Merge pull request #2951 from autonomys/fix-pot-verification-on-itera…

…tions-change Fix PoT verification when number of iterations change
autonomys · Jul 29, 2024 · 2e4cb25 · 2e4cb25
2 parents 5438c64 + 699bce6
commit 2e4cb25
Show file tree

Hide file tree

Showing 2 changed files with 11 additions and 8 deletions.
diff --git a/crates/pallet-subspace/src/lib.rs b/crates/pallet-subspace/src/lib.rs
@@ -958,6 +958,13 @@ impl<T: Config> Pallet<T> {
         T::EraChangeTrigger::trigger::<T>(block_number);
 
         {
+            let pot_slot_iterations =
+                PotSlotIterations::<T>::get().expect("Always initialized during genesis; qed");
+            // This is what we had after previous block
+            frame_system::Pallet::<T>::deposit_log(DigestItem::pot_slot_iterations(
+                pot_slot_iterations,
+            ));
+
             let mut maybe_pot_slot_iterations_update = PotSlotIterationsUpdate::<T>::get();
             // Check PoT slot iterations update and apply it if it is time to do so, while also
             // removing corresponding storage item
@@ -976,15 +983,11 @@ impl<T: Config> Pallet<T> {
                 PotSlotIterations::<T>::put(update.slot_iterations);
                 update.slot_iterations
             } else {
-                PotSlotIterations::<T>::get().expect("Always initialized during genesis; qed")
+                pot_slot_iterations
             };
             let pot_entropy_injection_interval = T::PotEntropyInjectionInterval::get();
             let pot_entropy_injection_delay = T::PotEntropyInjectionDelay::get();
 
-            frame_system::Pallet::<T>::deposit_log(DigestItem::pot_slot_iterations(
-                pot_slot_iterations,
-            ));
-
             let mut entropy = PotEntropy::<T>::get();
             let lookback_in_blocks = pot_entropy_injection_interval
                 * BlockNumberFor::<T>::from(T::PotEntropyInjectionLookbackDepth::get());

diff --git a/crates/sc-consensus-subspace/src/verifier.rs b/crates/sc-consensus-subspace/src/verifier.rs
@@ -294,7 +294,7 @@ where
             }
 
             let future_slot = slot + self.chain_constants.block_authoring_delay();
-            let slot_to_check = Slot::from(
+            let first_slot_to_check = Slot::from(
                 future_slot
                     .checked_sub(checkpoints.len() as u64 - 1)
                     .ok_or(VerificationError::InvalidProofOfTime)?,
@@ -303,13 +303,13 @@ where
                 .pot_parameters_change
                 .as_ref()
                 .and_then(|parameters_change| {
-                    (parameters_change.slot == slot_to_check)
+                    (parameters_change.slot <= first_slot_to_check)
                         .then_some(parameters_change.slot_iterations)
                 })
                 .unwrap_or(subspace_digest_items.pot_slot_iterations);
 
             let mut pot_input = PotNextSlotInput {
-                slot: slot_to_check,
+                slot: first_slot_to_check,
                 slot_iterations,
                 seed,
             };