From 09effa67a18d893fc4e6f81a3659fc9efef1445e Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Wed, 7 Aug 2013 17:11:00 -0700 Subject: [PATCH] packet: Revert recent header parsing changes. This reverts commits: 0f75b09c798ed00c30d7d5551b896be883bc2aeb cbd89acb9eb257ed3b2be867142583fdcf7fdc5b c483e02614551e44ced3fe6eedda8e36d3277ccc Amongst other things, it's modifies the SKB header to pull the ethernet headers off via eth_type_trans() on the output path which is bogus. It's causing serious regressions for people. Signed-off-by: David S. Miller --- net/packet/af_packet.c | 53 +++++++++++++++++++----------------------- 1 file changed, 24 insertions(+), 29 deletions(-) diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index 0c0f6c9a90e7..4cb28a7f639b 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -88,7 +88,6 @@ #include #include #include -#include #ifdef CONFIG_INET #include @@ -1924,7 +1923,7 @@ static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb, __be16 proto, unsigned char *addr, int hlen) { union tpacket_uhdr ph; - int to_write, offset, len, tp_len, nr_frags, len_max, max_frame_len; + int to_write, offset, len, tp_len, nr_frags, len_max; struct socket *sock = po->sk.sk_socket; struct page *page; void *data; @@ -1947,6 +1946,10 @@ static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb, tp_len = ph.h1->tp_len; break; } + if (unlikely(tp_len > size_max)) { + pr_err("packet size is too long (%d > %d)\n", tp_len, size_max); + return -EMSGSIZE; + } skb_reserve(skb, hlen); skb_reset_network_header(skb); @@ -2002,25 +2005,10 @@ static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb, if (unlikely(err)) return err; - if (dev->type == ARPHRD_ETHER) - skb->protocol = eth_type_trans(skb, dev); - data += dev->hard_header_len; to_write -= dev->hard_header_len; } - max_frame_len = dev->mtu + dev->hard_header_len; - if (skb->protocol == htons(ETH_P_8021Q)) - max_frame_len += VLAN_HLEN; - - if (size_max > max_frame_len) - size_max = max_frame_len; - - if (unlikely(tp_len > size_max)) { - pr_err("packet size is too long (%d > %d)\n", tp_len, size_max); - return -EMSGSIZE; - } - offset = offset_in_page(data); len_max = PAGE_SIZE - offset; len = ((to_write > len_max) ? len_max : to_write); @@ -2059,7 +2047,7 @@ static int tpacket_snd(struct packet_sock *po, struct msghdr *msg) struct net_device *dev; __be16 proto; bool need_rls_dev = false; - int err; + int err, reserve = 0; void *ph; struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name; int tp_len, size_max; @@ -2092,6 +2080,8 @@ static int tpacket_snd(struct packet_sock *po, struct msghdr *msg) if (unlikely(dev == NULL)) goto out; + reserve = dev->hard_header_len; + err = -ENETDOWN; if (unlikely(!(dev->flags & IFF_UP))) goto out_put; @@ -2099,6 +2089,9 @@ static int tpacket_snd(struct packet_sock *po, struct msghdr *msg) size_max = po->tx_ring.frame_size - (po->tp_hdrlen - sizeof(struct sockaddr_ll)); + if (size_max > dev->mtu + reserve) + size_max = dev->mtu + reserve; + do { ph = packet_current_frame(po, &po->tx_ring, TP_STATUS_SEND_REQUEST); @@ -2331,20 +2324,22 @@ static int packet_snd(struct socket *sock, sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags); - if (dev->type == ARPHRD_ETHER) { - skb->protocol = eth_type_trans(skb, dev); - if (skb->protocol == htons(ETH_P_8021Q)) - reserve += VLAN_HLEN; - } else { - skb->protocol = proto; - skb->dev = dev; - } - if (!gso_type && (len > dev->mtu + reserve + extra_len)) { - err = -EMSGSIZE; - goto out_free; + /* Earlier code assumed this would be a VLAN pkt, + * double-check this now that we have the actual + * packet in hand. + */ + struct ethhdr *ehdr; + skb_reset_mac_header(skb); + ehdr = eth_hdr(skb); + if (ehdr->h_proto != htons(ETH_P_8021Q)) { + err = -EMSGSIZE; + goto out_free; + } } + skb->protocol = proto; + skb->dev = dev; skb->priority = sk->sk_priority; skb->mark = sk->sk_mark; -- 2.20.1