diff options
| author | Willem de Bruijn <willemb@google.com> | 2014-11-19 13:10:16 -0500 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2014-11-21 14:43:07 -0500 |
| commit | 9c7077622dd917457ced680a23b7f175769471d9 (patch) | |
| tree | 8c162e5ef188298d9fce81c7d2a6fb216f2d0a5c /net/packet | |
| parent | df6ce47091620d76bbe036d0af3dc1abad4576c1 (diff) | |
| download | blackbird-op-linux-9c7077622dd917457ced680a23b7f175769471d9.tar.gz blackbird-op-linux-9c7077622dd917457ced680a23b7f175769471d9.zip | |
packet: make packet_snd fail on len smaller than l2 header
When sending packets out with PF_PACKET, SOCK_RAW, ensure that the
packet is at least as long as the device's expected link layer header.
This check already exists in tpacket_snd, but not in packet_snd.
Also rate limit the warning in tpacket_snd.
Signed-off-by: Willem de Bruijn <willemb@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/packet')
| -rw-r--r-- | net/packet/af_packet.c | 29 |
1 files changed, 21 insertions, 8 deletions
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index 4cd13d8de44b..58af58026dd2 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -2095,6 +2095,18 @@ static void tpacket_destruct_skb(struct sk_buff *skb) sock_wfree(skb); } +static bool ll_header_truncated(const struct net_device *dev, int len) +{ + /* net device doesn't like empty head */ + if (unlikely(len <= dev->hard_header_len)) { + net_warn_ratelimited("%s: packet size is too short (%d < %d)\n", + current->comm, len, dev->hard_header_len); + return true; + } + + return false; +} + static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb, void *frame, struct net_device *dev, int size_max, __be16 proto, unsigned char *addr, int hlen) @@ -2170,12 +2182,8 @@ static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb, if (unlikely(err < 0)) return -EINVAL; } else if (dev->hard_header_len) { - /* net device doesn't like empty head */ - if (unlikely(tp_len <= dev->hard_header_len)) { - pr_err("packet size is too short (%d < %d)\n", - tp_len, dev->hard_header_len); + if (ll_header_truncated(dev, tp_len)) return -EINVAL; - } skb_push(skb, dev->hard_header_len); err = skb_store_bits(skb, 0, data, @@ -2500,9 +2508,14 @@ static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len) skb_set_network_header(skb, reserve); err = -EINVAL; - if (sock->type == SOCK_DGRAM && - (offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len)) < 0) - goto out_free; + if (sock->type == SOCK_DGRAM) { + offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len); + if (unlikely(offset) < 0) + goto out_free; + } else { + if (ll_header_truncated(dev, len)) + goto out_free; + } /* Returns -EFAULT on error */ err = skb_copy_datagram_from_iovec(skb, offset, msg->msg_iov, 0, len); |
