Smack: fix smack_new_inode bogosities

In January of 2012 Al Viro pointed out three bits of code that
he titled "new_inode_smack bogosities". This patch repairs these
errors.

1. smack_sb_kern_mount() included a NULL check that is impossible.
   The check and NULL case are removed.
2. smack_kb_kern_mount() included pointless locking. The locking is
   removed. Since this is the only place that lock was used the lock
   is removed from the superblock_smack structure.
3. smk_fill_super() incorrectly and unnecessarily set the Smack label
   for the smackfs root inode. The assignment has been removed.

Targeted for git://gitorious.org/smack-next/kernel.git

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>

3 files changed, 2 insertions, 8 deletions

diff --git a/security/smack/smack.h b/security/smack/smack.h
index cc361b8f3d13..76feb31eb823 100644
--- a/security/smack/smack.h
+++ b/security/smack/smack.h
@@ -43,7 +43,6 @@ struct superblock_smack {
         char            *smk_hat;
         char            *smk_default;
         int             smk_initialized;
-        spinlock_t      smk_sblock;     /* for initialization */
 };
 
 struct socket_smack {
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index ee0bb5735f35..29bb4e7fa5e8 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -251,7 +251,6 @@ static int smack_sb_alloc_security(struct super_block *sb)
         sbsp->smk_floor = smack_known_floor.smk_known;
         sbsp->smk_hat = smack_known_hat.smk_known;
         sbsp->smk_initialized = 0;
-        spin_lock_init(&sbsp->smk_sblock);
 
         sb->s_security = sbsp;
 
@@ -332,13 +331,10 @@ static int smack_sb_kern_mount(struct super_block *sb, int flags, void *data)
         char *commap;
         char *nsp;
 
-        spin_lock(&sp->smk_sblock);
-        if (sp->smk_initialized != 0) {
-                spin_unlock(&sp->smk_sblock);
+        if (sp->smk_initialized != 0)
                 return 0;
-        }
+
         sp->smk_initialized = 1;
-        spin_unlock(&sp->smk_sblock);
 
         for (op = data; op != NULL; op = commap) {
                 commap = strchr(op, ',');
diff --git a/security/smack/smackfs.c b/security/smack/smackfs.c
index 1810c9a4ed48..3686db7e2c6b 100644
--- a/security/smack/smackfs.c
+++ b/security/smack/smackfs.c
@@ -2051,7 +2051,6 @@ static int smk_fill_super(struct super_block *sb, void *data, int silent)
         }
 
         root_inode = sb->s_root->d_inode;
-        root_inode->i_security = new_inode_smack(smack_known_floor.smk_known);
 
         return 0;
 }