Re: [PATCH v2 2/2] staging: wfx: check the return value of devm_kmalloc()

Greg KH
2022-02-21T17:05:30Z

On Fri, Feb 18, 2022 at 10:04:02PM +0800, xkernel.wang@foxmail.com wrote:
> From: Xiaoke Wang <xkernel.wang@foxmail.com>
>
> devm_kmalloc() returns a pointer to allocated memory on success, NULL
> on failure. While there is a memory allocation of devm_kmalloc()
> without proper check. It is better to check the return value of it to
> prevent wrong memory access.
> And I use the err label which is introduced by the previous patch to
> handle the error.
>
> Signed-off-by: Xiaoke Wang <xkernel.wang@foxmail.com>
> ---
> Changelog
> v1->v2 update the description.
> drivers/staging/wfx/main.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/drivers/staging/wfx/main.c b/drivers/staging/wfx/main.c
> index 9ff69c5..85fcdc3 100644
> --- a/drivers/staging/wfx/main.c
> +++ b/drivers/staging/wfx/main.c
> @@ -294,6 +294,9 @@ struct wfx_dev *wfx_init_common(struct device *dev,
> hw->wiphy->n_iface_combinations = ARRAY_SIZE(wfx_iface_combinations);
> hw->wiphy->iface_combinations = wfx_iface_combinations;
> hw->wiphy->bands[NL80211_BAND_2GHZ] = devm_kmalloc(dev, sizeof(wfx_band_2ghz), GFP_KERNEL);
> + if (!hw->wiphy->bands[NL80211_BAND_2GHZ])
> + goto err;
> +
> // FIXME: also copy wfx_rates and wfx_2ghz_chantable
> memcpy(hw->wiphy->bands[NL80211_BAND_2GHZ], &wfx_band_2ghz,
> sizeof(wfx_band_2ghz));
> --

This patch does not apply to my tree at all. Please rebase and resend.

thanks,

greg k-h