Re: [PATCH] usb: gadget: f_mass_storage: fix null pointer dereference in fsg_common_set_num_buffers()

[Greg KH <gregkh@linuxfoundation.org>]

On Mon, Aug 17, 2026 at 06:32:08PM +0530, Jeffin Philip wrote:
> On Mon, 17 Aug 2026 13:10:27 +0200, Greg KH wrote:
> >But that is probably a bad idea, right?  Shouldn't we fix that error
> >first?
> 
> Thanks for the review. Don't quite understand what I need to fix here
> (respectfully), should we harden the buffhds null check to include 
> ZERO_SIZE_PTRs too, something like this should suffice?:
> 
> diff --git a/drivers/usb/gadget/function/f_mass_storage.c b/drivers/usb/gadget/function/f_mass_storage.c
> index 640d3bcb7bf0..98643d53cc7a 100644
> --- a/drivers/usb/gadget/function/f_mass_storage.c
> +++ b/drivers/usb/gadget/function/f_mass_storage.c
> @@ -2747,11 +2747,11 @@ int fsg_common_set_num_buffers(struct fsg_common *common, unsigned int n)
>  	struct fsg_buffhd *bh, *buffhds;
>  	int i;
>   
>  	buffhds = kzalloc_objs(*buffhds, n);
> -	if (!buffhds)
> +	if (ZERO_OR_NULL_PTR(buffhds))

That doesn't look right, think about what your previous commit said it
was doing and why I thought that was a bad idea.

Was it created by a LLM?

thanks,

greg k-h