Fix memcpy null UB in phar

Author: nikic

ext/phar/phar_internal.h

@@ -511,8 +511,10 @@ static inline void phar_set_inode(phar_entry_info *entry) /* {{{ */
 
 tmp_len = MIN(MAXPATHLEN, entry->filename_len + entry->phar->fname_len);
 
-len1 = MIN(entry->phar->fname_len, tmp_len);
-memcpy(tmp, entry->phar->fname, len1);
+if (entry->phar->fname) {
+len1 = MIN(entry->phar->fname_len, tmp_len);
+memcpy(tmp, entry->phar->fname, len1);
+}
 
 len2 = MIN(tmp_len - len1, entry->filename_len);
 memcpy(tmp + len1, entry->filename, len2);