Memory allocation problems while exploiting stack buffer overflow.

I’m doing 0xdiablos

i found offset, when trying to overwrite EIP it always equals to 0x0

Whenever i use offset - 1 i successfully overwrite every but last byte of EIP, when I use full offset and ideally it should overwrite EIP it’s just 0x0.

“0x00000000 Returned by keyword “new” if memory allocation failed”

ASLR turned off, any ideas about where to look? Happens no matter which function address I try to put in EIP.