From:   Jiasheng Jiang <jiasheng@iscas.ac.cn>
To:     ecree.xilinx@gmail.com, habetsm.xilinx@gmail.com,
        davem@davemloft.net, kuba@kernel.org
Cc:     netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        Jiasheng Jiang <jiasheng@iscas.ac.cn>
Subject: [PATCH] sfc: falcon: Check null pointer of rx_queue->page_ring
Date:   Mon, 20 Dec 2021 22:03:44 +0800
Message-Id: <20211220140344.978408-1-jiasheng@iscas.ac.cn>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

Because of the possible failure of the kcalloc, it should be better to
set rx_queue->page_ptr_mask to 0 when it happens in order to maintain
the consistency.

Fixes: 5a6681e22c14 ("sfc: separate out SFC4000 ("Falcon") support into new sfc-falcon driver")
Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
---
 drivers/net/ethernet/sfc/falcon/rx.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/sfc/falcon/rx.c b/drivers/net/ethernet/sfc/falcon/rx.c
index 966f13e7475d..11a6aee852e9 100644
--- a/drivers/net/ethernet/sfc/falcon/rx.c
+++ b/drivers/net/ethernet/sfc/falcon/rx.c
@@ -728,7 +728,10 @@ static void ef4_init_rx_recycle_ring(struct ef4_nic *efx,
 					    efx->rx_bufs_per_page);
 	rx_queue->page_ring = kcalloc(page_ring_size,
 				      sizeof(*rx_queue->page_ring), GFP_KERNEL);
-	rx_queue->page_ptr_mask = page_ring_size - 1;
+	if (!rx_queue->page_ring)
+		rx_queue->page_ptr_mask = 0;
+	else
+		rx_queue->page_ptr_mask = page_ring_size - 1;
 }
 
 void ef4_init_rx_queue(struct ef4_rx_queue *rx_queue)
-- 
2.25.1