Re: [PATCH v1 1/1] libceph: Amend checking to fix `make W=1` build breakage

From: andriy.shevchenko@xxxxxxxxxxxxxxx
Date: Mon Nov 24 2025 - 10:09:53 EST


On Mon, Nov 10, 2025 at 08:39:49PM +0000, Viacheslav Dubeyko wrote:
> On Mon, 2025-11-10 at 21:36 +0200, andriy.shevchenko@xxxxxxxxxxxxxxx wrote:
> > On Mon, Nov 10, 2025 at 07:28:36PM +0000, Viacheslav Dubeyko wrote:
> > > On Mon, 2025-11-10 at 15:46 +0100, Andy Shevchenko wrote:

...

> > > > ceph_decode_32_safe(p, end, len, e_inval);
> > > > if (len == 0 && incremental)
> > > > return NULL; /* new_pg_temp: [] to remove */
> > > > - if (len > (SIZE_MAX - sizeof(*pg)) / sizeof(u32))
> > > > + if ((size_t)len > (SIZE_MAX - sizeof(*pg)) / sizeof(u32))
> > > > return ERR_PTR(-EINVAL);
> > > >
> > > > ceph_decode_need(p, end, len * sizeof(u32), e_inval);
> >
> > > I am guessing... What if we change the declaration of len on size_t, then could
> > > it be more clear solution here? For example, let's consider this for both cases:
> > >
> > > size_t len, i;
> > >
> > > Could it eliminate the issue and to make the Clang happy? Or could it introduce
> > > another warnings/issues?
> >
> > Probably, but the code is pierced with the sizeof(u32) and alike, moreover
> > size_t is architecture-dependent type, while the set of macros in decode.h
> > seems to operate on the fixed-width type. That said, I prefer my way of fixing
> > this. But if you find another, better one, I am all ears!
> >
> > *Also note, I'm not familiar with the guts of the ceph, so maybe your solution
> > is the best, but I want more people to confirm this.
>
> I think the patch looks good as it is. And we can take it. If we find the better
> way
> of fixing this, then we can do it anytime.
>
> Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@xxxxxxx>

Thanks, can this be applied? My builds are still broken.

--
With Best Regards,
Andy Shevchenko