Disallow reentrancy

Signed-off-by: Oliver Tale-Yazdi <[email protected]>

substrate/frame/message-queue/src/lib.rs

@@ -555,6 +555,8 @@ pub mod pallet {
 		///
 		/// This can change at any time and may resolve in the future by re-trying.
 		QueuePaused,
+		/// Another call is in progress and needs to finish before this call can happen.
+		RecursiveDisallowed,
 	}
 
 	/// The index of the first and last (non-empty) pages.
@@ -869,6 +871,21 @@ impl<T: Config> Pallet<T> {
 		page_index: PageIndex,
 		index: T::Size,
 		weight_limit: Weight,
+	) -> Result<Weight, Error<T>> {
+		match with_service_mutex(|| {
+			Self::do_execute_overweight_inner(origin, page_index, index, weight_limit)
+		}) {
+			Err(()) => Err(Error::<T>::RecursiveDisallowed),
+			Ok(x) => x,
+		}
+	}
+
+	/// Same as `do_execute_overweight` but must be called while holding the `service_mutex`.
+	fn do_execute_overweight_inner(
+		origin: MessageOriginOf<T>,
+		page_index: PageIndex,
+		index: T::Size,
+		weight_limit: Weight,
 	) -> Result<Weight, Error<T>> {
 		let mut book_state = BookStateFor::<T>::get(&origin);
 		ensure!(!T::QueuePausedQuery::is_paused(&origin), Error::<T>::QueuePaused);
@@ -925,6 +942,14 @@ impl<T: Config> Pallet<T> {
 
 	/// Remove a stale page or one which has no more messages remaining to be processed.
 	fn do_reap_page(origin: &MessageOriginOf<T>, page_index: PageIndex) -> DispatchResult {
+		match with_service_mutex(|| Self::do_reap_page_inner(origin, page_index)) {
+			Err(()) => Err(Error::<T>::RecursiveDisallowed.into()),
+			Ok(x) => x,
+		}
+	}
+
+	/// Same as `do_reap_page` but must be called while holding the `service_mutex`.
+	fn do_reap_page_inner(origin: &MessageOriginOf<T>, page_index: PageIndex) -> DispatchResult {
 		let mut book_state = BookStateFor::<T>::get(origin);
 		// definitely not reapable if the page's index is no less than the `begin`ning of ready
 		// pages.
@@ -1428,35 +1453,40 @@ impl<T: Config> ServiceQueues for Pallet<T> {
 			Weight::zero()
 		});
 
-		let mut next = match Self::bump_service_head(&mut weight) {
-			Some(h) => h,
-			None => return weight.consumed(),
-		};
-		// The last queue that did not make any progress.
-		// The loop aborts as soon as it arrives at this queue again without making any progress
-		// on other queues in between.
-		let mut last_no_progress = None;
-
-		loop {
-			let (progressed, n) = Self::service_queue(next.clone(), &mut weight, max_weight);
-			next = match n {
-				Some(n) =>
-					if !progressed {
-						if last_no_progress == Some(n.clone()) {
-							break
-						}
-						if last_no_progress.is_none() {
-							last_no_progress = Some(next.clone())
-						}
-						n
-					} else {
-						last_no_progress = None;
-						n
-					},
-				None => break,
+		match with_service_mutex(|| {
+			let mut next = match Self::bump_service_head(&mut weight) {
+				Some(h) => h,
+				None => return weight.consumed(),
+			};
+			// The last queue that did not make any progress.
+			// The loop aborts as soon as it arrives at this queue again without making any progress
+			// on other queues in between.
+			let mut last_no_progress = None;
+
+			loop {
+				let (progressed, n) = Self::service_queue(next.clone(), &mut weight, max_weight);
+				next = match n {
+					Some(n) =>
+						if !progressed {
+							if last_no_progress == Some(n.clone()) {
+								break
+							}
+							if last_no_progress.is_none() {
+								last_no_progress = Some(next.clone())
+							}
+							n
+						} else {
+							last_no_progress = None;
+							n
+						},
+					None => break,
+				}
 			}
+			weight.consumed()
+		}) {
+			Err(()) => weight.consumed(),
+			Ok(w) => w,
 		}
-		weight.consumed()
 	}
 
 	/// Execute a single overweight message.
@@ -1484,6 +1514,7 @@ impl<T: Config> ServiceQueues for Pallet<T> {
 				Error::<T>::QueuePaused => ExecuteOverweightError::QueuePaused,
 				Error::<T>::NoPage | Error::<T>::NoMessage | Error::<T>::Queued =>
 					ExecuteOverweightError::NotFound,
+				Error::<T>::RecursiveDisallowed => ExecuteOverweightError::RecursiveDisallowed,
 				_ => ExecuteOverweightError::Other,
 			},
 		)