[PATCH bpf] xsk: re-add queue id check for XDP_SKB path

["Björn Töpel" <bjorn.topel@gmail.com>]

From: Björn Töpel <bjorn.topel@intel.com>

Commit 173d3adb6f43 ("xsk: add zero-copy support for Rx") introduced a
regression on the XDP_SKB receive path, when the queue id checks were
removed. Now, they are back again.

Fixes: 173d3adb6f43 ("xsk: add zero-copy support for Rx")
Reported-by: Qi Zhang <qi.z.zhang@intel.com>
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
---
 net/xdp/xsk.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c
index 36919a254ba3..3b3410ada097 100644
--- a/net/xdp/xsk.c
+++ b/net/xdp/xsk.c
@@ -118,6 +118,9 @@ int xsk_generic_rcv(struct xdp_sock *xs, struct xdp_buff *xdp)
 	u64 addr;
 	int err;
 
+	if (xs->dev != xdp->rxq->dev || xs->queue_id != xdp->rxq->queue_index)
+		return -EINVAL;
+
 	if (!xskq_peek_addr(xs->umem->fq, &addr) ||
 	    len > xs->umem->chunk_size_nohr) {
 		xs->rx_dropped++;
-- 
2.14.1