OpenAFS Master Repository branch, openafs-stable-1_6_x, updated. openafs-stable-1_6_11pre1-10-gc98fb96

[Gerrit Code Review]

The following commit has been merged in the openafs-stable-1_6_x branch:
commit c98fb960b9d9a4cab37bec7fa341f01dad60d14e
Author: Andrew Deason <adeason@sinenomine.net>
Date:   Mon Dec 1 10:23:23 2014 -0600

    LINUX: Avoid mvid NULL deref in check_bad_parent
    
    check_bad_parent dereferences vcp->mvid, assuming it is not NULL (vcp
    is a root vcache here, so mvid refers to the parent fid). However, in
    some situations, vcp->mvid can be NULL.
    
    When we first afs_GetVCache the fid, we try to set mvid by setting
    mvid to the 'dotdot' structure in the volume struct. But we get that
    volume struct from afs_GetVolume, which can fail (at the very least,
    this can fail on network failure when looking up vldb information). If
    it fails, then we do not set the mvid parent. On future lookups for
    the fid, afs_GetVCache will return early for a fastpath, if the vcache
    is already in memory. So, mvid will never get set in such a situation.
    
    We also set the mvid parent fid in afs_lookup if we resolved a
    mountpoint to the root vcache. However, this is skipped if CMValid is
    not set on the vcache, so if CMValid is cleared right after resolving
    the mountpoint (say, perhaps done by some other thread e.g. a callback
    break or other reasons), then the mvid parent fid will not be set.
    
    To avoid crashing in these situations, if vcp->mvid is NULL in
    check_bad_parent, don't check the mvid, and assume it does not match
    (since we don't know what it is).
    
    This is a 1.6-only change. On the master branch, the problem is
    addressed by commit 69e84bd8a2ccc6065c3a06b7239c855207b92e4d .
    
    Change-Id: I3550cf5a01811ede17d74770161326667a6e8628
    Reviewed-on: http://gerrit.openafs.org/11616
    Tested-by: BuildBot <buildbot@rampaginggeek.com>
    Reviewed-by: Chas Williams - CONTRACTOR <chas@cmf.nrl.navy.mil>
    Reviewed-by: Perry Ruiter <pruiter@sinenomine.net>
    Reviewed-by: Stephan Wiesand <stephan.wiesand@desy.de>

 src/afs/LINUX/osi_vnodeops.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

-- 
OpenAFS Master Repository