4.9-stable review patch. If anyone has any objections, please let me know.
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From: Michael Chan michael.chan@broadcom.com
[ Upstream commit 2b3c6885386020b1b9d92d45e8349637e27d1f66 ]
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 Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/ethernet/broadcom/bnxt/bnxt.c | 6 ++++++ 1 file changed, 6 insertions(+)
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c @@ -428,6 +428,12 @@ normal_tx: }
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);