net: usb: lan78xx: limit size of local TSO packets

lan78xx_tx_bh() makes sure to not exceed MAX_SINGLE_PACKET_SIZE
bytes in the aggregated packets it builds, but does
nothing to prevent large GSO packets being submitted.

Pierre-Francois reported various hangs when/if TSO is enabled.

For localy generated packets, we can use netif_set_gso_max_size()
to limit the size of TSO packets.

Note that forwarded packets could still hit the issue,
so a complete fix might require implementing .ndo_features_check
for this driver, forcing a software segmentation if the size
of the TSO packet exceeds MAX_SINGLE_PACKET_SIZE.

Fixes: 55d7de9de6 ("Microchip's LAN7800 family USB 2/3 to 10/100/1000 Ethernet device driver")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: RENARD Pierre-Francois <pfrenard@gmail.com>
Tested-by: RENARD Pierre-Francois <pfrenard@gmail.com>
Cc: Stefan Wahren <stefan.wahren@i2se.com>
Cc: Woojung Huh <woojung.huh@microchip.com>
Cc: Microchip Linux Driver Support <UNGLinuxDriver@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2020-01-13 09:27:11 -08:00 committed by David S. Miller
parent 75718584cb
commit f8d7408a4d
1 changed files with 1 additions and 0 deletions

View File

@ -3750,6 +3750,7 @@ static int lan78xx_probe(struct usb_interface *intf,
/* MTU range: 68 - 9000 */
netdev->max_mtu = MAX_SINGLE_PACKET_SIZE;
netif_set_gso_max_size(netdev, MAX_SINGLE_PACKET_SIZE - MAX_HEADER);
dev->ep_blkin = (intf->cur_altsetting)->endpoint + 0;
dev->ep_blkout = (intf->cur_altsetting)->endpoint + 1;