Large Alembic crashes Blender 4.0 #111575

New Issue

Robert Nederhorst · 2023-08-27T02:59:00+02:00

Robert Nederhorst commented

2023-08-27 02:59:00 +02:00

System Information
Operating system: Win11
Graphics card: 4090

Blender Version
Broken: 4.0 Aug 26th build and 3.6 stable build
Worked: n/a

Short description of error

Importing this alembic file causes a segfault:
https://www.dropbox.com/scl/fi/7ty5zf9s8u31swr03m34k/building_06.abc?rlkey=9z8ct3vrt7hhapd6se1gleswg&dl=0

Exact steps for others to reproduce the error
Try to import this file.
This was made with reality capture.

another alembic file from same software does work:
https://www.dropbox.com/scl/fi/7ty5zf9s8u31swr03m34k/building_06.abc?rlkey=9z8ct3vrt7hhapd6se1gleswg&dl=0

Notes:

This is due to overflowing the internal BHead::len field - which is only a signed 32-bit field.

Stack trace:
VCRUNTIME140.dll    :0x00007FFC728B11F0  memcmp
blender.exe         :0x00007FF77712F260  BLO_memfile_chunk_add
blender.exe         :0x00007FF7771210E0  mywrite
blender.exe         :0x00007FF777124430  BLO_write_struct_array_by_name
blender.exe         :0x00007FF776E1B4E0  CustomData_blend_write
blender.exe         :0x00007FF776DAFA70  mesh_blend_write
blender.exe         :0x00007FF777121290  write_file_handle
blender.exe         :0x00007FF777123FC0  BLO_write_file_mem
blender.exe         :0x00007FF77B2FE1D0  BKE_memfile_undo_encode
blender.exe         :0x00007FF777A89D70  memfile_undosys_step_encode
blender.exe         :0x00007FF77B21E0F0  BKE_undosys_step_push_with_type
blender.exe         :0x00007FF77B21DF30  BKE_undosys_step_push
blender.exe         :0x00007FF777A8ACF0  ED_undo_push

**System Information** Operating system: Win11 Graphics card: 4090 **Blender Version** Broken: 4.0 Aug 26th build and 3.6 stable build Worked: n/a **Short description of error** Importing this alembic file causes a segfault: https://www.dropbox.com/scl/fi/7ty5zf9s8u31swr03m34k/building_06.abc?rlkey=9z8ct3vrt7hhapd6se1gleswg&dl=0 **Exact steps for others to reproduce the error** Try to import this file. This was made with reality capture. another alembic file from same software does work: https://www.dropbox.com/scl/fi/7ty5zf9s8u31swr03m34k/building_06.abc?rlkey=9z8ct3vrt7hhapd6se1gleswg&dl=0 Notes: This is due to overflowing the internal `BHead::len` field - which is only a signed 32-bit field. ``` Stack trace: VCRUNTIME140.dll :0x00007FFC728B11F0 memcmp blender.exe :0x00007FF77712F260 BLO_memfile_chunk_add blender.exe :0x00007FF7771210E0 mywrite blender.exe :0x00007FF777124430 BLO_write_struct_array_by_name blender.exe :0x00007FF776E1B4E0 CustomData_blend_write blender.exe :0x00007FF776DAFA70 mesh_blend_write blender.exe :0x00007FF777121290 write_file_handle blender.exe :0x00007FF777123FC0 BLO_write_file_mem blender.exe :0x00007FF77B2FE1D0 BKE_memfile_undo_encode blender.exe :0x00007FF777A89D70 memfile_undosys_step_encode blender.exe :0x00007FF77B21E0F0 BKE_undosys_step_push_with_type blender.exe :0x00007FF77B21DF30 BKE_undosys_step_push blender.exe :0x00007FF777A8ACF0 ED_undo_push ```

Robert Nederhorst added the

labels 2023-08-27 02:59:00 +02:00

Iliya Katushenock added the