Re: [PATCH v2 4/5] gdbstub: Add Xfer:siginfo:read stub

[Richard Henderson]

On 3/8/24 08:30, Gustavo Romero wrote:
> Hi Richard!
>
> On 3/7/24 6:13 PM, Richard Henderson wrote:
> > On 3/7/24 08:26, Gustavo Romero wrote:
> > > +void gdb_handle_query_xfer_siginfo(GArray *params, void *user_ctx)
> > > +{
> > > +    unsigned long offset, len;
> > > +    uint8_t *siginfo_offset;
> > > +
> > > +    offset = get_param(params, 0)->val_ul;
> > > +    len = get_param(params, 1)->val_ul;
> > > +
> > > +    if (offset + len > sizeof(target_siginfo_t)) {
> >
> > If you save the siginfo_len from gdb_handlesig, you can place this in user.c
> Shouldn't all user-only stubs be placed in user-target.c? Like
> gdb_handle_query_xfer_auxv and gdb_handle_query_xfer_exec_file, and since
> what controls the inclusion in the build of user-target.c is CONFIG_USER_ONLY?

user.c is also build for CONFIG_USER_ONLY, except that it is compiled only once, and has 
no target-specific code in it.

> > Is it really correct to reject (offset == 0) + (len == large), rather than 
> > truncate len?
>
> I think this is correct. GDB mentions briefly that an invalid offset
> should be treated as an error. Thus, I think that a valid offset but
> a non-existing/invalid (large) length should be treated the same,
> cause in the end data on invalid offsets are being requested anyways.

Ok.


r~