possible bug in VFS ?

[Signal9]

 When i tried bestcrypt (a crypto-fs) with the new 2.4.12 kernel, i got a 
ooops when mounting a device. The oops was in this line:

(in bcrypt-0.8-6/mod/bc_dev24.c)

               root = current->fs->rootmnt;
               list_for_each(ptr, &root->mnt_list) {
                        mnt = list_entry(ptr, struct vfsmount, mnt_list);
                        sb = mnt ? mnt->mnt_sb : NULL;
                         if (NULL != sb && dev == sb->s_dev) <============
                                        mntget(mnt);
                }

 The oops was a pointer dereference to 0x9. I added some printk's to see the 
values of the pointers. I did see that in the last 'struct vfsmount' linked 
inside root->mnt_list, the mnt_sb field is '0x1', so when it tries to access 
sb->sb_dev it dereferences a pointer to 0x9. The field mnt_devname was NULL.

 żIs this a bug in the kernel or a bug in bestcrypt?

 Cheers,

 - Doing

PD: Please send replies with CC to me, since i'm not subscribed to the list :)