diff options
Diffstat (limited to 'drivers/net/ppp/ppp_generic.c')
| -rw-r--r-- | drivers/net/ppp/ppp_generic.c | 19 |
1 files changed, 17 insertions, 2 deletions
diff --git a/drivers/net/ppp/ppp_generic.c b/drivers/net/ppp/ppp_generic.c index fe380fe196e7..4b2971e2bf48 100644 --- a/drivers/net/ppp/ppp_generic.c +++ b/drivers/net/ppp/ppp_generic.c @@ -70,6 +70,7 @@ #define MPHDRLEN_SSN 4 /* ditto with short sequence numbers */ #define PPP_PROTO_LEN 2 +#define PPP_LCP_HDRLEN 4 /* * An instance of /dev/ppp can be associated with either a ppp @@ -493,6 +494,15 @@ static ssize_t ppp_read(struct file *file, char __user *buf, return ret; } +static bool ppp_check_packet(struct sk_buff *skb, size_t count) +{ + /* LCP packets must include LCP header which 4 bytes long: + * 1-byte code, 1-byte identifier, and 2-byte length. + */ + return get_unaligned_be16(skb->data) != PPP_LCP || + count >= PPP_PROTO_LEN + PPP_LCP_HDRLEN; +} + static ssize_t ppp_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos) { @@ -515,6 +525,11 @@ static ssize_t ppp_write(struct file *file, const char __user *buf, kfree_skb(skb); goto out; } + ret = -EINVAL; + if (unlikely(!ppp_check_packet(skb, count))) { + kfree_skb(skb); + goto out; + } switch (pf->kind) { case INTERFACE: @@ -1357,7 +1372,7 @@ static struct net *ppp_nl_get_link_net(const struct net_device *dev) { struct ppp *ppp = netdev_priv(dev); - return ppp->ppp_net; + return READ_ONCE(ppp->ppp_net); } static struct rtnl_link_ops ppp_link_ops __read_mostly = { @@ -1616,7 +1631,7 @@ static void ppp_setup(struct net_device *dev) dev->netdev_ops = &ppp_netdev_ops; SET_NETDEV_DEVTYPE(dev, &ppp_type); - dev->features |= NETIF_F_LLTX; + dev->lltx = true; dev->hard_header_len = PPP_HDRLEN; dev->mtu = PPP_MRU; |