3.9-stable review patch. If anyone has any objections, please let me know.
------------------ From: Jason Wang <[email protected]> [ Upstream commit 38502af77e07b5d6650b9ff99a0b482d86366592 ] Currently, for the packets receives from tuntap, before doing header check, kernel just reset the transport header in netif_receive_skb() which pretends no l4 header. This is suboptimal for precise packet length estimation (introduced in 1def9238) which needs correct l4 header for gso packets. So this patch set the transport header to csum_start for partial checksum packets, otherwise it first try skb_flow_dissect(), if it fails, just reset the transport header. Signed-off-by: Jason Wang <[email protected]> Cc: Eric Dumazet <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/net/tun.c | 10 ++++++++++ 1 file changed, 10 insertions(+) --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -70,6 +70,7 @@ #include <net/sock.h> #include <asm/uaccess.h> +#include <net/flow_keys.h> /* Uncomment to enable debugging */ /* #define TUN_DEBUG 1 */ @@ -1051,6 +1052,7 @@ static ssize_t tun_get_user(struct tun_s bool zerocopy = false; int err; u32 rxhash; + struct flow_keys keys; if (!(tun->flags & TUN_NO_PI)) { if ((len -= sizeof(pi)) > total_len) @@ -1205,6 +1207,14 @@ static ssize_t tun_get_user(struct tun_s } skb_reset_network_header(skb); + + if (skb->ip_summed == CHECKSUM_PARTIAL) + skb_set_transport_header(skb, skb_checksum_start_offset(skb)); + else if (skb_flow_dissect(skb, &keys)) + skb_set_transport_header(skb, keys.thoff); + else + skb_reset_transport_header(skb); + rxhash = skb_get_rxhash(skb); netif_rx_ni(skb); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
