Re: [PATCH bpf-next 1/2] bpf: add bpf_dynptr_memset() kfunc

[Eduard Zingerman <eddyz87@xxxxxxxxx>]

On Thu, 2025-06-19 at 10:55 -0700, Ihor Solodrai wrote:

[...]

> > I think Mykyta has kernel/trace/bpf_trace.c:__bpf_dynptr_copy_str() in mind.
> 
> Thanks for the pointer. So it looks like memset can use
> bpf_dynptr_slice_rdwr() to handle xdp/skb cases. Something like:
> 
>      void *ptr = bpf_dynptr_slice_rdwr(&dynptr, 0, buffer, sizeof(buffer));
>      if (!ptr)
>          return -EINVAL;
> 
>      memset(ptr, val, n);
> 
>      if (ptr == buffer)
>          bpf_dynptr_write(&dynptr, 0, buffer, sizeof(buffer), 0);
> 
> 

I think so. In a loop.