[PATCH] large dev_t - second series (9/15)

beginning of fs side work:
	* new helpers - old_valid_dev(), old_encode_dev() and old_decode_dev()
	* old_valid_dev() checks if dev_t value is OK for old filesystems
(i.e. both major and minor are below 256).
	* old_valid_dev() calls are added in ->mknod() instances that care
about dev_t values (disk-backed and network ones).
	* old_encode_dev() and old_decode_dev() convert dev_t -> u16
and u16 -> dev_t resp; currently these are no-ops, places that use current
formar (minor in bits 0--7, major in bits 8--15) will switch to these before
we widen dev_t.

fs/cifs/dir.c

@@ -265,6 +265,9 @@ int cifs_mknod(struct inode *inode, struct dentry *direntry, int mode, dev_t dev
 	char *full_path = NULL;
 	struct inode * newinode = NULL;
 
+	if (!old_valid_dev(device_number))
+		return -EINVAL;
+
 	xid = GetXid();
 
 	cifs_sb = CIFS_SB(inode->i_sb);

fs/coda/dir.c

@@ -242,6 +242,9 @@ static int coda_mknod(struct inode *dir, struct dentry *de, int mode, dev_t rdev
 	if ( coda_hasmknod == 0 )
 		return -EIO;
 
+	if (!old_valid_dev(rdev))
+		return -EINVAL;
+
 	lock_kernel();
 	coda_vfs_stat.create++;
 

fs/ext2/namei.c

@@ -139,8 +139,14 @@ static int ext2_create (struct inode * dir, struct dentry * dentry, int mode, st
 
 static int ext2_mknod (struct inode * dir, struct dentry *dentry, int mode, dev_t rdev)
 {
-	struct inode * inode = ext2_new_inode (dir, mode);
-	int err = PTR_ERR(inode);
+	struct inode * inode;
+	int err;
+
+	if (!old_valid_dev(rdev))
+		return -EINVAL;
+
+	inode = ext2_new_inode (dir, mode);
+	err = PTR_ERR(inode);
 	if (!IS_ERR(inode)) {
 		init_special_inode(inode, inode->i_mode, rdev);
 #ifdef CONFIG_EXT2_FS_XATTR

fs/ext3/namei.c

@@ -1659,6 +1659,9 @@ static int ext3_mknod (struct inode * dir, struct dentry *dentry,
 	struct inode *inode;
 	int err;
 
+	if (!old_valid_dev(rdev))
+		return -EINVAL;
+
 	handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS +
 			 		EXT3_INDEX_EXTRA_TRANS_BLOCKS + 3);
 	if (IS_ERR(handle))

fs/hpfs/namei.c

@@ -194,6 +194,8 @@ int hpfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t rdev)
 	int err;
 	if ((err = hpfs_chk_name((char *)name, &len))) return err==-ENOENT ? -EINVAL : err;
 	if (hpfs_sb(dir->i_sb)->sb_eas < 2) return -EPERM;
+	if (!old_valid_dev(rdev))
+		return -EINVAL;
 	lock_kernel();
 	if (!(fnode = hpfs_alloc_fnode(dir->i_sb, hpfs_i(dir)->i_dno, &fno, &bh))) goto bail;
 	memset(&dee, 0, sizeof dee);

fs/intermezzo/dir.c

@@ -726,6 +726,9 @@ static int presto_mknod(struct inode * dir, struct dentry * dentry, int mode, de
         struct dentry *parent = dentry->d_parent;
         struct lento_vfs_context info;
 
+	if (!old_valid_dev(rdev))
+		return -EINVAL;
+
         ENTRY;
         error = presto_check_set_fsdata(dentry);
         if ( error ) {

fs/jffs/inode-v23.c

@@ -1086,6 +1086,8 @@ jffs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t rdev)
 
 	D1(printk("***jffs_mknod()\n"));
 
+	if (!old_valid_dev(rdev))
+		return -EINVAL;
 	lock_kernel();
 	dir_f = (struct jffs_file *)dir->u.generic_ip;
 	c = dir_f->c;

fs/jffs2/dir.c

@@ -594,6 +594,9 @@ static int jffs2_mknod (struct inode *dir_i, struct dentry *dentry, int mode, mk
 	uint32_t writtenlen;
 	int ret;
 
+	if (!old_valid_dev(rdev))
+		return -EINVAL;
+
 	ri = jffs2_alloc_raw_inode();
 	if (!ri)
 		return -ENOMEM;

fs/jfs/namei.c

@@ -1311,6 +1311,9 @@ int jfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t rdev)
 	tid_t tid;
 	struct tblock *tblk;
 
+	if (!old_valid_dev(rdev))
+		return -EINVAL;
+
 	jfs_info("jfs_mknod: %s", dentry->d_name.name);
 
 	if ((rc = get_UCSname(&dname, dentry, JFS_SBI(dir->i_sb)->nls_tab)))

fs/libfs.c

@@ -3,6 +3,7 @@
  *	Library for filesystems writers.
  */
 
+#include <linux/module.h>
 #include <linux/pagemap.h>
 #include <linux/mount.h>
 #include <linux/vfs.h>
@@ -428,3 +429,22 @@ void simple_release_fs(struct vfsmount **mount, int *count)
 	spin_unlock(&pin_fs_lock);
 	mntput(mnt);
 }
+
+/* acceptable for old filesystems */
+int old_valid_dev(dev_t dev)
+{
+	return MAJOR(dev) < 256 && MINOR(dev) < 256;
+}
+EXPORT_SYMBOL(old_valid_dev);
+
+u16 old_encode_dev(dev_t dev)
+{
+	return (MAJOR(dev) << 8) | MINOR(dev);
+}
+EXPORT_SYMBOL(old_encode_dev);
+
+dev_t old_decode_dev(u16 val)
+{
+	return MKDEV((val >> 8) & 255, val & 255);
+}
+EXPORT_SYMBOL(old_decode_dev);

