diff options
Diffstat (limited to 'drivers/net/ppp/ppp_generic.c')
| -rw-r--r-- | drivers/net/ppp/ppp_generic.c | 17 |
1 files changed, 11 insertions, 6 deletions
diff --git a/drivers/net/ppp/ppp_generic.c b/drivers/net/ppp/ppp_generic.c index 8c98cbd4b06d..824c8dc4120b 100644 --- a/drivers/net/ppp/ppp_generic.c +++ b/drivers/net/ppp/ppp_generic.c @@ -33,6 +33,7 @@ #include <linux/ppp_channel.h> #include <linux/ppp-comp.h> #include <linux/skbuff.h> +#include <linux/rculist.h> #include <linux/rtnetlink.h> #include <linux/if_arp.h> #include <linux/ip.h> @@ -1598,11 +1599,14 @@ static int ppp_fill_forward_path(struct net_device_path_ctx *ctx, if (ppp->flags & SC_MULTILINK) return -EOPNOTSUPP; - if (list_empty(&ppp->channels)) + pch = list_first_or_null_rcu(&ppp->channels, struct channel, clist); + if (!pch) + return -ENODEV; + + chan = READ_ONCE(pch->chan); + if (!chan) return -ENODEV; - pch = list_first_entry(&ppp->channels, struct channel, clist); - chan = pch->chan; if (!chan->ops->fill_forward_path) return -EOPNOTSUPP; @@ -2994,7 +2998,7 @@ ppp_unregister_channel(struct ppp_channel *chan) */ down_write(&pch->chan_sem); spin_lock_bh(&pch->downl); - pch->chan = NULL; + WRITE_ONCE(pch->chan, NULL); spin_unlock_bh(&pch->downl); up_write(&pch->chan_sem); ppp_disconnect_channel(pch); @@ -3515,7 +3519,7 @@ ppp_connect_channel(struct channel *pch, int unit) hdrlen = pch->file.hdrlen + 2; /* for protocol bytes */ if (hdrlen > ppp->dev->hard_header_len) ppp->dev->hard_header_len = hdrlen; - list_add_tail(&pch->clist, &ppp->channels); + list_add_tail_rcu(&pch->clist, &ppp->channels); ++ppp->n_channels; pch->ppp = ppp; refcount_inc(&ppp->file.refcnt); @@ -3545,10 +3549,11 @@ ppp_disconnect_channel(struct channel *pch) if (ppp) { /* remove it from the ppp unit's list */ ppp_lock(ppp); - list_del(&pch->clist); + list_del_rcu(&pch->clist); if (--ppp->n_channels == 0) wake_up_interruptible(&ppp->file.rwait); ppp_unlock(ppp); + synchronize_net(); if (refcount_dec_and_test(&ppp->file.refcnt)) ppp_destroy_interface(ppp); err = 0; |