From: Alan T. DeKok <aland@freeradius.org>
Date: Mon, 25 Mar 2024 00:56:30 +0000 (-0400)
Subject: try to link test points at compile time
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8702e8c66ccf9b244ef8306de75079ae9dfd1f0f;p=thirdparty%2Ffreeradius-server.git

try to link test points at compile time

instead of using dlsym(), which seems to confuse the fuzzer
coverage tool.

Also create protocol-specific fuzzer_PROTO.c files, to make it
clear that the fuzzers are different.
---

diff --git a/src/bin/all.mk b/src/bin/all.mk
index d056fec7cc8..33227c0d8a7 100644
--- a/src/bin/all.mk
+++ b/src/bin/all.mk
@@ -47,6 +47,10 @@ FUZZER_TIMEOUT   ?= 10
 #  Define a function to do all of the same thing.
 #
 define FUZZ_PROTOCOL
+src/bin/fuzzer_${1}.c: src/bin/fuzzer.c
+	$${Q}sed 's/XX_PROTOCOL_XX/${1}/g' < $$^ > $$@
+
+
 src/bin/fuzzer_${1}.mk: src/bin/fuzzer.mk
 	$${Q}sed 's/$$$$(PROTOCOL)/${1}/g' < $$^ > $$@
 
diff --git a/src/bin/fuzzer.c b/src/bin/fuzzer.c
index 37e6015d736..53468802095 100644
--- a/src/bin/fuzzer.c
+++ b/src/bin/fuzzer.c
@@ -39,13 +39,14 @@ RCSID("$Id$")
  */
 
 static bool			init = false;
-static fr_test_point_proto_decode_t *tp	= NULL;
 static dl_t			*dl = NULL;
 static dl_loader_t		*dl_loader;
 static fr_dict_protocol_t	*dl_proto;
 
 static fr_dict_t		*dict = NULL;
 
+extern fr_test_point_proto_decode_t XX_PROTOCOL_XX_tp_decode_proto;
+
 int LLVMFuzzerInitialize(int *argc, char ***argv);
 int LLVMFuzzerTestOneInput(const uint8_t *buf, size_t len);
 
@@ -85,14 +86,6 @@ fr_dict_protocol_t *fuzzer_dict_init(void *dl_handle, char const *proto)
 	return our_dl_proto;
 }
 
-static inline
-fr_test_point_proto_decode_t *fuzzer_test_point(void *dl_handle, char const *proto)
-{
-	char			buffer[256];
-	snprintf(buffer, sizeof(buffer), "%s_tp_decode_proto", proto);
-	return dlsym(dl_handle, buffer);
-}
-
 int LLVMFuzzerInitialize(int *argc, char ***argv)
 {
 	char const		*lib_dir  	= getenv("FR_LIBRARY_PATH");
@@ -104,7 +97,6 @@ int LLVMFuzzerInitialize(int *argc, char ***argv)
 	char			*dict_dir_to_free = NULL;
 	char			*lib_dir_to_free = NULL;
 #endif
-	char			buffer[1024];
 
 	if (!argc || !argv || !*argv) return -1; /* shut up clang scan */
 
@@ -186,7 +178,7 @@ int LLVMFuzzerInitialize(int *argc, char ***argv)
 		if (!lib_dir) {
 			lib_dir = lib_dir_to_free = talloc_asprintf(NULL, "%.*s/lib", (int) (p - (*argv)[0]), (*argv)[0]);
 			if (!lib_dir_to_free) fr_exit_now(EXIT_FAILURE);
-		}
+<		}
 	}
 #endif
 
@@ -238,32 +230,6 @@ int LLVMFuzzerInitialize(int *argc, char ***argv)
 	 *	or statically linked to the library we're fuzzing...
 	 */
 	dl_proto = fuzzer_dict_init(RTLD_DEFAULT, proto);
-	tp = fuzzer_test_point(RTLD_DEFAULT, proto);
-
-	/*
-	 *	Failed to find the test point, try and load it in
-	 *	dynamically from the protocol library.
-	 */
-	if (!tp) {
-		dl_loader = dl_loader_init(NULL, NULL, 0, false);
-		if (!dl_loader) {
-			fr_perror("fuzzer: Failed initializing library loader");
-			fr_exit_now(EXIT_FAILURE);
-		}
-
-		snprintf(buffer, sizeof(buffer), "libfreeradius-%s", proto);
-		dl = dl_by_name(dl_loader, buffer, NULL, false);
-		if (!dl) {
-			fr_perror("fuzzer: Failed loading library %s", buffer);
-			fr_exit_now(EXIT_FAILURE);
-		}
-
-		if (!dl_proto) dl_proto = fuzzer_dict_init(dl->handle, proto);
-		if (!tp && !(tp = fuzzer_test_point(dl->handle, proto))) {
-			fr_perror("fuzzer: Failed finding test point %s", buffer);
-			fr_exit_now(EXIT_FAILURE);
-		}
-	}
 
 	init = true;
 
@@ -280,6 +246,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *buf, size_t len)
 	TALLOC_CTX *   ctx = talloc_init_const("fuzzer");
 	fr_pair_list_t vps;
 	void *decode_ctx = NULL;
+	fr_test_point_proto_decode_t *tp = &XX_PROTOCOL_XX_tp_decode_proto;
 
 	fr_pair_list_init(&vps);
 	if (!init) LLVMFuzzerInitialize(NULL, NULL);
diff --git a/src/bin/fuzzer.mk b/src/bin/fuzzer.mk
index 7d62890e076..a6fd52891c9 100644
--- a/src/bin/fuzzer.mk
+++ b/src/bin/fuzzer.mk
@@ -18,7 +18,7 @@
 #
 
 TARGET			:= fuzzer_$(PROTOCOL)$(E)
-SOURCES			:= fuzzer.c
+SOURCES			:= fuzzer_$(PROTOCOL).c
 
 TGT_PREREQS		:= libfreeradius-$(PROTOCOL)$(L)