mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-04 09:59:32 +00:00
![Kees Cook](/assets/img/avatar_default.png)
This converts all remaining cases of the old setup_timer() API into using timer_setup(), where the callback argument is the structure already holding the struct timer_list. These should have no behavioral changes, since they just change which pointer is passed into the callback with the same available pointers after conversion. It handles the following examples, in addition to some other variations. Casting from unsigned long: void my_callback(unsigned long data) { struct something *ptr = (struct something *)data; ... } ... setup_timer(&ptr->my_timer, my_callback, ptr); and forced object casts: void my_callback(struct something *ptr) { ... } ... setup_timer(&ptr->my_timer, my_callback, (unsigned long)ptr); become: void my_callback(struct timer_list *t) { struct something *ptr = from_timer(ptr, t, my_timer); ... } ... timer_setup(&ptr->my_timer, my_callback, 0); Direct function assignments: void my_callback(unsigned long data) { struct something *ptr = (struct something *)data; ... } ... ptr->my_timer.function = my_callback; have a temporary cast added, along with converting the args: void my_callback(struct timer_list *t) { struct something *ptr = from_timer(ptr, t, my_timer); ... } ... ptr->my_timer.function = (TIMER_FUNC_TYPE)my_callback; And finally, callbacks without a data assignment: void my_callback(unsigned long data) { ... } ... setup_timer(&ptr->my_timer, my_callback, 0); have their argument renamed to verify they're unused during conversion: void my_callback(struct timer_list *unused) { ... } ... timer_setup(&ptr->my_timer, my_callback, 0); The conversion is done with the following Coccinelle script: spatch --very-quiet --all-includes --include-headers \ -I ./arch/x86/include -I ./arch/x86/include/generated \ -I ./include -I ./arch/x86/include/uapi \ -I ./arch/x86/include/generated/uapi -I ./include/uapi \ -I ./include/generated/uapi --include ./include/linux/kconfig.h \ --dir . \ --cocci-file ~/src/data/timer_setup.cocci @fix_address_of@ expression e; @@ setup_timer( -&(e) +&e , ...) // Update any raw setup_timer() usages that have a NULL callback, but // would otherwise match change_timer_function_usage, since the latter // will update all function assignments done in the face of a NULL // function initialization in setup_timer(). @change_timer_function_usage_NULL@ expression _E; identifier _timer; type _cast_data; @@ ( -setup_timer(&_E->_timer, NULL, _E); +timer_setup(&_E->_timer, NULL, 0); | -setup_timer(&_E->_timer, NULL, (_cast_data)_E); +timer_setup(&_E->_timer, NULL, 0); | -setup_timer(&_E._timer, NULL, &_E); +timer_setup(&_E._timer, NULL, 0); | -setup_timer(&_E._timer, NULL, (_cast_data)&_E); +timer_setup(&_E._timer, NULL, 0); ) @change_timer_function_usage@ expression _E; identifier _timer; struct timer_list _stl; identifier _callback; type _cast_func, _cast_data; @@ ( -setup_timer(&_E->_timer, _callback, _E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, &_callback, _E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, _callback, (_cast_data)_E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, &_callback, (_cast_data)_E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, (_cast_func)_callback, _E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, (_cast_func)&_callback, _E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, (_cast_func)_callback, (_cast_data)_E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, (_cast_func)&_callback, (_cast_data)_E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E._timer, _callback, (_cast_data)_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, _callback, (_cast_data)&_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, &_callback, (_cast_data)_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, &_callback, (_cast_data)&_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, (_cast_func)_callback, (_cast_data)_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, (_cast_func)_callback, (_cast_data)&_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, (_cast_func)&_callback, (_cast_data)_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, (_cast_func)&_callback, (_cast_data)&_E); +timer_setup(&_E._timer, _callback, 0); | _E->_timer@_stl.function = _callback; | _E->_timer@_stl.function = &_callback; | _E->_timer@_stl.function = (_cast_func)_callback; | _E->_timer@_stl.function = (_cast_func)&_callback; | _E._timer@_stl.function = _callback; | _E._timer@_stl.function = &_callback; | _E._timer@_stl.function = (_cast_func)_callback; | _E._timer@_stl.function = (_cast_func)&_callback; ) // callback(unsigned long arg) @change_callback_handle_cast depends on change_timer_function_usage@ identifier change_timer_function_usage._callback; identifier change_timer_function_usage._timer; type _origtype; identifier _origarg; type _handletype; identifier _handle; @@ void _callback( -_origtype _origarg +struct timer_list *t ) { ( ... when != _origarg _handletype *_handle = -(_handletype *)_origarg; +from_timer(_handle, t, _timer); ... when != _origarg | ... when != _origarg _handletype *_handle = -(void *)_origarg; +from_timer(_handle, t, _timer); ... when != _origarg | ... when != _origarg _handletype *_handle; ... when != _handle _handle = -(_handletype *)_origarg; +from_timer(_handle, t, _timer); ... when != _origarg | ... when != _origarg _handletype *_handle; ... when != _handle _handle = -(void *)_origarg; +from_timer(_handle, t, _timer); ... when != _origarg ) } // callback(unsigned long arg) without existing variable @change_callback_handle_cast_no_arg depends on change_timer_function_usage && !change_callback_handle_cast@ identifier change_timer_function_usage._callback; identifier change_timer_function_usage._timer; type _origtype; identifier _origarg; type _handletype; @@ void _callback( -_origtype _origarg +struct timer_list *t ) { + _handletype *_origarg = from_timer(_origarg, t, _timer); + ... when != _origarg - (_handletype *)_origarg + _origarg ... when != _origarg } // Avoid already converted callbacks. @match_callback_converted depends on change_timer_function_usage && !change_callback_handle_cast && !change_callback_handle_cast_no_arg@ identifier change_timer_function_usage._callback; identifier t; @@ void _callback(struct timer_list *t) { ... } // callback(struct something *handle) @change_callback_handle_arg depends on change_timer_function_usage && !match_callback_converted && !change_callback_handle_cast && !change_callback_handle_cast_no_arg@ identifier change_timer_function_usage._callback; identifier change_timer_function_usage._timer; type _handletype; identifier _handle; @@ void _callback( -_handletype *_handle +struct timer_list *t ) { + _handletype *_handle = from_timer(_handle, t, _timer); ... } // If change_callback_handle_arg ran on an empty function, remove // the added handler. @unchange_callback_handle_arg depends on change_timer_function_usage && change_callback_handle_arg@ identifier change_timer_function_usage._callback; identifier change_timer_function_usage._timer; type _handletype; identifier _handle; identifier t; @@ void _callback(struct timer_list *t) { - _handletype *_handle = from_timer(_handle, t, _timer); } // We only want to refactor the setup_timer() data argument if we've found // the matching callback. This undoes changes in change_timer_function_usage. @unchange_timer_function_usage depends on change_timer_function_usage && !change_callback_handle_cast && !change_callback_handle_cast_no_arg && !change_callback_handle_arg@ expression change_timer_function_usage._E; identifier change_timer_function_usage._timer; identifier change_timer_function_usage._callback; type change_timer_function_usage._cast_data; @@ ( -timer_setup(&_E->_timer, _callback, 0); +setup_timer(&_E->_timer, _callback, (_cast_data)_E); | -timer_setup(&_E._timer, _callback, 0); +setup_timer(&_E._timer, _callback, (_cast_data)&_E); ) // If we fixed a callback from a .function assignment, fix the // assignment cast now. @change_timer_function_assignment depends on change_timer_function_usage && (change_callback_handle_cast || change_callback_handle_cast_no_arg || change_callback_handle_arg)@ expression change_timer_function_usage._E; identifier change_timer_function_usage._timer; identifier change_timer_function_usage._callback; type _cast_func; typedef TIMER_FUNC_TYPE; @@ ( _E->_timer.function = -_callback +(TIMER_FUNC_TYPE)_callback ; | _E->_timer.function = -&_callback +(TIMER_FUNC_TYPE)_callback ; | _E->_timer.function = -(_cast_func)_callback; +(TIMER_FUNC_TYPE)_callback ; | _E->_timer.function = -(_cast_func)&_callback +(TIMER_FUNC_TYPE)_callback ; | _E._timer.function = -_callback +(TIMER_FUNC_TYPE)_callback ; | _E._timer.function = -&_callback; +(TIMER_FUNC_TYPE)_callback ; | _E._timer.function = -(_cast_func)_callback +(TIMER_FUNC_TYPE)_callback ; | _E._timer.function = -(_cast_func)&_callback +(TIMER_FUNC_TYPE)_callback ; ) // Sometimes timer functions are called directly. Replace matched args. @change_timer_function_calls depends on change_timer_function_usage && (change_callback_handle_cast || change_callback_handle_cast_no_arg || change_callback_handle_arg)@ expression _E; identifier change_timer_function_usage._timer; identifier change_timer_function_usage._callback; type _cast_data; @@ _callback( ( -(_cast_data)_E +&_E->_timer | -(_cast_data)&_E +&_E._timer | -_E +&_E->_timer ) ) // If a timer has been configured without a data argument, it can be // converted without regard to the callback argument, since it is unused. @match_timer_function_unused_data@ expression _E; identifier _timer; identifier _callback; @@ ( -setup_timer(&_E->_timer, _callback, 0); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, _callback, 0L); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, _callback, 0UL); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E._timer, _callback, 0); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, _callback, 0L); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, _callback, 0UL); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_timer, _callback, 0); +timer_setup(&_timer, _callback, 0); | -setup_timer(&_timer, _callback, 0L); +timer_setup(&_timer, _callback, 0); | -setup_timer(&_timer, _callback, 0UL); +timer_setup(&_timer, _callback, 0); | -setup_timer(_timer, _callback, 0); +timer_setup(_timer, _callback, 0); | -setup_timer(_timer, _callback, 0L); +timer_setup(_timer, _callback, 0); | -setup_timer(_timer, _callback, 0UL); +timer_setup(_timer, _callback, 0); ) @change_callback_unused_data depends on match_timer_function_unused_data@ identifier match_timer_function_unused_data._callback; type _origtype; identifier _origarg; @@ void _callback( -_origtype _origarg +struct timer_list *unused ) { ... when != _origarg } Signed-off-by: Kees Cook <keescook@chromium.org>
