From b660d0485efeff743c72f1be2185832de8477a24 Mon Sep 17 00:00:00 2001 From: Adam Nielsen Date: Fri, 9 Apr 2010 16:51:40 +0200 Subject: netfilter: xt_LED: add refcounts to LED target Add reference counting to the netfilter LED target, to fix errors when multiple rules point to the same target ("LED trigger already exists"). Signed-off-by: Adam Nielsen Signed-off-by: Patrick McHardy --- net/netfilter/xt_LED.c | 69 +++++++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 63 insertions(+), 6 deletions(-) (limited to 'net/netfilter') diff --git a/net/netfilter/xt_LED.c b/net/netfilter/xt_LED.c index efcf56db23e8..bd102c77d1f0 100644 --- a/net/netfilter/xt_LED.c +++ b/net/netfilter/xt_LED.c @@ -31,12 +31,18 @@ MODULE_LICENSE("GPL"); MODULE_AUTHOR("Adam Nielsen "); MODULE_DESCRIPTION("Xtables: trigger LED devices on packet match"); +static LIST_HEAD(xt_led_triggers); +static DEFINE_MUTEX(xt_led_mutex); + /* * This is declared in here (the kernel module) only, to avoid having these * dependencies in userspace code. This is what xt_led_info.internal_data * points to. */ struct xt_led_info_internal { + struct list_head list; + int refcnt; + char *trigger_id; struct led_trigger netfilter_led_trigger; struct timer_list timer; }; @@ -53,7 +59,7 @@ led_tg(struct sk_buff *skb, const struct xt_target_param *par) */ if ((ledinfo->delay > 0) && ledinfo->always_blink && timer_pending(&ledinternal->timer)) - led_trigger_event(&ledinternal->netfilter_led_trigger,LED_OFF); + led_trigger_event(&ledinternal->netfilter_led_trigger, LED_OFF); led_trigger_event(&ledinternal->netfilter_led_trigger, LED_FULL); @@ -74,12 +80,23 @@ led_tg(struct sk_buff *skb, const struct xt_target_param *par) static void led_timeout_callback(unsigned long data) { - struct xt_led_info *ledinfo = (struct xt_led_info *)data; - struct xt_led_info_internal *ledinternal = ledinfo->internal_data; + struct xt_led_info_internal *ledinternal = (struct xt_led_info_internal *)data; led_trigger_event(&ledinternal->netfilter_led_trigger, LED_OFF); } +static struct xt_led_info_internal *led_trigger_lookup(const char *name) +{ + struct xt_led_info_internal *ledinternal; + + list_for_each_entry(ledinternal, &xt_led_triggers, list) { + if (!strcmp(name, ledinternal->netfilter_led_trigger.name)) { + return ledinternal; + } + } + return NULL; +} + static int led_tg_check(const struct xt_tgchk_param *par) { struct xt_led_info *ledinfo = par->targinfo; @@ -91,11 +108,25 @@ static int led_tg_check(const struct xt_tgchk_param *par) return -EINVAL; } + mutex_lock(&xt_led_mutex); + + ledinternal = led_trigger_lookup(ledinfo->id); + if (ledinternal) { + ledinternal->refcnt++; + goto out; + } + + err = -ENOMEM; ledinternal = kzalloc(sizeof(struct xt_led_info_internal), GFP_KERNEL); if (!ledinternal) - return -ENOMEM; + goto exit_mutex_only; + + ledinternal->trigger_id = kstrdup(ledinfo->id, GFP_KERNEL); + if (!ledinternal->trigger_id) + goto exit_internal_alloc; - ledinternal->netfilter_led_trigger.name = ledinfo->id; + ledinternal->refcnt = 1; + ledinternal->netfilter_led_trigger.name = ledinternal->trigger_id; err = led_trigger_register(&ledinternal->netfilter_led_trigger); if (err) { @@ -108,13 +139,26 @@ static int led_tg_check(const struct xt_tgchk_param *par) /* See if we need to set up a timer */ if (ledinfo->delay > 0) setup_timer(&ledinternal->timer, led_timeout_callback, - (unsigned long)ledinfo); + (unsigned long)ledinternal); + + list_add_tail(&ledinternal->list, &xt_led_triggers); + +out: + mutex_unlock(&xt_led_mutex); ledinfo->internal_data = ledinternal; + return 0; exit_alloc: + kfree(ledinternal->trigger_id); + +exit_internal_alloc: kfree(ledinternal); + +exit_mutex_only: + mutex_unlock(&xt_led_mutex); + return err; } @@ -123,10 +167,23 @@ static void led_tg_destroy(const struct xt_tgdtor_param *par) const struct xt_led_info *ledinfo = par->targinfo; struct xt_led_info_internal *ledinternal = ledinfo->internal_data; + mutex_lock(&xt_led_mutex); + + if (--ledinternal->refcnt) { + mutex_unlock(&xt_led_mutex); + return; + } + + list_del(&ledinternal->list); + if (ledinfo->delay > 0) del_timer_sync(&ledinternal->timer); led_trigger_unregister(&ledinternal->netfilter_led_trigger); + + mutex_unlock(&xt_led_mutex); + + kfree(ledinternal->trigger_id); kfree(ledinternal); } -- cgit v1.2.3