net/mlx5e: RX, verify received packet size in Linear Striding RQ

[ Upstream commit 0073c8f72736b423aade8a817587a5f3e4df4ad8 ]

In case of striding RQ, we use  MPWRQ (Multi Packet WQE RQ), which means
that WQE (RX descriptor) can be used for many packets and so the WQE is
much bigger than MTU.  In virtualization setups where the port mtu can
be larger than the vf mtu, if received packet is bigger than MTU, it
won't be dropped by HW on too small receive WQE. If we use linear SKB in
striding RQ, since each stride has room for mtu size payload and skb
info, an oversized packet can lead to crash for crossing allocated page
boundary upon the call to build_skb. So driver needs to check packet
size and drop it.

Introduce new SW rx counter, rx_oversize_pkts_sw_drop, which counts the
number of packets dropped by the driver for being too large.

As a new field is added to the RQ struct, re-open the channels whenever
this field is being used in datapath (i.e., in the case of linear
Striding RQ).

Fixes: 619a8f2a42f1 ("net/mlx5e: Use linear SKB in Striding RQ")
Signed-off-by: Moshe Shemesh <moshe@mellanox.com>
Reviewed-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en.h b/drivers/net/ethernet/mellanox/mlx5/core/en.h
index 0f189f87385923226966a57537b7fa643e540a98..16ceeb1b2c9d8555b76c5914574421edbd66c6da 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx5/core/en.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en.h
@@ -566,6 +566,7 @@ struct mlx5e_rq {
 
        unsigned long          state;
        int                    ix;
+       unsigned int           hw_mtu;
 
        struct net_dim         dim; /* Dynamic Interrupt Moderation */
 

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
index 6e8eead8fde585ca7527ace14ec34e7a7807e179..faa84b45e20abfdb3dcbe4dcaa8fbb24fb2de6eb 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
@@ -492,6 +492,7 @@ static int mlx5e_alloc_rq(struct mlx5e_channel *c,
        rq->channel = c;
        rq->ix      = c->ix;
        rq->mdev    = mdev;
+       rq->hw_mtu  = MLX5E_SW2HW_MTU(params, params->sw_mtu);
        rq->stats   = &c->priv->channel_stats[c->ix].rq;
 
        rq->xdp_prog = params->xdp_prog ? bpf_prog_inc(params->xdp_prog) : NULL;
@@ -3758,10 +3759,11 @@ int mlx5e_change_mtu(struct net_device *netdev, int new_mtu,
        }
 
        if (params->rq_wq_type == MLX5_WQ_TYPE_LINKED_LIST_STRIDING_RQ) {
+               bool is_linear = mlx5e_rx_mpwqe_is_linear_skb(priv->mdev, &new_channels.params);
                u8 ppw_old = mlx5e_mpwqe_log_pkts_per_wqe(params);
                u8 ppw_new = mlx5e_mpwqe_log_pkts_per_wqe(&new_channels.params);
 
-               reset = reset && (ppw_old != ppw_new);
+               reset = reset && (is_linear || (ppw_old != ppw_new));
        }
 
        if (!reset) {

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
index a144146b769c1d0b6a3ebbcbfdcb6d2685fd03c8..d543a5cff049c73402bfc09a46f8da7cdea63e3f 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
@@ -1064,6 +1064,12 @@ mlx5e_skb_from_cqe_mpwrq_linear(struct mlx5e_rq *rq, struct mlx5e_mpw_info *wi,
        u32 frag_size;
        bool consumed;
 
+       /* Check packet size. Note LRO doesn't use linear SKB */
+       if (unlikely(cqe_bcnt > rq->hw_mtu)) {
+               rq->stats->oversize_pkts_sw_drop++;
+               return NULL;
+       }
+
        va             = page_address(di->page) + head_offset;
        data           = va + rx_headroom;
        frag_size      = MLX5_SKB_FRAG_SZ(rx_headroom + cqe_bcnt32);

