.com/3b1b11130c9e9df7f82444b37a03081678c7bbb6/test/mjsunit/wasm/js-api.js

Already merged to M63 at #17.

This bug has been closed for more than 14 weeks. Removing security view restrictions.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot