diff options
author | Alexey Dobriyan <adobriyan@gmail.com> | 2009-03-25 15:48:06 -0400 |
---|---|---|
committer | Alexey Dobriyan <adobriyan@gmail.com> | 2009-03-30 17:14:44 -0400 |
commit | 99b76233803beab302123d243eea9e41149804f3 (patch) | |
tree | 398178210fe66845ccd6fa4258ba762a87e023ad /net/sunrpc/stats.c | |
parent | 3dec7f59c370c7b58184d63293c3dc984d475840 (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/sunrpc/stats.c')
-rw-r--r-- | net/sunrpc/stats.c | 10 |
1 files changed, 2 insertions, 8 deletions
diff --git a/net/sunrpc/stats.c b/net/sunrpc/stats.c index 085372ef4feb..1ef6e46d9da2 100644 --- a/net/sunrpc/stats.c +++ b/net/sunrpc/stats.c | |||
@@ -262,14 +262,8 @@ void | |||
262 | rpc_proc_init(void) | 262 | rpc_proc_init(void) |
263 | { | 263 | { |
264 | dprintk("RPC: registering /proc/net/rpc\n"); | 264 | dprintk("RPC: registering /proc/net/rpc\n"); |
265 | if (!proc_net_rpc) { | 265 | if (!proc_net_rpc) |
266 | struct proc_dir_entry *ent; | 266 | proc_net_rpc = proc_mkdir("rpc", init_net.proc_net); |
267 | ent = proc_mkdir("rpc", init_net.proc_net); | ||
268 | if (ent) { | ||
269 | ent->owner = THIS_MODULE; | ||
270 | proc_net_rpc = ent; | ||
271 | } | ||
272 | } | ||
273 | } | 267 | } |
274 | 268 | ||
275 | void | 269 | void |