Take more care to ensure name_to_string() always returns a proper

string. Don't rely on GPT partition name containing a terminating
zero or the reserved bytes beyond gp_name being properly
initialized to zero.

diff --git a/sbin/fdisk/gpt.c b/sbin/fdisk/gpt.c
index 65e7e8e..8e8badf 100644 (file)
--- a/sbin/fdisk/gpt.c
+++ b/sbin/fdisk/gpt.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: gpt.c,v 1.92 2023/06/19 23:11:19 krw Exp $    */
+/*     $OpenBSD: gpt.c,v 1.93 2023/06/20 11:52:08 krw Exp $    */
 /*
  * Copyright (c) 2015 Markus Muller <mmu@grummel.net>
  * Copyright (c) 2015 Kenneth R Westerback <krw@openbsd.org>
@@ -77,10 +77,9 @@ name_to_string(const unsigned int pn)
        static char             name[GPTPARTNAMESIZE + 1];
        unsigned int            i;
 
-       memset(name, 0, sizeof(name));
-
-       for (i = 0; i < sizeof(name) && gp[pn].gp_name[i] != 0; i++)
+       for (i = 0; i < GPTPARTNAMESIZE && gp[pn].gp_name[i] != 0; i++)
                name[i] = letoh16(gp[pn].gp_name[i]) & 0x7F;
+       name[i] = '\0';
 
        return name;
 }