diff --git a/src/lib/third_party/src/ahocorasick.c b/src/lib/third_party/src/ahocorasick.c
index c309c043e91..fb56ace730e 100644
--- a/src/lib/third_party/src/ahocorasick.c
+++ b/src/lib/third_party/src/ahocorasick.c
@@ -335,7 +335,7 @@ AC_ERROR_t ac_automata_walk(AC_AUTOMATA_t * thiz,
     }
 
     path[ip].idx = i+1;
-    if(ip >= AC_PATTRN_MAX_LENGTH)
+    if(ip > AC_PATTRN_MAX_LENGTH)
         continue;
 
     ip++;