Fix cmin (#2420)

* fix minimizer

* clp

libafl/src/corpus/minimizer.rs

@@ -99,6 +99,9 @@ where
         EM: EventFirer<State = E::State>,
         Z: HasScheduler<Scheduler = CS, State = E::State>,
     {
+        // don't delete this else it won't work after restart
+        let current = *state.corpus().current();
+
         let cfg = Config::default();
         let ctx = Context::new(&cfg);
         let opt = Optimize::new(&ctx);
@@ -224,6 +227,10 @@ where
             // reverse order; if indexes are stored in a vec, we need to remove from back to front
             removed.sort_unstable_by(|id1, id2| id2.cmp(id1));
             for id in removed {
+                if let Some(_cur) = current {
+                    continue;
+                }
+
                 let removed = state.corpus_mut().remove(id)?;
                 // scheduler needs to know we've removed the input, or it will continue to try
                 // to use now-missing inputs

libafl/src/schedulers/mod.rs

@@ -48,6 +48,7 @@ where
     Self::State: HasCorpus,
 {
     /// Removed the given entry from the corpus at the given index
+    /// When you remove testcases, make sure that that testcase is not currently fuzzed one!
     fn on_remove(
         &mut self,
         _state: &mut Self::State,