update Nyx custom harness:
use a coverage bitmap that is smaller than 64k
#include <inttypes.h>
#include "nyx.h"
-#define TRACE_BUFFER_SIZE (1024 * 64)
+#define TRACE_BUFFER_SIZE (64)
+
+#define PAGE_SIZE 0x1000
+#define MMAP_SIZE(x) ((x & ~(PAGE_SIZE-1)) + PAGE_SIZE)
int main(int argc, char **argv) {
@@ -27,8 +30,8 @@ int main(int argc, char **argv) {
/* this is our "bitmap" that is later shared with the fuzzer (you can also
* pass the pointer of the bitmap used by compile-time instrumentations in
* your target) */
- uint8_t *trace_buffer = mmap(NULL, TRACE_BUFFER_SIZE, PROT_READ | PROT_WRITE,
- MAP_SHARED | MAP_ANONYMOUS, -1, 0);
+ uint8_t *trace_buffer = mmap(NULL, MMAP_SIZE(TRACE_BUFFER_SIZE), PROT_READ |
+ PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, -1, 0);
memset(trace_buffer, 0,
TRACE_BUFFER_SIZE); // makes sure that the bitmap buffer is already
// mapped into the guest's memory (alternatively
