From: Stephane Graber <stgraber@xxxxxxxxxx> commit e9e6faeafaa00da1851bcf47912b0f1acae666b4 upstream. All packets on ingress (except for jumbo) are terminated with a 4-bytes CRC checksum. It's the responsability of the driver to strip those 4 bytes. Unfortunately a change dating back to March 2017 re-shuffled some code and made the CRC stripping code effectively dead. This change re-orders that part a bit such that the datalen is immediately altered if needed. Fixes: 4902a92270fb ("drivers: net: xgene: Add workaround for errata 10GE_8/ENET_11") Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Stephane Graber <stgraber@xxxxxxxxxx> Tested-by: Stephane Graber <stgraber@xxxxxxxxxx> Link: https://lore.kernel.org/r/20220322224205.752795-1-stgraber@xxxxxxxxxx Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/ethernet/apm/xgene/xgene_enet_main.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) --- a/drivers/net/ethernet/apm/xgene/xgene_enet_main.c +++ b/drivers/net/ethernet/apm/xgene/xgene_enet_main.c @@ -707,6 +707,12 @@ static int xgene_enet_rx_frame(struct xg buf_pool->rx_skb[skb_index] = NULL; datalen = xgene_enet_get_data_len(le64_to_cpu(raw_desc->m1)); + + /* strip off CRC as HW isn't doing this */ + nv = GET_VAL(NV, le64_to_cpu(raw_desc->m0)); + if (!nv) + datalen -= 4; + skb_put(skb, datalen); prefetch(skb->data - NET_IP_ALIGN); skb->protocol = eth_type_trans(skb, ndev); @@ -728,12 +734,8 @@ static int xgene_enet_rx_frame(struct xg } } - nv = GET_VAL(NV, le64_to_cpu(raw_desc->m0)); - if (!nv) { - /* strip off CRC as HW isn't doing this */ - datalen -= 4; + if (!nv) goto skip_jumbo; - } slots = page_pool->slots - 1; head = page_pool->head; Patches currently in stable-queue which might be from stgraber@xxxxxxxxxx are queue-4.14/drivers-net-xgene-fix-regression-in-crc-stripping.patch