From acef0fb4c61d2e8f7830c985ae64fe02248b2382 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tim=20R=C3=BChsen?= <tim.ruehsen@gmx.de>
Date: Sun, 3 Mar 2019 17:05:44 +0100
Subject: [PATCH] * fuzz/wget_ftpls_fuzzer.c: Fix fuzzer

---
 fuzz/wget_ftpls_fuzzer.c | 34 ++++++++++++++++++++++++++++++----
 1 file changed, 30 insertions(+), 4 deletions(-)

diff --git a/fuzz/wget_ftpls_fuzzer.c b/fuzz/wget_ftpls_fuzzer.c
index 857b6a32..2b674859 100644
--- a/fuzz/wget_ftpls_fuzzer.c
+++ b/fuzz/wget_ftpls_fuzzer.c
@@ -59,25 +59,48 @@ FILE *fopen_wgetrc(const char *pathname, const char *mode)
 	return NULL;
 }
 
+static int do_jump;
+static jmp_buf jmpbuf;
 #ifdef FUZZING
 void exit_wget(int status)
 {
+	longjmp(jmpbuf, 1);
+}
+#elif defined HAVE_DLFCN_H
+#include <dlfcn.h> // dlsym
+#ifndef RTLD_NEXT
+#define RTLD_NEXT RTLD_GLOBAL
+#endif
+void exit(int status)
+{
+	if (do_jump) {
+		longjmp(jmpbuf, 1);
+	} else {
+		void (*libc_exit)(int) = (void(*)(int)) dlsym (RTLD_NEXT, "exit");
+		libc_exit(status);
+	}
 }
 #endif
 
 int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
 {
+#ifdef HAVE_FMEMOPEN
 	FILE *fp;
 	struct fileinfo *fi;
 
 	if (size > 4096) // same as max_len = ... in .options file
 		return 0;
 
-	CLOSE_STDERR
-
 	fp = fmemopen((void *) data, size, "r");
 	if (!fp) return 0;
 
+	CLOSE_STDERR
+
+	do_jump = 1;
+
+	if (setjmp(jmpbuf))
+		goto done;
+
 	fi = ftp_parse_ls_fp(fp, ST_UNIX);
 	freefileinfo(fi);
 	rewind(fp);
@@ -91,11 +114,14 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
 	rewind(fp);
 
 	fi = ftp_parse_ls_fp(fp, ST_MACOS);
-	freefileinfo(fi);
 
+done:
+	freefileinfo(fi);
 	fclose(fp);
 
-	RESTORE_STDERR
+	do_jump = 0;
 
+	RESTORE_STDERR
+#endif
 	return 0;
 }