From: Joshua Hay joshua.a.hay@intel.com

When a mailbox message is received, the driver is checking for a non 0 datalen in the controlq descriptor. If it is valid, the payload is attached to the ctlq message to give to the upper layer. However, the payload response size given to the upper layer was taken from the buffer metadata which is _always_ the max buffer size. This meant the API was returning 4K as the payload size for all messages. This went unnoticed since the virtchnl exchange response logic was checking for a response size less than 0 (error), not less than exact size, or not greater than or equal to the max mailbox buffer size (4K). All of these checks will pass in the success case since the size provided is always 4K. However, this breaks anyone that wants to validate the exact response size.

Fetch the actual payload length from the value provided in the descriptor data_len field (instead of the buffer metadata).

Unfortunately, this means we lose some extra error parsing for variable sized virtchnl responses such as create vport and get ptypes. However, the original checks weren't really helping anyways since the size was _always_ 4K.

Fixes: 34c21fa894a1 ("idpf: implement virtchnl transaction manager") Cc: stable@vger.kernel.org # 6.9+ Signed-off-by: Joshua Hay joshua.a.hay@intel.com Reviewed-by: Przemek Kitszel przemyslaw.kitszel@intel.com Tested-by: Krishneil Singh krishneil.k.singh@intel.com Signed-off-by: Tony Nguyen anthony.l.nguyen@intel.com --- drivers/net/ethernet/intel/idpf/idpf_virtchnl.c | 9 +-------- 1 file changed, 1 insertion(+), 8 deletions(-)

diff --git a/drivers/net/ethernet/intel/idpf/idpf_virtchnl.c b/drivers/net/ethernet/intel/idpf/idpf_virtchnl.c index 70986e12da28..3c0f97650d72 100644 --- a/drivers/net/ethernet/intel/idpf/idpf_virtchnl.c +++ b/drivers/net/ethernet/intel/idpf/idpf_virtchnl.c @@ -666,7 +666,7 @@ idpf_vc_xn_forward_reply(struct idpf_adapter *adapter,

if (ctlq_msg->data_len) { payload = ctlq_msg->ctx.indirect.payload->va; - payload_size = ctlq_msg->ctx.indirect.payload->size; + payload_size = ctlq_msg->data_len; }

xn->reply_sz = payload_size; @@ -1295,10 +1295,6 @@ int idpf_send_create_vport_msg(struct idpf_adapter *adapter, err = reply_sz; goto free_vport_params; } - if (reply_sz < IDPF_CTLQ_MAX_BUF_LEN) { - err = -EIO; - goto free_vport_params; - }

return 0;

@@ -2602,9 +2598,6 @@ int idpf_send_get_rx_ptype_msg(struct idpf_vport *vport) if (reply_sz < 0) return reply_sz;

- if (reply_sz < IDPF_CTLQ_MAX_BUF_LEN) - return -EIO; - ptypes_recvd += le16_to_cpu(ptype_info->num_ptypes); if (ptypes_recvd > max_ptype) return -EINVAL;