static int tigon3_dma_hwbug_workaround(struct tg3_napi *tnapi,
				       struct sk_buff **pskb,
				       u32 *entry, u32 *budget,
				       u32 base_flags, u32 mss, u32 vlan)
{
	struct tg3 *tp = tnapi->tp;
	struct sk_buff *new_skb, *skb = *pskb;
	dma_addr_t new_addr = 0;
	int ret = 0;

	if (tg3_asic_rev(tp) != ASIC_REV_5701)
		new_skb = skb_copy(skb, GFP_ATOMIC);
	else {
		int more_headroom = 4 - ((unsigned long)skb->data & 3);

		new_skb = skb_copy_expand(skb,
					  skb_headroom(skb) + more_headroom,
					  skb_tailroom(skb), GFP_ATOMIC);
	}

	if (!new_skb) {
		ret = -1;
	} else {
		/* New SKB is guaranteed to be linear. */
		new_addr = pci_map_single(tp->pdev, new_skb->data, new_skb->len,
					  PCI_DMA_TODEVICE);
		/* Make sure the mapping succeeded */
		if (pci_dma_mapping_error(tp->pdev, new_addr)) {
			dev_kfree_skb(new_skb);
			ret = -1;
		} else {
			u32 save_entry = *entry;

			base_flags |= TXD_FLAG_END;

			tnapi->tx_buffers[*entry].skb = new_skb;
			dma_unmap_addr_set(&tnapi->tx_buffers[*entry],
					   mapping, new_addr);

			if (tg3_tx_frag_set(tnapi, entry, budget, new_addr,
					    new_skb->len, base_flags,
					    mss, vlan)) {
				tg3_tx_skb_unmap(tnapi, save_entry, -1);
				dev_kfree_skb(new_skb);
				ret = -1;
			}
		}
	}

	dev_kfree_skb(skb);
	*pskb = new_skb;
	return ret;
}

The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.