linux-kernel - [PATCH 5.8 005/633] mlx4: handle non-napi callers to napi

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20201027135522.925297023@linuxfoundation.org>
Date:   Tue, 27 Oct 2020 14:45:48 +0100
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Jonathan Lemon <jonathan.lemon@...il.com>,
        Tariq Toukan <tariqt@...dia.com>,
        Jakub Kicinski <kuba@...nel.org>
Subject: [PATCH 5.8 005/633] mlx4: handle non-napi callers to napi_poll

From: Jonathan Lemon <bsd@...com>

[ Upstream commit b2b8a92733b288128feb57ffa694758cf475106c ]

netcons calls napi_poll with a budget of 0 to transmit packets.
Handle this by:
 - skipping RX processing
 - do not try to recycle TX packets to the RX cache

Signed-off-by: Jonathan Lemon <jonathan.lemon@...il.com>
Reviewed-by: Tariq Toukan <tariqt@...dia.com>
Signed-off-by: Jakub Kicinski <kuba@...nel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
---
 drivers/net/ethernet/mellanox/mlx4/en_rx.c |    3 +++
 drivers/net/ethernet/mellanox/mlx4/en_tx.c |    2 +-
 2 files changed, 4 insertions(+), 1 deletion(-)

--- a/drivers/net/ethernet/mellanox/mlx4/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
@@ -943,6 +943,9 @@ int mlx4_en_poll_rx_cq(struct napi_struc
 	bool clean_complete = true;
 	int done;
 
+	if (!budget)
+		return 0;
+
 	if (priv->tx_ring_num[TX_XDP]) {
 		xdp_tx_cq = priv->tx_cq[TX_XDP][cq->ring];
 		if (xdp_tx_cq->xdp_busy) {
--- a/drivers/net/ethernet/mellanox/mlx4/en_tx.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_tx.c
@@ -350,7 +350,7 @@ u32 mlx4_en_recycle_tx_desc(struct mlx4_
 		.dma = tx_info->map0_dma,
 	};
 
-	if (!mlx4_en_rx_recycle(ring->recycle_ring, &frame)) {
+	if (!napi_mode || !mlx4_en_rx_recycle(ring->recycle_ring, &frame)) {
 		dma_unmap_page(priv->ddev, tx_info->map0_dma,
 			       PAGE_SIZE, priv->dma_dir);
 		put_page(tx_info->page);