Re: [PATCH] block: partitions: Replace pp_buf with struct seq_buf

[Andy Shevchenko <andriy.shevchenko@linux.intel.com>]

On Mon, Mar 23, 2026 at 10:51:49AM +0200, Andy Shevchenko wrote:
> On Fri, Mar 20, 2026 at 05:48:44PM -0700, Kees Cook wrote:

...

> > -			char tmp[42];
> >  
> >  			__be32 *dt = (__be32 *)dostype;
> >  			*dt = pb->pb_Environment[16];
> >  			if (dostype[3] < ' ')
> > -				snprintf(tmp, sizeof(tmp), " (%c%c%c^%c)",
> > -					dostype[0], dostype[1],
> > -					dostype[2], dostype[3] + '@' );
> > +				seq_buf_printf(&state->pp_buf,
> > +					       " (%c%c%c^%c)",
> > +					       dostype[0], dostype[1],
> > +					       dostype[2],
> > +					       dostype[3] + '@');
> >  			else
> > -				snprintf(tmp, sizeof(tmp), " (%c%c%c%c)",
> > -					dostype[0], dostype[1],
> > -					dostype[2], dostype[3]);
> > -			strlcat(state->pp_buf, tmp, PAGE_SIZE);
> > -			snprintf(tmp, sizeof(tmp), "(res %d spb %d)",
> > -				be32_to_cpu(pb->pb_Environment[6]),
> > -				be32_to_cpu(pb->pb_Environment[4]));
> > -			strlcat(state->pp_buf, tmp, PAGE_SIZE);
> > +				seq_buf_printf(&state->pp_buf,
> > +					       " (%c%c%c%c)",
> > +					       dostype[0], dostype[1],
> > +					       dostype[2], dostype[3]);
> 
> Wouldn't
> 				seq_buf_printf(&state->pp_buf, " (%.4s)", dostype);
> 
> work?
> 
> But probably okay as in the previous branch it needs more work to follow,
> something like
> 
> 			char dostype[8];
> 			...
> 			if (dostype[3] < ' ') {
> 				/* Escape control character */
> 				dostype[4] = dostype[3] + '@';
> 				dostype[3] = '^';
> 				seq_buf_printf(&state->pp_buf, " (%.5s)", dostype);
> 			} else {
> 				seq_buf_printf(&state->pp_buf, " (%.4s)", dostype);
> 			}

Or maybe even replace the whole conditional with

			seq_buf_printf(&state->pp_buf, " (%4pE)", dostype);

What do you think?

> Taking how invasive is this, it might be better to done separately.
> 
> > +			seq_buf_printf(&state->pp_buf, "(res %d spb %d)",
> > +				       be32_to_cpu(pb->pb_Environment[6]),
> > +				       be32_to_cpu(pb->pb_Environment[4]));

-- 
With Best Regards,
Andy Shevchenko