commit-graph, fuzz: add fuzzer for commit-graph

diff --git a/fetch-pack.c b/fetch-pack.c
index 25a88f4eb27f730f4d3a702251ace3a03748cf1e..dd6700bda9240f2278e663f9147df1c0808d2efc 100644 (file)
--- a/fetch-pack.c
+++ b/fetch-pack.c
@@ -1213,6 +1213,18 @@ static int process_acks(struct fetch_negotiator *negotiator,
            reader->status != PACKET_READ_DELIM)
                die(_("error processing acks: %d"), reader->status);
 
+       /*
+        * If an "acknowledgments" section is sent, a packfile is sent if and
+        * only if "ready" was sent in this section. The other sections
+        * ("shallow-info" and "wanted-refs") are sent only if a packfile is
+        * sent. Therefore, a DELIM is expected if "ready" is sent, and a FLUSH
+        * otherwise.
+        */
+       if (received_ready && reader->status != PACKET_READ_DELIM)
+               die(_("expected packfile to be sent after 'ready'"));
+       if (!received_ready && reader->status != PACKET_READ_FLUSH)
+               die(_("expected no other sections to be sent after no 'ready'"));
+
        /* return 0 if no common, 1 if there are common, or 2 if ready */
        return received_ready ? 2 : (received_ack ? 1 : 0);
 }