[src/trunk]: src/sys/dev/pci fix crash by NULL pointer dereferencing I get ev...

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

details:   https://anonhg.NetBSD.org/src/rev/afa224384b68
branches:  trunk
changeset: 765709:afa224384b68
user:      cegger <cegger%NetBSD.org@localhost>
date:      Fri Jun 03 09:51:40 2011 +0000

description:
fix crash by NULL pointer dereferencing I get everytime
right after this message:

bge0: discarding oversize frame (len=-4)

diffstat:

 sys/dev/pci/if_bge.c |  9 +++++++--
 1 files changed, 7 insertions(+), 2 deletions(-)

diffs (30 lines):

diff -r 64e7faa0e1bb -r afa224384b68 sys/dev/pci/if_bge.c
--- a/sys/dev/pci/if_bge.c      Fri Jun 03 09:15:02 2011 +0000
+++ b/sys/dev/pci/if_bge.c      Fri Jun 03 09:51:40 2011 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: if_bge.c,v 1.196 2011/05/22 08:15:20 mrg Exp $ */
+/*     $NetBSD: if_bge.c,v 1.197 2011/06/03 09:51:40 cegger Exp $      */
 
 /*
  * Copyright (c) 2001 Wind River Systems
@@ -79,7 +79,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_bge.c,v 1.196 2011/05/22 08:15:20 mrg Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_bge.c,v 1.197 2011/06/03 09:51:40 cegger Exp $");
 
 #include "vlan.h"
 #include "rnd.h"
@@ -3406,6 +3406,11 @@
                        stdcnt++;
                        dmamap = sc->bge_cdata.bge_rx_std_map[rxidx];
                        sc->bge_cdata.bge_rx_std_map[rxidx] = 0;
+                       if (dmamap == NULL) {
+                               ifp->if_ierrors++;
+                               bge_newbuf_std(sc, sc->bge_std, m, dmamap);
+                               continue;
+                       }
                        bus_dmamap_sync(sc->bge_dmatag, dmamap, 0,
                            dmamap->dm_mapsize, BUS_DMASYNC_POSTREAD);
                        bus_dmamap_unload(sc->bge_dmatag, dmamap);