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Commit fdb36673 authored by NeilBrown's avatar NeilBrown Committed by Linus Torvalds
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[PATCH] knfsd: Make ext3 reject filehandles referring to invalid inode number 



Inodes earlier than the 'first' inode (e.g.  journal, resize) should be
rejected early - except the root inode.  Also inode numbers that are too
big should be rejected early.

[akpm@osdl.org: cleanup]
Signed-off-by: default avatarNeil Brown <neilb@suse.de>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent ecaff756

fs/ext3/super.c

+42 −0
Original line number Diff line number Diff line
@@ -554,6 +554,47 @@ static int ext3_show_options(struct seq_file *seq, struct vfsmount *vfs) 
	return 0;

}





static struct dentry *ext3_get_dentry(struct super_block *sb, void *vobjp)

{

	__u32 *objp = vobjp;

	unsigned long ino = objp[0];

	__u32 generation = objp[1];

	struct inode *inode;

	struct dentry *result;



	if (ino < EXT3_FIRST_INO(sb) && ino != EXT3_ROOT_INO)

		return ERR_PTR(-ESTALE);

	if (ino > le32_to_cpu(EXT3_SB(sb)->s_es->s_inodes_count))

		return ERR_PTR(-ESTALE);



	/* iget isn't really right if the inode is currently unallocated!!

	 *

	 * ext3_read_inode will return a bad_inode if the inode had been

	 * deleted, so we should be safe.

	 *

	 * Currently we don't know the generation for parent directory, so

	 * a generation of 0 means "accept any"

	 */

	inode = iget(sb, ino);

	if (inode == NULL)

		return ERR_PTR(-ENOMEM);

	if (is_bad_inode(inode) ||

	    (generation && inode->i_generation != generation)) {

		iput(inode);

		return ERR_PTR(-ESTALE);

	}

	/* now to find a dentry.

	 * If possible, get a well-connected one

	 */

	result = d_alloc_anon(inode);

	if (!result) {

		iput(inode);

		return ERR_PTR(-ENOMEM);

	}

	return result;

}



#ifdef CONFIG_QUOTA

#define QTYPE2NAME(t) ((t)==USRQUOTA?"user":"group")

#define QTYPE2MOPT(on, t) ((t)==USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
@@ -622,6 +663,7 @@ static struct super_operations ext3_sops = { 


static struct export_operations ext3_export_ops = {

	.get_parent = ext3_get_parent,

	.get_dentry = ext3_get_dentry,

};



enum {