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

["Linus Probert" <linus.probert@gmail.com>]

On Thu Apr 23, 2026 at 9:07 AM CEST, Dan Carpenter 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@gmail.com>
> ---
>  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) ||
                     ^^
Why leave the two spaces?

>  	    dwarf_s390_regnums[perf_regnum] == 0)
>  		return -ENOENT;
>  

Br,
Linus