| --- a/drivers/net/ppp/pptp.c |
| +++ b/drivers/net/ppp/pptp.c |
| @@ -308,6 +308,15 @@ static int pptp_rcv_core(struct sock *sk |
| (PPP_PROTOCOL(payload) == PPP_LCP) && |
| ((payload[4] == PPP_LCP_ECHOREQ) || (payload[4] == PPP_LCP_ECHOREP))) |
| goto allow_packet; |
| + |
| + /* |
| + * Updating seq_recv and checking seq of data packets causes |
| + * severe packet drop in multi-core scenario. It is bypassed |
| + * here as a workaround solution. |
| + */ |
| + if ((payload[0] == PPP_ALLSTATIONS) && (payload[1] == PPP_UI) && |
| + !PPP_PROTOCOL_CTRL(payload)) |
| + goto allow_packet; |
| } else { |
| opt->seq_recv = seq; |
| allow_packet: |
| --- a/include/uapi/linux/ppp_defs.h |
| +++ b/include/uapi/linux/ppp_defs.h |
| @@ -23,6 +23,7 @@ |
| #define PPP_ADDRESS(p) (((__u8 *)(p))[0]) |
| #define PPP_CONTROL(p) (((__u8 *)(p))[1]) |
| #define PPP_PROTOCOL(p) ((((__u8 *)(p))[2] << 8) + ((__u8 *)(p))[3]) |
| +#define PPP_PROTOCOL_CTRL(p) (PPP_PROTOCOL(p) & 0xF000) |
| |
| /* |
| * Significant octet values. |