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>

1 files changed, 12 insertions, 3 deletions

diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 1bf2543ea942..33af321f647b 100644
--- 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);