[src/trunk]: src/sys/kern Validate the return value of cfprint functions befo...

[thorpej <thorpej%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/c653f01d61e7
branches:  trunk
changeset: 1020936:c653f01d61e7
user:      thorpej <thorpej%NetBSD.org@localhost>
date:      Wed Apr 28 03:21:57 2021 +0000

description:
Validate the return value of cfprint functions before using it to
index the msgs[] array.  Use designated initializers to initialize
msgs[].

diffstat:

 sys/kern/subr_autoconf.c |  17 +++++++++++++----
 1 files changed, 13 insertions(+), 4 deletions(-)

diffs (45 lines):

diff -r e8e110fd73ac -r c653f01d61e7 sys/kern/subr_autoconf.c
--- a/sys/kern/subr_autoconf.c  Wed Apr 28 02:28:05 2021 +0000
+++ b/sys/kern/subr_autoconf.c  Wed Apr 28 03:21:57 2021 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: subr_autoconf.c,v 1.279 2021/04/27 14:48:28 thorpej Exp $ */
+/* $NetBSD: subr_autoconf.c,v 1.280 2021/04/28 03:21:57 thorpej Exp $ */
 
 /*
  * Copyright (c) 1996, 2000 Christopher G. Demetriou
@@ -79,7 +79,7 @@
 #define        __SUBR_AUTOCONF_PRIVATE /* see <sys/device.h> */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: subr_autoconf.c,v 1.279 2021/04/27 14:48:28 thorpej Exp $");
+__KERNEL_RCSID(0, "$NetBSD: subr_autoconf.c,v 1.280 2021/04/28 03:21:57 thorpej Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_ddb.h"
@@ -1214,7 +1214,11 @@
        return m.match;
 }
 
-static const char * const msgs[3] = { "", " not configured\n", " unsupported\n" };
+static const char * const msgs[] = {
+[QUIET]                =       "",
+[UNCONF]       =       " not configured\n",
+[UNSUPP]       =       " unsupported\n",
+};
 
 /*
  * The given `aux' argument describes a device that has been found
@@ -1242,7 +1246,12 @@
        if (print) {
                if (config_do_twiddle && cold)
                        twiddle();
-               aprint_normal("%s", msgs[(*print)(aux, device_xname(parent))]);
+
+               const int pret = (*print)(aux, device_xname(parent));
+               KASSERT(pret >= 0);
+               KASSERT(pret < __arraycount(msgs));
+               KASSERT(msgs[pret] != NULL);
+               aprint_normal("%s", msgs[pret]);
        }
 
        /*