Description: Fix fortify abort when LTO is enabled
 Usually the Strncpy call in tftp_send_error cannot be inlined, but if
 LTO is enabled GCC will inline it all the way to a strncpy call. This
 call is subject to fortification checks and will always fail because
 `th_msg` has zero size.
 .
 Fix by using memcpy instead. memcpy has weaker fortification rules
 for structure members so it won't abort.
 .
 See: https://sourceware.org/pipermail/libc-alpha/2012-April/028823.html
 And: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=52944
Author: James Cowgill <jcowgill@debian.org>
Bug-Ubuntu: https://bugs.launchpad.net/ubuntu/+source/atftp/+bug/1989816
Forwarded: https://sourceforge.net/p/atftp/bugs/14/
---
This patch header follows DEP-3: http://dep.debian.net/deps/dep3/
--- a/tftp_io.c
+++ b/tftp_io.c
@@ -168,9 +168,9 @@ int tftp_send_error(int socket, struct s
           return ERR;
      tftphdr->th_opcode = htons(ERROR);
      tftphdr->th_code = htons(err_code);
-     Strncpy(tftphdr->th_msg, tftp_errmsg[err_code], buffer_size - 4);
 
      size = 4 + strlen(tftp_errmsg[err_code]) + 1;
+     memcpy(tftphdr->th_msg, tftp_errmsg[err_code], size - 4);
 
      result = sendto(socket, tftphdr, size, 0, (struct sockaddr *)sa,
                      sizeof(*sa));