fuzz-tests: add a test for handle_peer_error_or_warning()

handle_peer_error_or_warning() in common/read_peer_message is
responsible for parsing any incoming `error` or `warning`
messages as defined in BOLT #1. Add a test for it.

Author: Chandra Pratap

tests/fuzz/Makefile

@@ -48,8 +48,13 @@ FUZZ_COMMON_OBJS := \
 	common/memleak.o				\
 	common/msg_queue.o				\
 	common/node_id.o				\
+	common/peer_billboard.o				\
+	common/peer_failed.o				\
+	common/peer_io.o				\
+	common/peer_status_wiregen.o			\
 	common/permute_tx.o				\
 	common/psbt_keypath.o				\
+	common/read_peer_msg.o				\
 	common/sciddir_or_pubkey.o			\
 	common/setup.o					\
 	common/status.o					\
@@ -58,6 +63,7 @@ FUZZ_COMMON_OBJS := \
 	common/utils.o					\
 	common/version.o				\
 	common/wireaddr.o				\
+	common/wire_error.o				\
 	wire/bolt12_wiregen.o				\
 	wire/channel_type_wiregen.o			\
 	wire/fromwire.o					\

tests/fuzz/fuzz-error-warning.c

@@ -0,0 +1,17 @@
+#include "config.h"
+#include <common/per_peer_state.h>
+#include <common/read_peer_msg.h>
+#include <tests/fuzz/libfuzz.h>
+
+void init(int *argc, char ***argv)
+{
+}
+
+void run(const u8 *data, size_t size)
+{
+    struct per_peer_state pps = { .peer_fd = -1 };
+    u8 *buf = tal_dup_arr(NULL, u8, data, size, 0);
+    handle_peer_error_or_warning(&pps, buf);
+
+    tal_free(buf);
+}