Never trust snprintf return value

main/fopen_wrappers.c

@@ -568,6 +568,9 @@ static FILE *php_fopen_url_wrap_http(const char *path, char *mode, int options,
 		len = snprintf(hdr_line, sizeof(hdr_line),
 					   "Host: %s\r\n", resource->host);
 	}
+	if(len > sizeof(hdr_line) - 1) {
+		len = sizeof(hdr_line) - 1;
+	}
 	if (len > 0) {
 		SOCK_WRITE(hdr_line, *socketd);
 	}

main/main.c

@@ -317,6 +317,9 @@ PHPAPI int php_printf(const char *format, ...)
 
 	va_start(args, format);
 	size = vsnprintf(buffer, sizeof(buffer), format, args);
+	if(size > sizeof(buffer) - 1) {
+		size = sizeof(buffer) - 1;
+	}
 	ret = PHPWRITE(buffer, size);
 	va_end(args);