[libFuzzer] Don't count leak-verification re-executions towards `-runs` (#221036)

Fixes #66331. Stop countring the verification run in
TryDetectingAMemoryLeak() as part of TotalNumberOfRuns, as the number of
executed units could exceed -runs=N.

GitOrigin-RevId: 3ff11b27bbd8eca219dab55e9589fcf6a76a79cb

FuzzerLoop.cpp

diff --git a/FuzzerLoop.cpp b/FuzzerLoop.cpp
index d8e6379..084f91d 100644
--- a/FuzzerLoop.cpp
+++ b/FuzzerLoop.cpp
@@ -683,9 +683,6 @@
     return; // mallocs==frees, a leak is unlikely.
   if (!Options.DetectLeaks)
     return;
-  if (!DuringInitialCorpusExecution &&
-      TotalNumberOfRuns >= Options.MaxNumberOfRuns)
-    return;
   if (!&(EF->__lsan_enable) || !&(EF->__lsan_disable) ||
       !(EF->__lsan_do_recoverable_leak_check))
     return; // No lsan.
@@ -694,6 +691,10 @@
   EF->__lsan_disable();
   ExecuteCallback(Data, Size);
   EF->__lsan_enable();
+  // The above is a verification run, and not a fuzzing run, without the
+  // correction the number of runs would exceed -runs.
+  // See https://github.com/llvm/llvm-project/issues/66331
+  TotalNumberOfRuns--;
   if (!HasMoreMallocsThanFrees)
     return; // a leak is unlikely.
   if (NumberOfLeakDetectionAttempts++ > 1000) {