linux-sg2042/net/can
Alexey Dobriyan 99b7623380 proc 2/2: remove struct proc_dir_entry::owner
Setting ->owner as done currently (pde->owner = THIS_MODULE) is racy
as correctly noted at bug #12454. Someone can lookup entry with NULL
->owner, thus not pinning enything, and release it later resulting
in module refcount underflow.

We can keep ->owner and supply it at registration time like ->proc_fops
and ->data.

But this leaves ->owner as easy-manipulative field (just one C assignment)
and somebody will forget to unpin previous/pin current module when
switching ->owner. ->proc_fops is declared as "const" which should give
some thoughts.

->read_proc/->write_proc were just fixed to not require ->owner for
protection.

rmmod'ed directories will be empty and return "." and ".." -- no harm.
And directories with tricky enough readdir and lookup shouldn't be modular.
We definitely don't want such modular code.

Removing ->owner will also make PDE smaller.

So, let's nuke it.

Kudos to Jeff Layton for reminding about this, let's say, oversight.

http://bugzilla.kernel.org/show_bug.cgi?id=12454

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
2009-03-31 01:14:44 +04:00
..
Kconfig [CAN]: Add virtual CAN netdevice driver 2008-01-28 14:54:12 -08:00
Makefile [CAN]: Add broadcast manager (bcm) protocol 2008-01-28 14:54:11 -08:00
af_can.c can: remove some pointless conditionals before kfree_skb() 2009-02-26 23:07:35 -08:00
af_can.h [CAN]: Add PF_CAN core module 2008-01-28 14:54:10 -08:00
bcm.c proc 2/2: remove struct proc_dir_entry::owner 2009-03-31 01:14:44 +04:00
proc.c proc 2/2: remove struct proc_dir_entry::owner 2009-03-31 01:14:44 +04:00
raw.c ip: support for TX timestamps on UDP and RAW sockets 2009-02-15 22:43:38 -08:00