2.30b

afl-fuzz.c

@@ -116,7 +116,8 @@ EXP_ST u8  skip_deterministic,        /* Skip deterministic stages?       */
            bitmap_changed = 1,        /* Time to update bitmap?           */
            qemu_mode,                 /* Running in QEMU mode?            */
            skip_requested,            /* Skip request, via SIGUSR1        */
-           run_over10m;               /* Run time over 10 minutes?        */
+           run_over10m,               /* Run time over 10 minutes?        */
+           persistent_mode;           /* Running in persistent mode?      */
 
 static s32 out_fd,                    /* Persistent fd for out_file       */
            dev_urandom_fd = -1,       /* Persistent fd for /dev/urandom   */
@@ -396,7 +397,7 @@ static void bind_to_free_cpu(void) {
   u8 cpu_used[4096] = { 0 };
   u32 i;
 
-  if (!cpu_core_count) return;
+  if (cpu_core_count < 2) return;
 
   if (getenv("AFL_NO_AFFINITY")) {
 
@@ -2401,7 +2402,8 @@ static u8 run_target(char** argv) {
 
   }
 
-  child_pid = 0;
+  if (!WIFSTOPPED(status)) child_pid = 0;
+
   it.it_value.tv_sec = 0;
   it.it_value.tv_usec = 0;
 
@@ -4199,8 +4201,9 @@ static void show_stats(void) {
   if (t_bytes) sprintf(tmp, "%0.02f%%", stab_ratio);
     else strcpy(tmp, "n/a");
 
-  SAYF(" stability : %s%-10s " bSTG bV "\n", stab_ratio < 90 ? cLRD :
-          (queued_variable ? cMGN : cRST), tmp);
+  SAYF(" stability : %s%-10s " bSTG bV "\n", (stab_ratio < 85 && var_byte_count > 40) 
+       ? cLRD : ((queued_variable && (!persistent_mode || var_byte_count > 20))
+       ? cMGN : cRST), tmp);
 
   if (!bytes_trim_out) {
 
@@ -6858,6 +6861,7 @@ EXP_ST void check_binary(u8* fname) {
 
     OKF(cPIN "Persistent mode binary detected.");
     setenv(PERSIST_ENV_VAR, "1", 1);
+    persistent_mode = 1;
 
   } else if (getenv("AFL_PERSISTENT")) {
 

config.h

@@ -21,7 +21,7 @@
 
 /* Version string: */
 
-#define VERSION             "2.29b"
+#define VERSION             "2.30b"
 
 /******************************************************
  *                                                    *

docs/ChangeLog

@@ -16,6 +16,20 @@ Not sure if you should upgrade? The lowest currently recommended version
 is 2.23b. If you're stuck on an earlier release, it's strongly advisable
 to get on with the times.
 
+--------------
+Version 2.30b:
+--------------
+
+  - Made minor improvements to persistent mode to avoid the remote
+    possibility of "no instrumentation detected" issues with very low
+    instrumentation densities.
+
+  - Fixed a minor glitch with a leftover process in persistent mode.
+    Reported by Jakub Wilk and Daniel Stender.
+
+  - Made persistent mode bitmaps a bit more consistent and adjusted the way
+    this is shown in the UI, especially in persistent mode.
+
 --------------
 Version 2.29b:
 --------------

docs/status_screen.txt

@@ -297,10 +297,10 @@ number of inputs that produce seemingly variable behavior in the tested binary.
 
 That last bit is actually fairly interesting: it measures the consistency of
 observed traces. If a program always behaves the same for the same input data,
-it will earn a score of 100%. When the value is over 90%, the fuzzing process
-is still unlikely to be negatively affected. If it gets much lower, you may
-be in trouble, since AFL will have difficulty discerning between meaningful
-and "phantom" effects of tweaking the input file.
+it will earn a score of 100%. When the value is lower but still shown in purple,
+the fuzzing process is unlikely to be negatively affected. If it goes into red,
+you may be in trouble, since AFL will have difficulty discerning between
+meaningful and "phantom" effects of tweaking the input file.
 
 Now, most targets will just get a 100% score, but when you see lower figures,
 there are several things to look at:

llvm_mode/afl-llvm-rt.o.c

@@ -176,8 +176,10 @@ int __afl_persistent_loop(unsigned int max_cnt) {
        before the loop. */
 
     if (is_persistent) {
+
       memset(__afl_area_ptr, 0, MAP_SIZE);
       __afl_area_ptr[0] = 1;
+      __afl_prev_loc = 0;
     }
 
     cycle_cnt  = max_cnt;
@@ -191,6 +193,10 @@ int __afl_persistent_loop(unsigned int max_cnt) {
     if (--cycle_cnt) {
 
       raise(SIGSTOP);
+
+      __afl_area_ptr[0] = 1;
+      __afl_prev_loc = 0;
+
       return 1;
 
     } else {