On 5/27/20 7:44 AM, Jesper Dangaard Brouer wrote:
> The helper function xdp_set_data_meta_invalid() must be called after
> setting xdp->data as it depends on it.
>
> The bug was introduced in 39d6443c8daf ("mlx5, xsk: Migrate to
> new MEM_TYPE_XSK_BUFF_POOL"), and cause the kernel to crash when
> using BPF helper bpf_xdp_adjust_head() on mlx5 driver.
>
> Fixes: 39d6443c8daf ("mlx5, xsk: Migrate to new MEM_TYPE_XSK_BUFF_POOL")
> Reported-by: David Ahern <dsah...@kernel.org>
> Signed-off-by: Jesper Dangaard Brouer <bro...@redhat.com>
> ---
> drivers/net/ethernet/mellanox/mlx5/core/en_rx.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
> b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
> index 6b3c82da199c..dbb1c6323967 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
> @@ -1056,8 +1056,8 @@ static void mlx5e_fill_xdp_buff(struct mlx5e_rq *rq,
> void *va, u16 headroom,
> u32 len, struct xdp_buff *xdp)
> {
> xdp->data_hard_start = va;
> - xdp_set_data_meta_invalid(xdp);
> xdp->data = va + headroom;
> + xdp_set_data_meta_invalid(xdp);
> xdp->data_end = xdp->data + len;
> xdp->rxq = &rq->xdp_rxq;
> xdp->frame_sz = rq->buff.frame0_sz;
>
>
good catch. I looked right past that yesterday.
Tested-by: David Ahern <dsah...@gmail.com>
