From:   Florian Fainelli <f.fainelli@gmail.com>
To:     netdev@vger.kernel.org
Cc:     maxime@cerno.tech, Florian Fainelli <f.fainelli@gmail.com>,
        Doug Berger <opendmb@gmail.com>,
        Broadcom internal kernel review list 
        <bcm-kernel-feedback-list@broadcom.com>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        linux-kernel@vger.kernel.org (open list)
Subject: [PATCH net-next] net: bcmgenet: Add a check for oversized packets
Date:   Thu, 26 Jan 2023 16:08:19 -0800
Message-Id: <20230127000819.3934-1-f.fainelli@gmail.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

Occasionnaly we may get oversized packets from the hardware which
exceed the nomimal 2KiB buffer size we allocate SKBs with. Add an early
check which drops the packet to avoid invoking skb_over_panic() and move
on to processing the next packet.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
---
 drivers/net/ethernet/broadcom/genet/bcmgenet.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/net/ethernet/broadcom/genet/bcmgenet.c b/drivers/net/ethernet/broadcom/genet/bcmgenet.c
index 21973046b12b..d937daa8ee88 100644
--- a/drivers/net/ethernet/broadcom/genet/bcmgenet.c
+++ b/drivers/net/ethernet/broadcom/genet/bcmgenet.c
@@ -2316,6 +2316,14 @@ static unsigned int bcmgenet_desc_rx(struct bcmgenet_rx_ring *ring,
 			  __func__, p_index, ring->c_index,
 			  ring->read_ptr, dma_length_status);
 
+		if (unlikely(len > RX_BUF_LENGTH)) {
+			netif_err(priv, rx_status, dev, "oversized packet\n");
+			dev->stats.rx_length_errors++;
+			dev->stats.rx_errors++;
+			dev_kfree_skb_any(skb);
+			goto next;
+		}
+
 		if (unlikely(!(dma_flag & DMA_EOP) || !(dma_flag & DMA_SOP))) {
 			netif_err(priv, rx_status, dev,
 				  "dropping fragmented packet!\n");
-- 
2.25.1