Re: [PATCH] perf dwarf-regs: s390: Fix an off by one bug

From: Dan Carpenter

Date: Thu Apr 23 2026 - 16:28:16 EST


On Thu, Apr 23, 2026 at 01:24:50PM -0700, Ian Rogers wrote:
> On Thu, Apr 23, 2026 at 12:07 AM Dan Carpenter <error27@xxxxxxxxx> wrote:
> >
> > Change the > comparison to >= to prevent an out of bounds access of
> > the dwarf_s390_regnums[] array.
> >
> > Fixes: 1e452dd850f3 ("perf dwarf-regs: Add S390 perf to DWARF register number mapping functions")
> > Signed-off-by: Dan Carpenter <error27@xxxxxxxxx>
> > ---
> > tools/perf/util/dwarf-regs-arch/dwarf-regs-s390.c | 1 +-
> > 1 files changed, 1 insertions(+), 1 deletions(-)
> >
> > diff --git a/tools/perf/util/dwarf-regs-arch/dwarf-regs-s390.c b/tools/perf/util/dwarf-regs-arch/dwarf-regs-s390.c
> > index 310a37451bdc..f79216a7665a 100644
> > --- a/tools/perf/util/dwarf-regs-arch/dwarf-regs-s390.c
> > +++ b/tools/perf/util/dwarf-regs-arch/dwarf-regs-s390.c
> > @@ -45,7 +45,7 @@ int __get_dwarf_regnum_for_perf_regnum_s390(int perf_regnum)
> > if (perf_regnum == 0)
> > return 0;
> >
> > - if (perf_regnum < 0 || perf_regnum > (int)ARRAY_SIZE(dwarf_s390_regnums) ||
> > + if (perf_regnum < 0 || perf_regnum >= (int)ARRAY_SIZE(dwarf_s390_regnums) ||
>
> It looks like this mistake was copy-pasted into these files as well:
> - tools/perf/util/dwarf-regs-arch/dwarf-regs-csky.c
> - tools/perf/util/dwarf-regs-arch/dwarf-regs-x86.c
> - tools/perf/util/dwarf-regs-arch/dwarf-regs-powerpc.c
>
> Could you fix them all?

Sure. Do you want that as four separate patches or just one patch with
four Fixes tags?

regards,
dan carpenter