diff options
Diffstat (limited to 'net/atm/clip.c')
| -rw-r--r-- | net/atm/clip.c | 75 |
1 files changed, 53 insertions, 22 deletions
diff --git a/net/atm/clip.c b/net/atm/clip.c index 61b5b700817d..f7a5565e794e 100644 --- a/net/atm/clip.c +++ b/net/atm/clip.c @@ -45,7 +45,8 @@ #include <net/atmclip.h> static struct net_device *clip_devs; -static struct atm_vcc *atmarpd; +static struct atm_vcc __rcu *atmarpd; +static DEFINE_MUTEX(atmarpd_lock); static struct timer_list idle_timer; static const struct neigh_ops clip_neigh_ops; @@ -53,24 +54,35 @@ static int to_atmarpd(enum atmarp_ctrl_type type, int itf, __be32 ip) { struct sock *sk; struct atmarp_ctrl *ctrl; + struct atm_vcc *vcc; struct sk_buff *skb; + int err = 0; pr_debug("(%d)\n", type); - if (!atmarpd) - return -EUNATCH; + + rcu_read_lock(); + vcc = rcu_dereference(atmarpd); + if (!vcc) { + err = -EUNATCH; + goto unlock; + } skb = alloc_skb(sizeof(struct atmarp_ctrl), GFP_ATOMIC); - if (!skb) - return -ENOMEM; + if (!skb) { + err = -ENOMEM; + goto unlock; + } ctrl = skb_put(skb, sizeof(struct atmarp_ctrl)); ctrl->type = type; ctrl->itf_num = itf; ctrl->ip = ip; - atm_force_charge(atmarpd, skb->truesize); + atm_force_charge(vcc, skb->truesize); - sk = sk_atm(atmarpd); + sk = sk_atm(vcc); skb_queue_tail(&sk->sk_receive_queue, skb); sk->sk_data_ready(sk); - return 0; +unlock: + rcu_read_unlock(); + return err; } static void link_vcc(struct clip_vcc *clip_vcc, struct atmarp_entry *entry) @@ -193,12 +205,6 @@ static void clip_push(struct atm_vcc *vcc, struct sk_buff *skb) pr_debug("\n"); - if (!clip_devs) { - atm_return(vcc, skb->truesize); - kfree_skb(skb); - return; - } - if (!skb) { pr_debug("removing VCC %p\n", clip_vcc); if (clip_vcc->entry) @@ -208,6 +214,11 @@ static void clip_push(struct atm_vcc *vcc, struct sk_buff *skb) return; } atm_return(vcc, skb->truesize); + if (!clip_devs) { + kfree_skb(skb); + return; + } + skb->dev = clip_vcc->entry ? clip_vcc->entry->neigh->dev : clip_devs; /* clip_vcc->entry == NULL if we don't have an IP address yet */ if (!skb->dev) { @@ -418,6 +429,8 @@ static int clip_mkip(struct atm_vcc *vcc, int timeout) if (!vcc->push) return -EBADFD; + if (vcc->user_back) + return -EINVAL; clip_vcc = kmalloc(sizeof(struct clip_vcc), GFP_KERNEL); if (!clip_vcc) return -ENOMEM; @@ -608,17 +621,27 @@ static void atmarpd_close(struct atm_vcc *vcc) { pr_debug("\n"); - rtnl_lock(); - atmarpd = NULL; + mutex_lock(&atmarpd_lock); + RCU_INIT_POINTER(atmarpd, NULL); + mutex_unlock(&atmarpd_lock); + + synchronize_rcu(); skb_queue_purge(&sk_atm(vcc)->sk_receive_queue); - rtnl_unlock(); pr_debug("(done)\n"); module_put(THIS_MODULE); } +static int atmarpd_send(struct atm_vcc *vcc, struct sk_buff *skb) +{ + atm_return_tx(vcc, skb); + dev_kfree_skb_any(skb); + return 0; +} + static const struct atmdev_ops atmarpd_dev_ops = { - .close = atmarpd_close + .close = atmarpd_close, + .send = atmarpd_send }; @@ -632,15 +655,18 @@ static struct atm_dev atmarpd_dev = { static int atm_init_atmarp(struct atm_vcc *vcc) { - rtnl_lock(); + if (vcc->push == clip_push) + return -EINVAL; + + mutex_lock(&atmarpd_lock); if (atmarpd) { - rtnl_unlock(); + mutex_unlock(&atmarpd_lock); return -EADDRINUSE; } mod_timer(&idle_timer, jiffies + CLIP_CHECK_INTERVAL * HZ); - atmarpd = vcc; + rcu_assign_pointer(atmarpd, vcc); set_bit(ATM_VF_META, &vcc->flags); set_bit(ATM_VF_READY, &vcc->flags); /* allow replies and avoid getting closed if signaling dies */ @@ -649,13 +675,14 @@ static int atm_init_atmarp(struct atm_vcc *vcc) vcc->push = NULL; vcc->pop = NULL; /* crash */ vcc->push_oam = NULL; /* crash */ - rtnl_unlock(); + mutex_unlock(&atmarpd_lock); return 0; } static int clip_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) { struct atm_vcc *vcc = ATM_SD(sock); + struct sock *sk = sock->sk; int err = 0; switch (cmd) { @@ -676,14 +703,18 @@ static int clip_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) err = clip_create(arg); break; case ATMARPD_CTRL: + lock_sock(sk); err = atm_init_atmarp(vcc); if (!err) { sock->state = SS_CONNECTED; __module_get(THIS_MODULE); } + release_sock(sk); break; case ATMARP_MKIP: + lock_sock(sk); err = clip_mkip(vcc, arg); + release_sock(sk); break; case ATMARP_SETENTRY: err = clip_setentry(vcc, (__force __be32)arg); |