net: wan: fsl_qmc_hdlc: Discard received CRC

commit e549360069b4a57e111b8222fc072f3c7c1688ab upstream.

Received frame from QMC contains the CRC.
Upper layers don't need this CRC and tcpdump mentioned trailing junk
data due to this CRC presence.

As some other HDLC driver, simply discard this CRC.

Fixes: d0f2258e79fd ("net: wan: Add support for QMC HDLC")
Cc: stable@vger.kernel.org
Signed-off-by: Herve Codina <herve.codina@bootlin.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20240730063133.179598-1-herve.codina@bootlin.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Herve Codina 2024-07-30 08:31:33 +02:00 committed by Greg Kroah-Hartman
parent f223d2b4ac
commit 2c9d235def

View File

@ -250,6 +250,7 @@ static void qmc_hcld_recv_complete(void *context, size_t length, unsigned int fl
struct qmc_hdlc_desc *desc = context;
struct net_device *netdev;
struct qmc_hdlc *qmc_hdlc;
size_t crc_size;
int ret;
netdev = desc->netdev;
@ -268,15 +269,26 @@ static void qmc_hcld_recv_complete(void *context, size_t length, unsigned int fl
if (flags & QMC_RX_FLAG_HDLC_CRC) /* CRC error */
netdev->stats.rx_crc_errors++;
kfree_skb(desc->skb);
} else {
netdev->stats.rx_packets++;
netdev->stats.rx_bytes += length;
skb_put(desc->skb, length);
desc->skb->protocol = hdlc_type_trans(desc->skb, netdev);
netif_rx(desc->skb);
goto re_queue;
}
/* Discard the CRC */
crc_size = qmc_hdlc->is_crc32 ? 4 : 2;
if (length < crc_size) {
netdev->stats.rx_length_errors++;
kfree_skb(desc->skb);
goto re_queue;
}
length -= crc_size;
netdev->stats.rx_packets++;
netdev->stats.rx_bytes += length;
skb_put(desc->skb, length);
desc->skb->protocol = hdlc_type_trans(desc->skb, netdev);
netif_rx(desc->skb);
re_queue:
/* Re-queue a transfer using the same descriptor */
ret = qmc_hdlc_recv_queue(qmc_hdlc, desc, desc->dma_size);
if (ret) {