perf(internal/blocksync): avoid double-calling types.BlockFromProto…

… (backport cometbft#2016) (cometbft#2145)

This is an automatic backport of pull request cometbft#2016 done by
[Mergify](https://mergify.com).
Cherry-pick of f4d73cd has failed:
```
On branch mergify/bp/v0.38.x/pr-2016
Your branch is up to date with 'origin/v0.38.x'.

You are currently cherry-picking commit f4d73cd.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Changes to be committed:
	modified:   blocksync/msgs.go
	modified:   blocksync/reactor.go

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	added by them:   .changelog/v0.38.3/improvements/2016-blocksync-avoid-double-calling-block-from-proto.md

```


To fix up this pull request, you can check it out locally. See
documentation:
https://docs.github.com/en/github/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally

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</details>

---------

Co-authored-by: Anton Kaliaev <[email protected]>

.changelog/unreleased/improvements/2016-blocksync-avoid-double-calling-block-from-proto.md

@@ -0,0 +1,2 @@
+- `[blocksync]` Avoid double-calling `types.BlockFromProto` for performance
+  reasons ([\#2016](https://github.com/cometbft/cometbft/pull/2016))

.gitignore

@@ -57,3 +57,4 @@ proto/spec/**/*.pb.go
 *.dvi
 # Python virtual environments
 .venv
+go.work.sum

blocksync/msgs.go

@@ -30,10 +30,9 @@ func ValidateMsg(pb proto.Message) error {
 			return ErrInvalidHeight{Height: msg.Height, Reason: "negative height"}
 		}
 	case *bcproto.BlockResponse:
-		_, err := types.BlockFromProto(msg.Block)
-		if err != nil {
-			return err
-		}
+		// Avoid double-calling `types.BlockFromProto` for performance reasons.
+		// See https://github.com/cometbft/cometbft/issues/1964
+		return nil
 	case *bcproto.NoBlockResponse:
 		if msg.Height < 0 {
 			return ErrInvalidHeight{Height: msg.Height, Reason: "negative height"}

blocksync/reactor.go

@@ -251,7 +251,8 @@ func (bcR *Reactor) Receive(e p2p.Envelope) {
 	case *bcproto.BlockResponse:
 		bi, err := types.BlockFromProto(msg.Block)
 		if err != nil {
-			bcR.Logger.Error("Block content is invalid", "err", err)
+			bcR.Logger.Error("Peer sent us invalid block", "peer", e.Src, "msg", e.Message, "err", err)
+			bcR.Switch.StopPeerForError(e.Src, err)
 			return
 		}
 		var extCommit *types.ExtendedCommit
@@ -262,6 +263,7 @@ func (bcR *Reactor) Receive(e p2p.Envelope) {
 				bcR.Logger.Error("failed to convert extended commit from proto",
 					"peer", e.Src,
 					"err", err)
+				bcR.Switch.StopPeerForError(e.Src, err)
 				return
 			}
 		}