diff --git a/fs/autofs4/autofs_i.h b/fs/autofs4/autofs_i.h
index 4737615f0eaa..ce696d6c4641 100644
--- a/fs/autofs4/autofs_i.h
+++ b/fs/autofs4/autofs_i.h
@@ -26,6 +26,7 @@
 #include <linux/list.h>
 #include <linux/completion.h>
 #include <asm/current.h>
+#include <linux/magic.h>
 
 /* This is the range of ioctl() numbers we claim as ours */
 #define AUTOFS_IOC_FIRST     AUTOFS_IOC_READY
@@ -124,7 +125,8 @@ struct autofs_sb_info {
 
 static inline struct autofs_sb_info *autofs4_sbi(struct super_block *sb)
 {
-	return (struct autofs_sb_info *)(sb->s_fs_info);
+	return sb->s_magic != AUTOFS_SUPER_MAGIC ?
+		NULL : (struct autofs_sb_info *)(sb->s_fs_info);
 }
 
 static inline struct autofs_info *autofs4_dentry_ino(struct dentry *dentry)
diff --git a/fs/autofs4/inode.c b/fs/autofs4/inode.c
index 09e7d68dff02..3c7e727612fa 100644
--- a/fs/autofs4/inode.c
+++ b/fs/autofs4/inode.c
@@ -14,7 +14,6 @@
 #include <linux/pagemap.h>
 #include <linux/parser.h>
 #include <linux/bitops.h>
-#include <linux/magic.h>
 #include "autofs_i.h"
 #include <linux/module.h>