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: 888ae5a395 ("net: enetc: add tc flower psfp offload driver")
Cc: Claudiu Manoil <claudiu.manoil@nxp.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org (open list)
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Acked-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Tim Gardner 2021-10-19 12:19:50 -06:00 committed by Greg Kroah-Hartman
parent 14e12b7a76
commit d405eb1150

View File

@ -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;