Make sure we don't use cheat codes to form fuzzing call sequences (#993)

crytic · Mar 22, 2023 · a2d5b14 · a2d5b14
1 parent eea4296
commit a2d5b14
Showing 2 changed files with 6 additions and 3 deletions.
diff --git a/lib/Echidna.hs b/lib/Echidna.hs
@@ -70,7 +70,8 @@ prepareContract env contracts solFiles specifiedContract seed = do
                   <> deployedAddresses
 
   let dict = mkGenDict env.cfg.campaignConf.dictFreq
-                       constants
+                       -- make sure we don't use cheat codes to form fuzzing call sequences
+                       (Set.delete (AbiAddress cheatCode) constants)
                        Set.empty
                        seed
                        (returnTypes contracts)

diff --git a/lib/Echidna/Campaign.hs b/lib/Echidna/Campaign.hs
@@ -24,7 +24,7 @@ import Data.Set qualified as Set
 import Data.Text (Text)
 import System.Random (mkStdGen)
 
-import EVM (Contract, VM(..), VMResult(..), bytecode)
+import EVM (Contract, VM(..), VMResult(..), bytecode, cheatCode)
 import EVM qualified (Env(..))
 import EVM.ABI (getAbi, AbiType(AbiAddressType), AbiValue(AbiAddress))
 import EVM.Types (Addr, Expr(ConcreteBuf))
@@ -246,7 +246,9 @@ callseq initialCorpus vm world seqLen = do
       case result of
         VMSuccess (ConcreteBuf buf) ->
           case runGetOrFail (getAbi type') (LBS.fromStrict buf) of
-            Right (_, _, abiValue) -> Just (type', Set.singleton abiValue)
+            -- make sure we don't use cheat codes to form fuzzing call sequences
+            Right (_, _, abiValue) | abiValue /= AbiAddress cheatCode ->
+              Just (type', Set.singleton abiValue)
             _ -> Nothing
         _ -> Nothing