Merge branch 'dl/remote-curl-deadlock-fix'

On-the-wire protocol v2 easily falls into a deadlock between the
remote-curl helper and the fetch-pack process when the server side
prematurely throws an error and disconnects.  The communication has
been updated to make it more robust.

* dl/remote-curl-deadlock-fix:
  stateless-connect: send response end packet
  pkt-line: define PACKET_READ_RESPONSE_END
  remote-curl: error on incomplete packet
  pkt-line: extern packet_length()
  transport: extract common fetch_pack() call
  remote-curl: remove label indentation
  remote-curl: fix typo

1 files changed, 17 insertions, 1 deletions

diff --git a/connect.c b/connect.c
index 23013c6344..0df45a1108 100644
--- a/connect.c
+++ b/connect.c
@@ -127,6 +127,7 @@ enum protocol_version discover_version(struct packet_reader *reader)
 		die_initial_contact(0);
 	case PACKET_READ_FLUSH:
 	case PACKET_READ_DELIM:
+	case PACKET_READ_RESPONSE_END:
 		version = protocol_v0;
 		break;
 	case PACKET_READ_NORMAL:
@@ -310,6 +311,7 @@ struct ref **get_remote_heads(struct packet_reader *reader,
 			state = EXPECTING_DONE;
 			break;
 		case PACKET_READ_DELIM:
+		case PACKET_READ_RESPONSE_END:
 			die(_("invalid packet"));
 		}
 
@@ -404,10 +406,21 @@ out:
 	return ret;
 }
 
+void check_stateless_delimiter(int stateless_rpc,
+			      struct packet_reader *reader,
+			      const char *error)
+{
+	if (!stateless_rpc)
+		return; /* not in stateless mode, no delimiter expected */
+	if (packet_reader_read(reader) != PACKET_READ_RESPONSE_END)
+		die("%s", error);
+}
+
 struct ref **get_remote_refs(int fd_out, struct packet_reader *reader,
 			     struct ref **list, int for_push,
 			     const struct argv_array *ref_prefixes,
-			     const struct string_list *server_options)
+			     const struct string_list *server_options,
+			     int stateless_rpc)
 {
 	int i;
 	*list = NULL;
@@ -444,6 +457,9 @@ struct ref **get_remote_refs(int fd_out, struct packet_reader *reader,
 	if (reader->status != PACKET_READ_FLUSH)
 		die(_("expected flush after ref listing"));
 
+	check_stateless_delimiter(stateless_rpc, reader,
+				  _("expected response end packet after ref listing"));
+
 	return list;
 }