From 2e2a83b4998af4384e677d3b2ac08565274279bf Mon Sep 17 00:00:00 2001 From: Dexuan Cui Date: Wed, 1 Jul 2026 21:12:36 -0700 Subject: [PATCH] net: mana: Validate the packet length reported by the NIC Validate the packet length reported in the RX CQE before passing it to skb processing. The CQE is supplied by the NIC device and should not be blindly trusted. Cc: stable@vger.kernel.org Reviewed-by: Haiyang Zhang Signed-off-by: Dexuan Cui Fixes: ca9c54d2d6a5 ("net: mana: Add a driver for Microsoft Azure Network Adapter (MANA)") Link: https://patch.msgid.link/20260702041237.617719-2-decui@microsoft.com Signed-off-by: Paolo Abeni --- drivers/net/ethernet/microsoft/mana/mana_en.c | 23 +++++++++++++++---- 1 file changed, 18 insertions(+), 5 deletions(-) diff --git a/drivers/net/ethernet/microsoft/mana/mana_en.c b/drivers/net/ethernet/microsoft/mana/mana_en.c index 7438ea6b3f26..dd4d1c0c582e 100644 --- a/drivers/net/ethernet/microsoft/mana/mana_en.c +++ b/drivers/net/ethernet/microsoft/mana/mana_en.c @@ -2246,12 +2246,25 @@ static void mana_process_rx_cqe(struct mana_rxq *rxq, struct mana_cq *cq, rxbuf_oob = &rxq->rx_oobs[curr]; WARN_ON_ONCE(rxbuf_oob->wqe_inf.wqe_size_in_bu != 1); - mana_refill_rx_oob(dev, rxq, rxbuf_oob, &old_buf, &old_fp); + if (unlikely(pktlen > rxq->datasize)) { + /* Increase it even if mana_rx_skb() isn't called. */ + rxq->rx_cq.work_done++; - /* Unsuccessful refill will have old_buf == NULL. - * In this case, mana_rx_skb() will drop the packet. - */ - mana_rx_skb(old_buf, old_fp, oob, rxq, i); + ++ndev->stats.rx_dropped; + netdev_warn_once(ndev, + "Dropped oversized RX packet: len=%u, datasize=%u\n", + pktlen, rxq->datasize); + + /* Reuse the RX buffer since rxbuf_oob is unchanged. */ + } else { + + mana_refill_rx_oob(dev, rxq, rxbuf_oob, &old_buf, &old_fp); + + /* Unsuccessful refill will have old_buf == NULL. + * In this case, mana_rx_skb() will drop the packet. + */ + mana_rx_skb(old_buf, old_fp, oob, rxq, i); + } mana_move_wq_tail(rxq->gdma_rq, rxbuf_oob->wqe_inf.wqe_size_in_bu);