From aff26e2faa782e196f28b86d04b093fd3bae1ffb Mon Sep 17 00:00:00 2001 From: Krzysztof Halasa Date: Mon, 19 May 2008 19:11:08 +0200 Subject: [PATCH] WAN: protect Cisco HDLC state changes with a spinlock. MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Signed-off-by: Krzysztof Hałasa Signed-off-by: Jeff Garzik --- drivers/net/wan/hdlc_cisco.c | 82 +++++++++++++++++++++--------------- 1 file changed, 49 insertions(+), 33 deletions(-) diff --git a/drivers/net/wan/hdlc_cisco.c b/drivers/net/wan/hdlc_cisco.c index 7133c688cf20..762d21c1c703 100644 --- a/drivers/net/wan/hdlc_cisco.c +++ b/drivers/net/wan/hdlc_cisco.c @@ -56,6 +56,7 @@ struct cisco_state { cisco_proto settings; struct timer_list timer; + spinlock_t lock; unsigned long last_poll; int up; int request_sent; @@ -158,6 +159,7 @@ static int cisco_rx(struct sk_buff *skb) { struct net_device *dev = skb->dev; hdlc_device *hdlc = dev_to_hdlc(dev); + struct cisco_state *st = state(hdlc); struct hdlc_header *data = (struct hdlc_header*)skb->data; struct cisco_packet *cisco_data; struct in_device *in_dev; @@ -220,11 +222,12 @@ static int cisco_rx(struct sk_buff *skb) goto rx_error; case CISCO_KEEPALIVE_REQ: - state(hdlc)->rxseq = ntohl(cisco_data->par1); - if (state(hdlc)->request_sent && - ntohl(cisco_data->par2) == state(hdlc)->txseq) { - state(hdlc)->last_poll = jiffies; - if (!state(hdlc)->up) { + spin_lock(&st->lock); + st->rxseq = ntohl(cisco_data->par1); + if (st->request_sent && + ntohl(cisco_data->par2) == st->txseq) { + st->last_poll = jiffies; + if (!st->up) { u32 sec, min, hrs, days; sec = ntohl(cisco_data->time) / 1000; min = sec / 60; sec -= min * 60; @@ -232,12 +235,12 @@ static int cisco_rx(struct sk_buff *skb) days = hrs / 24; hrs -= days * 24; printk(KERN_INFO "%s: Link up (peer " "uptime %ud%uh%um%us)\n", - dev->name, days, hrs, - min, sec); + dev->name, days, hrs, min, sec); netif_dormant_off(dev); - state(hdlc)->up = 1; + st->up = 1; } } + spin_unlock(&st->lock); dev_kfree_skb_any(skb); return NET_RX_SUCCESS; @@ -261,24 +264,25 @@ static void cisco_timer(unsigned long arg) { struct net_device *dev = (struct net_device *)arg; hdlc_device *hdlc = dev_to_hdlc(dev); + struct cisco_state *st = state(hdlc); - if (state(hdlc)->up && - time_after(jiffies, state(hdlc)->last_poll + - state(hdlc)->settings.timeout * HZ)) { - state(hdlc)->up = 0; + spin_lock(&st->lock); + if (st->up && + time_after(jiffies, st->last_poll + st->settings.timeout * HZ)) { + st->up = 0; printk(KERN_INFO "%s: Link down\n", dev->name); netif_dormant_on(dev); } - cisco_keepalive_send(dev, CISCO_KEEPALIVE_REQ, - htonl(++state(hdlc)->txseq), - htonl(state(hdlc)->rxseq)); - state(hdlc)->request_sent = 1; - state(hdlc)->timer.expires = jiffies + - state(hdlc)->settings.interval * HZ; - state(hdlc)->timer.function = cisco_timer; - state(hdlc)->timer.data = arg; - add_timer(&state(hdlc)->timer); + cisco_keepalive_send(dev, CISCO_KEEPALIVE_REQ, htonl(++st->txseq), + htonl(st->rxseq)); + st->request_sent = 1; + spin_unlock(&st->lock); + + st->timer.expires = jiffies + st->settings.interval * HZ; + st->timer.function = cisco_timer; + st->timer.data = arg; + add_timer(&st->timer); } @@ -286,15 +290,20 @@ static void cisco_timer(unsigned long arg) static void cisco_start(struct net_device *dev) { hdlc_device *hdlc = dev_to_hdlc(dev); - state(hdlc)->up = 0; - state(hdlc)->request_sent = 0; - state(hdlc)->txseq = state(hdlc)->rxseq = 0; - - init_timer(&state(hdlc)->timer); - state(hdlc)->timer.expires = jiffies + HZ; /*First poll after 1s*/ - state(hdlc)->timer.function = cisco_timer; - state(hdlc)->timer.data = (unsigned long)dev; - add_timer(&state(hdlc)->timer); + struct cisco_state *st = state(hdlc); + unsigned long flags; + + spin_lock_irqsave(&st->lock, flags); + st->up = 0; + st->request_sent = 0; + st->txseq = st->rxseq = 0; + spin_unlock_irqrestore(&st->lock, flags); + + init_timer(&st->timer); + st->timer.expires = jiffies + HZ; /* First poll after 1 s */ + st->timer.function = cisco_timer; + st->timer.data = (unsigned long)dev; + add_timer(&st->timer); } @@ -302,10 +311,16 @@ static void cisco_start(struct net_device *dev) static void cisco_stop(struct net_device *dev) { hdlc_device *hdlc = dev_to_hdlc(dev); - del_timer_sync(&state(hdlc)->timer); + struct cisco_state *st = state(hdlc); + unsigned long flags; + + del_timer_sync(&st->timer); + + spin_lock_irqsave(&st->lock, flags); netif_dormant_on(dev); - state(hdlc)->up = 0; - state(hdlc)->request_sent = 0; + st->up = 0; + st->request_sent = 0; + spin_unlock_irqrestore(&st->lock, flags); } @@ -367,6 +382,7 @@ static int cisco_ioctl(struct net_device *dev, struct ifreq *ifr) return result; memcpy(&state(hdlc)->settings, &new_settings, size); + spin_lock_init(&state(hdlc)->lock); dev->hard_start_xmit = hdlc->xmit; dev->header_ops = &cisco_header_ops; dev->type = ARPHRD_CISCO; -- 2.20.1