316 lines
7.6 KiB
C
316 lines
7.6 KiB
C
/*
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* linux/net/netfilter/xt_IDLETIMER.c
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*
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* Netfilter module to trigger a timer when packet matches.
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* After timer expires a kevent will be sent.
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*
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* Copyright (C) 2004, 2010 Nokia Corporation
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* Written by Timo Teras <ext-timo.teras@nokia.com>
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*
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* Converted to x_tables and reworked for upstream inclusion
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* by Luciano Coelho <luciano.coelho@nokia.com>
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*
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* Contact: Luciano Coelho <luciano.coelho@nokia.com>
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* version 2 as published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
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* 02110-1301 USA
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*/
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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#include <linux/module.h>
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#include <linux/timer.h>
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#include <linux/list.h>
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#include <linux/mutex.h>
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#include <linux/netfilter.h>
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#include <linux/netfilter/x_tables.h>
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#include <linux/netfilter/xt_IDLETIMER.h>
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#include <linux/kdev_t.h>
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#include <linux/kobject.h>
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#include <linux/workqueue.h>
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#include <linux/sysfs.h>
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struct idletimer_tg_attr {
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struct attribute attr;
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ssize_t (*show)(struct kobject *kobj,
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struct attribute *attr, char *buf);
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};
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struct idletimer_tg {
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struct list_head entry;
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struct timer_list timer;
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struct work_struct work;
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struct kobject *kobj;
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struct idletimer_tg_attr attr;
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unsigned int refcnt;
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};
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static LIST_HEAD(idletimer_tg_list);
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static DEFINE_MUTEX(list_mutex);
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static struct kobject *idletimer_tg_kobj;
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static
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struct idletimer_tg *__idletimer_tg_find_by_label(const char *label)
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{
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struct idletimer_tg *entry;
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BUG_ON(!label);
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list_for_each_entry(entry, &idletimer_tg_list, entry) {
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if (!strcmp(label, entry->attr.attr.name))
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return entry;
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}
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return NULL;
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}
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static ssize_t idletimer_tg_show(struct kobject *kobj, struct attribute *attr,
