path: root/net/can
diff options
authorAlexey Dobriyan <adobriyan@gmail.com>2009-03-25 22:48:06 +0300
committerAlexey Dobriyan <adobriyan@gmail.com>2009-03-31 01:14:44 +0400
commit99b76233803beab302123d243eea9e41149804f3 (patch)
tree398178210fe66845ccd6fa4258ba762a87e023ad /net/can
parent3dec7f59c370c7b58184d63293c3dc984d475840 (diff)
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>
Diffstat (limited to 'net/can')
2 files changed, 0 insertions, 6 deletions
diff --git a/net/can/bcm.c b/net/can/bcm.c
index b7c7d465113..95d7f32643a 100644
--- a/net/can/bcm.c
+++ b/net/can/bcm.c
@@ -1604,10 +1604,6 @@ static int __init bcm_module_init(void)
/* create /proc/net/can-bcm directory */
proc_dir = proc_mkdir("can-bcm", init_net.proc_net);
- if (proc_dir)
- proc_dir->owner = THIS_MODULE;
return 0;
diff --git a/net/can/proc.c b/net/can/proc.c
index 520fef5e539..1463653dbe3 100644
--- a/net/can/proc.c
+++ b/net/can/proc.c
@@ -473,8 +473,6 @@ void can_init_proc(void)
- can_dir->owner = THIS_MODULE;
/* own procfs entries from the AF_CAN core */
pde_version = can_create_proc_readentry(CAN_PROC_VERSION, 0644,
can_proc_read_version, NULL);