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

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

[cgel.zte]

From: Minghao Chi <chi.minghao@zte.com.cn>

Checking a pointer for NULL before calling kfree() on it is redundant,
kfree() deals with NULL pointers just fine.

Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Minghao Chi <chi.minghao@zte.com.cn>
---
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

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

[Greg KH]

On Mon, Jun 13, 2022 at 01:31:16AM +0000, cgel.zte@gmail.com wrote:
> From: Minghao Chi <chi.minghao@zte.com.cn>
> 
> Checking a pointer for NULL before calling kfree() on it is redundant,
> kfree() deals with NULL pointers just fine.
> 
> Reported-by: Zeal Robot <zealci@zte.com.cn>
> Signed-off-by: Minghao Chi <chi.minghao@zte.com.cn>
> ---
> 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
writing the same thing over and over, yet to different people), I was
created.  Hopefully you will not take offence and will fix the problem
in your patch and resubmit it so that it can be accepted into the Linux
kernel tree.

You are receiving this message because of the following common error(s)
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If you wish to discuss this problem further, or you have questions about
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thanks,

greg k-h's patch email bot