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_stats.c b/drivers/net/ethernet/mellanox/mlx5/core/en_stats.c
index 6839481f76974c7f39b2c99ccb8fce4ba89953ea..d57d51c4e65873bd67c2ec4d04a896f4c087becb 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_stats.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_stats.c
@@ -82,6 +82,7 @@ static const struct counter_desc sw_stats_desc[] = {
        { MLX5E_DECLARE_STAT(struct mlx5e_sw_stats, rx_wqe_err) },
        { MLX5E_DECLARE_STAT(struct mlx5e_sw_stats, rx_mpwqe_filler_cqes) },
        { MLX5E_DECLARE_STAT(struct mlx5e_sw_stats, rx_mpwqe_filler_strides) },
+       { MLX5E_DECLARE_STAT(struct mlx5e_sw_stats, rx_oversize_pkts_sw_drop) },
        { MLX5E_DECLARE_STAT(struct mlx5e_sw_stats, rx_buff_alloc_err) },
        { MLX5E_DECLARE_STAT(struct mlx5e_sw_stats, rx_cqe_compress_blks) },
        { MLX5E_DECLARE_STAT(struct mlx5e_sw_stats, rx_cqe_compress_pkts) },
@@ -158,6 +159,7 @@ void mlx5e_grp_sw_update_stats(struct mlx5e_priv *priv)
                s->rx_wqe_err   += rq_stats->wqe_err;
                s->rx_mpwqe_filler_cqes    += rq_stats->mpwqe_filler_cqes;
                s->rx_mpwqe_filler_strides += rq_stats->mpwqe_filler_strides;
+               s->rx_oversize_pkts_sw_drop += rq_stats->oversize_pkts_sw_drop;
                s->rx_buff_alloc_err += rq_stats->buff_alloc_err;
                s->rx_cqe_compress_blks += rq_stats->cqe_compress_blks;
                s->rx_cqe_compress_pkts += rq_stats->cqe_compress_pkts;
@@ -1148,6 +1150,7 @@ static const struct counter_desc rq_stats_desc[] = {
        { MLX5E_DECLARE_RX_STAT(struct mlx5e_rq_stats, wqe_err) },
        { MLX5E_DECLARE_RX_STAT(struct mlx5e_rq_stats, mpwqe_filler_cqes) },
        { MLX5E_DECLARE_RX_STAT(struct mlx5e_rq_stats, mpwqe_filler_strides) },
+       { MLX5E_DECLARE_RX_STAT(struct mlx5e_rq_stats, oversize_pkts_sw_drop) },
        { MLX5E_DECLARE_RX_STAT(struct mlx5e_rq_stats, buff_alloc_err) },
        { MLX5E_DECLARE_RX_STAT(struct mlx5e_rq_stats, cqe_compress_blks) },
        { MLX5E_DECLARE_RX_STAT(struct mlx5e_rq_stats, cqe_compress_pkts) },

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_stats.h b/drivers/net/ethernet/mellanox/mlx5/core/en_stats.h
index a4c035aedd46cfe2c64e24f02f64bf90bf809e46..c1064af9d54c6dc32ea921721b04877a54587b8e 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_stats.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_stats.h
@@ -95,6 +95,7 @@ struct mlx5e_sw_stats {
        u64 rx_wqe_err;
        u64 rx_mpwqe_filler_cqes;
        u64 rx_mpwqe_filler_strides;
+       u64 rx_oversize_pkts_sw_drop;
        u64 rx_buff_alloc_err;
        u64 rx_cqe_compress_blks;
        u64 rx_cqe_compress_pkts;
@@ -190,6 +191,7 @@ struct mlx5e_rq_stats {
        u64 wqe_err;
        u64 mpwqe_filler_cqes;
        u64 mpwqe_filler_strides;
+       u64 oversize_pkts_sw_drop;
        u64 buff_alloc_err;
        u64 cqe_compress_blks;
        u64 cqe_compress_pkts;