On Mon, 10 Jan 2022 10:56:49 -0500
Chuck Lever <chuck.lever@xxxxxxxxxx> wrote:
> The patches in this series address a simple buffer over-read bug in
> the Linux NFS server.
>
> However I was thinking it would be nice to have trace helpers to
> deal safely with generic socket addresses. I'd like to be able to
> treat them the same way we currently treat strings. So for example:
>
>
> #define field_sockaddr(field, len) __dynamic_array(u8, field, len)
> #define assign_sockaddr(dest, src, len) memcpy(__get_dynamic_array(dest), src, len)
> #define __get_sockaddr(field) ((struct sockaddr *)__get_dynamic_array(field))
>
> TRACE_EVENT(sockaddr_example,
> TP_PROTO(
> const struct sockaddr *sap,
> size_t salen
> ),
> TP_ARGS(sap, salen),
> TP_STRUCT__entry(
> __field_sockaddr(addr, salen)
> ),
> TP_fast_assign(
> __assign_sockaddr(addr, sap, salen);
> ),
> TP_printk("addr=%pIS", __get_sockaddr(addr))
> );
>
>
> should be able to store any address family in a dynamically-sized
> array field (addr).
>
> I haven't quite been able to figure out how to handle the
> TP_printk() part of this equation. `trace-cmd report` displays
> something like "addr=ARG TYPE NOT FIELD BUT 7".
>
> Thoughts or advice appreciated.
I'll take a look into it.
Thanks,
-- Steve
