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

Likely culprit CL: https://chromium-review.googlesource.com/543440 based on files changed.

Looks like a duplicate of  bug 750016  to me.

ClusterFuzz has detected this issue as fixed in range 490847:492300.

Detailed report: https://clusterfuzz.com/testcase?key=5470039187914752

Fuzzer: mbarbella_webcomponents
Job Type: linux_ubsan_vptr_content_shell_drt
Platform Id: linux

Crash Type: Bad-cast
Crash Address: 0x3b07f64580e0
Crash State:
  Bad-cast to blink::LayoutObject from invalid vptr
  blink::LayoutTableSection::RowHasVisibilityCollapse
  blink::LayoutTableCell::ShouldClipOverflow
  
Sanitizer: undefined (UBSAN)

Recommended Security Severity: High

Regressed: https://clusterfuzz.com/revisions?job=linux_ubsan_vptr_content_shell_drt&range=490023:490164
Fixed: https://clusterfuzz.com/revisions?job=linux_ubsan_vptr_content_shell_drt&range=490847:492300

Reproducer Testcase: https://clusterfuzz.com/download?testcase_id=5470039187914752


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.

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