Hi,
> -----Original Message-----
> From: Ferruh Yigit <ferruh.yi...@intel.com>
> Sent: Tuesday, September 8, 2020 1:07 PM
> To: dev@dpdk.org; Stephen Hemminger <sthem...@microsoft.com>; NBU-
> Contact-kys <k...@microsoft.com>; NBU-Contact-haiyangz
> <haiya...@microsoft.com>; NBU-Contact-longli <lon...@microsoft.com>
> Cc: Ferruh Yigit <ferruh.yi...@intel.com>; Raslan Darawsheh
> <rasl...@mellanox.com>
> Subject: [PATCH] net/netvsc: replace compiler builtin overflow check
>
> '__builtin_add_overflow' added to gcc in version 5, earlier versions
> causing build error, like gcc 4.8.5 in RHEL7.
>
> Replaced compiler builtin check with arithmetic check.
>
> Fixes: cabb3c0f29f1 ("net/netvsc: check for overflow on packet info from
> host")
>
> Reported-by: Raslan Darawsheh <rasl...@mellanox.com>
> Signed-off-by: Ferruh Yigit <ferruh.yi...@intel.com>
Tested-by: Raslan Darawsheh <rasl...@nvidia.com>
> ---
> drivers/net/netvsc/hn_rxtx.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/net/netvsc/hn_rxtx.c b/drivers/net/netvsc/hn_rxtx.c
> index d8d3f07f56..3e8d3b407d 100644
> --- a/drivers/net/netvsc/hn_rxtx.c
> +++ b/drivers/net/netvsc/hn_rxtx.c
> @@ -666,7 +666,7 @@ static void hn_rndis_rx_data(struct hn_rx_queue
> *rxq,
> struct hn_rx_bufinfo *rxb,
> void *data, uint32_t dlen)
> {
> - unsigned int data_off, data_len, total_len;
> + unsigned int data_off, data_len;
> unsigned int pktinfo_off, pktinfo_len;
> const struct rndis_packet_msg *pkt = data;
> struct hn_rxinfo info = {
> @@ -712,8 +712,8 @@ static void hn_rndis_rx_data(struct hn_rx_queue
> *rxq,
> goto error;
> }
>
> - if (__builtin_add_overflow(data_off, data_len, &total_len) ||
> - total_len > pkt->len)
> + /* overflow check */
> + if (data_len > data_len + data_off || data_len + data_off > pkt->len)
> goto error;
>
> if (unlikely(data_len < RTE_ETHER_HDR_LEN))
> --
> 2.25.4
Kindest regards
Raslan Darawsheh
