From d405eb1150ce83f24bdaf935e362af2982db8a2f Mon Sep 17 00:00:00 2001 From: Tim Gardner Date: Tue, 19 Oct 2021 12:19:50 -0600 Subject: [PATCH] net: enetc: unmap DMA in enetc_send_cmd() [ Upstream commit cd4bc63de774eee95e9bac26a565cd80e0fca421 ] Coverity complains of a possible dereference of a null return value. 5. returned_null: kzalloc returns NULL. [show details] 6. var_assigned: Assigning: si_data = NULL return value from kzalloc. 488 si_data = kzalloc(data_size, __GFP_DMA | GFP_KERNEL); 489 cbd.length = cpu_to_le16(data_size); 490 491 dma = dma_map_single(&priv->si->pdev->dev, si_data, 492 data_size, DMA_FROM_DEVICE); While this kzalloc() is unlikely to fail, I did notice that the function returned without unmapping si_data. Fix this by refactoring the error paths and checking for kzalloc() failure. Fixes: 888ae5a3952ba ("net: enetc: add tc flower psfp offload driver") Cc: Claudiu Manoil Cc: "David S. Miller" Cc: Jakub Kicinski Cc: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org (open list) Signed-off-by: Tim Gardner Acked-by: Claudiu Manoil Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- .../net/ethernet/freescale/enetc/enetc_qos.c | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-) diff --git a/drivers/net/ethernet/freescale/enetc/enetc_qos.c b/drivers/net/ethernet/freescale/enetc/enetc_qos.c index dbceb99c4441..9e6988fd3787 100644 --- a/drivers/net/ethernet/freescale/enetc/enetc_qos.c +++ b/drivers/net/ethernet/freescale/enetc/enetc_qos.c @@ -486,14 +486,16 @@ static int enetc_streamid_hw_set(struct enetc_ndev_priv *priv, data_size = sizeof(struct streamid_data); si_data = kzalloc(data_size, __GFP_DMA | GFP_KERNEL); + if (!si_data) + return -ENOMEM; cbd.length = cpu_to_le16(data_size); dma = dma_map_single(&priv->si->pdev->dev, si_data, data_size, DMA_FROM_DEVICE); if (dma_mapping_error(&priv->si->pdev->dev, dma)) { netdev_err(priv->si->ndev, "DMA mapping failed!\n"); - kfree(si_data); - return -ENOMEM; + err = -ENOMEM; + goto out; } cbd.addr[0] = lower_32_bits(dma); @@ -513,12 +515,10 @@ static int enetc_streamid_hw_set(struct enetc_ndev_priv *priv, err = enetc_send_cmd(priv->si, &cbd); if (err) - return -EINVAL; + goto out; - if (!enable) { - kfree(si_data); - return 0; - } + if (!enable) + goto out; /* Enable the entry overwrite again incase space flushed by hardware */ memset(&cbd, 0, sizeof(cbd)); @@ -563,6 +563,10 @@ static int enetc_streamid_hw_set(struct enetc_ndev_priv *priv, } err = enetc_send_cmd(priv->si, &cbd); +out: + if (!dma_mapping_error(&priv->si->pdev->dev, dma)) + dma_unmap_single(&priv->si->pdev->dev, dma, data_size, DMA_FROM_DEVICE); + kfree(si_data); return err;