From f8d7408a4d7f60f8b2df0f81decdc882dd9c20dc Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Mon, 13 Jan 2020 09:27:11 -0800 Subject: [PATCH] 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: 55d7de9de6c3 ("Microchip's LAN7800 family USB 2/3 to 10/100/1000 Ethernet device driver") Signed-off-by: Eric Dumazet Reported-by: RENARD Pierre-Francois Tested-by: RENARD Pierre-Francois Cc: Stefan Wahren Cc: Woojung Huh Cc: Microchip Linux Driver Support Signed-off-by: David S. Miller --- drivers/net/usb/lan78xx.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/net/usb/lan78xx.c b/drivers/net/usb/lan78xx.c index fb4781080d6d..75bdfae5f3e2 100644 --- a/drivers/net/usb/lan78xx.c +++ b/drivers/net/usb/lan78xx.c @@ -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; -- 2.30.2