1 files changed, 4 insertions, 1 deletions
diff --git a/re.c b/re.c
index 99759c93d9..67ee4dfc1b 100644
--- a/re.c
+++ b/re.c
@@ -613,7 +613,10 @@ rb_reg_search(re, str, pos, reverse)
     static struct re_registers regs;
     int range;
 
-    if (pos > RSTRING(str)->len) return -1;
+    if (pos > RSTRING(str)->len || pos < 0) {
+	rb_backref_set(Qnil);
+	return -1;
+    }
 
     rb_reg_check(re);
     if (may_need_recompile) rb_reg_prepare_re(re);