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>

diff --git a/src/volser/vol_split.c b/src/volser/vol_split.c
index 17e3805138eff9cf97e552b6e099ff6be5c7ad5b..1be53c2b4d80118ab6b0f951ca2155a87699c0b4 100644 (file)
--- 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);