Use DecodeWithMemLimit for Block

Author: serban300

substrate/primitives/runtime/src/generic/block.rs

@@ -32,8 +32,12 @@ use crate::{
 	Justifications,
 };
 use alloc::vec::Vec;
+use codec::{DecodeWithMemLimit, Error, Input};
 use sp_core::RuntimeDebug;
 
+/// Maximum heap size for a block (in bytes).
+const MAX_BLOCK_HEAP_SIZE: usize = 50 * 1024 * 1024; // 50 MiB
+
 /// Something to identify a block.
 #[derive(PartialEq, Eq, Clone, Encode, Decode, RuntimeDebug)]
 pub enum BlockId<Block: BlockT> {
@@ -79,18 +83,34 @@ impl<Block: BlockT> fmt::Display for BlockId<Block> {
 
 /// Abstraction over a substrate block.
 #[derive(
-	PartialEq, Eq, Clone, Encode, Decode, DecodeWithMemTracking, RuntimeDebug, scale_info::TypeInfo,
+	PartialEq, Eq, Clone, Encode, DecodeWithMemTracking, RuntimeDebug, scale_info::TypeInfo,
 )]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
 #[cfg_attr(feature = "serde", serde(rename_all = "camelCase"))]
 #[cfg_attr(feature = "serde", serde(deny_unknown_fields))]
+#[codec(decode_with_mem_tracking_bound(
+	Header: DecodeWithMemTracking,
+	Extrinsic: DecodeWithMemTracking)
+)]
 pub struct Block<Header, Extrinsic> {
 	/// The block header.
 	pub header: Header,
 	/// The accompanying extrinsics.
 	pub extrinsics: Vec<Extrinsic>,
 }
 
+impl<Header, Extrinsic> Decode for Block<Header, Extrinsic>
+where
+	Header: DecodeWithMemTracking,
+	Extrinsic: DecodeWithMemTracking,
+{
+	fn decode<I: Input>(input: &mut I) -> Result<Self, Error> {
+		let (header, extrinsics) =
+			DecodeWithMemLimit::decode_with_mem_limit(input, MAX_BLOCK_HEAP_SIZE)?;
+		Ok(Self { header, extrinsics })
+	}
+}
+
 impl<Header, Extrinsic> traits::HeaderProvider for Block<Header, Extrinsic>
 where
 	Header: HeaderT,