diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index fe4562d395e3..58ad40e17a74 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -483,7 +483,7 @@ xdp_xmit: * anymore. */ static struct page *xdp_linearize_page(struct receive_queue *rq, - u16 num_buf, + u16 *num_buf, struct page *p, int offset, unsigned int *len) @@ -497,7 +497,7 @@ static struct page *xdp_linearize_page(struct receive_queue *rq, memcpy(page_address(page) + page_off, page_address(p) + offset, *len); page_off += *len; - while (--num_buf) { + while (--*num_buf) { unsigned int buflen; unsigned long ctx; void *buf; @@ -507,19 +507,22 @@ static struct page *xdp_linearize_page(struct receive_queue *rq, if (unlikely(!ctx)) goto err_buf; - /* guard against a misconfigured or uncooperative backend that - * is sending packet larger than the MTU. - */ - if ((page_off + buflen) > PAGE_SIZE) - goto err_buf; - buf = mergeable_ctx_to_buf_address(ctx); p = virt_to_head_page(buf); off = buf - page_address(p); + /* guard against a misconfigured or uncooperative backend that + * is sending packet larger than the MTU. + */ + if ((page_off + buflen) > PAGE_SIZE) { + put_page(p); + goto err_buf; + } + memcpy(page_address(page) + page_off, page_address(p) + off, buflen); page_off += buflen; + put_page(p); } *len = page_off; @@ -555,7 +558,7 @@ static struct sk_buff *receive_mergeable(struct net_device *dev, /* This happens when rx buffer size is underestimated */ if (unlikely(num_buf > 1)) { /* linearize data for XDP */ - xdp_page = xdp_linearize_page(rq, num_buf, + xdp_page = xdp_linearize_page(rq, &num_buf, page, offset, &len); if (!xdp_page) goto err_xdp;