AFL_IGNORE_PROBLEMS + library checks and documentation

3 files changed, 22 insertions, 0 deletions

diff --git a/src/afl-fuzz-state.c b/src/afl-fuzz-state.c
index b832c11e..24ccc108 100644
--- a/src/afl-fuzz-state.c
+++ b/src/afl-fuzz-state.c
@@ -267,6 +267,13 @@ void read_afl_environment(afl_state_t *afl, char **envp) {
             afl->afl_env.afl_force_ui =
                 get_afl_env(afl_environment_variables[i]) ? 1 : 0;
 
+          } else if (!strncmp(env, "AFL_IGNORE_PROBLEMS",
+
+                              afl_environment_variable_len)) {
+
+            afl->afl_env.afl_ignore_problems =
+                get_afl_env(afl_environment_variables[i]) ? 1 : 0;
+
           } else if (!strncmp(env, "AFL_I_DONT_CARE_ABOUT_MISSING_CRASHES",
 
                               afl_environment_variable_len)) {
diff --git a/src/afl-fuzz-stats.c b/src/afl-fuzz-stats.c
index ead65b1d..a9deb22d 100644
--- a/src/afl-fuzz-stats.c
+++ b/src/afl-fuzz-stats.c
@@ -534,6 +534,20 @@ void show_stats(afl_state_t *afl) {
   t_bytes = count_non_255_bytes(afl, afl->virgin_bits);
   t_byte_ratio = ((double)t_bytes * 100) / afl->fsrv.real_map_size;
 
+  if (unlikely(t_bytes > afl->fsrv.real_map_size)) {
+
+    if (unlikely(!afl->afl_env.afl_ignore_problems)) {
+
+      FATAL(
+          "Incorrect fuzzing setup detected. Your target seems to have loaded "
+          "incorrectly instrumented shared libraries. If you use LTO mode "
+          "please see instrumentation/README.lto.md. To ignore this problem "
+          "and continue fuzzing just set 'AFL_IGNORE_PROBLEMS=1'.\n");
+
+    }
+
+  }
+
   if (likely(t_bytes) && unlikely(afl->var_byte_count)) {
 
     stab_ratio = 100 - (((double)afl->var_byte_count * 100) / t_bytes);
diff --git a/src/afl-fuzz.c b/src/afl-fuzz.c
index 9b9e01a4..8ffc0e77 100644
--- a/src/afl-fuzz.c
+++ b/src/afl-fuzz.c
@@ -216,6 +216,7 @@ static void usage(u8 *argv0, int more_help) {
       "AFL_HANG_TMOUT: override timeout value (in milliseconds)\n"
       "AFL_I_DONT_CARE_ABOUT_MISSING_CRASHES: don't warn about core dump handlers\n"
       "AFL_IGNORE_UNKNOWN_ENVS: don't warn on unknown env vars\n"
+      "AFL_IGNORE_PROBLEMS: do not abort fuzzing if an incorrect setup is detected during a run\n"
       "AFL_IMPORT_FIRST: sync and import test cases from other fuzzer instances first\n"
       "AFL_KILL_SIGNAL: Signal ID delivered to child processes on timeout, etc. (default: SIGKILL)\n"
       "AFL_MAP_SIZE: the shared memory size for that target. must be >= the size\n"