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char *buf)
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{
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struct idletimer_tg *timer;
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unsigned long expires = 0;
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mutex_lock(&list_mutex);
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timer = __idletimer_tg_find_by_label(attr->name);
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if (timer)
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expires = timer->timer.expires;
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mutex_unlock(&list_mutex);
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if (time_after(expires, jiffies))
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return sprintf(buf, "%u\n",
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jiffies_to_msecs(expires - jiffies) / 1000);
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return sprintf(buf, "0\n");
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}
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static void idletimer_tg_work(struct work_struct *work)
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{
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struct idletimer_tg *timer = container_of(work, struct idletimer_tg,
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work);
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sysfs_notify(idletimer_tg_kobj, NULL, timer->attr.attr.name);
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}
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static void idletimer_tg_expired(struct timer_list *t)
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{
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struct idletimer_tg *timer = from_timer(timer, t, timer);
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pr_debug("timer %s expired\n", timer->attr.attr.name);
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schedule_work(&timer->work);
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}
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static int idletimer_tg_create(struct idletimer_tg_info *info)
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{
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int ret;
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info->timer = kmalloc(sizeof(*info->timer), GFP_KERNEL);
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if (!info->timer) {
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ret = -ENOMEM;
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goto out;
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}
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sysfs_attr_init(&info->timer->attr.attr);
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info->timer->attr.attr.name = kstrdup(info->label, GFP_KERNEL);
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if (!info->timer->attr.attr.name) {
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ret = -ENOMEM;
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goto out_free_timer;
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}
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info->timer->attr.attr.mode = S_IRUGO;
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info->timer->attr.show = idletimer_tg_show;
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ret = sysfs_create_file(idletimer_tg_kobj, &info->timer->attr.attr);
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if (ret < 0) {
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pr_debug("couldn't add file to sysfs");
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goto out_free_attr;
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}
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list_add(&info->timer->entry, &idletimer_tg_list);
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timer_setup(&info->timer->timer, idletimer_tg_expired, 0);
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info->timer->refcnt = 1;
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mod_timer(&info->timer->timer,
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msecs_to_jiffies(info->timeout * 1000) + jiffies);
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INIT_WORK(&info->timer->work, idletimer_tg_work);
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return 0;
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out_free_attr:
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kfree(info->timer->attr.attr.name);
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out_free_timer:
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kfree(info->timer);
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out:
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return ret;
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}
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/*
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* The actual xt_tables plugin.
