sfc: Check null pointer of rx_queue->page_ring

[ Upstream commit bdf1b5c3884f6a0dc91b0dbdb8c3b7d205f449e0 ]

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>
Acked-by: Martin Habets <habetsm.xilinx@gmail.com>
Link: https://lore.kernel.org/r/20211220135603.954944-1-jiasheng@iscas.ac.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/net/ethernet/sfc/rx_common.c b/drivers/net/ethernet/sfc/rx_common.c
index 68fc7d3..0983abc 100644 (file)
--- a/drivers/net/ethernet/sfc/rx_common.c
+++ b/drivers/net/ethernet/sfc/rx_common.c
@@ -150,7 +150,10 @@ static void efx_init_rx_recycle_ring(struct efx_rx_queue *rx_queue)
                                            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;
 }
 
 static void efx_fini_rx_recycle_ring(struct efx_rx_queue *rx_queue)