[src/trunk]: src/lib/librumpuser Avoid buffer overflow

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

details:   https://anonhg.NetBSD.org/src/rev/576a7c34c4a2
branches:  trunk
changeset: 932379:576a7c34c4a2
user:      kamil <kamil%NetBSD.org@localhost>
date:      Wed May 06 07:25:26 2020 +0000

description:
Avoid buffer overflow

Disable the offending code.

OK by kre@

diffstat:

 lib/librumpuser/rumpuser_sp.c |  12 ++++++++++--
 1 files changed, 10 insertions(+), 2 deletions(-)

diffs (46 lines):

diff -r e915d4f9763c -r 576a7c34c4a2 lib/librumpuser/rumpuser_sp.c
--- a/lib/librumpuser/rumpuser_sp.c     Wed May 06 05:14:27 2020 +0000
+++ b/lib/librumpuser/rumpuser_sp.c     Wed May 06 07:25:26 2020 +0000
@@ -1,4 +1,4 @@
-/*      $NetBSD: rumpuser_sp.c,v 1.75 2020/03/24 14:56:31 kre Exp $    */
+/*      $NetBSD: rumpuser_sp.c,v 1.76 2020/05/06 07:25:26 kamil Exp $  */
 
 /*
  * Copyright (c) 2010, 2011 Antti Kantee.  All Rights Reserved.
@@ -37,7 +37,7 @@
 #include "rumpuser_port.h"
 
 #if !defined(lint)
-__RCSID("$NetBSD: rumpuser_sp.c,v 1.75 2020/03/24 14:56:31 kre Exp $");
+__RCSID("$NetBSD: rumpuser_sp.c,v 1.76 2020/05/06 07:25:26 kamil Exp $");
 #endif /* !lint */
 
 #include <sys/types.h>
@@ -715,9 +715,13 @@
         * very much).  proceed with exec.
         */
 
+#if 0 /* XXX triggers buffer overflow */
        /* ensure comm is 0-terminated */
        /* TODO: make sure it contains sensible chars? */
        comm[commlen] = '\0';
+#else
+       (void)commlen;
+#endif
 
        lwproc_switch(spc->spc_mainlwp);
        lwproc_execnotify(comm);
@@ -979,9 +983,13 @@
                        char *comm = (char *)spc->spc_buf;
                        size_t commlen = spc->spc_hdr.rsp_len - HDRSZ;
 
+#if 0 /* XXX triggers buffer overflow */
                        /* ensure it's 0-terminated */
                        /* XXX make sure it contains sensible chars? */
                        comm[commlen] = '\0';
+#else
+                       (void)commlen;
+#endif
 
                        /* make sure we fork off of proc1 */
                        _DIAGASSERT(lwproc_curlwp() == NULL);