[src/trunk]: src/sys/compat/common Test for valid interface for ...

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

details:   https://anonhg.NetBSD.org/src/rev/7c30f59dcd6b
branches:  trunk
changeset: 318474:7c30f59dcd6b
user:      roy <roy%NetBSD.org@localhost>
date:      Thu Apr 26 08:11:18 2018 +0000
description:
Test for valid interface for ioctls that demand it.

Thanks to Robert Swindells for the patch.

diffstat:

 sys/compat/common/uipc_syscalls_50.c |  20 +++++++++++++++-----
 1 files changed, 15 insertions(+), 5 deletions(-)

diffs (49 lines):

diff -r f4ea5420d9f8 -r 7c30f59dcd6b sys/compat/common/uipc_syscalls_50.c
--- a/sys/compat/common/uipc_syscalls_50.c      Thu Apr 26 07:48:21 2018 +0000
+++ b/sys/compat/common/uipc_syscalls_50.c      Thu Apr 26 08:11:18 2018 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: uipc_syscalls_50.c,v 1.4 2018/04/12 18:50:13 christos Exp $    */
+/*     $NetBSD: uipc_syscalls_50.c,v 1.5 2018/04/26 08:11:18 roy Exp $ */
 
 /*-
  * Copyright (c) 2008 The NetBSD Foundation, Inc.
@@ -37,7 +37,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: uipc_syscalls_50.c,v 1.4 2018/04/12 18:50:13 christos Exp $");
+__KERNEL_RCSID(0, "$NetBSD: uipc_syscalls_50.c,v 1.5 2018/04/26 08:11:18 roy Exp $");
 
 #include <sys/param.h>
 #include <sys/kernel.h>
@@ -63,10 +63,19 @@
        struct ifnet *ifp;
        int error;
 
-       ifp = ifunit(ifdr->ifdr_name);
-       if (ifp == NULL)
-               return ENXIO;
+       /* Validate arguments. */
+       switch (cmd) {
+       case SIOCGIFDATA:
+       case SIOCZIFDATA:
+               ifp = ifunit(ifdr->ifdr_name);
+               if (ifp == NULL)
+                       return ENXIO;
+               break;
+       default:
+               return ENOSYS;
+       }
 
+       /* Do work. */
        switch (cmd) {
        case SIOCGIFDATA:
                ifdatan2o(&ifdr->ifdr_data, &ifp->if_data);
@@ -91,6 +100,7 @@
                return 0;
 
        default:
+               /* Impossible due to above validation, but makes gcc happy. */
                return ENOSYS;
        }
 }