[Fix] Fix memory allocation in fstring

diff --git a/src/libutil/fstring.c b/src/libutil/fstring.c
index 87773bd944bfbac866af32c908eb23db0b743563..dcec28895cedacdf0a8e7f94e30e491c719b9a98 100644 (file)
--- a/src/libutil/fstring.c
+++ b/src/libutil/fstring.c
@@ -66,7 +66,7 @@ rspamd_fstring_new_init (const gchar *init, gsize len)
 rspamd_fstring_t *
 rspamd_fstring_assign (rspamd_fstring_t *str, const gchar *init, gsize len)
 {
-       gsize avail = str->allocated;
+       gsize avail = fstravail (str);
 
        if (avail < len) {
                str = rspamd_fstring_grow (str, len);
@@ -93,7 +93,7 @@ rspamd_fstring_grow (rspamd_fstring_t *str, gsize needed_len)
        gsize newlen;
        gpointer nptr;
 
-       newlen = str->len + needed_len;
+       newlen = str->allocated;
 
        /*
         * Stop exponential grow at some point, since it might be slow for the
@@ -106,6 +106,20 @@ rspamd_fstring_grow (rspamd_fstring_t *str, gsize needed_len)
                newlen += max_grow;
        }
 
+       /*
+        * Check for overflow
+        */
+       if (newlen <= str->len + needed_len) {
+               newlen = str->len + needed_len;
+
+               if (newlen < max_grow) {
+                       newlen *= 2;
+               }
+               else {
+                       newlen += max_grow;
+               }
+       }
+
        nptr = realloc (str, newlen + sizeof (*str));
 
        if (nptr == NULL) {