Tech Note: Crash in Control Rig VM due to memory stomping

Dec 8, 2021.Knowledge

Summary: A Control Rig VM crash has been found in non-editor builds due to a memory stomping issue. The issue reproduces as a fatal log in FMallocBinned2::GetAllocationSizeExternal(): “FMallocBinned2 Attempt to GetAllocationSizeExternal an unrecognized block”.

Potential Impact: Moderate: Certain configurations of Control Rig graphs using the Full Body IK solver node will crash in non-editor builds.

Solution: The issue has been fixed in CL 16020071. These changes can be integrated locally. They will also be included with the 4.27 release.