On Wed, 9 Nov 2022 at 14:34, Yang Yingliang <yangyingliang@xxxxxxxxxx> wrote:
>
> mmc_add_host() may return error, if we ignore its return value,
> it will lead two issues:
> 1. The memory that allocated in mmc_alloc_host() is leaked.
> 2. In the remove() path, mmc_remove_host() will be called to
> delete device, but it's not added yet, it will lead a kernel
> crash because of null-ptr-deref in device_del().
>
>
> So fix this by checking the return value and goto error path which
> will call mmc_free_host(), besides, other resources also need be
> released.
>
> Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
> Signed-off-by: Yang Yingliang <yangyingliang@xxxxxxxxxx>
Applied for next, thanks!
Kind regards
Uffe
> ---
> drivers/mmc/host/wbsd.c | 12 +++++++++++-
> 1 file changed, 11 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/mmc/host/wbsd.c b/drivers/mmc/host/wbsd.c
> index 67ecd342fe5f..7c7ec8d10232 100644
> --- a/drivers/mmc/host/wbsd.c
> +++ b/drivers/mmc/host/wbsd.c
> @@ -1698,7 +1698,17 @@ static int wbsd_init(struct device *dev, int base, int irq, int dma,
> */
> wbsd_init_device(host);
>
> - mmc_add_host(mmc);
> + ret = mmc_add_host(mmc);
> + if (ret) {
> + if (!pnp)
> + wbsd_chip_poweroff(host);
> +
> + wbsd_release_resources(host);
> + wbsd_free_mmc(dev);
> +
> + mmc_free_host(mmc);
> + return ret;
> + }
>
> pr_info("%s: W83L51xD", mmc_hostname(mmc));
> if (host->chip_id != 0)
> --
> 2.25.1
>
