diff --git a/fs/jfs/jfs_filsys.h b/fs/jfs/jfs_filsys.h
index 1e899298f7f0..b5d702df7111 100644
--- a/fs/jfs/jfs_filsys.h
+++ b/fs/jfs/jfs_filsys.h
@@ -268,5 +268,6 @@
 				 * fsck() must be run to repair
 				 */
 #define	FM_EXTENDFS 0x00000008	/* file system extendfs() in progress */
+#define	FM_STATE_MAX 0x0000000f	/* max value of s_state */
 
 #endif				/* _H_JFS_FILSYS */
diff --git a/fs/jfs/jfs_mount.c b/fs/jfs/jfs_mount.c
index eb8b9e233d73..616de103dccc 100644
--- a/fs/jfs/jfs_mount.c
+++ b/fs/jfs/jfs_mount.c
@@ -36,6 +36,7 @@
 
 #include <linux/fs.h>
 #include <linux/buffer_head.h>
+#include <linux/log2.h>
 
 #include "jfs_incore.h"
 #include "jfs_filsys.h"
@@ -365,6 +366,15 @@ static int chkSuper(struct super_block *sb)
 	sbi->bsize = bsize;
 	sbi->l2bsize = le16_to_cpu(j_sb->s_l2bsize);
 
+	/* check some fields for possible corruption */
+	if (sbi->l2bsize != ilog2((u32)bsize) ||
+	    j_sb->pad != 0 ||
+	    le32_to_cpu(j_sb->s_state) > FM_STATE_MAX) {
+		rc = -EINVAL;
+		jfs_err("jfs_mount: Mount Failure: superblock is corrupt!");
+		goto out;
+	}
+
 	/*
 	 * For now, ignore s_pbsize, l2bfactor.  All I/O going through buffer
 	 * cache.