diff options
Diffstat (limited to 'drivers/net/tun.c')
| -rw-r--r-- | drivers/net/tun.c | 21 |
1 files changed, 16 insertions, 5 deletions
diff --git a/drivers/net/tun.c b/drivers/net/tun.c index d27c3229465a..172273ae6575 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -1105,11 +1105,16 @@ static netdev_features_t tun_net_fix_features(struct net_device *dev, static void tun_set_headroom(struct net_device *dev, int new_hr) { struct tun_struct *tun = netdev_priv(dev); + size_t max_headroom; - if (new_hr < NET_SKB_PAD) - new_hr = NET_SKB_PAD; + max_headroom = min_t(size_t, SKB_MAX_HEAD(0), U16_MAX - 1); - tun->align = new_hr; + if ((tun->flags & TUN_TYPE_MASK) == IFF_TAP) + max_headroom -= ETH_HLEN + NET_IP_ALIGN; + else + max_headroom -= 1; + + tun->align = clamp_t(int, new_hr, NET_SKB_PAD, max_headroom); } static void @@ -1820,7 +1825,13 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, switch (tun->flags & TUN_TYPE_MASK) { case IFF_TUN: if (tun->flags & IFF_NO_PI) { - u8 ip_version = skb->len ? (skb->data[0] >> 4) : 0; + u8 ip_version; + + if (!pskb_may_pull(skb, 1)) { + err = -EINVAL; + goto drop; + } + ip_version = skb->data[0] >> 4; switch (ip_version) { case 4: @@ -1840,7 +1851,7 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, skb->dev = tun->dev; break; case IFF_TAP: - if (frags && !pskb_may_pull(skb, ETH_HLEN)) { + if (!pskb_may_pull(skb, ETH_HLEN)) { err = -ENOMEM; drop_reason = SKB_DROP_REASON_HDR_TRUNC; goto drop; |