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*/
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static unsigned int idletimer_tg_target(struct sk_buff *skb,
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const struct xt_action_param *par)
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{
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const struct idletimer_tg_info *info = par->targinfo;
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pr_debug("resetting timer %s, timeout period %u\n",
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info->label, info->timeout);
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BUG_ON(!info->timer);
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mod_timer(&info->timer->timer,
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msecs_to_jiffies(info->timeout * 1000) + jiffies);
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return XT_CONTINUE;
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}
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static int idletimer_tg_checkentry(const struct xt_tgchk_param *par)
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{
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struct idletimer_tg_info *info = par->targinfo;
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int ret;
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pr_debug("checkentry targinfo%s\n", info->label);
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if (info->timeout == 0) {
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pr_debug("timeout value is zero\n");
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return -EINVAL;
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}
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if (info->label[0] == '\0' ||
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strnlen(info->label,
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MAX_IDLETIMER_LABEL_SIZE) == MAX_IDLETIMER_LABEL_SIZE) {
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pr_debug("label is empty or not nul-terminated\n");
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return -EINVAL;
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}
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mutex_lock(&list_mutex);
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info->timer = __idletimer_tg_find_by_label(info->label);
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if (info->timer) {
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info->timer->refcnt++;
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mod_timer(&info->timer->timer,
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msecs_to_jiffies(info->timeout * 1000) + jiffies);
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pr_debug("increased refcnt of timer %s to %u\n",
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info->label, info->timer->refcnt);
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} else {
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ret = idletimer_tg_create(info);
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if (ret < 0) {
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pr_debug("failed to create timer\n");
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mutex_unlock(&list_mutex);
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return ret;
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}
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}
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mutex_unlock(&list_mutex);
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return 0;
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}
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static void idletimer_tg_destroy(const struct xt_tgdtor_param *par)
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{
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const struct idletimer_tg_info *info = par->targinfo;
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pr_debug("destroy targinfo %s\n", info->label);
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mutex_lock(&list_mutex);
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if (--info->timer->refcnt == 0) {
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pr_debug("deleting timer %s\n", info->label);
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list_del(&info->timer->entry);
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del_timer_sync(&info->timer->timer);
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cancel_work_sync(&info->timer->work);
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sysfs_remove_file(idletimer_tg_kobj, &info->timer->attr.attr);
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kfree(info->timer->attr.attr.name);
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kfree(info->timer);
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} else {
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pr_debug("decreased refcnt of timer %s to %u\n",
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info->label, info->timer->refcnt);
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}
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mutex_unlock(&list_mutex);
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}
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static struct xt_target idletimer_tg __read_mostly = {
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.name = "IDLETIMER",
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.family = NFPROTO_UNSPEC,
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.target = idletimer_tg_target,
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.targetsize = sizeof(struct idletimer_tg_info),
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.checkentry = idletimer_tg_checkentry,
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.destroy = idletimer_tg_destroy,
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.me = THIS_MODULE,
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};
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static struct class *idletimer_tg_class;
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static struct device *idletimer_tg_device;
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static int __init idletimer_tg_init(void)
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{
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int err;
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idletimer_tg_class = class_create(THIS_MODULE, "xt_idletimer");
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err = PTR_ERR(idletimer_tg_class);
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if (IS_ERR(idletimer_tg_class)) {
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pr_debug("couldn't register device class\n");
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goto out;
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}
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idletimer_tg_device = device_create(idletimer_tg_class, NULL,
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MKDEV(0, 0), NULL, "timers");
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err = PTR_ERR(idletimer_tg_device);
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if (IS_ERR(idletimer_tg_device)) {
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pr_debug("couldn't register system device\n");
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goto out_class;
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}
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idletimer_tg_kobj = &idletimer_tg_device->kobj;
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err = xt_register_target(&idletimer_tg);
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if (err < 0) {
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pr_debug("couldn't register xt target\n");
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goto out_dev;
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}
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return 0;
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out_dev:
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device_destroy(idletimer_tg_class, MKDEV(0, 0));
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out_class:
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class_destroy(idletimer_tg_class);
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out:
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return err;
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}
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static void __exit idletimer_tg_exit(void)
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{
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xt_unregister_target(&idletimer_tg);
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device_destroy(idletimer_tg_class, MKDEV(0, 0));
|
|
class_destroy(idletimer_tg_class);
|
|
}
|
|
|
|
module_init(idletimer_tg_init);
|
|
module_exit(idletimer_tg_exit);
|
|
|
|
MODULE_AUTHOR("Timo Teras <ext-timo.teras@nokia.com>");
|
|
MODULE_AUTHOR("Luciano Coelho <luciano.coelho@nokia.com>");
|
|
MODULE_DESCRIPTION("Xtables: idle time monitor");
|
|
MODULE_LICENSE("GPL v2");
|
|
MODULE_ALIAS("ipt_IDLETIMER");
|
|
MODULE_ALIAS("ip6t_IDLETIMER");
|