syslinux_parse: make print_escaped actually stop before `to'

The only current user is mboot.c32 which unfortunately is not covered
by regression tests.

diff --git a/grub-core/lib/syslinux_parse.c b/grub-core/lib/syslinux_parse.c
index 153260b5410ee3b01cf123160c1d8d49519da72a..ba71a483100799e1eca2a960a12773237a036132 100644 (file)
--- a/grub-core/lib/syslinux_parse.c
+++ b/grub-core/lib/syslinux_parse.c
@@ -772,7 +772,7 @@ print_escaped (struct output_buffer *outbuf,
   if (err)
     return err;
   outbuf->buf[outbuf->ptr++] = '\'';
-  for (ptr = from; *ptr; ptr++)
+  for (ptr = from; *ptr && ptr < to; ptr++)
     {
       if (*ptr == '\'')
        {