[src/trunk]: src/usr.sbin/makemandb Don't index outside the mdocs array of fu...

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

details:   https://anonhg.NetBSD.org/src/rev/bd587255234b
branches:  trunk
changeset: 366667:bd587255234b
user:      skrll <skrll%NetBSD.org@localhost>
date:      Mon Jun 06 07:41:23 2022 +0000

description:
Don't index outside the mdocs array of function pointers.  Analysis and
suggested fixes from Tom Lane.  I played it safe and went with (my
variation of) the minimal fix.

port-hppa/56118: sporadic app crashes in HPPA -current

diffstat:

 usr.sbin/makemandb/makemandb.c |  25 ++++++++++++++-----------
 1 files changed, 14 insertions(+), 11 deletions(-)

diffs (46 lines):

diff -r 225485bd3e26 -r bd587255234b usr.sbin/makemandb/makemandb.c
--- a/usr.sbin/makemandb/makemandb.c    Mon Jun 06 07:22:31 2022 +0000
+++ b/usr.sbin/makemandb/makemandb.c    Mon Jun 06 07:41:23 2022 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: makemandb.c,v 1.62 2022/04/06 03:23:38 gutteridge Exp $        */
+/*     $NetBSD: makemandb.c,v 1.63 2022/06/06 07:41:23 skrll Exp $     */
 /*
  * Copyright (c) 2011 Abhinav Upadhyay <er.abhinav.upadhyay%gmail.com@localhost>
  * Copyright (c) 2011 Kristaps Dzonsons <kristaps%bsd.lv@localhost>
@@ -17,7 +17,7 @@
  */
 
 #include <sys/cdefs.h>
-__RCSID("$NetBSD: makemandb.c,v 1.62 2022/04/06 03:23:38 gutteridge Exp $");
+__RCSID("$NetBSD: makemandb.c,v 1.63 2022/06/06 07:41:23 skrll Exp $");
 
 #include <sys/stat.h>
 #include <sys/types.h>
@@ -1078,15 +1078,18 @@
 
        if (n->type == ROFFT_TEXT) {
                mdoc_parse_section(n->sec, n->string, rec);
-       } else if (mdocs[n->tok] == pmdoc_Xr) {
-               /*
-                * When encountering other inline macros,
-                * call pmdoc_macro_handler.
-                */
-               pmdoc_macro_handler(n, rec, MDOC_Xr);
-               xr_found = 1;
-       } else if (mdocs[n->tok] == pmdoc_Pp) {
-               pmdoc_macro_handler(n, rec, MDOC_Pp);
+       } else if (n->tok >= MDOC_Dd && n->tok < MDOC_MAX) {
+               const int tok_idx = n->tok - MDOC_Dd;
+               if (mdocs[tok_idx] == pmdoc_Xr) {
+                       /*
+                       * When encountering other inline macros,
+                       * call pmdoc_macro_handler.
+                       */
+                       pmdoc_macro_handler(n, rec, MDOC_Xr);
+                       xr_found = 1;
+               } else if (mdocs[tok_idx] == pmdoc_Pp) {
+                       pmdoc_macro_handler(n, rec, MDOC_Pp);
+               }
        }
 
        /*