drivers/net/usb/asix.c: Fix unaligned accesses (3f78d1f2) · Commits · 戴 / test

drivers/net/usb/asix.c

+33 −1

Original line number	Diff line number	Diff line
		@@ -322,8 +322,29 @@ static int asix_rx_fixup(struct usbnet dev, struct sk_buff skb)
		/* get the packet length */
		size = (u16) (header & 0x0000ffff);

		if ((skb->len) - ((size + 1) & 0xfffe) == 0)
		if ((skb->len) - ((size + 1) & 0xfffe) == 0) {
		u8 alignment = (u32)skb->data & 0x3;
		if (alignment != 0x2) {
		/*
		* not 16bit aligned so use the room provided by
		* the 32 bit header to align the data
		*
		* note we want 16bit alignment as MAC header is
		* 14bytes thus ip header will be aligned on
		* 32bit boundary so accessing ipheader elements
		* using a cast to struct ip header wont cause
		* an unaligned accesses.
		*/
		u8 realignment = (alignment + 2) & 0x3;
		memmove(skb->data - realignment,
		skb->data,
		size);
		skb->data -= realignment;
		skb_set_tail_pointer(skb, size);
		}
		return 2;
		}

		if (size > ETH_FRAME_LEN) {
		netdev_err(dev->net, "asix_rx_fixup() Bad RX Length %d\n",
		size);
		@@ -331,7 +352,18 @@ static int asix_rx_fixup(struct usbnet dev, struct sk_buff skb)
		}
		ax_skb = skb_clone(skb, GFP_ATOMIC);
		if (ax_skb) {
		u8 alignment = (u32)packet & 0x3;
		ax_skb->len = size;

		if (alignment != 0x2) {
		/*
		* not 16bit aligned use the room provided by
		* the 32 bit header to align the data
		*/
		u8 realignment = (alignment + 2) & 0x3;
		memmove(packet - realignment, packet, size);
		packet -= realignment;
		}
		ax_skb->data = packet;
		skb_set_tail_pointer(ax_skb, size);
		usbnet_skb_return(dev, ax_skb);