[Minor] Do not read out of the bounds

diff --git a/src/libutil/str_util.c b/src/libutil/str_util.c
index 7c2a545c07bbcc3cd1ff9bb432eaae83ca6958f2..026e331feae5b15fbc0f1a8f29b60576031f8d2a 100644 (file)
--- a/src/libutil/str_util.c
+++ b/src/libutil/str_util.c
@@ -1261,7 +1261,7 @@ rspamd_substring_preprocess_kmp (const gchar *pat, gsize len, goffset *fsm,
                i++;
                j++;
 
-               if (f(pat[i], pat[j])) {
+               if (i < len && j < len && f(pat[i], pat[j])) {
                        fsm[i] = fsm[j];
                }
                else {