On Mon, Jan 11, 2021 at 08:17:48PM +0200, Eran Ben Elisha wrote:
> Add support for parsing PTP L2 packet header. Such packet consists
> of an L2 header (with ethertype of ETH_P_1588), PTP header, body
> and an optional suffix.
>
> Signed-off-by: Eran Ben Elisha <era...@nvidia.com>
> Reviewed-by: Tariq Toukan <tar...@nvidia.com>
> ---
> net/core/flow_dissector.c | 16 ++++++++++++++++
> 1 file changed, 16 insertions(+)
>
> diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c
> index 6f1adba6695f..fcaa223c7cdc 100644
> --- a/net/core/flow_dissector.c
> +++ b/net/core/flow_dissector.c
> @@ -23,6 +23,7 @@
> #include <linux/if_ether.h>
> #include <linux/mpls.h>
> #include <linux/tcp.h>
> +#include <linux/ptp_classify.h>
> #include <net/flow_dissector.h>
> #include <scsi/fc/fc_fcoe.h>
> #include <uapi/linux/batadv_packet.h>
> @@ -1251,6 +1252,21 @@ bool __skb_flow_dissect(const struct net *net,
> &proto, &nhoff, hlen, flags);
> break;
>
> + case htons(ETH_P_1588): {
> + struct ptp_header *hdr, _hdr;
> +
> + hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data,
> + hlen, &_hdr);
> + if (!hdr || (hlen - nhoff) < sizeof(_hdr)) {
I'm not really familiar with the flow dissector, but why check (hlen - nhoff)
here?
None of the other cases do that. Doesn't skb_copy_bits() in
__skb_header_pointer() already handle that?
Thanks,
Richard
> + fdret = FLOW_DISSECT_RET_OUT_BAD;
> + break;
> + }
> +
> + nhoff += ntohs(hdr->message_length);
> + fdret = FLOW_DISSECT_RET_OUT_GOOD;
> + break;
> + }
> +
> default:
> fdret = FLOW_DISSECT_RET_OUT_BAD;
> break;
> --
> 2.17.1
>
