Base rollup validates public reads at start state and not current state

[rahul-kothari]

Imagine you have a transaction that does some public writes and reads the same data later. Then for the base rollup to validate, it must validate that kernel tx not with the start state, but with the current state (after the writes).

Yet here we validate with the start state.

aztec-packages/circuits/cpp/src/aztec3/circuits/rollup/base/native_base_rollup_circuit.cpp

Line 423 in 89d700d

baseRollupInputs.start_public_data_tree_root,

As a result any tx that does both reads and writes to the same data would fail at the base rollup with Membership check failed: base_rollup_circuit: validate_public_data_reads index i

This blocks #2167

[LHerskind]

Spoke with @dbanks12, and the full solution need to handle ordering of public state changes. Until we have that, we can however do a workaround where we are simply skipping the check in the kernel for now.

Why can we do this? While it would be insecure to do, we can do it for the sandbox since the simulator is trusted to follow the rules and enforce the correct ordering.

[rahul-kothari]

In #2559, Commenting out the corresponding check in base rollup until this is fixed.