anon_inode: set S_IFREG on the anon_inode

anon_inode_mkinode() sets inode->i_mode = S_IRUSR | S_IWUSR;  This means
that (inode->i_mode & S_IFMT) == 0.  This trips up some SELinux code that
needs to determine if a given inode is a regular file, a directory, etc.
The easiest solution is to just make sure that the anon_inode also sets
S_IFREG.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/anon_inodes.c

@@ -205,7 +205,7 @@ static struct inode *anon_inode_mkinode(void)
 	 * that it already _is_ on the dirty list.
 	 */
 	inode->i_state = I_DIRTY;
-	inode->i_mode = S_IRUSR | S_IWUSR;
+	inode->i_mode = S_IFREG | S_IRUSR | S_IWUSR;
 	inode->i_uid = current_fsuid();
 	inode->i_gid = current_fsgid();
 	inode->i_flags |= S_PRIVATE;