From 2e36c9fbc476f95a1b19e3fa0a2cdf408475ff56 Mon Sep 17 00:00:00 2001 From: Paul Barker Date: Tue, 16 Apr 2024 13:02:54 +0100 Subject: [PATCH] net: ravb: Fix RX byte accounting for jumbo packets The RX byte accounting for jumbo packets was changed to fix a potential use-after-free bug. However, that fix used the wrong variable and so only accounted for the number of bytes in the final descriptor, not the number of bytes in the whole packet. To fix this, we can simply update our stats with the correct number of bytes before calling napi_gro_receive(). Also rename pkt_len to desc_len in ravb_rx_gbeth() to avoid any future confusion. The variable name pkt_len is correct in ravb_rx_rcar() as that function does not handle packets spanning multiple descriptors. Fixes: 5a5a3e564de6 ("ravb: Fix potential use-after-free in ravb_rx_gbeth()") Signed-off-by: Paul Barker Reviewed-by: Sergey Shtylyov Signed-off-by: Paolo Abeni --- drivers/net/ethernet/renesas/ravb_main.c | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-) diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c index 6969cdeeb67ab2..fcb756d77681cb 100644 --- a/drivers/net/ethernet/renesas/ravb_main.c +++ b/drivers/net/ethernet/renesas/ravb_main.c @@ -769,7 +769,7 @@ static bool ravb_rx_gbeth(struct net_device *ndev, int *quota, int q) dma_addr_t dma_addr; int rx_packets = 0; u8 desc_status; - u16 pkt_len; + u16 desc_len; u8 die_dt; int entry; int limit; @@ -787,10 +787,10 @@ static bool ravb_rx_gbeth(struct net_device *ndev, int *quota, int q) /* Descriptor type must be checked before all other reads */ dma_rmb(); desc_status = desc->msc; - pkt_len = le16_to_cpu(desc->ds_cc) & RX_DS; + desc_len = le16_to_cpu(desc->ds_cc) & RX_DS; /* We use 0-byte descriptors to mark the DMA mapping errors */ - if (!pkt_len) + if (!desc_len) continue; if (desc_status & MSC_MC) @@ -811,25 +811,25 @@ static bool ravb_rx_gbeth(struct net_device *ndev, int *quota, int q) switch (die_dt) { case DT_FSINGLE: skb = ravb_get_skb_gbeth(ndev, entry, desc); - skb_put(skb, pkt_len); + skb_put(skb, desc_len); skb->protocol = eth_type_trans(skb, ndev); if (ndev->features & NETIF_F_RXCSUM) ravb_rx_csum_gbeth(skb); napi_gro_receive(&priv->napi[q], skb); rx_packets++; - stats->rx_bytes += pkt_len; + stats->rx_bytes += desc_len; break; case DT_FSTART: priv->rx_1st_skb = ravb_get_skb_gbeth(ndev, entry, desc); - skb_put(priv->rx_1st_skb, pkt_len); + skb_put(priv->rx_1st_skb, desc_len); break; case DT_FMID: skb = ravb_get_skb_gbeth(ndev, entry, desc); skb_copy_to_linear_data_offset(priv->rx_1st_skb, priv->rx_1st_skb->len, skb->data, - pkt_len); - skb_put(priv->rx_1st_skb, pkt_len); + desc_len); + skb_put(priv->rx_1st_skb, desc_len); dev_kfree_skb(skb); break; case DT_FEND: @@ -837,17 +837,17 @@ static bool ravb_rx_gbeth(struct net_device *ndev, int *quota, int q) skb_copy_to_linear_data_offset(priv->rx_1st_skb, priv->rx_1st_skb->len, skb->data, - pkt_len); - skb_put(priv->rx_1st_skb, pkt_len); + desc_len); + skb_put(priv->rx_1st_skb, desc_len); dev_kfree_skb(skb); priv->rx_1st_skb->protocol = eth_type_trans(priv->rx_1st_skb, ndev); if (ndev->features & NETIF_F_RXCSUM) ravb_rx_csum_gbeth(priv->rx_1st_skb); + stats->rx_bytes += priv->rx_1st_skb->len; napi_gro_receive(&priv->napi[q], priv->rx_1st_skb); rx_packets++; - stats->rx_bytes += pkt_len; break; } }