From 3af6beea4b03bd4dd62b23a6a0df149037b456c0 Mon Sep 17 00:00:00 2001
From: Garrett Wollman <wollman@csail.mit.edu>
Date: Sun, 15 Jul 2012 15:13:55 -0400
Subject: [PATCH] volser: don't derefernce null pointer in copyVnodes()

split_volume() can call copyVnodes() with parVnode == NULL, so guard
the one reference to parVnode (a memcpy()) to avoid a fault.

Change-Id: I631a78bcfa6a7a465e997a6714849ca0d2d86f86
Reviewed-on: http://gerrit.openafs.org/7769
Reviewed-by: Derrick Brashear <shadow@dementix.org>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
---
 src/volser/vol_split.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/volser/vol_split.c b/src/volser/vol_split.c
index 17e3805138..1be53c2b4d 100644
--- a/src/volser/vol_split.c
+++ b/src/volser/vol_split.c
@@ -375,7 +375,8 @@ afs_int32 copyVnodes(struct Msg *m, Volume *vol, Volume *newvol,
 		    code = EIO;
 		    goto Bad_Copy;
 	        }
-	        memcpy(parVnode, vnode, sizeof(struct VnodeDiskObject));
+		if (parVnode != NULL)
+		    memcpy(parVnode, vnode, sizeof(struct VnodeDiskObject));
 	    }
 	    if (e->flag & NEEDED && e->vN != where) {
 	        VNDISK_GET_LEN(size, vnode);