net: usb: ax88179_178a: stop lying about skb->truesize

Some usb drivers try to set small skb->truesize and break
core networking stacks.

In this patch, I removed one of the skb->truesize overide.

I also replaced one skb_clone() by an allocation of a fresh
and small skb, to get minimally sized skbs, like we did
in commit 1e2c611723 ("net: cdc_ncm: reduce skb truesize
in rx path")

Fixes: f8ebb3ac88 ("net: usb: ax88179_178a: Fix packet receiving")
Reported-by: shironeko <shironeko@tesaguri.club>
Closes: https://lore.kernel.org/netdev/c110f41a0d2776b525930f213ca9715c@tesaguri.club/
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Jose Alonso <joalonsof@gmail.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/20240421193828.1966195-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Eric Dumazet 2024-04-21 19:38:28 +00:00 committed by Jakub Kicinski
parent 58a4c9b1e5
commit 4ce62d5b2f

View File

@ -1456,21 +1456,16 @@ static int ax88179_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
/* Skip IP alignment pseudo header */
skb_pull(skb, 2);
skb->truesize = SKB_TRUESIZE(pkt_len_plus_padd);
ax88179_rx_checksum(skb, pkt_hdr);
return 1;
}
ax_skb = skb_clone(skb, GFP_ATOMIC);
ax_skb = netdev_alloc_skb_ip_align(dev->net, pkt_len);
if (!ax_skb)
return 0;
skb_trim(ax_skb, pkt_len);
skb_put(ax_skb, pkt_len);
memcpy(ax_skb->data, skb->data + 2, pkt_len);
/* Skip IP alignment pseudo header */
skb_pull(ax_skb, 2);
skb->truesize = pkt_len_plus_padd +
SKB_DATA_ALIGN(sizeof(struct sk_buff));
ax88179_rx_checksum(ax_skb, pkt_hdr);
usbnet_skb_return(dev, ax_skb);