From 99b76233803beab302123d243eea9e41149804f3 Mon Sep 17 00:00:00 2001 From: Alexey Dobriyan Date: Wed, 25 Mar 2009 22:48:06 +0300 Subject: 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 --- net/sunrpc/cache.c | 4 ---- 1 file changed, 4 deletions(-) (limited to 'net/sunrpc/cache.c') diff --git a/net/sunrpc/cache.c b/net/sunrpc/cache.c index 4735caad26ed..20029a79a5de 100644 --- a/net/sunrpc/cache.c +++ b/net/sunrpc/cache.c @@ -313,7 +313,6 @@ static int create_cache_proc_entries(struct cache_detail *cd) cd->proc_ent = proc_mkdir(cd->name, proc_net_rpc); if (cd->proc_ent == NULL) goto out_nomem; - cd->proc_ent->owner = cd->owner; cd->channel_ent = cd->content_ent = NULL; p = proc_create_data("flush", S_IFREG|S_IRUSR|S_IWUSR, @@ -321,7 +320,6 @@ static int create_cache_proc_entries(struct cache_detail *cd) cd->flush_ent = p; if (p == NULL) goto out_nomem; - p->owner = cd->owner; if (cd->cache_request || cd->cache_parse) { p = proc_create_data("channel", S_IFREG|S_IRUSR|S_IWUSR, @@ -329,7 +327,6 @@ static int create_cache_proc_entries(struct cache_detail *cd) cd->channel_ent = p; if (p == NULL) goto out_nomem; - p->owner = cd->owner; } if (cd->cache_show) { p = proc_create_data("content", S_IFREG|S_IRUSR|S_IWUSR, @@ -337,7 +334,6 @@ static int create_cache_proc_entries(struct cache_detail *cd) cd->content_ent = p; if (p == NULL) goto out_nomem; - p->owner = cd->owner; } return 0; out_nomem: -- cgit v1.2.3-59-g8ed1b