fs/minix/namei.c

@@ -78,7 +78,12 @@ static struct dentry *minix_lookup(struct inode * dir, struct dentry *dentry, st
 static int minix_mknod(struct inode * dir, struct dentry *dentry, int mode, dev_t rdev)
 {
 	int error;
-	struct inode * inode = minix_new_inode(dir, &error);
+	struct inode *inode;
+
+	if (!old_valid_dev(rdev))
+		return -EINVAL;
+
+	inode = minix_new_inode(dir, &error);
 
 	if (inode) {
 		inode->i_mode = mode;

fs/ncpfs/dir.c

@@ -1170,6 +1170,8 @@ static int ncp_rename(struct inode *old_dir, struct dentry *old_dentry,
 static int ncp_mknod(struct inode * dir, struct dentry *dentry,
 		     int mode, dev_t rdev)
 {
+	if (!old_valid_dev(rdev))
+		return -EINVAL;
 	if (ncp_is_nfs_extras(NCP_SERVER(dir), NCP_FINFO(dir)->volNumber)) {
 		DPRINTK(KERN_DEBUG "ncp_mknod: mode = 0%o\n", mode);
 		return ncp_create_new(dir, dentry, mode, rdev, 0);

fs/nfs/dir.c

@@ -859,6 +859,9 @@ nfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t rdev)
 	dfprintk(VFS, "NFS: mknod(%s/%ld, %s\n", dir->i_sb->s_id,
 		dir->i_ino, dentry->d_name.name);
 
+	if (!old_valid_dev(rdev))
+		return -EINVAL;
+
 	attr.ia_mode = mode;
 	attr.ia_valid = ATTR_MODE;
 

fs/reiserfs/namei.c

@@ -613,6 +613,9 @@ static int reiserfs_mknod (struct inode * dir, struct dentry *dentry, int mode,
     struct reiserfs_transaction_handle th ;
     int jbegin_count = JOURNAL_PER_BALANCE_CNT * 3; 
 
+    if (!old_valid_dev(rdev))
+	return -EINVAL;
+
     if (!(inode = new_inode(dir->i_sb))) {
 	return -ENOMEM ;
     }

fs/smbfs/dir.c

@@ -661,6 +661,9 @@ smb_make_node(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
 	attr.ia_uid = current->euid;
 	attr.ia_gid = current->egid;
 
+	if (!old_valid_dev(dev))
+		return -EINVAL;
+
 	smb_invalid_dir_cache(dir);
 	error = smb_proc_setattr_unix(dentry, &attr, MAJOR(dev), MINOR(dev));
 	if (!error) {

fs/sysv/namei.c

@@ -85,8 +85,14 @@ static struct dentry *sysv_lookup(struct inode * dir, struct dentry * dentry, st
 
 static int sysv_mknod(struct inode * dir, struct dentry * dentry, int mode, dev_t rdev)
 {
-	struct inode * inode = sysv_new_inode(dir, mode);
-	int err = PTR_ERR(inode);
+	struct inode * inode;
+	int err;
+
+	if (!old_valid_dev(rdev))
+		return -EINVAL;
+
+	inode = sysv_new_inode(dir, mode);
+	err = PTR_ERR(inode);
 
 	if (!IS_ERR(inode)) {
 		sysv_set_inode(inode, rdev);

fs/udf/namei.c

@@ -677,6 +677,9 @@ static int udf_mknod(struct inode * dir, struct dentry * dentry, int mode, dev_t
 	int err;
 	struct fileIdentDesc cfi, *fi;
 
+	if (!old_valid_dev(rdev))
+		return -EINVAL;
+
 	lock_kernel();
 	err = -EIO;
 	inode = udf_new_inode(dir, mode, &err);

fs/ufs/namei.c

@@ -111,7 +111,10 @@ static int ufs_create (struct inode * dir, struct dentry * dentry, int mode,
 
 static int ufs_mknod (struct inode * dir, struct dentry *dentry, int mode, dev_t rdev)
 {
-	struct inode * inode = ufs_new_inode(dir, mode);
+	struct inode * inode;
+	if (!old_valid_dev(rdev))
+		return -EINVAL;
+	inode = ufs_new_inode(dir, mode);
 	int err = PTR_ERR(inode);
 	if (!IS_ERR(inode)) {
 		init_special_inode(inode, mode, rdev);

fs/xfs/linux/xfs_iops.c

@@ -113,6 +113,9 @@ linvfs_mknod(
 	xattr_exists_t	test_default_acl = _ACL_DEFAULT_EXISTS;
 	int		error;
 
+	if (!old_valid_dev(rdev))
+		return -EINVAL;
+
 	if (test_default_acl && test_default_acl(dvp)) {
 		if (!_ACL_ALLOC(default_acl))
 			return -ENOMEM;

include/linux/fs.h

@@ -1389,6 +1389,9 @@ struct tree_descr { char *name; struct file_operations *ops; int mode; };
 extern int simple_fill_super(struct super_block *, int, struct tree_descr *);
 extern int simple_pin_fs(char *name, struct vfsmount **mount, int *count);
 extern void simple_release_fs(struct vfsmount **mount, int *count);
+extern int old_valid_dev(dev_t);
+extern u16 old_encode_dev(dev_t);
+extern dev_t old_decode_dev(u16);
 
 extern int inode_change_ok(struct inode *, struct iattr *);
 extern int inode_setattr(struct inode *, struct iattr *);