From c9af6db4c11ccc6c3e7f19bbc15d54023956f97c Mon Sep 17 00:00:00 2001 From: Pravin B Shelar Date: Mon, 11 Feb 2013 09:27:41 +0000 Subject: net: Fix possible wrong checksum generation. Patch cef401de7be8c4e (net: fix possible wrong checksum generation) fixed wrong checksum calculation but it broke TSO by defining new GSO type but not a netdev feature for that type. net_gso_ok() would not allow hardware checksum/segmentation offload of such packets without the feature. Following patch fixes TSO and wrong checksum. This patch uses same logic that Eric Dumazet used. Patch introduces new flag SKBTX_SHARED_FRAG if at least one frag can be modified by the user. but SKBTX_SHARED_FRAG flag is kept in skb shared info tx_flags rather than gso_type. tx_flags is better compared to gso_type since we can have skb with shared frag without gso packet. It does not link SHARED_FRAG to GSO, So there is no need to define netdev feature for this. Signed-off-by: Pravin B Shelar Signed-off-by: David S. Miller --- drivers/net/tun.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) (limited to 'drivers/net/tun.c') diff --git a/drivers/net/tun.c b/drivers/net/tun.c index b1038c0e2240..b6f45c5d84d5 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -1019,7 +1019,6 @@ static int zerocopy_sg_from_iovec(struct sk_buff *skb, const struct iovec *from, skb->data_len += len; skb->len += len; skb->truesize += truesize; - skb_shinfo(skb)->gso_type |= SKB_GSO_SHARED_FRAG; atomic_add(truesize, &skb->sk->sk_wmem_alloc); while (len) { int off = base & ~PAGE_MASK; @@ -1165,18 +1164,16 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, } if (gso.gso_type != VIRTIO_NET_HDR_GSO_NONE) { - unsigned short gso_type = 0; - pr_debug("GSO!\n"); switch (gso.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) { case VIRTIO_NET_HDR_GSO_TCPV4: - gso_type = SKB_GSO_TCPV4; + skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4; break; case VIRTIO_NET_HDR_GSO_TCPV6: - gso_type = SKB_GSO_TCPV6; + skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6; break; case VIRTIO_NET_HDR_GSO_UDP: - gso_type = SKB_GSO_UDP; + skb_shinfo(skb)->gso_type = SKB_GSO_UDP; break; default: tun->dev->stats.rx_frame_errors++; @@ -1185,10 +1182,9 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, } if (gso.gso_type & VIRTIO_NET_HDR_GSO_ECN) - gso_type |= SKB_GSO_TCP_ECN; + skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN; skb_shinfo(skb)->gso_size = gso.gso_size; - skb_shinfo(skb)->gso_type |= gso_type; if (skb_shinfo(skb)->gso_size == 0) { tun->dev->stats.rx_frame_errors++; kfree_skb(skb); @@ -1204,6 +1200,7 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, if (zerocopy) { skb_shinfo(skb)->destructor_arg = msg_control; skb_shinfo(skb)->tx_flags |= SKBTX_DEV_ZEROCOPY; + skb_shinfo(skb)->tx_flags |= SKBTX_SHARED_FRAG; } skb_reset_network_header(skb); -- cgit v1.2.1