From: Foster Snowhill forst@pen.gy
[ Upstream commit 655b46d7a39ac6f049698b27c1568c0f7ff85d1e ]
Rx URB length was already checked in ipheth_rcvbulk_callback_legacy() and ipheth_rcvbulk_callback_ncm(), depending on the current mode. The check in ipheth_rcvbulk_callback() was thus mostly a duplicate.
The only place in ipheth_rcvbulk_callback() where we care about the URB length is for the initial control frame. These frames are always 4 bytes long. This has been checked as far back as iOS 4.2.1 on iPhone 3G.
Remove the extraneous URB length check. For control frames, check for the specific 4-byte length instead.
Signed-off-by: Foster Snowhill forst@pen.gy Tested-by: Georgi Valkov gvalkov@gmail.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/usb/ipheth.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-)
diff --git a/drivers/net/usb/ipheth.c b/drivers/net/usb/ipheth.c index 6eeef10edadad..017255615508f 100644 --- a/drivers/net/usb/ipheth.c +++ b/drivers/net/usb/ipheth.c @@ -286,11 +286,6 @@ static void ipheth_rcvbulk_callback(struct urb *urb) return; }
- if (urb->actual_length <= IPHETH_IP_ALIGN) { - dev->net->stats.rx_length_errors++; - return; - } - /* RX URBs starting with 0x00 0x01 do not encapsulate Ethernet frames, * but rather are control frames. Their purpose is not documented, and * they don't affect driver functionality, okay to drop them. @@ -298,7 +293,8 @@ static void ipheth_rcvbulk_callback(struct urb *urb) * URB received from the bulk IN endpoint. */ if (unlikely - (((char *)urb->transfer_buffer)[0] == 0 && + (urb->actual_length == 4 && + ((char *)urb->transfer_buffer)[0] == 0 && ((char *)urb->transfer_buffer)[1] == 1)) goto rx_submit;