Re: [PATCH V2] usb: core: Remove redundant NULL checks before kfree

From: Greg KH
Date: Tue Jun 21 2022 - 10:32:28 EST


On Mon, Jun 13, 2022 at 01:31:16AM +0000, cgel.zte@xxxxxxxxx wrote:
> From: Minghao Chi <chi.minghao@xxxxxxxxxx>
>
> Checking a pointer for NULL before calling kfree() on it is redundant,
> kfree() deals with NULL pointers just fine.
>
> Reported-by: Zeal Robot <zealci@xxxxxxxxxx>
> Signed-off-by: Minghao Chi <chi.minghao@xxxxxxxxxx>
> ---
> v1->v2:
> remove "quirk_list = NULL"
> drivers/usb/core/quirks.c | 5 +----
> 1 file changed, 1 insertion(+), 4 deletions(-)
>
> diff --git a/drivers/usb/core/quirks.c b/drivers/usb/core/quirks.c
> index f99a65a64588..9ec12c42db30 100644
> --- a/drivers/usb/core/quirks.c
> +++ b/drivers/usb/core/quirks.c
> @@ -56,10 +56,7 @@ static int quirks_param_set(const char *value, const
> struct kernel_param *kp)
> if (val[i] == ',')
> quirk_count++;
>
> - if (quirk_list) {
> - kfree(quirk_list);
> - quirk_list = NULL;
> - }
> + kfree(quirk_list);
>
> quirk_list = kcalloc(quirk_count, sizeof(struct quirk_entry),
> GFP_KERNEL);
> --
> 2.25.1
>

Hi,

This is the friendly patch-bot of Greg Kroah-Hartman. You have sent him
a patch that has triggered this response. He used to manually respond
to these common problems, but in order to save his sanity (he kept
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