hi folks, i'm trying to hook a function of the VFS, in order to hide a file in the filesystem
(actually a directory, containing some sensitive stuff)
i've read some papers that i found on google, even rootkit sources such as adore-ng
however they seem not to work under recent kernels

here is what i'm trying to do:

struct file *f;

f = filp_open(root_fs,O_RDONLY,0); /* root_fs is declared as "/" */

/* backup the original readdir */
original_readdir = f->f_op->readdir;

/*the hook */
f->f_op->readdir = my_readdir;

now the error from make...

error: assignment of read-only location *f->f_op?

i can't figure out the problem, it is a GCC bug or what?
any clue on ??

Tnks.