Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 0c93b7d8 authored by Al Viro's avatar Al Viro
Browse files

bpf: reject invalid names right in ->lookup() 



... and other methods won't see them at all

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent 798434bd

kernel/bpf/inode.c

+8 −29
Original line number Diff line number Diff line
@@ -119,18 +119,10 @@ static int bpf_inode_type(const struct inode *inode, enum bpf_type *type) 
	return 0;

}



static bool bpf_dname_reserved(const struct dentry *dentry)

{

	return strchr(dentry->d_name.name, '.');

}



static int bpf_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)

{

	struct inode *inode;



	if (bpf_dname_reserved(dentry))

		return -EPERM;



	inode = bpf_get_inode(dir->i_sb, dir, mode | S_IFDIR);

	if (IS_ERR(inode))

		return PTR_ERR(inode);
@@ -152,9 +144,6 @@ static int bpf_mkobj_ops(struct inode *dir, struct dentry *dentry, 
{

	struct inode *inode;



	if (bpf_dname_reserved(dentry))

		return -EPERM;



	inode = bpf_get_inode(dir->i_sb, dir, mode | S_IFREG);

	if (IS_ERR(inode))

		return PTR_ERR(inode);
@@ -187,31 +176,21 @@ static int bpf_mkobj(struct inode *dir, struct dentry *dentry, umode_t mode, 
	}

}



static int bpf_link(struct dentry *old_dentry, struct inode *dir,

		    struct dentry *new_dentry)

static struct dentry *

bpf_lookup(struct inode *dir, struct dentry *dentry, unsigned flags)

{

	if (bpf_dname_reserved(new_dentry))

		return -EPERM;



	return simple_link(old_dentry, dir, new_dentry);

}



static int bpf_rename(struct inode *old_dir, struct dentry *old_dentry,

		      struct inode *new_dir, struct dentry *new_dentry)

{

	if (bpf_dname_reserved(new_dentry))

		return -EPERM;



	return simple_rename(old_dir, old_dentry, new_dir, new_dentry);

	if (strchr(dentry->d_name.name, '.'))

		return ERR_PTR(-EPERM);

	return simple_lookup(dir, dentry, flags);

}



static const struct inode_operations bpf_dir_iops = {

	.lookup		= simple_lookup,

	.lookup		= bpf_lookup,

	.mknod		= bpf_mkobj,

	.mkdir		= bpf_mkdir,

	.rmdir		= simple_rmdir,

	.rename		= bpf_rename,

	.link		= bpf_link,

	.rename		= simple_rename,

	.link		= simple_link,

	.unlink		= simple_unlink,

};