On Tue, 8 May 2018 23:47:36 +0300
Alexey Khoroshilov <khoroshi...@ispras.ru> wrote:
> nxp_spifi_probe() increments refcnt of SPI flash device node by
> of_get_next_available_child() and then it passes the node
> to mtd device in nxp_spifi_setup_flash().
> But if a failure happens before mtd_device_register() succeed,
> the refcnt is left undecremented.
Why not doing that in the error path of the probe function? Also, you
probably want to call of_node_put() in the ->remove() function.
>
> Found by Linux Driver Verification project (linuxtesting.org).
>
> Signed-off-by: Alexey Khoroshilov <khoroshi...@ispras.ru>
> ---
> drivers/mtd/spi-nor/nxp-spifi.c | 16 +++++++++++-----
> 1 file changed, 11 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/mtd/spi-nor/nxp-spifi.c b/drivers/mtd/spi-nor/nxp-spifi.c
> index 15374216d4d9..8919e31f2ab8 100644
> --- a/drivers/mtd/spi-nor/nxp-spifi.c
> +++ b/drivers/mtd/spi-nor/nxp-spifi.c
> @@ -294,7 +294,8 @@ static int nxp_spifi_setup_flash(struct nxp_spifi *spifi,
> break;
> default:
> dev_err(spifi->dev, "unsupported rx-bus-width\n");
> - return -EINVAL;
> + ret = -EINVAL;
> + goto err_node_put;
> }
> }
>
> @@ -328,7 +329,8 @@ static int nxp_spifi_setup_flash(struct nxp_spifi *spifi,
> break;
> default:
> dev_err(spifi->dev, "only mode 0 and 3 supported\n");
> - return -EINVAL;
> + ret = -EINVAL;
> + goto err_node_put;
> }
>
> writel(ctrl, spifi->io_base + SPIFI_CTRL);
> @@ -356,22 +358,26 @@ static int nxp_spifi_setup_flash(struct nxp_spifi
> *spifi,
> ret = spi_nor_scan(&spifi->nor, NULL, &hwcaps);
> if (ret) {
> dev_err(spifi->dev, "device scan failed\n");
> - return ret;
> + goto err_node_put;
> }
>
> ret = nxp_spifi_setup_memory_cmd(spifi);
> if (ret) {
> dev_err(spifi->dev, "memory command setup failed\n");
> - return ret;
> + goto err_node_put;
> }
>
> ret = mtd_device_register(&spifi->nor.mtd, NULL, 0);
> if (ret) {
> dev_err(spifi->dev, "mtd device parse failed\n");
> - return ret;
> + goto err_node_put;
> }
>
> return 0;
> +
> +err_node_put:
> + of_node_put(np);
> + return ret;
> }
>
> static int nxp_spifi_probe(struct platform_device *pdev)
