SELinux: no BUG_ON(!ss_initialized) in selinux_clone_mnt_opts

The Fedora installer actually makes multiple NFS mounts before it loads
selinux policy.  The code in selinux_clone_mnt_opts() assumed that the
init process would always be loading policy before NFS was up and
running.  It might be possible to hit this in a diskless environment as
well, I'm not sure.  There is no need to BUG_ON() in this situation
since we can safely continue given the circumstances.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>

diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 1bf2543..33af321 100644 (file)
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -755,9 +755,18 @@ static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
        int set_context =       (oldsbsec->flags & CONTEXT_MNT);
        int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
 
-       /* we can't error, we can't save the info, this shouldn't get called
-        * this early in the boot process. */
-       BUG_ON(!ss_initialized);
+       /*
+        * if the parent was able to be mounted it clearly had no special lsm
+        * mount options.  thus we can safely put this sb on the list and deal
+        * with it later
+        */
+       if (!ss_initialized) {
+               spin_lock(&sb_security_lock);
+               if (list_empty(&newsbsec->list))
+                       list_add(&newsbsec->list, &superblock_security_head);
+               spin_unlock(&sb_security_lock);
+               return;
+       }
 
        /* how can we clone if the old one wasn't set up?? */
        BUG_ON(!oldsbsec->initialized);