From 2b3c6885386020b1b9d92d45e8349637e27d1f66 Mon Sep 17 00:00:00 2001
From: Michael Chan <michael.chan@broadcom.com>
Date: Wed, 27 Feb 2019 03:58:53 -0500
Subject: [PATCH] bnxt_en: Drop oversize TX packets to prevent errors.
There have been reports of oversize UDP packets being sent to the
driver to be transmitted, causing error conditions. The issue is
likely caused by the dst of the SKB switching between 'lo' with
64K MTU and the hardware device with a smaller MTU. Patches are
being proposed by Mahesh Bandewar <maheshb@google.com> to fix the
issue.
In the meantime, add a quick length check in the driver to prevent
the error. The driver uses the TX packet size as index to look up an
array to setup the TX BD. The array is large enough to support all MTU
sizes supported by the driver. The oversize TX packet causes the
driver to index beyond the array and put garbage values into the
TX BD. Add a simple check to prevent this.
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
drivers/net/ethernet/broadcom/bnxt/bnxt.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index d95730c6e0f20..803f7990d32b3 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -500,6 +500,12 @@ static netdev_tx_t bnxt_start_xmit(struct sk_buff *skb, struct net_device *dev)
}
length >>= 9;
+ if (unlikely(length >= ARRAY_SIZE(bnxt_lhint_arr))) {
+ dev_warn_ratelimited(&pdev->dev, "Dropped oversize %d bytes TX packet.\n",
+ skb->len);
+ i = 0;
+ goto tx_dma_error;
+ }
flags |= bnxt_lhint_arr[length];
txbd->tx_bd_len_flags_type = cpu_to_le32(flags);
--
GitLab