fix #59 : access to invalid address by reg->dmax value

diff --git a/src/regexec.c b/src/regexec.c
index 49bcc509eee509be943cfed990e516ca0810574e..c0626efd43b6ed410bb8dcdc86fc4e477b60c74f 100644 (file)
--- a/src/regexec.c
+++ b/src/regexec.c
@@ -3235,18 +3235,25 @@ forward_search_range(regex_t* reg, const UChar* str, const UChar* end, UChar* s,
     }
     else {
       if (reg->dmax != ONIG_INFINITE_DISTANCE) {
-        *low = p - reg->dmax;
-        if (*low > s) {
-          *low = onigenc_get_right_adjust_char_head_with_prev(reg->enc, s,
-                                          *low, (const UChar** )low_prev);
-          if (low_prev && IS_NULL(*low_prev))
-            *low_prev = onigenc_get_prev_char_head(reg->enc,
-                                                   (pprev ? pprev : s), *low);
+        if (p - str < reg->dmax) {
+          *low = (UChar* )str;
+          if (low_prev)
+            *low_prev = onigenc_get_prev_char_head(reg->enc, str, *low);
         }
         else {
-          if (low_prev)
-            *low_prev = onigenc_get_prev_char_head(reg->enc,
-                                                   (pprev ? pprev : str), *low);
+          *low = p - reg->dmax;
+          if (*low > s) {
+            *low = onigenc_get_right_adjust_char_head_with_prev(reg->enc, s,
+                                                 *low, (const UChar** )low_prev);
+            if (low_prev && IS_NULL(*low_prev))
+              *low_prev = onigenc_get_prev_char_head(reg->enc,
+                                                     (pprev ? pprev : s), *low);
+          }
+          else {
+            if (low_prev)
+              *low_prev = onigenc_get_prev_char_head(reg->enc,
+                                                     (pprev ? pprev : str), *low);
+          }
         }
       }
     }