Rx Buffer overflow in MCP2515 CAN controller
I was facing the Rx buffer overflow issue when interfacing with mcp25625. This was caused due the CS pin being held low for a longer duration than it takes for CAN message to be transmitted.The MCP2515 Silicon Errata mentions this scenario and a workaround for it.
Use the SPI RTS command to trigger the transmission instead of using the transmission request bit TXREQ in register. This solved it for me.