• Ian Kent's avatar
    cifs - check S_AUTOMOUNT in revalidate · 936ad909
    Ian Kent authored
    When revalidating a dentry, if the inode wasn't known to be a dfs
    entry when the dentry was instantiated, such as when created via
    ->readdir(), the DCACHE_NEED_AUTOMOUNT flag needs to be set on the
    dentry in ->d_revalidate().
    
    The false return from cifs_d_revalidate(), due to the inode now
    being marked with the S_AUTOMOUNT flag, might not invalidate the
    dentry if there is a concurrent unlazy path walk. This is because
    the dentry reference count will be at least 2 in this case causing
    d_invalidate() to return EBUSY. So the asumption that the dentry
    will be discarded then correctly instantiated via ->lookup() might
    not hold.
    Signed-off-by: default avatarIan Kent <raven@themaw.net>
    Reviewed-by: default avatarJeff Layton <jlayton@redhat.com>
    Cc: Steve French <smfrench@gmail.com>
    Cc: linux-cifs@vger.kernel.org
    Signed-off-by: default avatarSteve French <sfrench@us.ibm.com>
    936ad909
dir.c 20.5 KB